SparkChess Support

That is a Promotion; a pawn will be promoted to queen (or other piece) if it reaches the last rank. Please consult the official chess rules for details.

Most likely you were the victim of an en-passant take. Don’t feel too bad, many casual players are not familiar with it. Please consult the official chess rules for details.

To castle, you move the king to the desired position – if castling is available, the rook will be moved automatically. Castling is not possible if the king or the rook has moved; or if the king is in check; or if one of the squares the king must travel is controlled by an enemy piece. According to the official FIDE rules, you can castle if the king was in check previously.

Try playing on with a weaker opponent, like Deon or Cody. If you download the Premium Version, you have access to some help tools that will help you make better moves. SparkChess Premium also includes over 20 chess lessons covering the basic rules, strategies, openings and endgames.

You can find more articles and puzzles here on sparkchess.com.

Congratulations! You must be an advanced player; most likely you’ve played in tournaments. Our Chess AI was created to be fun and quick, not brutally strong. If you are an advanced player, you can still enjoy SparkChess’ multiplayer or by using its Board Editor and the PGN/Replay features.

Stalemate occurs when the player who must move is not in check but has no legal moves. This situation happens most frequently when the player has just the King left on the board and any move would place them in check.

A stalemate causes the game to end as a Draw, therefore the player who has the advantage should try to avoid it and checkmate instead, while the disadvantaged player may try to force a stalemate to avoid losing.

If you’re unsure what version of SparkChess you have, it’s easy to find it:

1. Open the game and start a new single-player game against any of the AI opponents.
2. Click on the SparkChess logo at the top-right (top-center on mobile phones). An “About Window” will open.
3. Just below the “About SparkChess” title, you’ll see a text in yellow, like this: “9.1.0 online lite“

The first part (numbers, e.g. 1.2.3 is the version number); the second is the platform (e.g. online, desktop_osx, iphone, etc.); the third is the type (lite or full).

SparkChess AI opponents are engineered to behave like casual human players, not robot overlords. Except for Guru, they’ll play fast and loose and will favor variety over the best move. Cody is child-like an Deon is still learning the basics. So our advice would be to just play and have fun!

If you must know, Claire has an Elo rating of 1500 depending on her mood. Boris is 1700 on a good day and Guru is around 1900-2000. If you really need a stronger opponent, we could go as high as 2100.

There are many ways you can get better at chess, the first being, of course, to play as much as you can. SparkChess has 5 AI opponents for all levels and a multiplayer mode so you can play against other people people like you.

SparkChess Premium includes over 30 lessons on basic topics ranging from rules to openings and endgames and basic strategies and 70 chess puzzles to help you learn how to spot tricky moves.

We also have articles on chess on the site written by accomplished authors (dr. Alexey Root is a Woman International Chess Master). Some articles, such as those written for us by George Zeigler, go in detail, commenting games from start to finish with diagrams. You can follow the progress of these games move by move.

Another way to sharpen your chess skills is to play chess puzzles. We have hand-picked puzzles from games between grandmaster and we’ve included even historical context and info on the players. You can try to solve these puzzles online (they all have solutions). Puzzles are a great way to improve your understanding of the situation and think a few moves ahead. And being games from the masters, you’ll also learn a trick or two.

You can also join a local chess club. Also, iChess.net has many chess video courses available.

They are the same product. When we created the first game engine in 2002, we called it flashCHESS. Later, in 2008 the third generation of the engine, rewritten from scratch, took the web by storm and we wanted to keep the name due to its heritage, naming it flashCHESS III. Later, to prevent any trademark complaints from Adobe regarding the use of “Flash”, we decided to rename the game as SparkChess.

SparkChess^® is registered trademark.

Yes. Online play is free, although we display unobtrusive ads from Google. If you prefer not seeing ads, you can download the standalone version of the game or subscribe to SparkChess Premium Live.

SparkChess could not exist without ads and paying customers. Simply put, they pay the bills.

Developing a game like SparkChess, operating a website with over two million monthly views and maintaining a multiplayer service that needs to be up and responsive 24/7 is not cheap.

