Date & Time Calculators

How many days between two dates — with the weeks, months, and working-day counts alongside.

The exact gap between two birthdays, in years, months, and days — and who is older.

Monday-to-Friday days between two dates, with the weekend and calendar totals to check it against.

Days from today to any date, broken into weeks, months and Monday-to-Friday business days.

Add or subtract years, months, weeks and days, in calendar days or business days only.

What weekday any date fell on, plus its day of year, ISO week, quarter and leap-year status.

Hours and minutes between two clock times, less an unpaid break, in decimal hours for payroll.

The ISO 8601 week number for any date, including the years where 1 January belongs to week 53.

Whether a year is a leap year, which rule decided it, and the nearest leap years either side.

A time in one city read in another, with the clock changes either side and the hours that do not exist.