Date and Time

Exact age in years, months and days, and a browser stopwatch.

Date and time tools help you measure exact age in years, months and days, and time an activity with a browser stopwatch. Age is calculated from calendar dates, so the time of day does not change the result.

• Age Calculator

  Calculate exact age in years, months, days and total days from a date of birth.

• Online Stopwatch

  Start, stop and reset a stopwatch with centisecond precision in your browser.

How to use the date and time tools

The age calculator needs only a date of birth. It shows your age in years, months and days, and the total number of days you have lived. The stopwatch starts, stops and resets with three buttons.

Dates are read as calendar dates in the Gregorian calendar, so the result does not change with your time zone or the time of day.

Common uses

People use the age calculator to check eligibility for a course or a form, to plan a celebration, or to confirm the age on an application. Coaches and trainers use the stopwatch to time short activities. For official sport timing, use certified equipment.

Accuracy notes

The age calculator counts whole days and does not handle every local legal rule for birthdays, especially for people born on 29 February. The stopwatch reads the device clock, so very short timings may vary a little between devices.

Questions