Count days, find a date in the future, work out an exact age or the hours worked in a day. Weekdays and weekends are counted for you.
- Age Calculator: Exact Age in Years, Months and Days
- Days Between Two Dates Calculator
- Add or Subtract Days From a Date
- Hours Between Two Times Calculator
- What Day of the Week Was It? Day of Week Calculator
- Add or Subtract Time (Hours and Minutes)
- Hours and Minutes to Decimal Hours
- Length of Service Calculator
- Paid Leave Calculator (France)
- Business Days Calculator (Add Working Days)
- Time Zone Converter
- Time Calculator (Add, Subtract, Multiply Durations)
- Timesheet Calculator (Hours Worked)
- Military Time Converter (24-Hour Clock)
- Sunrise and Sunset Calculator
- Hours to Days Converter
- What Week Is It? Week Number Today
- French Public Holidays by Year
- How Many Days Until Christmas? Countdown
- How Many Days Until New Year? Countdown
- How Many Days Until Easter? Countdown
- How Many Days Until Valentine’s Day?
- How Many Days Until Halloween?
- How Many Days Until Summer?
About these calculators
Counting days by hand is error-prone because months have different lengths and leap years add a day. These calculators find the time between two dates, add or subtract days, compute an exact age, count working days and convert time zones and durations.
Every tool is free, works on phone and computer, needs no sign-up and runs in your browser: what you type is not sent to a server. Each page explains the formula, gives a worked example and answers common questions.
Some tools in this category: Age Calculator: Exact Age in Years, Months and Days, Days Between Two Dates Calculator, Add or Subtract Days From a Date, Hours Between Two Times Calculator, What Day of the Week Was It? Day of Week Calculator.
Tips for accurate results
- Decide whether the end date counts: many tools exclude it by default.
- Working days depend on public holidays, which differ by country.
- Check time zones and daylight saving time for international dates.