For example, we use Cloudflare Business so that the game loads as fast as possible, we use a EV SSL certificate to make sure the connection is secure, DNS with failover so the site never goes down, IP filtering to mitigate attacks, code signing certificates so you can trust downloading the game and so on. We even need to buy mobile phones and tablets to make sure SparkChess runs anywhere. Then there’s development and customer support.

For ads, we’ve been using AdSense exclusively. AdSense has the most strict rules for websites and advertisers and disallow misleading ads, malware or annoying ad types. They don’t pay best, but we feel they are the best for you, the player. We also try not to abuse ads – on any given page you will not find more than 2 ads, even though most sites place far more than that.

We use in-game ads for two main reasons: it’s what Google recommends for games and they allow the game to take up all the screen size. We think it’s a good tradeoff. Currently we show ads when the game starts and then on game over, at least 5 minutes apart.

SparkChess works on any modern browser released within the past 3 years. Supported browsers include:

• Microsoft Edge Browser
• Firefox
• Google Chrome and Chrome for Android
• Safari and iOS Safari.
• Opera, Vivaldi, etc.

If in doubt, we recommend you to use Google Chrome (or its open source brother Chromium) on any platform as it provides all the features SparkChess needs, speed, stability and security.

SparkChess should look and work perfectly on any browser released in the last 3 years. We test it thoroughly and make sure there are no issues on Chrome and Chromium-based browsers (Microsoft Edge, Opera, etc.) as well as on Safari and Firefox.

There are isolated reports of the board not displaying correctly and in some rare cases missing images. The known conditions are:

• older Microsoft Edge with high contrast mode enabled;
• Chrome (or another Chrome-based browser) with a Dark Mode extension.

Extensions can affect your browsing experience in unexpected ways. If you have extensions enabled, try loading SparkChess in an incognito (or private) window, without extensions. It should run fine. You can also try disabling one extension at a time to see which one is misbehaving.

In single-player, player timers go up. They are informative only and players won’t lose a game for thinking too long on a move.

In multiplayer, there are two timer modes, depending on the play area:

• a simple mode – time/move, in which the player must make a move within one minute or whatever the lobby setting is. This is the default for most public lobbies.
• proper time control – game time + bonus per move, in which a total time is allocated per game and then a bonus is given per move. A time control of “10/5” means 10 minutes per game, with a 5 second bonus after each move. The time control may be set up by teams.

We use this setup because we think it’s more beginner-friendly. Your feedback is welcome and we’ll adjust the timing if needed.

Yes. SparkChess is available as a standalone application on many platforms.

SparkChess is available as a native app on:

• Windows – will work on Windows 10 and newer;
• Mac OS X – 10.11 or newer;
• Apple iPhone and iPad – iOS 13 and newer;
• Android devices; – Android 10 and newer;

In addition, SparkChess Premium Live will run in any modern browser, regardless of platform.

Currently we do not have a native Linux version as there’s just not enough interest. SparkChess Premium Live is available on all operating systems that support modern browsers. Please contact us if you require SparkChess as a Linux app and we may reconsider.

Most likely the email sent to you was flagged as spam by your mail server or email application. Please check your Spam/Junk folder. If you can’t find it, please contact us. We’ll do our best to reply to you within two business days and will send you the game.

On Mac OS, SparkChess is distributed as a simple zip, without any DMG/PKG installer. Check your Downloads folder or use Spotlight (CMD+Space) to search for “sparkchess”. After you find it, consider dragging it to Desktop or to the Applications folder.

On Windows, start by checking your Downloads History (press CTRL+J  in your browser to see the list). You can also check your Downloads folder and use Windows Search (press WIN+S) to search for “sparkchess”.

If you still  can’t find it or in the event you lost all the information on your computer, you can download SparkChess again. You’ll need your Transaction ID and email address (or at least the email address you used for purchase to recover the Transaction ID).

If you own an older version, you can upgrade using this upgrade form.

You’re probably launching the free version by mistake. Don’t worry, it happens.

