Add or Subtract Time From a Date
Add or subtract any combination of years, months, weeks, days, hours, minutes, or seconds from a date. Chain multiple adjustments.
Runs 100% in your browser — nothing is uploaded.
Operation
Adjustments
Result
Fri Sep 11 2026 03:19:00 GMT+0000 (Coordinated Universal Time)
ISO:
2026-09-11T03:19:00.000ZDelta: 30d
Frequently asked
How does "add months" handle month lengths?
It uses JavaScript's native Date.setMonth() semantics. Adding 1 month to Jan 31 lands on Mar 3 (Feb 28 + 3). Adding 1 month to Jan 15 lands on Feb 15.
What is the "delta" line?
A human-readable difference between the start date and result: "5d 3h 12m". Useful for double-checking your adjustment.
Can I mix add and subtract?
Not in one operation — the mode applies to all adjustments. But you can add days then run again with subtract to fine-tune.
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