What is the difference between Fischer and Bronstein increments?

Fischer adds the full increment to your clock every time you make a move — your clock can gain time if you move faster than the increment. Bronstein only refunds the time you actually used on the move, up to the increment, so your clock never grows beyond the base time.

Does "5|3" mean 5 minutes plus 3-second Fischer increment?

Yes. The notation is base minutes | increment seconds. 5|3 is five minutes base time with a three-second Fischer increment per move.

Will the clock drift if I background the tab?

No. Each frame calculates elapsed time from a Date.now() delta, not by counting ticks, so browser background-tab throttling cannot desync the clock.

Why does tapping my own clock hand the turn to my opponent?

That is the standard convention for physical and digital chess clocks: you press your side of the clock to stop it and start your opponent’s. This tool mirrors that behaviour.

Chess Clock

Two-player chess clock with Fischer increment, Bronstein delay, and classic time controls.

Time control

Base (minutes)

Increment (seconds)

Mode

Countdown Timer

Set a timer for any duration. Get an alert when time is up.

Stopwatch

Precise stopwatch with lap tracking and millisecond accuracy.

Timezone Converter

Convert times between any IANA timezones with DST awareness.

Pomodoro Timer

Work in focused intervals with automatic break scheduling.

World Clock

Track the current time in multiple cities at a glance.

Unix Timestamp Converter

Convert Unix epoch timestamps to dates and back, in seconds or milliseconds.

Age Calculator

Calculate exact age in years, months, days, hours, and seconds.

Date Calculator

Add or subtract from a date, or measure the duration between two dates.

Interval Timer (HIIT)

Run work/rest intervals for HIIT, Tabata, and circuit workouts.

Alarm Clock

Set multiple alarms with labels, audio, and desktop notifications.

Meeting Planner

Find the best meeting time across timezones on a 24-hour overlap grid.

Sunrise & Sunset

Calculate sunrise, sunset, twilight, and golden hour for any location.

Time control

More time tools