Let’s review the possibilities:

• if you purchased SparkChess for PC or Mac, you no longer need to play the game in your browser. You must locate the downloaded game and install it on your computer. Use CTRL+J / CMD+J from your browser to see the Download History and look for a file containing the word “sparkchess”, e.g. sparkchess17setup.exe on PC or sparkchess17.zip on Mac.
• If you subscribed to Premium Live to play in your browser, you no longer need to access www.sparkchess.com – instead you must open the premium site at premium.sparkchess.com to login.
• On Android and IOS, pay attention to the game icons and names. They are called differently, the full version is “SparkChess Pro”.

SparkChess does not contain any form of malware, spyware, adware or anything harmful. It doesn’t interact with the system beyond loading & saving games and accessing the internet in multiplayer; the installer doesn’t do anything else besides copying files. Still, some overzealous antiviruses may very rarely flag SparkChess and move it to quarantine. (Sometimes, antiviruses manage to actually label themselves as viruses.)

SparkChess was briefly flagged by Norton Antivirus as ‘WS.Reputation1‘, which basically means a file not commonly downloaded (new release – duh!). We worked with Symantec and whitelisted it but the process has to be repeated for every release. You should keep your virus definitions up-to-date so you don’t get false-positives.

If you are unsure about SparkChess for Windows, you can use the free VirusTotal.com service to upload and scan the installer. They scan with 70 different antivirus and antimalware programs .

If Norton Antivirus quarantined your download, please follow these instructions to restore it.

On Macs, SparkChess doesn’t need a special installer. There is no DMG or PKG file. When the download completes, Mac OS automatically decompresses the SparkChess zip file so all you need to do is to drag it from the Downloads folder to the desktop. Click here for a video.

Point-releases are free, i.e. if you buy version 9.0, you’ll get versions 9.1 through 9.9 for free, but not 10.0. Point-releases contain mostly bug fixes and improvements of existing functionality.

No. There are no monthly fees or subscriptions. Multiplayer access is free for the current version. If there’s a newer release than your version, multiplayer may or may not work, depending on the additional functionality we’ve added. We do our best to maintain backwards compatibility but we cannot guarantee it.

We certainly recommend you to upgrade, but the decision is up to you. Upgrading gives you access to new features and may correct any bugs we discovered. Also, as we improve and expand the multiplayer service, it may become incompatible with the older versions. The single-player experience never expires so you may continue to use the game for as long as you want.

We support major credit cards and PayPal.

If you have a Visa (including Electron and Debit), Mastercard, Maestro, Discover or JCB card, you can purchase SparkChess securely and easily from our site using the simple form. We also support prepaid cards. We do not store, transmit or process your card info – everything is handled by Braintree, our payment processor, a leader in electronic payments. If you choose this option, the name on the bank statement will be ‘SparkChess’. We do not support American Express this way.

Alternatively, you may use PayPal for payment. You don’t even need a PayPal account – you can use your credit card without logging in. PayPal supports Visa, Mastercard, American Express and Discover. If you pay with your card via PayPal, the name on the bank statement will be ‘PAYPAL*SPARKCHESS’.

So which option should you choose? PayPal is best if you have a PayPal account or if you have an AmEx card, otherwise paying with the credit card is faster, easier and just as secure.

We’re proud of SparkChess; we have tens of thousands of happy players since 2008 and we put you and your satisfaction at the top of our priorities. As such, we have a real Money Back Guarantee, which is highly unusual with downloadable games.

30 Day Money Back Guarantee: If you don’t like SparkChess or are unable to install and play it, we’ll give you a full refund. We only ask you to let us know what you didn’t like about SparkChess, or – if you can’t install/run it – to let us try to help you. This way we can get better.

If you bought SparkChess by mistake, or simply changed your mind, you can get a full refund within 14 days, as long as the game wasn’t downloaded. No questions asked. This is a EU requirement for EU citizens, but we’re extending it for everybody, no matter where you’re from.

If you bought the wrong version, for example you wanted the PC version but bought the Mac one instead, we’ll replace it free of charge, as long as you make the request within three working days from the purchase date.

This refund policy applies only for purchases from sparkchess.com. If you have purchased SparkChess from another online store like Apple AppStore or Google Play, you must request a refund from the store you purchased SparkChess from, subject to the store refund policy.

