Time And Date calculators

Time and date calculators for duration, age, countdowns, and scheduling. Handles leap years, time zones, and daylight saving correctly.

12 calculators

  • Absence Percentage Calculator

    Work out an employee, team, or organisation absence rate as a percentage of scheduled working days. Uses the standard CIPD / SHRM absence-rate formula.

  • Age Calculator

    Work out exact age in years, months, and days between a date of birth and any reference date. Also shows total days lived, day of the week born, and the next birthday.

  • Age Difference Calculator

    Enter two dates of birth and get the exact age gap in years, months, and days — plus the total days, weeks, and months between them.

  • Age in Weeks Calculator

    Work out how many weeks old you are. Enter a date of birth and a reference date to see total weeks lived, the day remainder, total days, and the day of the week you were born.

  • Age on Other Planets Calculator

    Enter your Earth age and see how old you would be on every other planet in the Solar System — in local planet-years and in local sidereal days (sols).

  • Countdown Calculator

    Count the days, weeks, hours, minutes, and seconds remaining until any target date — or how long it has been if the date is already past.

  • Date Calculator

    Add or subtract days, months, and years from any date. Returns the resulting date in long form and ISO 8601, the day of the week, and the total day shift.

  • Day Counter

    Count the exact number of days between two dates — and see the same span as years/months/days and as weeks. Works for past, future, or mixed.

  • Days Until Thanksgiving Calculator

    Count down to the fourth Thursday of November — the exact days, weeks, hours, minutes, and seconds remaining until Thanksgiving Day, plus the calendar date it falls on.

  • Days Until Valentine's Day Calculator

    Count down to 14 February — the days, weeks, hours, minutes, and seconds remaining until Valentine's Day, plus the day of the week it falls on.

  • Time Duration Calculator

    Find the elapsed time between two times of day. Returns hours and minutes, decimal hours, total minutes, and flags whether the duration crosses midnight.

  • Workday Calculator

    Count the number of working days — Monday to Friday — between any two dates. Optionally exclude a number of public holidays. Useful for project deadlines, contract terms, payroll periods, and statutory time limits.