Date & Time calculators
Ages, durations, and countdowns.
- Age Calculator: Exact Age in Years, Months and Days
Exact age in years, months and days on any date, with total months, weeks and days and the next birthday.
- Date Difference Calculator: Days, Weeks, Months Between Dates
Years, months and days between two dates, plus total days, weeks and months, counted both ways.
- Add or Subtract Days, Weeks, Months or Business Days From a Date
A date plus or minus days, weeks, months, years or business days, skipping US federal holidays if you like.
- Countdown Calculator: Days Until a Date
Days, weeks and hours until a target date, counted from today or any other day.
- Business Days Calculator: Workdays Between Dates, US Holidays
Weekdays between two dates, inclusive, with the option to skip US federal holidays as observed.
- Duration Calculator: Hours, Minutes, Seconds to Decimal Hours
Turn any hours, minutes and seconds into a tidy duration, decimal hours, minutes and seconds.
- Week Number Calculator: ISO and US Week of the Year
The ISO 8601 week number and the US (Sunday-start) week number for any date, with the week's dates.
- Time Zone Converter: Convert Time Between UTC Offsets
Convert a clock time from one UTC offset to another, including half-hour zones, with the day change shown.
- Bedtime Calculator: When to Go to Sleep for Your Alarm
Bedtimes that fit whole 90-minute sleep cycles before your alarm, plus 15 minutes to fall asleep.
- Hours Calculator (Time Duration Between Two Times)
Hours and minutes between a start and an end time.
- Time Card Calculator (Time Clock Hours & Overtime)
Weekly hours, overtime and gross pay from clock times.