Calculate the difference between dates, convert time units, and add or subtract dates — free, instant, and fully in your browser.
Try it Free →Get the exact years, months, and days between two dates plus total days, hours, minutes, and seconds.
Enter a value in any unit and instantly see it in seconds, minutes, hours, days, weeks, months, and years.
Add or subtract any amount of time from a start date and get the target date with its weekday.
Interval math respects leap years and the real length of each month, not just rough averages.
Every result is one tap away — click any value to copy it to your clipboard.
All calculations run locally in your browser. No data is uploaded, no signup required.
Switch between Date Difference, Unit Conversion, and Date Add/Subtract with the tabs at the top.
Choose dates with the native picker or type a number and unit. Use the Now button to fill in the current time.
Results update live as you type — no calculate button needed.
Click any result to copy it, or use the share button to send your calculation as a link.