Pick a start date and add or subtract days, weeks, months, or years to find the resulting date.
Adding and subtracting time
Working out a date a certain time away from another sounds trivial until months and leap years get involved. This calculator shifts a start date forward or backward by days, weeks, months, or years, respecting the real calendar so month lengths and leap days are handled for you.
It is the everyday tool for deadlines, contract renewals, warranty expiries, and planning ahead. Because it follows calendar rules rather than a flat day count, adding one month to January 31 behaves the way you expect.
The formula
Worked example
30 days after a date in June lands in late July.
How to read your result
Adding months or years respects the calendar, so month lengths and leap years are handled automatically. Use it for deadlines, renewals, and planning ahead.
Frequently asked questions
- Does it handle months correctly?
- Yes, it shifts by calendar months, not a fixed number of days.
- Can I subtract?
- Yes, choose subtract to count backward from the date.
- What about leap years?
- They are handled automatically using real calendar dates.
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