Yes, the payment process is perfectly secure. We are PCI-DSS compliant. We do not store, process or transmit any credit card info. The payment is handled by Braintree, a world-wide leader in electronic transactions.

The connection is secured with the highest-grade SSL encryption, rated ‘A’ by Qualys Labs and, as stated above, we don’t have access to the credit card info anyway. We only store your email and transaction ID, everything else is handled by Braintree.

We continually monitor and test our systems to make sure they are 100% safe.

SparkChess for Windows and Mac OS are not subscription-based and there are no recurrent charges for them.

SparkChess Premium Live is a subscription-based service that lets you play the full version of SparkChess in your browser. There are no automatic payments on SparkChess Premium Live. You buy a prepaid subscription for 1, 6 or 12 months.

At any time you have the option to extend that period with a new payment. Your card or PayPal account are not charged automatically, you never need to cancel the service. We believe this system is more honest and better protects your interests.

Yes! SparkChess has been used in schools and chess clubs.

If you represent a school (public or private), chess club or any other educational organization, we’d be happy to talk.

We can offer volume discounts, special private playing areas in multiplayer, even rebranding.

You can also manage members, assign them to teams, allow autologin, and much more.

Contact us and tell us about you and your specific needs!

Yes. There are no monthly fees. However, paying customers do enjoy extra benefits, including creating and managing teams, stats and history, private playing areas, unlimited number of daily games, unlimited score, priority access and more.

Here’s the list of multiplayer Premium benefits:

• Create and manage teams;
• Game stats to track progress;
• History / replay of all multiplayer games, with cloud sync across devices;
• Private playing areas;
• Unlimited number of daily games (free accounts are dynamically limited to conserve resources);
• Unlimited score (free accounts are limited to 2000 points);
• Priority access if the service is congested;

SparkChess uses an Elo-based scoring system. Elo may be a bit confusing for beginners but is well-understood by chess players and it’s used by chess federations worldwide.

The Elo system awards points based on which player is more likely to win based on the existing scores. Two players with equal scores should be equal in skill and are expected to win 50% of the time. In contrast, a player with a much lower score is expected to lose. Let’s use an example:

Player A has 2200 points and Player B has 1600. Based on the formula, Player A is expected to win 9 out of 10 games, so if he/she wins, there’s no big achievement and will be awarded just 1 point. In contrast, Player B is expected to win just 10% of the games, so of he/she wins, he or she receives 19 points. In fact, player B would receive 9 points just for a draw!

You can see how this system is fairer. Someone can’t accumulate score by playing only with other lower-ranked players. Also, scores don’t grow indefinitely, they tend to stabilize after a number of matches. Therefore, the best way to increase your score is to play (and win) against someone with similar score.

Here’s the formula we use:

where S’_A is Player’s A new score, S_A is Player’s A old score, S_B is Player’s B old score and R is the the game result: 1 for Player A winning, 0.5 for a draw or 0 for Player A losing.

Compared to FIDE’s formula, we use different factors: 20 instead of 15 so players get more points for each win and 700 instead of 400 so players get at least one point even when playing against weaker opponents.

We are parents ourselves and we’ve taken precautions to make SparkChess Multiplayer a fun and safe environment for kids. Children under 16 do not provide any personally-identifiable information and don’t have access to the Chat feature. We believe this is the safest way to ensure that they are not exposed to inappropriate language (filtering is done for English only). However, we cannot make any guarantees. We recommend parental involvement in all online interactions. If you notice anything offensive used in usernames or profile pictures, we encourage you to submit them to our attention.

Players are also able to block unwanted interactions with a block list.

Filtering the players by subnet will only show players connected from the same network – usually the same physical location. Use this option to have your children see only opponents from the same household or nearby area.

For schools and chess clubs we can offer a complete separate environment. Please contact us and let us know your requirements.

We do not tolerate bullying, cheating or any other abusive behavior. If you have knowledge of such actions, please report the user’s name and their behavior. We may penalize their score, ban them for a limited time or, in extreme cases, remove their account and ban their IP. At least once we banned an entire IP range. Your safety trumps any pursuit for profit.

In chat, you have a Report action button for the chat messages that you receive. We receive a copy of the message and determine the appropriate actions. For example, abusive players may have their chat privileges revoked.

