For support and questions about SparkChess or chess in general, please see the links on the right and the Q&A section below.
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 Full Version, you have access to some help tools that will help you make better moves.
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:
- Open the game and start a new single-player game against any of the AI opponents.
- Click on the SparkChess logo at the top-right (top-center on mobile phones). An “About Window” will open.
- 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.
iphone, etc.); the third is the type (
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.
You can also join a local chess club. Also, iChess.net has many chess video courses available.
Playing Chess Online
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 the 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 MaxCDN 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 are now experimenting with 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 8 minutes apart.
SparkChess requires a modern browser to play online. Supported browsers include:
- Internet Explorer 10+
- Edge Browser
- Firefox 21+
- Google Chrome and Chrome for Android 46+
- Safari and iOS Safari 6+
- Opera 15+
- Android Browser 4.4+
- Blackberry 10
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 was the first online chess engine, first released in 2002 as flashCHESS and then rewritten from scratch in 2008. It was created with Flash (first Actionscript, then AS3 language) because at that time there simply were no other technologies available (except for Java applets, which were universally despised.
As time progressed, standard web technologies caught up with Flash and in 2015 we were finally able to make SparkChess a web app using the latest open technologies (HTML5, CSS3, ES5, Canvas, WebGL, Web Workers).
Now Flash is being pushed out by all browser vendors so we just can’t support it either. The Flash version is no longer supported and multiplayer is probably not working properly anymore. We are really sorry for the inconvenience and we wish there was something we could do.
In August 2016, Google revealed their plan to move away from the Chrome apps platform over the next two years.
This is their roadmap for Chrome apps (extensions are not affected):
- “Late 2016”: new apps are available only for people using Chrome OS. Existing apps are unaffected.
- “Second half of 2017”: Users with Windows and Mac OS computers can no longer install new Chrome apps. Existing apps continue to work.
- “Early 2018”: Users on Windows and Mac OS will no longer be able to load Chrome apps.
As such, you should stop using the SparkChess Chrome Web Store app as soon as possible and instead simply play the game on sparkchess.com. The functionality is identical to the Chrome Web Store app. You can bookmark the page by clicking on the ☆ star on the right of the URL bar or by pressing CTRL+D.
Even if you’re using Chrome OS, we still recommend you to play SparkChess on sparkchess.com as we won’t update the Chrome version as often and by 2018 we may retire it completely.
Downloading and installing
Yes. SparkChess is available as a standalone application on many platforms.
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 / Cortana (press
WIN+S) to search for “sparkchess”.
If youstill 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/CMD+J from your browser to see the Download History and look for a file containing the word “sparkchess”, e.g. sparkchess10setup.exe on PC or sparkchess10.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”.
Given the number of operating systems and devices SparkChess is available on, we’re trying to find the best match for you automatically. If you are on PC or Mac, you’ll be directed to buy the native app for your platform. We do not have a Chrome app, but we do have a Premium Live version of SparkChess that works in any modern browser, including on mobile phones and tablets. Go to the SparkChess Premium Live site to sign up.
If you have already purchased SparkChess for Windows or Mac and want it exchanged with Premium Live, please contact us.
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, overzealous antiviruses may very rarely flag SparkChess and move it to quarantine. (Sometimes, antiviruses manage to actually label themselves as viruses.)
SparkChess 8 was briefly flagged by Norton Antivirus as ‘WS.Reputation1‘, which basically means a file not commonly downloaded (new release – duh!). We’ve worked with Symantec and whitelisted SparkChess 8. 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 57 different antivirus and antimalware programs – SparkChess is clean and virus-free.
If Norton Antivirus quarantined your download, please follow these instructions to restore it.
On Macs, SparkChess doesn’t need to be installed. 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’.
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.
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, Google Play or Blackberry World, 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 PayPal company and 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 X are not subscription-based and there are not 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 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. There are no monthly fees, no subscriptions and no in-app payments.
Yes. Paying customers have priority access to the service, are able to use the Chat feature and can access private areas. Free users can play only if the server capacity is below a certain threshold and have limitations on the number of games they can play daily. There are many other subtle differences, for example a free user account has a score cap of 2,000 points.
SparkChess uses an Elo-based scoring system. Elo may be a bit confusing for beginners but it’s 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 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 have this 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, SA is Player’s A old score, SB 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 13 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 any online multiplayer game. If you notice anything offensive used in usernames or avatars, we encourage you to submit them to our attention.
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 nickname 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.
Yes, if you can browse the web, you should be able to use the multiplayer service.
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 80 (HTTP) or 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.
SparkChess Multiplayer is built using Union Platform by User1 and hosted by leaders in cloud services. We have load-balanced live servers located in New York City with automatic failover located in Atlanta and DDOS filtering. 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 99.99% uptime.
