Add or Subtract Days
Add or subtract days, weeks, months or years from any date.
Pick a start date, an amount, a unit (days, weeks, months or years) and a direction. Get the resulting date plus the difference expressed in days, weeks, months and years.
Common use cases
- Find the date 90 days after a contract signing
- Calculate when a 6-month trial ends
- Plan a 21-day habit challenge end date
- Determine the date 18 years from a child's birthday
Frequently asked questions
How are months handled?▾
Months are added by incrementing the JavaScript month component, so adding one month to Jan 31 gives Mar 3 (the standard "clamp/overflow" behaviour).
Are leap years respected?▾
Yes. Adding one year to Feb 29, 2024 gives Mar 1, 2025 due to month overflow; subtracting one year from Mar 1, 2025 gives Mar 1, 2024.
Does it count business days?▾
No — for that, see the Workday Calculator which lets you skip weekends and holidays.
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