You can also block annoying opponents and they won’t be able to invite you anymore.

Yes, if you can browse the web, you should be able to use the multiplayer service.

SparkChess uses websockets for multiplayer. This technology allows for quick, lag-free interactions between players. It is theoretically possible for it not to be available in some very restricted environment or maybe through the Tor network but we haven’t received any such report in 10 years.

SparkChess Multiplayer was designed to connect through firewalls. Generally speaking, if you can browse the web, you should be able to use the service.

Check the Server Dashboard – if it reports that it’s up and there are people connected, the problem is local.

• If you have the free online version, the most likely cause is that you’ve exceeded the maximum number of daily matches or that there are too many players connected (users of SparkChess Premium have priority).
• if you have the Premium desktop version, some Antivirus programs include overzealous firewalls that may block SparkChess. You must grant access for SparkChess to access the Internet via port 443 (SSL). If you’re unsure, temporarily disable any antivirus and firewall you may have installed and see if you can connect.
• if you have SparkChess on a mobile device, we noticed that DNS resolution seemed slower in some instances leading to timeouts in extremely rare cases.

Over 25,000 people use the SparkChess Multiplayer service every day. There are between 300 and 1000 players online at any given moment.

We have load-balanced live servers located in New York City with automatic  failover located in Seattle. We use Cloudflare for quick delivery, firewall and DDOS protection. We take daily offline backups. The quality of service is monitored 24/7 at 1 minute intervals.

Unlike many other MMO’s we do not take servers down daily or weekly. We apply rolling updates on the servers so that there’s always at least one server running at any time. We have 99.999% uptime and we’ve been this way since 2012.

SparkChess Multiplayer Service is powered by leaders in cloud services. We have load-balanced live servers located in New York City with automatic  failover in Seattle. We take daily offline backups. We monitor the service 24/7 at 1 minute intervals. We have an uptime of 99.999% (5 minutes of downtime per year).

If you get disconnected, the most likely cause is an instability of your internet connection – wifi issues, mobile data connectivity and so on. The multiplayer service requires constant connection and if the connection is lost for 30 seconds, you get disconnected.

Users who use torrent (or any other P2P) software may also experience issues, especially when there are many connected peers.

If you get disconnected, you can use the Multiplayer Service Status to see if the service is down. That page is updated every minute.

SparkChess attempts to automatically reconnect in case of a lost connection and resume the game. Cases where resuming fail are very rare.

Free accounts may be removed if unused for prolonged periods. From time to time we purge inactive accounts. The “grace period” is dynamic and calculated based on many factors. We do want to reward active users to conserve resources (storage is not free and having a few GB of unused accounts doesn’t help); we also need to backup the databases and maintain them, which requires more CPU power.

Accounts may also be removed without notice if they contain offensive names.

Currently the following filters are available:

• by score: with this filter enabled, only players within 10% of your score will be shown. So if you have 1000 points, you’ll see only players with at least 900 points and at most 1100 points.
• by subnet: The filtering is done by IP address. Only players with IP addresses from your “virtual neighborhood” are shown (technically speaking it’s a Class-C subnet). This usually means only players from the same building or block, although it depends on your Internet provider. This mode is perfect when you want to play with a coworker or at home with another person in the same house.
• by country: only players determined to be in the same country as you are shown. This method may not be always available. Players who’ve just created accounts may not have their country determined yet.

We should mention that your location (both the IP and the country) are safe. Another player cannot learn your location.

Yes, correspondence chess support has been added in 2024, in SparkChess 18. See the specific questions and answers for details.

Multiplayer games may end unexpectedly due to connection issues on your – or your opponent’s – side.

Since 2014, the SparkChess multiplayer service is having a measured uptime of 99.999% (that is 5 minutes of unavailability per year). Every day, about 10,000 people connect and anywhere from 30,000 to 50,000 games are being played. Frustrating as it may be, only an insignificant number of them end unexpectedly.

In general, a game will end abruptly when one player can communicate correctly with the server but their opponent can’t.  Unlike real-time FPS multiplayer games for example, chess cannot be fault tolerant. In a real-time game one player may miss one or more updates from the server and still keep playing (often the player sees the enemy “jump” from one place to another). But as chess is turn-based, players must be in perfect sync – one player can’t just move twice or ignore a non-responsive opponent!

