Add or subtract
Time calculator
Date Calculator
Add or subtract years, months, weeks, days and business days. Calculate duration between two dates in calendar units and total time.
date +/- duration
Calculate days between two dates
Choose whether to include the end date. Business days exclude Saturday and Sunday.
Date calculation notes
| Task | How it is calculated |
|---|---|
| Add years/months | Calendar years and months are applied first, then weeks and days. |
| Add business days | Moves one day at a time and counts Monday through Friday only. |
| Between dates | Second date minus first date at local midnight. |
| Include end date | Adds the interval start to inclusive day-style results. |
Date calculator FAQ
Does business-day mode include holidays?
No. It excludes Saturdays and Sundays only.
Why can month calculations feel uneven?
Calendar months have different lengths, so one month is not always the same as 30 days.
Are times and time zones included?
No. This calculator works with whole local calendar dates.
What does include end date mean?
It counts both boundaries of the date interval in day-style totals.