Date Calculator
Add or take away days, weeks, months and years — or find exactly how far apart two dates are.
Monday, 5 October 2026 plus 90 days
Sunday, 3 January 2027
How the date calculator works
Adding months keeps the day of the month where it can. When the month is too short it uses the last day: 31 January plus one month is 28 February (29 in a leap year).
Differences are shown as days, as weeks and days, and as calendar months and days.
Examples
- 1 January 2026 + 90 days = 1 April 2026.
- 1 April − 30 days = 2 March.
- 1 January → 1 March 2026 is 59 days: 8 weeks and 3 days, or exactly 2 months.
Good for
- Working out a due date
- Counting down to an event
- Checking an age or an anniversary
Frequently asked questions
- Does it account for leap years?
- Yes — every calculation uses the real calendar, so February has 29 days in 2028.
- How do I count only working days?
- Use the Business Days Calculator, which skips weekends and public holidays.
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Never lose track of a date again
Daykite keeps birthdays, deadlines and plans on one calendar, with reminders.