Date Calculator (Add or Subtract)
Add or subtract years, months, weeks, and days from a date to find a new date and its day of the week.
Independently verified for accuracy
Calculator by Toolsloft ↗- Result date
- 2026-08-07
- Day of week
- Friday
Add or subtract years, months, weeks, and days from any date and see the resulting date and its weekday. Use it to find a due date, a deadline, a renewal date, or a milestone a set time before or after a known date. The calculation handles month lengths and leap years for you.
How this is calculated
Years and months are applied on the calendar first. When the target month is shorter, the day is clamped to the last day of that month, so January 31 plus one month becomes the end of February. Weeks are converted to days and applied last as exact calendar days.
How to use
- Enter the starting date.
- Choose whether to add or subtract.
- Enter the number of years, months, weeks, and days, then read the resulting date.
Examples
- Add time:
2026-07-08 plus 1 year 2 months 10 days → 2027-09-18 - Month clamp:
2020-01-31 plus 1 month → 2020-02-29
FAQ
- What happens when the new month is shorter?
- The day is clamped to the last day of that month. Adding one month to January 31 lands on February 28, or February 29 in a leap year.
- In what order are the parts applied?
- Years and months are applied first on the calendar, then weeks and days are added as exact days. This matches how most date math is expected to work.
- Can I go backwards in time?
- Yes. Choose subtract to move the date earlier by the amounts you enter.