A player may miss a server move due to many reasons: a bad internet connection or a browser bug are just some of the culprits. For example, Google Chrome can ignore a move received from the server if the browser tab is not active. Or a player may not be connected to the internet and not realize it as the system still reports it as being up.

If a player is disconnected, the SparkChess Multiplayer Service will attempt to reconnect automatically and resend any move that might have been missed, but this must be done within a certain time window as the opponent can’t wait indefinitely.

If you receive a message that the game is out-of-sync and it has ended, it usually means that there was a miscommunication between you, the multiplayer service and your opponent. Since 2018 we decreased the chances of an Out-of-Sync to negligible values.

If you lost any points due to a game ending unexpectedly, please contact us mentioning your username, your opponent’s username, the date & time the match took place and the number of points you lost.

We are continuously improving SparkChess in all its areas: the AI chess engine, the multiplayer service, the user interface, the additional tools and so on.

The multiplayer service is particularly sensitive because of the complex interactions and also because a small number of players will always try to cheat their way into the leaderboards.

Whenever we update the multiplayer functionality, we need to consider how two players with different versions will interact. To give you a very simple example, if one player has Chat capability but the other doesn’t, what do we do? Do we let the chat-enabled player send messages to the other one, even though those messages will never be received?

Most cases are more difficult, for example when a move needs to be resent due to a client disconnect.  Even more complicated, when we discover a way to stop cheaters, we may need to effectively ban all old versions.

We try to keep these breaking changes to a minimum and even then we give a few months of transition period, but we can’t support old versions indefinitely.

You can use the Gravatar service to add an avatar. Gravatar stands for Globally Recognized Avatar and it’s a free service from WordPress, the organization that maintains the WordPress software that powers over a third of the world’s web sites. Gravatar works by linking an email address to a public profile picture.

To add a photo, first you need to create an account:

• Visit www.gravatar.com
• Click on the big Create Your Own Gravatar button.
• A simple account sign up form will be shown. Enter the same email address you’re using with SparkChess and a password. When you submit the form, you’ll receive a confirmation email. Click the Activate Account button on the email.

Now that you have your account, go to gravatar.com again and login from the top right. After login, you’ll see a page with the title Manage Gravatars and the text “Whoops, looks like you don’t have any images yet! Add one by clicking here!” Click on the link and follow the instructions.

If you don’t want a photo, our own system will generate a random profile image for you.

After logging into multiplayer mode, you will be presented with a list of playing areas from which you must select (enter) one in order to play.

Playing areas are also called “lobbies” in multiplayer games. Simply put, they are virtual gathering places where players can meet and challenge each other. Playing areas can have some restrictions, for example, one of them is reserved for new players.

Upon entering a playing area, you will see a list of available players. When you click on a player’s name in the list, you invite them to play. Or you can simply wait until you are invited.

Multiple multiplayer accounts are allowed but not encouraged. We recognize that there are legitimate reasons for players to have more than one account. However, using multiple accounts to inflate your score or for other nefarious purposes is not allowed, and such accounts may be removed without warning.

When accessing the multiplayer service, there is an alternative “Guest login” option. We added this feature many years ago when we realized that some players wanted to get a taste of multiplayer without having to spend time setting up an account.

Note: Setting up an account is very straightforward, just enter your nickname, email (for password recovery) and password and you’re in!

Guest accounts are ephemeral. They start with 800 points and their progress is not saved. They have no stats or game history, they can not join or manage teams and have no access to chat.

Only use the Guest login if you are new to SparkChess and want to see how multiplayer works.

Now why in the world would you want to do that? Joking.

Short answer: It depends.

SparkChess Multiplayer requires WebSockets to connect. Sockets allow fast, near-instant communication and are used by most messaging apps and games. We used to support an HTTP fallback mode, but we removed it in 2018 because few players needed it and it lacked performance.

Back to VPNs, you need to check if your connection supports sockets. In our tests, we had no problems accessing the SparkChess website and multiplayer service via Tor and OpenVPN.

