Subtract Days from Date
Enter a date and an amount to find the earlier date: 30 days ago, 6 weeks before a deadline, or 10 business days back.
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What is Subtract Days from Date?
Counting backwards is a common chore: the date a warranty started, the last day to give notice, the day an invoice was issued when you only know the due date and the payment term. This tool subtracts an amount of days, weeks, months or years from a start date and tells you the resulting date and its weekday.
With "skip weekends" it counts back over Monday-to-Friday business days only, so 10 business days before Friday 25 September 2026 is Friday 11 September, not the 15th. Month and year subtraction uses end-of-month clamping: 31 March minus 1 month is 28 February (29 in a leap year). Paste several dates, one per line, to subtract the same amount from all of them, and read the results as a table.
How does it work?
- Type or paste the start date(s), one per line, or write today.
- Enter the amount to subtract and choose days, weeks, months or years.
- Tick "skip weekends" to count only business days (days and weeks).
- Read the earlier date and its weekday, or the table for several dates, and copy the result.
Common use cases
- Finding the day a contract or warranty started from its end date and duration.
- Working out the last day to send a notice that must reach the other party 30 days before an event.
- Counting back 5 or 10 business days from a delivery date to plan production.
- Checking what the date was 90 days or 6 months ago for a report or audit.
Examples
Try this input in the tool above:
2026-09-25 2026-03-31
2026-09-11 2026-03-17
Privacy
Subtract Days from Date runs entirely in your browser. The text or files you provide are processed on your device and are not uploaded, logged or stored on our servers.
Limitations
Business days mean Monday to Friday only: public holidays and regional working weeks are not taken into account, and the weekend option is not available for months and years.
Frequently asked questions
What is 31 March minus one month?
February has no 31st, so the day is clamped to the end of the shorter month: 28 February, or 29 in a leap year. The tool shows a note whenever it had to adjust a day this way.
How are business days counted backwards?
Each step goes one calendar day back and only Monday to Friday count. Starting on a Saturday, 1 business day back is Friday. A week counts as 5 business days when weekends are skipped.
How is this different from the Add Days tool?
It always subtracts, so there is no operation switch to forget, and it is set up for looking back in time: the output is labelled as the earlier date and the defaults suit "N days ago" questions.
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