Subtract Days, Months, or Years from a Date Online
Runs 100% in your browser — your files never leave your device.
Counting backwards is where date math gets fuzzy: thirty days before the 31st, one month back from a month end, a year before a leap day. Enter the starting date and the amounts to subtract, and get the precise result. Month arithmetic clamps to real month ends — March 31 minus one month is February 28, or 29 in leap years.
How it works
- 1
Pick the starting date
Use the date-time picker — the time of day is carried through the math.
- 2
Enter the amounts to subtract
Years, months, days, hours, minutes — all subtracted at once.
- 3
Read the resulting date
The exact date is shown in full, formatted for your locale.
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