A daily puzzle
A new position every day, and a streak to keep. Solve the puzzle or play one game and the streak goes on.
Now on the App Store and Google Play
Ouk ChaktrangCambodian chess, on your phone.
អុកចត្រង្គ
Play the game Cambodia has played for centuries — against six bots, a daily puzzle or a friend online. The real Khmer rules, in Khmer and English.
Free on the App Store and Google Play
- Free
- No ads
- Plays offline
- No account needed
- Khmer & English
Play in your browser
Try Khmer chess right now.
No download, no account. Play the bot at two levels with the real Cambodian rules — every legal move lights up, so you learn as you go.
Play nowor get the app for all six levels
What's in the app
Khmer chess, wherever you are.
Play it, learn it, get better at it. Everything runs on your phone, so the board comes with you — on a bus, on a plane, or to a village with no signal.
Play a bot · offline
Six opponents, from Novice to Grandmaster
The engine lives on your phone, so a game never waits on a network. Start at Novice to learn the pieces; come back for Grandmaster when you think you are ready.
- Rated from 800 to 2400 — each level looks further ahead and blunders less.
- 15, 20 or 30-minute clocks, or play without one.
- The app points you at the level closest to your own rating.
Learn the rules
Every piece explained, in Khmer and English
New to the game, or only ever played international chess? The app teaches the parts that are different before they cost you a game.
- A page for each of the six pieces, with its moves drawn on a board.
- The counting rule and both first-move privileges, explained.
- Long-press any piece during a game to open its page.
Play a friend online
Open a room, send the code, and play. The server keeps the clock, so nobody's phone decides who ran out of time.
No account, no network
Bots, the puzzle, your streak and the board all work without signing in. A free account adds online play, a rating and the leaderboard.
ការលេង · How to play
How to play Ouk Chaktrang
Same 8×8 board as chess, six characters you have not met. If you play international chess you already know most of this — the three parts below are the ones that are actually different, and the ones the app follows Cambodian sources on, not engine convention.
Keep the guide handy: Khmer chess rules, pieces and counting.
01
How each piece moves
Six piecesខុន
KHUN · The king
One square in any direction — the chess king, minus castling. Once per game it may also leap; see 03.
នាង
NEANG · The lady
One square diagonally, and that is all. There is no queen in this game — she is the weakest of the officers.
គោល
KOUL · The general
One square straight forward, or one square on any diagonal. Never sideways, never straight back.
សេះ
SEH · The horse
The chess knight, unchanged — the one piece that reads the same in both games.
ទូក
TUK · The boat
Straight lines, any distance, no jumping — the chess rook, and the strongest thing you own.
ត្រី
TREY · The fish
StepCapture
One step forward, captures diagonally. They start on rank 3, not rank 2 — that extra rank changes every opening.
02
The counting rule
ការរាប់A game that runs down to bare pieces is not left to peter out — it is settled by counting. Once a side is reduced to three men or fewer, that side may claim the count and says a number aloud on each of their own moves. If the limit is reached before checkmate, the game is a draw. A winning position can slip away simply because you were slow.
First · ការរាប់ក្តារ
Counting the board
The ordinary case. The counting side starts at one and has sixty-four moves. Reaching the number draws — the stronger side does not get a move at it.
Then · ការរាប់គ្រាប់
Counting the pieces
Once the counting side is down to its ខុន alone and no unturned ត្រី is left anywhere, the count starts instead from the number of men on the board plus one — and the limit comes from what the stronger side still has.
The limits · moves allowed
- ទូក ×28
- ទូក ×116
- គោល ×222
- សេះ ×232
- គោល ×144
The first line that matches is the one that applies; anything else is 64. Where sources disagree, the app follows the Cambodian statement of the rule.
03
First-move privileges
Not like chessOnce per game
The ខុន's one leap
The leapNormal step
From its home square the ខុន may jump once like a សេះ, onto the next rank only, and never to capture. You lose the right the moment it has been checked — or the moment any piece is taken, by either player.
First move only
នាង's two-square opening
The openingNormal step
On her first move only, the នាង may go two squares straight forward — the one time in the game she leaves the diagonal. It ends with the first capture too, so the two openings are really one decision.
Rank 6, not rank 8
ត្រី turns over
Rank 6
Reaching the sixth rank, the fish is flipped over — not replaced — and plays as a នាង for the rest of the game. It is still a ត្រី, and the rules book is emphatic about the two being told apart.
Also not here
No castling. No en passant. No queen. If a rule looks missing, it is missing on purpose.
The fastest way to learn is to play.
Start against the Novice bot — it forgives mistakes while the rules sink in.
អំពី · About the app
Built for the game, not for the store.
Rules from Cambodian sources
Where the rules are disputed, the app follows Cambodian sources — a printed Khmer rules book and a Cambodian teacher's lessons — over the conventions built into international chess software.
Never real-money gaming
No advertising SDK, no third-party analytics SDK. The in-game coin (កាក់) has no monetary value, cannot be bought or cashed out, and cannot be wagered against another player.
Khmer is not an afterthought
The whole app is bilingual, and Khmer is set in a Khmer typeface throughout — never bolted onto an English layout, never a Latin fallback.
Who makes it
Ouk Chaktrang is built and published by Yean Seyha. For anything at all — a bug, a rules disagreement, a deletion request — write to support@yeanseyha.dev. Read the privacy policy for exactly what is collected and why.
What is Ouk Chaktrang?
Ouk Chaktrang (អុកចត្រង្គ, also spelled Ouk Chatrang) is Cambodia's traditional chess, often called Khmer chess. Like international chess it descends from the Indian game chaturanga and is played on an 8×8 board, but with its own pieces, a counting rule that settles endgames, and two special first moves.
How is it different from international chess?
There is no queen: the Neang moves one square diagonally. The Trey (fish) start on the third rank and turn over on the sixth. There is no castling and no en passant, and a game that runs down to a few pieces is settled by counting rather than played out forever.
Is the app free?
Yes. There are no purchases and no ads. The in-game coins cannot be bought, cashed out or wagered.
Do I need an account or an internet connection?
No. The six bots, the daily puzzle, your streak, the board and the clock all work offline without signing in. A free account is only needed for online play, the leaderboard, a rating and moving your progress to another phone.
Is Ouk Chaktrang on Android?
Yes — Ouk Chaktrang is free on Google Play. The iPhone version is on the App Store.
Can I play in Khmer?
Yes. The whole app is bilingual — switch between Khmer and English in your profile. Khmer is set in a Khmer typeface throughout and never falls back to a Latin one.
How does the counting rule work?
When one side is down to three men or fewer, that side may claim the count and counts aloud on each of its own moves. If the limit is reached before checkmate, the game is a draw. The limit depends on what the stronger side has left — as few as 8 moves against two Tuk.
What are the pieces called in Khmer chess?
Each side has sixteen men of six kinds: Khun (ខុន, the king), Neang (នាង, the lady), Koul (គោល, the general), Seh (សេះ, the horse), Tuk (ទូក, the boat) and Trey (ត្រី, the fish). There is one Khun, one Neang, two each of Koul, Seh and Tuk, and eight Trey.
Can I play Khmer chess online with friends?
Yes. Open a room in the app, send the room code to a friend, and play on the server's clock. Online play needs a free account; playing the bots does not.
Play Ouk Chaktrang today.
Free on iPhone and Android, with no ads and no account needed.