Time & date tools
8 free tools, all running in your browser. Timers, countdowns, date arithmetic and timestamp conversion.
- Countdown TimerPick a target date and time to see a live countdown in days, hours, minutes and seconds.
- Add or Subtract Days from a DatePick a start date, choose how much time to add or subtract, and read the resulting date and weekday immediately.
- Pomodoro TimerWork in focused 25-minute sessions with short breaks in between; the timer switches automatically and beeps when each session ends.
- StopwatchA precise stopwatch with lap tracking — press Space to start and stop, L to record a lap.
- Time calculatorAdd or subtract durations and measure the time between two clock times — results update as you type.
- Time Zone ConverterPick a date, a time, and a source city, then add target cities to see the converted local time in each one.
- Week NumberThe current ISO 8601 week number is shown below; pick any date to see which week it falls in.
- World ClockBuild a list of cities and watch their current times tick live, with UTC offsets and day differences against your local time.
About these time & date tools
Date arithmetic is deceptively awkward: months vary in length, leap years break naive formulas, and time zones shift the answer depending on where the question is asked from. The tools here follow calendar rules rather than approximations, which is why their results match what forms and institutions expect.
Alongside the calculators sit the practical ones — timers, countdowns, a pomodoro clock. Those run entirely on your device, so they keep counting whether or not the connection does.