Subtract Days, Months, or Years from a Date Online — Free
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.
About this tool
Subtracting time from a date
Enter a date and take away days, weeks, months, or years — the tool lands on the exact result, calendar-aware through month lengths and leap years. Subtracting a month from March 31 correctly reaches the last day of February rather than skipping into nonsense.
The backward-looking questions
When did this subscription start, given it renews monthly? What date fell exactly 90 days before the deadline? When was the file created, given it is 45 days old? Subtraction answers the history questions that addition answers for the future.
Subtraction versus difference
Subtracting moves from a known date to an unknown one; the date difference tool measures between two known dates. They are two halves of the same arithmetic — use whichever direction your question points.
Frequently asked questions
What happens when subtracting a month from March 31?
The result lands on the last day of February — calendar-month arithmetic clamps to the real month length instead of rolling into the next month.
Can I subtract years and months together?
Run two passes: subtract the years first, then the months, then days if needed. Calendar-aware arithmetic applies at each step.
Does the result handle leap years?
Yes — February 29 exists in the result when the target year supports it, and clamps to the 28th when it does not.