May 20th, 2020

  • Blocking is no longer respected for Variant games (except teammates in teams games). The player pool for such games is too small, which leads to "discrimination" issues. (For example, some players block all strong opposition, effectively preventing the blocked players from getting a game started.)

May 19th, 2020

Recent changes

  • New Hyperbullet rating and leaderboard. This rating type covers any game with a hyper time control, eg the same rating is used regardless of the game being Solo, FFA or Teams, Antichess or other Variant.

  • New Settings, customizable square and wall colors.

  • Upcoming tournaments (click the Arena icon in the Play tab), are now filtered (by selected modes and time controls)

  • Rounded corners happy.png   including rounded corners for transparent walls (for 8x8 board etc)

  • New category filter for listed variants (click the List icon in the Play Tab).

  • Diplomacy games are now casual only

  • 1- and 2-check are disabled for standard teams games (solved win for R&Y). Does not apply to custom starting positions

  • Checked kings are no longer highlighted in the "Capture the King" variant.

Update April 2nd, 2020

  • Tournaments

    Check the Play Tab for ongoing and upcoming tournaments.
    You can also see ongoing and recent tournaments in Leaderboards->Tournaments

  • New design for games and tournaments

    Many thanks to @GDII for the new styles and tournament calculations!

  • New Page Layout with the main tabs having the full window height unless a game is opened. (non-premiums)

  • Client performance tuning
    - Faster painting of positions on the board
    - Move and other animations use native CSS transitions (was JQuery)
    - Initial page load optimizations (speed, direct access to game in url)
    - Other client optimizations

    This should help a lot for users on slower computers and mobile phones.

  • Players with a partner are excluded from blocking checks. You may face players you block as opponents in teams games (but never as your teammate).

  • Symmetric editing: In Edit Position, the option (under the board) allows creating and editing symmetrical positions quickly (edits are reflected for all players).

  • Fairy Pieces
    4PC now supports 21 different Fairy Pieces. Check the Edit Position tab.

    Sample game:

    Remember you can Shift-Click on any piece at any time to see its legal moves!


  • Any piece can be declared the Royal one, it need not be the king. Non-king royals are highlighted, as are royal kings when spare kings are present on the board. (Edit position -> More options -> Royal Piece (type in coordinates. "h2" ).
    Use keyboard shortcut 'K' to toggle the coordinate helper (mouse over squares), or 'L' to toggle the coordinates.

Update Jan 28th

  • Adjustments to ffa rating calc for large span games (like 2500 vs 2700 vs 1800 vs 1700, where the winner was gaining too much or not enough)

  • Support custom pawn base rank (from which pawns can jump 2 squares. They can also jump from the rank right behind it (for horde/war for throne type positions).

  • Support castling in a standard 2-player chess setup.  This setup combined with pawn base =5 11th=any, +play4mate is then regular chess, for which there is a new button in the Edit Position tab.

    4pc now offers new possibilities for regular chess variants, such as King of the Hill + 3check combined, antichess + KotHill combined, etc

  • You can create 3- and 2-Player games where one or two 'players' are zombies from the start. Zombie armies are controlled by a modified comfuter:
      - Rando: make random moves.
      - Ranter: on each move,  50% chance of playing either a random or a comfuter move
      - Comfuter: regular comfuter
      - Patzer: will play the worst comfuter move
      - Pusher: Pushers are Comfuters that will always push pawns if possible.
      - Checker: Checkers are Comfuters that will always check if possible.
      - Muncher: Munchers are Comfuters that will always capture.

    All zombies do not like to capture pieces of other zombies (except randos/ranters)

    In addition, you can set zombies to be immune, meaning their pieces cannot be captured. These are like moving walls, very powerful pieces!

Update 16 January, 2020

  • Switched to a simple and fast connection library, 4pc now handles sockets/rooms/observers itself. Hopefully connections will be more reliable and faster.

    You can now open 4pc in multiple tabs/windows. Shift- or Ctrl/Cmd- click on games (in the watch/archive list, or on 'Playing/Observing' in a player-popup or friends list) to open them in a new tab.

Rules changes:

  • FFA: 2nd place always gains, 3rd always loses rating. 2nd place used to be 2 wins and 1 loss vs average, now it’s X wins vs average (and no losses).
  • The higher the average rating of the game, the smaller the rating changes for 2nd and 3rd place will be.