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 Atlanta. We take daily offline backups. We monitor the service 24/7 at 1 minute intervals. We have an uptime of 99.99%. You can check the public uptime stats.
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.
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 and we need 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 if they contain offensive names.
Because the number of available players is changing constantly, Full Version owners may filter the Invitation list based on their preferences.
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.
We have added Connection Quality Indicators for the multiplayer service. At this time they are experimental and are shown at the bottom of the Invitation Window.
They look like this:
From left to right, here’s what the icons mean:
- The bars show the network latency (also known as “ping time” or “round-trip time”), which means the amount of time needed for information to travel from your device to the SparkChess multiplayer servers and back. 4 green bars indicate a fast and stable network connection, while 1 red bar shows a slow and potentially unstable one. The number of bars you get depend on your physical location (users in North America are more likely to get 4 bars) and connection type. A laptop Ethernet connection will always be faster and more stable than a slow 2G cellular one.
- The Socket icon indicates whether your connection is through a web socket or by HTTP fallback. A green socket connection indicator means there’s a dedicated communication channel open between your device and the SparkChess multiplayer server. They are very fast but if the connection breaks due to your internet connection, you may get quickly disconnected from the server. HTTP fallback is much slower; it may not be affected by intermittent issues but this also means it may not detect immediately when your network is down. 93% of the connections to SparkChess are made via socket connections. HTTP fallback is used only if, due to peculiarities of your network, a socket connection cannot be established.
- The Lock icon indicates an encrypted connection. If you play SparkChess online through a secure HTTPS connection, the connection to the multiplayer server is required to be SSL-encrypted as well. Otherwise we don’t encrypt connections because encryption slows down the communication a bit. Given the nature of a multiplayer chess game, we believe encryption is not necessary. If you think we should always encrypt connections, please let us know.
A game may end unexpectedly in Draw if your opponent is unresponsive and, despite being online, did not receive the move in time (you should see the message “Sending Move” for some time before this happens). A player can be unresponsive for many reasons, including a network issue on their side or an old device.
The Multiplayer service cannot “punish” your opponent by declaring you the winner and can’t know if a Draw suits you. If you are unhappy with the result, please contact us mentioning your username, your opponent’s username, the date & time the match took place and the number of points you lost.
Multiplayer games may end unexpectedly due to connection issues on your – or your opponent’s – side.
The multiplayer service has an uptime of 99.99%. On any day, about 10,000 people connect and anywhere from 30,000 to 50,000 games are being played. Frustrating as it may be, only 1% 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 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 version 10.8.7 we made sure you don’t lose any points in this case.
If a game ends unexpectedly in Draw, it’s because your opponent is unresponsive and, despite being online, did not receive the move in time (you should see the message “Sending Move” for some time before this happens). The Multiplayer service cannot “punish” your opponent by declaring you the winner and can’t know if a Draw suits you.
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.
SparkChess uses a chess engine developed in-house with negamax, principal variation, iterative deepening, aspiration, quiescence, killers, history heuristics, null moves, razoring and transposition tables. It has an opening database with about 15000 moves.
The original version took about three months, not including the time spent studying algorithms. The game is in active development since 2008. We make one major release each year and a few minor releases.
We’re listening to feedback from all players and add the features you want the most. Our goal is to make people think “Chess is Fun!”. If you have any feedback or ideas for improvement, just contact us.
We believe the new fixed board design introduced in SparkChess 10 improves contrast and presents a more elegant chess set.
we commissioned a professional survey. 400 respondents living in the US, from all walks of life, were asked if they preferred the old or the new design. The new design won categorically, 62% vs 38%. The margin of error of the survey was 5%.
SparkChess uses iTunes to add, save and delete PGN files from your iPhone or iPad.
On iOS, each app has its own separate Documents Folder. The files saved in those folders are accessible by iTunes. SparkChess can import and export PGN files to its own folder.
To add PGN files on your iOS device or to save a PGN file from the iOS device to your computer, open iTunes, click on the iPhone/iPad button at the top to connect to your device, then click on Apps. From the Apps tab, look at the File Sharing section. There are two panels there. Choose SparkChess from the left panel; on the right panel you’ll see SparkChess’ Documents (if any). To add a new PGN, click on “Add File…” button and select a PGN file from your computer. To save a file from the iOS device to your computer, select a PGN from the right panel a click on “Save to…” button. To delete a PGN file from your iPhone/iPad, right-click on the desired file from the right panel and choose Delete.
When you’re done, don’t forget to click on the Sync button at the bottom of the page!
In SparkChess, click on Replay and then on the Import or Export icons to load and save PGN files in the game’s Documents Folder.