How to find a date in the past
To find what date it was a certain number of days ago, subtract those days from today. The calculator counts back across months and years automatically, so "90 days ago" or "180 days ago" lands on the correct calendar date.
Doing it by hand means borrowing from each month in turn. To go back 90 days from 20 July 2026: take off 20 days to reach 30 June, another 30 to reach 31 May, another 31 to reach 30 April, and the last 9 days give 21 April 2026. The calculator does the same borrowing instantly and handles 29 February in leap years, so ranges that cross a leap day stay correct.
Useful shortcuts: 7 days ago is the same weekday last week, 14 and 28 days ago are also the same weekday, and 365 days ago is the same date last year unless a 29 February sits in between.
Keep the date plus days calculator nearby for the rest of the same job.
How to use this calculator
Enter the number of days ago and read the resulting date. To go forward instead, use the days from today calculator.
Typical reasons to count backwards include working out when a 30-day return window opened, checking whether a document still falls inside a 90-day validity period, finding the start of a 180-day reference window, or dating the beginning of a reporting period. Round numbers such as 30, 60, 90 and 180 days are the ones that appear in most policies, so they are worth checking exactly rather than estimating in months.
Note that this counts calendar days, weekends and public holidays included. If your deadline is stated in working days, cross-check the range with the days between dates calculator.
Frequently asked questions
- What date was 90 days ago?
- It's today's date minus 90 days — about three months back. The calculator shows the exact day.
- How do I calculate a date in the past?
- Subtract the number of days from today's date, carrying back across months and years.
- Does it count calendar days or business days?
- Calendar days, including weekends and holidays.
- Is today counted?
- No — it counts back starting from today, so '1 day ago' is yesterday.
- Why doesn't 90 days ago land on the same date three months back?
- Because months are 28 to 31 days long, so 90 days is slightly less than three calendar months for most of the year. Counting back 90 days from 20 July 2026 gives 21 April 2026, and the offset shifts depending on which months you cross.