    This is an attempt to discourage teaming from A-Z in high level FFA.

  • Doublechecks by Queens are worth +1 point only. otherwise +5. Triplechecks by Queens are worth 5 points, otherwise +20.

  • FFA/Solo: King captures take priority over checks or pins by the player whose king can be captured.

    After Green moves the Knight, Red can capture the Blue king (as long as Red is not in check by another player as well). Similarly if the red bishop were pinned by a blue piece, it would be allowed to capture the king.

  • Solo: Autoresign: If there are only two players left, and one of them cannot win (there aren’t enough points left to be made to reach 1st), the he is forced to resign. This prevents “king making” (deciding the winner) by a player who cannot win himself.

More changes:

  • New Game Modes:
    The quest for fun modes continues, especially for an FFA that not be so teamy.

    “+3” was inspired by Hest1805: checkmates/kings are worth 3 points (rather than 20). Resigned kings will sit still (no DeadKingWalking, as in the old days).

    When you checkmate a player, his pieces (but not pawns) join your army! If a player resigns, their pieces remain live (worth points, but don’t move) and can still be taken over by checkmating their wandering king.

    “Play-4-Mate” is a game where only checkmates matter. No points for pieces! And: the first to deliver a checkmate will win the game (+60 points), but further checkmates matter (+30 and +15 points for 2nd/3rd checkmate), a total of 105 points each game, and rating changes will correspond to how many points a player made. 105-0-0-0 is much like a solo win, 60–30-15-0 much like FFA.

  • Back to 1|15D default for Solo, time control settings no longer saved separately for solo/ffa/teams.

  • Support for 2- and 3-Player games: You can create 2- or 3-player games by creating a custom starting position where one or two players are dead. Thus these games can only be played casual, unless admins decide to list such games. The rating system now supports 2 and 3player games. They count as variants.

  • Team-engines:
    @Tony and @omatamix have each developed a 4-Player Teams engine, and can invite players to play against their bots: @TeamTerminator1&2 and @PhoenixZero1&2. Games may be rated as long as the same engine plays both sides of a team.

  • Faster updating of online friends, up to 200 friends checked.

    - Solo rating deflation.
    - Solo-antichess games ending when resigned army stalemates.
    - Discovered checks counting double in N-check Games. tons of fixes, improvements, and new features..

Update 8 October

  • +300 rating points have been added to all 4 Player Chess ratings. New players start from 1500.

  • Rapid and Blitz ratings have been merged. You have kept your rapid ratings unless your corresponding blitz rating was higher.

  • The New-Game dialog shows Solo alongside FFA and Teams to all players that have played at least 25 rated FFA games (or at least one rated Solo game). The default time control for Solo is 1|5 (1 minute, 5 second increment).

    (Solo is Free-for-All, but only the winner gains rating, 2nd-4th lose equally.)

  • Updated leaderboad requirements: 3 games played in the last 2 weeks.

    For Leaderboard champions: Standard leaderboards count double, point chase and most games played no longer count.

Rule Changes:

  • If the last man standing does not have sufficient mating material (eg, lone K, K+N or K+B), the points will be shared (+10 for both rather than +20 for the last man standing). Points for other remaining resigned kings will still be awarded to the last man standing.

    For some variants such as N-Check, King of the Hill, Capture the King or DeadWall, sufficient mating material is defined differently.

  • In case of 3-fold repetition, 50-move rule or insufficient material, points for remaining resigned kings will be shared (in addition to the +10)

  • Solo-Antichess: The game will end as soon as the first player stalemates (as 2nd-4th doesn't matter in Solo).

  • Adjusted abort timer: 10s for 1/2|0 games, 20s for 1|0 or similar.

Other notable changes:

  • Slight changes in definitions of bullet/blitz/rapid: 3|0 is now bullet, 2|2D and 1|4D are blitz, 3|5, 4|4 and 5|3 are rapid.

  • LAG compensation: the time it takes to receive the last move and send a new move back to the server is added back to the player’s clock. It should now be possible to premove several moves per second regardless of your connection speed (ping).

  • Fixed "Zombie effect": Players that had resigned kings to their right lost a lot of time on their clocks

  • Improved premove implementation

  • You can set a custom color for premove highlighting in the settings.

