Chess Clock
Turn your smartphone into a chess clock. Free web timer supporting sudden death, Fischer, and byoyomi modes
How to Use
- Choose a preset or customize the time mode (sudden death, Fischer, byoyomi) and main time
- Place your smartphone between two players (the top display rotates 180° to face the opponent)
- The player on the far side (or opponent if you move first) taps their side to start the game
- After making a move, tap your side to pass the turn to your opponent
- Beep and vibration alerts count down remaining seconds; time's up displays a loss
Use Cases
- Managing time during shogi, Go, or chess games
- Preventing one player from taking too long on board games (e.g., 60 seconds per move)
- Playing games during travel or outings without a physical clock
- Serious practice games with byoyomi (e.g., 30 seconds × 3 periods)
Frequently Asked Questions
What's the difference between byoyomi and Fischer mode? ▼
Byoyomi is used in shogi and Go: after your main time runs out, you have a fixed number of seconds per move (e.g., 30 seconds) to keep playing. Fischer mode, common in chess, adds time to your main time with each move (e.g., 2 seconds per move). This tool supports both modes.
Will the screen turn off during play? ▼
During play, the Wake Lock API prevents automatic screen sleep. For browsers that don't support Wake Lock, please increase your device's screen timeout duration.
Who taps first—the player moving first or second? ▼
Like a physical clock, the second player taps first to start the first player's clock. If you move first, ask your opponent to tap their side (the startup screen also displays this hint).
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