Enter how many days to count backward from a start date — defaulting to today — to see the resulting past date.

How it works

This calculator subtracts whole calendar days from a start date. It is the inverse of adding days: 10 days ago from 5 March is 24 February, including the month boundary. Arithmetic uses the calendar (year, month, day), not clock timestamps, so a daylight saving change never moves the result by a day.

Formula

Result date = Start date − Number of days

Worked examples

  • 2024-03-05 − 10 days February 24, 2024
  • 2024-03-01 − 1 day February 29, 2024

Useful notes

  • The start date defaults to today in your browser; change it to count back from any other day.
  • Leap years are included automatically — February has 29 days when it should.

FAQ

What date was it 30 days ago?
Leave the start date as today and enter 30. The result is the calendar date 30 days before that start date, including the weekday.
Does this skip weekends?
No. It counts every calendar day. Use the business days calculator if you only want weekdays.
Will the result jump because of my time zone?
No. The calculation uses calendar dates only, so evening in one zone does not roll the answer into a different day.

Related tools

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