Date & Time calculators
Ages, durations, deadlines and countdowns
- Add or Subtract Days Calculator Days before or after any date
- Age Calculator Exact age in years, months and days
- Business Days Calculator Count weekdays between two dates
- Countdown Calculator Days until any future date
- Date Difference Calculator Days, weeks and months between two dates
- Time Duration Calculator Hours and minutes between two times
- Work Hours Calculator Paid hours per shift and per week
Which date calculator to use
To count the days between two dates, use the date difference calculator; to count only weekdays, use the business days calculator. To find the date a set number of days before or after another, use the add or subtract days calculator, and to see how long is left until a date, the countdown calculator. The age calculator gives an exact age in years, months and days from a date of birth, along with the days until the next birthday.
For clock time rather than calendar dates, the time duration calculator finds the hours and minutes between two times, and the work hours calculator turns clock-in and clock-out times into paid hours per shift and per week after the unpaid break, including shifts that run past midnight.
Calendar arithmetic has traps that are easy to fall into by hand: leap years, months of different lengths, and the hour that daylight saving time adds or removes. The date calculators count whole calendar days, so a daylight saving change never moves a result by a day, and each page explains the counting rule it follows with a worked example.