Add/Subtract Time from Date
Add or subtract days, weeks, months, or years from any date.
What is Add Time?
A calendar-aware date arithmetic tool. Add '3 months' to January 31 and you correctly get April 30, not a rolled-over May date.
How it works
Months and years are applied with clamping to the last valid day of the target month, then days/weeks are added as exact day offsets.
- Enter your input. Type or paste your input into the field above — the tool responds instantly.
- Review the result. Output updates live as you type. Everything runs entirely in your browser.
- Copy or download. Use the Copy button to grab the result, or Download to save it as a file.
Examples
Deadline math
Add 90 days to a contract start date and see the exact end date — no manual calendar counting, leap years included.
Common mistakes
Month-end overflow
Adding one month to January 31 shouldn't yield March 2 or 3. The tool clamps to the last valid day of the target month and tells you when it did.
Frequently asked questions
Can I mix units like months and days?
Yes — add 2 months and 5 days in a single operation. Months are applied first, then days, and the result is clearly broken down.
Does it handle negative (subtract) operations?
Yes, subtract any unit or combination to find dates before a given point.
Is a month always 30 days?
No — months are added as calendar months. If you need fixed-length periods, add days instead (e.g., 90 days rather than 3 months).