  • Antichess: opposite color bishop endings end the game (insufficient material)

  • Analysis board: 3-fold repetition is now detected in variations

  • Invite partner button in bottom left corner after closing game-over window (and for archive games)

  • If you click on ‘Playing’ in a player-popup or the friends tab, the board will be rotated to that player when the game loads. Same for ’Observing’ if the player played in the game.

  • Comfuters will move more quickly (3s max)

  • You cannot add or remove antichess rules from listed custom games. (You can, but you can't keep it rated)

  • Material balance for teams games now supports promotions and imbalanced custom positions. Queens are counted as 10 (and bishops as 4).

  • Nicer tooltips

  • Custom time control settings are saved by game mode (Solo, FFA, Teams).

  • You can create casual Solo games now.

  • Send message from player-popup opens dialog rather than a new window
  • Open Chesscom-Chat from player-popup (except while playing rated FFA or Solo)

Update 15 July

Rule Change:
• New FFA resignation mechanics: upon resignation or timeout, before the pieces turn grey, the king will try to make a (random) move. If he can't move, he will sit still. (So, a resigned king won't be stalemated right after a resignation. And he won't capture his own pieces to escape on that move. But on the next move he can capture grey pieces to escape, as it was earlier.)

Other notable changes:

• Fixed Teams rating range bug when accepting invites.
• Added Teams invite restrictions to prevent sandbagging abuse.
• In N-Check games, lives are now taken into account when checking for 3-fold repetition.
• Typing "33.", "24.b" or "move 29" in chat will create a link to that move, just like "#123456" will create a link to game 123456.


Update 21 May

Rule Changes:


New Features:

  • New queue and matchmaking: The Play Tab shows all queues. Players can join up to three queues simultaneously, and will play the first one that fills up.

    Before you join a queue, make sure you read and understand the rules! (see List of variants) Also pay attention if a game is rated or casual. As soon as 4 players join a game, it will start (and the 4 players leave other queues they joined). The number in the top left corner shows how many different players have joined at least one game (and will drop by 4 each time a game starts). The list is sorted by number of players joined, so games will rise up as players join. Games you joined will always be at the top of the list.

  • Players can create queues for any kind of game using the new play settings. (New Game -> Settings icon)

  • Players can host casual games (New-Game->Settings->make casual->Host). Hosting means you can invite players to your game (this is not a teammate invite), keep it private, and/or arrange the seating. if public, your username will show with your game in play tab.Players can also invite Comfuters and RandoBots to hosted games. (Admins can host rated games also).

  • New rating types and leaderboards for different time controls and variants. See for leaderboard requirements.
  • It's now possible to toggle the main tabs without exiting the room.

  • Click on 'Bots' in the Play Tab to play casual games with a mix of Comfuters, RandoBots and fellow humans.

  • Matchmaking supports blocking. Block/unblock via player-popup, also friend and follow. When you join a queue (or accept a team invite), you may get a message that your are blocking, or blocked by, players in that queue, and the game will disappear from the play tab. In case you joined via new-game->play, you will automatically be put in a new queue if joining an existing one got blocked.
    - You can't invite players you block or players that blocked you. (you can now close aka ignore invites)
    - Blocking currently has no effect on chat or anything else in the 4pc app.
    - If you are blocking (but not blocked by) players upon joining a queue, you are shown the username of the player(s) you blocked (so you can consider unblocking).

  • If you invite a teammate via the player-popup, your play-settings determine the kind of game the invite is for. same for inviting from the new game window.
  • If you invite your teammate via the game-over window, the invite will be for the kind of game just played.
  • You can invite to any teams queue on the list (with <3 players).

  • Added 2 new piece themes, 'Classic' and 'Alpha', see settings.

  • Added setting "Pieces face center" (rotated pieces)

  • Added setting for anonymous spectating. Obscures your username in spectator lists (unless you participated in chat). Your player popup will not reveal you are observing, the friends tab however will, to your friends only. Spectators are not anonymous to admins/staff.

  • Added setting to enable keybaord shortcuts. Arrow keys, "," (start) "." (end) backspace (takeback) and space (play comfuter move) are enabled regardless.