If you have problems with your VPN/Tor, you should disable it for SparkChess. We do not track our players and we do not block anyone. We are also not aware of any country blocking or tracking SparkChess.

Yes. We don’t rely on any closed platform for multiplayer or leaderboards and we own our entire tech stack. As such, users can play with each other regardless of the platform they’re on – PC users can play with Mac users, Android devices can play with iPhones, and so on.

The fastest and most secure way to delete your multiplayer account is from SparkChess. Select Challenge → Multiplayer, log in, select a playing area, click Account → Delete and enter your password for confirmation before clicking the Delete button.

The accounts are deleted immediately. If the deleted account was owning a team, the team is deleted as well. Leaderboards may take up to one hour to update.

Deleted accounts are generally not recoverable. If you deleted your account by mistake and are a premium player, we may be able to recreate your account, so please contact us.

The game history is not deleted.

Once an account is deleted, the username becomes available to be reused.

If for some reason you’re unable to access your account, please contact us with your username and request that we manually delete your account. Please note that we may need to perform extra checks to verify your identity.

Use the new Offline Challenge mode.

“Offline Challenge” is the name we chose for correspondence chess. You can read a detailed how-to on correspondence chess.

Over the years, both Apple and Google changed the permissions of the apps numerous times. As such, SparkChess had to adapt, sometimes restricting the options to import and export PGN files.

With SparkChess 18 for iOS/Android, released in 2024, PGN files and screenshots are available in the Documents folder.

Alyx is a customizable AI character that we created. Unlike the others like Claire or Boris, you can tweak Alyx to alter her strength and play style.

There are currently ten parameters that you can alter. We tried to name them intuitively so as not to bore you with chess engine implementation details. Here are the basic descriptions:

• Strength – this is the most important parameter. It specifies how many plies (half-moves) Alyx will think ahead. In some cases Alyx will think even more than this number, but this is the baseline. Increasing this value greatly increases the required time.
• Time – this is the allocated time per move. It can be as low as 1 second and as high as 4 minutes per move. It should be high enough so that Alyx has enough time to finish thinking. In other words, it’s not enough to increase strength, you should increase the time as well.
• Judgement – This parameter affects Alyx’ ability to evaluate captures and recaptures when thinking, in order to arrive at a ‘quiet’ position before evaluating the board. Chess engines call this quiescence.
• Accuracy – This is the accuracy in evaluating the board. Increasing this to 100% makes Alyx always perform the best move; lower values allow for more variation in play. Decreasing this will lead to spectacular blunders.
• Focus – You shouldn’t need to alter it too much. The impact on search is relatively limited. Lowering it can make most searches faster, with an occasional very slow one. Higher values will make search times more uniform. Technically known as ‘aspiration window‘.
• Aggressivity controls how ‘desirable’ captures may seem. A higher value doesn’t mean a stronger play!
• Memory – how much memory is allocated for ‘cache’ – remembering old positions. Higher values will improve search times, but only up to a point.
• Intuition controls the heuristic algorithms, helping Alyx remember previous moves that were very good/bad. Altering it will subtly change the behavior, but there’s no a specific direction that will increase the strength. You’ll have to experiment.
• Insight is important in discarding bad moves. Moving it all the way to the left will possibly lead to more accurate results since no move will be discarded in tricky situations, but will dramatically increase search times.
• Knowledge affects openings and determines how much Alyx will rely on her memorized opening lines.

If you find an interesting combination of parameters, please share with us!

Premium Live users may need to log in twice when using SparkChess:

The first step is to log in to the Premium Live service. Here, users must enter the email address they used to create the Premium Live account after purchasing a subscription and the associated password. Once logged in, they can play single-player or multiplayer.

Signing up for multiplayer is completely separate. Users log in to the Multiplayer service with an account created for this purpose, using a username (nickname) of their choice.

This system is necessary and by design. Premium Live users can have multiple multiplayer accounts, and a separate username protects their privacy by not revealing their email addresses.

For schools and chess clubs we have a management solution where one Premium account is associated with a multiplayer username and a team, so only one login is necessary. Contact us if you want SparkChess in your club or classroom.

