Add or subtract days
Add days to a date, or count back from one. Choose calendar days or working days, and the tool shows the resulting date and its weekday.
How this calculator works
Enter a start date and a number of days, then choose whether to add or subtract. The tool returns the resulting date and the day of the week it falls on. Switch the day type to working days and it counts Monday to Friday only.
Worked example. Ninety days after 10 July 2026 is 8 October 2026, a Thursday. The same 90 counted as working days lands in mid November, because weekends are skipped.
Common uses
- Payment terms: 30 or 60 days from an invoice date.
- Notice periods and deadlines: count back from a due date.
- Delivery and returns windows quoted in working days.
Common questions
What is the difference between calendar days and working days?
Calendar days count every day. Working days count Monday to Friday only, so adding five working days to a Friday lands on the next Friday.
Can I count backwards?
Yes. Choose subtract to find a date a number of days before your start date, which is handy for deadlines and notice periods.