  • Added custom color settings. Note the application uses the terms "Red" "Blue" etc, so it is advisable to stick to similar colors. Not all colors will work well on all backgrounds.. adjusting panel transparency can help..

  • New replay/pause button to autoplay games

  • New Diplomacy Variant (inspired by @VAOhlmann)


Fixes and Improvements:

  • Solo = Solo Play = Solo Mode is a new name for WTA (Winner Takes All). It is FFA games with 1 winner only. (In usual FFA games there are 1 major winner and 1 minor winner.)

  • tons of small improvements and fixes.

  • DKW "2.0": resigned kings will insta-move (not only on next turn). This introcudes new moves such as Kh1-h2T (timed out and moved to h2), RS (resigned into stalemate, points will be shared), R# (resigned into checkmate, points given to player(s) that are checking (couldn't find a scenario where two players checking was not already mate before resigns, but in case it's possible, points will be shared between the checking players).

  • Lots of en passant fixes, including support for capturing two pieces in one move and other oddities (double stalemate in antichess for example, or detection of pins and discoverd checks)

  • Anonymous games: players will remain anonymous in chat and spectator list after being eliminated (until the game ends), with the following limitations: The player popup (archive, leaderboards, friends..) will reveal you are observing. If you enable anonymous spectator setting, only friends will be able to detect you are observing.
  • Move list expanding beyond window height
  • 4pc width adjusts when clicking the collapse icon in the left chesscom navbar


Update 22 January

  • Autoclaim will no longer happen when the remainig opponent is in 2nd place.
    As before, autoclaim only happens when claiming does not change the standings.
    See for details on autoclaim.

  • Fixed Antichess bugs related to en passant and 960 castling
  • Fixed “Casual” showing for old games 
  • Initial rating deviation lowered from 200 to 160
  • "?" behind rating means deviation > 100 (was >120) 
  • Allow setting 960 position number for casual games
  • Improved report-administration (for admins)




Update 13 January 2019:

  • Removed daily/weekly Leaderboard (suspected of causing frequent player disconnects every 10 minutes during leaderboard recalc).


Update 5 January 2019:

  • Added support for "Rated WTA3.0". This means the winner gets 3 wins, 2nd 1win and 1 loss, 3rd 1 loss, and 4th 2 losses (so contrary to regular WTA, 2nd and 3rd are not equal). We will add such games to the list, please try them and let us know how you like it (compared to regular WTA).
  • Fixed arrow/chat bug for alternative teammates
  • Fixed topgames sorting
  • Fixed antichess enpassant (capturing en passant is now compulsory)
  • There is a 'relaod game' link when it's your turn (below the board). This is in case the move you played didnt get registered, which unfortunately occasionally happens. This is much faster than reloading the window)
  • Added setting "Optimize for live-streaming" which prevents the window title from changing (it was reported this causes problems with certain streaming software). It also hides admin-function in the player-popup (for streaming admins/staff)


Update 17 December 2018:

  • Now there is only 1 winner in Top FFA games. If all 4 players in a FFA game are rated 1550+ the game is in WTA mode (Winner Takes All). There is 1 winner only.
  • Any player (including free accounts) can create custom games now.
  • Daily and Weekly FFA Leaderboards. The scores depend on points earned in FFA games.
  • New FFA chat rules. No move suggestions. No begging for points.
  • We have a lot of new chess variants now. Take a look at
  • FFA rating is calculated against an average opponent now. (More detailed description coming soon ...)
  • There is an additional palette for colorblind.
  • Block lists are respected for Teams games (except custom games).
  • Autoclaim (Auto Claim Win): Wins will be claimed automatically, but only if the claim does not change the current standings. There is no autoclaim in casual (unrated) games.
  • Enable Premove in settings. (Note: the premove will be played only after the animation of the last move has finished. You can change animation speed in the settings.)
  • Browser History. Use the browser back button to get back to recently visited games or archive searches. You can bookmark games and simple archive searches.
  • Up to 100 friends are checked for online/playing status. (previously 20)
  • There are lots of UI improvements, including material balance in Teams.




  • Chat won't scroll down automatically if you scrolled up to read.
  • participants of the game will no longer accidentally be joined as a "spectator that can play". Instead they will be reconnected to the game correctly.
  • the game start animation time (~3.5s) is no longer deducted from Red's clock




Update 25 Sep

  •   "Create friendly games" is now available to premium members that have opted into beta ( Only the creator of a friendly needs premium, anyone can be invited.

