Subtract Days Calculator

Subtract days, weeks, months or years from a date to find an earlier date.

What is the Subtract Days Calculator?

Useful for finding dates in the past — when a 45-day period started, or the date 6 months before a deadline.

How does it work?

The calculator moves backwards by the chosen amount, handling month lengths and leap years.

Formula

Result = Start − N days

Example

45 days before 1 December 2026 is 17 October 2026.

Frequently asked questions

Are leap years handled?

Yes. All calculations use the real calendar, including 29 February in leap years.

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