Add or Subtract Days Calculator
Add or subtract a number of days from a given date to find a future or past date, shown in Australian DD/MM/YYYY format.
Your results
Calculation breakdown
- Add
- Start date + N days
- Subtract
- Start date − N days
Worked example
Starting 01/06/2026 and adding 90 days gives 30/08/2026, a Sunday.
Assumptions
- Uses plain calendar days — weekends and public holidays are not skipped.
- For business-day arithmetic, use the Business Days calculator instead.
How this calculator works
Choose a starting date, then add or subtract any number of days to instantly see the resulting calendar date. This is useful for working out contract end dates, notice periods, warranty expiries or reminder dates.
Frequently asked questions
Can I subtract days instead of adding?
Yes, choose 'Subtract' from the operation option to move backwards from the start date.
Does this count weekends and holidays?
This calculator uses plain calendar days; use the Business Days calculator if you need to skip weekends and holidays.
What date format is used?
All dates are shown in the Australian DD/MM/YYYY convention.
Editorial review and responsibility
Reviewed by the CalcAussie editorial team on 21 September 2026. Review scope: Method, Australian terminology, material assumptions, source links and user-facing limitations.
Calculator results remain estimates based on the figures entered. Check material decisions against current official information and report a suspected error so it can be reproduced and corrected.