  •  New friendly variants include N-check (each player has N "lives", the final check is checkmate), King of the Hill, and 960, or any combination of those! You can also set a custom starting position.
  • Country flags, online status (green/orange square indicator in avatar), full name and best rating in user popup (hover over username)

  • Integrated club chat.

  • You can no longer set your rating range to exclude players within 100 points of your own rating


Bug fixes:
 Observers (no more 'unknown')
 Team rating range when inviting



Update 13 Sep

 - reintroduced cancelling game if not all players connected at game start.
 - fixed low time sound? (please report if you have sound problems. it's browser dependent)

Update 12 Sep
- removed cancelling games because some players got stuck in them.
- changed shortcuts for blindfold and ghost board to SHIFT-B/G
- introduced low time sound bug?



11 Sep 2018 Released all features of the new version.

Rule Changes

  • To appear on the leaderboard, you need to have played 3 games in the last two weeks. You also need to have played at least 25 games total (since Aug 7 release). At the time of release we only have the date of your most recent game, and this game will count as 3 until it "expires" (is >14 days ago).

  • FFA rating changes have been increased.

  • You can no longer set your rating range to exclude players weaker than your own rating + 100.

  • The rating loss for causing an abort depends on how frequently you have aborted games. Very frequent aborting will result in a temporary play-ban.

  • Each player must make their first move within 30 seconds (before 0:45), or the game will be aborted.

New features

  • Game archive: all games (since aug 7 release) can now be found in the archive. Click the + on the far right of the search form to get more search options (2nd player, result (of first player), custom time span. The results can be sorted by date, number of moves (plies), or duration.

  • Analysis board (Keyboard shurtcut: A, or click New Game and choose Analysis board from the dropdown). The game replayer can also be used for analysis.

  • PGN4: save and share your lines, variations and annontations.

  • Edit position: Set up any position and “continue from here”. Save and share positions with FEN4.

  • Rematch: If all players click the rematch button, a new game will start with random seating (for teams, the other team will get Red).
    Note: the Rematch button is only available as long as all 4 players remain in the room (eliminated FFA players usually leave the room before the game ends). The number on the button indicates how many players want to rematch.
    EDIT: do to problems with the observers this feature is currently not likely to work.

  • Report abuse: report form accessible via the ! icon in the player popup.

  • Separate rating range setting for Teams and FFA.

  • Fullscreen/Focus mode: collapse the board panel. shortcut: F, or click the collapse icon (next to settings icon).

  • You can drag or select a piece before it's your turn and drop it once your turn is reached. Dropping before your turn will cancel the drag. (right-clicking will now also cancel the move.)

  • Drag the panel divider (just below the |< << < > >> >| buttons) to change the space available for moves vs chat.

  • Games you visited are slighlty dimmed in the list (top games and archive). Reloading the page will reset "memory"

  • Go back (to the last game you opened) -icon (located in same place as the exit-button)

  • Use the link icon (top right) for a link to the current game.
    - link to game and move (game #123 at ply 45. -ply is optional)
    - link to archive search

  • Rotate the board (compass-icon above moves list, shortcut R)

  • Automatically rotate the board to the player who's turn it is. (icon next to compass. shortcut T)

  • Settings are now saved in your account (used to be saved in browser)

  • Transparent arrows (shortcut W)

  • Piece animation speed setting
  • Panel transparency setting
  • Blindfold mode (Shortcut Shift+B)

  • Colored moves (shortcut M): colorful indications in the moves list of which and whose piece was captured or who was checked/mated.

  • Profanity filter

- MS Edge bug
- phantom piece bug
- layout for safari10
- top games sorting



  • Help page (shortcut H)

ⓘ Shift-clicking any piece show's it's legal moves.

Keyboard shortcuts:

← → ↑ ↓
, (comma) Start
. (dot) End
Backspace/Delete Takeback

Escape Exit Room/Game
A Analysis mode
S Settings
H Help

R Rotate board
T Auto-rotate <font data-v-fe1f2c4c="" size="-2">(by turn)</font>
F Focus mode <font data-v-fe1f2c4c="" size="-2">(collapse board panel)</font>
L Coordinates
K Coordinate-Helper (show coordinate on mouse-over-square)

W Transparent arrows
M Colored move annotation
Shift-B Blindfold
Shift-G Ghost board (bug turned feature wink.png )

Right-click-drag to draw arrows.