Creating teams is only possible in SparkChess Premium (paid version).

1. Once you log in to multiplayer and enter a Playing Area, you’ll see the invitation window with a couple of buttons at the bottom. Click/tap on the Teams button
2. This will bring up a team list. At the bottom of the list there’s a Create button. Click/tap it. Note: The button is disabled if you’ve already created a team or joined an existing team. You must first leave a team to create a new one!
3. Upon clicking Create, you’ll be presented with a very short form. Just enter the team name, a description, and optionally the URL of a website (if your team has a website, Facebook page, Twitter page, or something similar). The time control settings are explained explained separately.
4. Click Save. Your form will be submitted for approval by the SparkChess team. Teams are usually approved in less than one business day. You cannot make any changes until your team is approved.

If you are the team owner, you can edit it just the way you created it.

1. Click the Account button in the Invitation window. Your Account Window will be displayed.
2. At the bottom of the account window you’ll see some buttons. Click on Team.
3. Now you’ll see your team page with the name, description and a list of existing (and upcoming) members.
   • Click on Edit to make changes. Once you click Save, the changes will be sent for approval. You cannot make any more changes until the existing ones are approved (this usually takes less than one business day).
   • Click Leave Team to, well, leave. Since you’re the team owner, all other team members will be removed and the team itself will be deleted. Note: this action is permanent – there’s no way to undo it!

For security and privacy reasons, players must personally ask to join a team. You can send them instructions on how to do this.

If you’re a teacher or chess instructor, please contact us. We have a platform where you can add users, assign them to your team, and more!

When users request to join your team, they must first be approved by you. To approve them, you’ll need to do the following:

1. Click the Account button in the invitation window. Your Account Window will be displayed.
2. At the bottom of the Account Window, you’ll see some buttons. Click on Team.
3. Now you’ll see your Team page, with its name, description as well as a list of existing (and pending) members.
   • Pending members are shown first, along with some brief statistics, highlighted and with two buttons next to them: a “check mark” for approval and a “cross” for rejecting.
   • To remove (“kick”) an existing player from the team, click on it on the list. A “cross” icon will appear. When you click it, the player will be removed from the team. Note: you cannot remove yourself in this way!

To join a team:

1. Once you’ve logged into multiplayer and entered a Playing Area, you’ll see the invitation window with a couple of buttons at the bottom.
2. Click/tap on the Teams button and a team list will appear.
3. Click on any team to see its details. Now you’ll see the team details, including stats and a list of members.
4. Click the Join Team button at the bottom. Your request will be sent to the team’s administrator for approval. It’s up to them to approve your request or not, but you can make further joining requests.

Note: If you make a new join request for another team, the old request will be deleted! You cannot belong to more than one team at the same time.

To leave a team:

1. Click the Account button in the invitation window. At the bottom of the account window you’ll see some buttons.
2. Click on Team. Now you’ll see the page of your team with the name, description and a list of members.
3. Click on Leave Team button at the bottom of the list.

All games played in your team’s play area will be subject to the team’s time control.

There are two types of time control:

• Time per move: this is simple and intuitive for new players. Players must make each move within the allotted time, expressed in seconds. So, if you enter “60” in the time control, players must make their move within 60 seconds.
• Total Time + Bonus time. This is how games in tournaments work. There is a total time for each player (in minutes) and an additional “bonus time” after each move (in seconds). So a time control of “10/5″ means that each player has 10 minutes to play at the start. They have to manage it – if they think too much on the first moves, there will not be enough time for later moves! After each move, the bonus time is added. Example: White starts with 10 minutes. White takes 30 seconds for the first move. White has 9’35” for the second move (10 minutes – 30 seconds thinking time + 5 seconds bonus).

Assuming you and a friend are now members of the same team, it’s time to play.

To play, you both need to be online and logged into multiplayer. Here are the steps:

• Log in to multiplayer mode, and you’ll see a list of Playing Areas. At the top you will see “My Team (visible to members only)”. All team members should enter it.
• The invitation window will be displayed. All available (currently online, not playing) players are listed here.
• Simply click on any player to invite them to play. From this window you can also watch the matches live as they happen.