Timers, clocks, and timezone math.

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

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

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

Precise stopwatch with lap tracking and millisecond accuracy.

Track the current time in multiple cities at a glance.

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

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

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

Convert times between any IANA timezones with DST awareness.

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

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

Work in focused intervals with automatic break scheduling.

Two-player chess clock with Fischer increment and Bronstein delay.