Choose arrow color by holding key 1, 2,
3 or 4 pressed on your keyboard.

Click the board to clear all arrows.

Shift-click to clear only your own arrows.

In games you played in, your arrows are
shared (and are of your color) when you
are not alone in the room.

In analysis mode (shortcut A), you can
change the game type, and edit player names,
ratings or points by clicking on them.
Alternatively, edit the PGN4 and press ↑ Load.

Please consider going premium to get the max out of these new features by freeing up the ad space for them! Support Four Player Chess! Thanks!





07 Aug 2018 A new version of 4PC (beta) released.


Changes in the game rules:

  • Checking three players simultaneously: +20 points.
  • A king can now capture resigned kings.
  • Resign or timeout in FFA: If a player resigns or times out before having made at least 4 moves, he will lose rating (-10 points currently) and the game will be aborted.
  • Resign or timeout in Teams Mode: If a player resigns or times out on his first move, he will lose rating (-10 points currently) and the game will be aborted.


New features and improvements:

  • Glicko rating system (instead of ELO).
  • Colorblind mode. (Red pieces become white. Green become black.)
  • Early resign or timeout leads to the game being aborted, and the resigner loses 10 rating points.
  • There can be a draw in Teams Mode games now.
  • A pop-up box with player rating and other information.
  • Legal move indicators.
  • Shift+click any piece to see its legal moves at any moment.
  • A button to invite the same teammate again in the Teams Mode. (Rematch with the partner you just played with.)
  • Captured pieces are now displayed.
  • Shift+click on an empty square to clear only your own arrows.
  • Clearing your arrows also clears them from your partner's (and observers') boards.
  • Observers can draw (orange) arrows for themselves.
  • It is possible to draw arrows after a game.
  • Single square arrows are shown as circles.
  • An option to hide teammate's arrows.
  • An option to hide coordinates.
  • A dot in the center of the FFA board to help find the squares where pawns become queens.
  • (a dozen or more of minor improvements like new sounds, visual effects, etc.)


More info with screenshots:


P.S. Old changelog:


Give u guys a thumbs up! thumbup.png


any possible way we could offer ffa 4 player tournaments?


4 Player Chess was updated today Sep 25, 2018. See the 1st message of this thread for the list of changes.


4 Player Chess was updated today December 17, 2018. See the 1st message of this thread for the list of changes.


Amazing! Thanks for your work


Finally my opinion is applied!
Wishing to reduce the elo limit of this rule from 1550 to less. 

  • Now there is only 1 winner in Top FFA games. If all 4 players in a FFA game are rated 1550+ the game is in WTA mode (Winner Takes All). There is 1 winner only.


PS: Just yesterday, I have seen a 1550+ player actually has no idea what the chess is. His standard chess rating is 900-1000. He is unable checkmate his opponent with many pieces. But he got 1550+ just by taking 2nd places.

2nd PS: I was extremely pissed off by this and wanted to quit the game for a while, until next update and surprisingly, the update that i have been wanting for so long time is out! TNX




updated Jan 5 2019


updated Jan 22 2019


unfortunately new queue is not behaving as it should. there's an obvious problem with 'games starting' but they don't start.


i'm working on it


Excellent changes! I am looking forward to playing my first game with these new rules! Thank you developers.


I would like to stay in the old chat when I search a new game, thanks!


@theladwholovednoone ty!


@nutsyci noted.

just click the ->| to get back to chat

here or here

spacebar wrote:

unfortunately new queue is not behaving as it should. there's an obvious problem with 'games starting' but they don't start.


i'm working on it

i think it's fixed, the play tab is looking much better now.

nutsyci wrote:

I would like to stay in the old chat when I search a new game, thanks!

changed behavior to not switch to play tab when clicking 'play this game (again)'. but it will still switch to play tab when clicking 'new game'



enpassant must be very bad , the game at the moment is very favourable to red/yellow this even help then more when i do not have defence like h4 g5


updated 3rd time now since release, with more fixes and improvements.

plus new setting added: "pieces face center"