Days between two dates
Add or subtract from a date
How adding months works
Adding 1 month to 31 January lands on a month without a 31st, so the result is the last day of February. Years and months are added first, then days.
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Frequently asked questions
Is the first day counted?
Normally no; 1st to 2nd is 1 day. Tick "Include the end date" to count both ends.
How many days are in a year?
A normal year has 365 days and a leap year has 366 days.
Is this tool free?
Yes. It is free to use, with no sign-up or login.
Does it work on my phone?
Yes. The page works on phone, tablet and computer browsers.
Can I add or subtract days, months and years?
Yes. Choose Add or Subtract, enter days, months or years, and the new date is shown.
What happens when I add a month to the 31st?
If the next month has no 31st, the result moves to that month's last day. For example, 31 January plus 1 month gives the end of February.
Does it handle leap years?
Yes. 29 February is counted in leap years, so day counts stay correct across years.