Clock methodology

ChessClock.now derives the clock display from monotonic elapsed time, applies the selected bonus after each move and runs its chess AI on the player’s device.

How the clock and game tools work

How the timer stays accurate

The clock measures elapsed time with the browser's monotonic performance timer and derives the display from timestamps. It does not assume that a one-second JavaScript interval will remain punctual when the browser is busy.

Increment and delay

Increment is added after a completed move. Simple delay protects the configured opening seconds of each turn before the player's main time begins to fall. The settings keep bonus type and bonus seconds visible together so both players can verify the control before starting.

What the local AI does

The AI validates legal moves, evaluates material and activity, then searches between one and four plies depending on the chosen difficulty. It runs on the device within a browser-safe node budget. Difficulty names describe relative settings on this site, not calibrated Elo ratings.

Games and temporary rooms

A finished guest game stays in that browser. Signed-in players may save the result, control, duration and move count to their private dashboard. Invite rooms and their chat messages expire automatically after six hours and are excluded from search.

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