Add or subtract
Time calculator
Date Calculator
Add or subtract years, months, weeks, days, and business days from a date. Calculate the duration between two dates in calendar units, total days, hours, minutes, and seconds.
Calculate days between two dates
Choose whether to include the end date in the count. Business days exclude Saturday and Sunday.
Date calculation notes
| Task | How it is calculated |
|---|---|
| Add years/months | Calendar years and months are applied with browser Date rules, then weeks/days are applied. |
| Add business days | Business-day mode moves one day at a time and counts Monday through Friday only. |
| Days between dates | The second date minus the first date at local midnight. |
| Include end date | Adds one day to total day-style results when the second date is not before the first. |
Examples
Adding 30 days to July 6, 2026 gives August 5, 2026, which is a Wednesday. The duration from July 6, 2026 to August 5, 2026 is 30 total days, or 720 hours.
FAQ
Does business-day mode include holidays?
No. It excludes Saturdays and Sundays only. Public holidays vary by country and are not included in this static calculator.
Why can month calculations feel uneven?
Calendar months have different lengths. Adding one month to January 31 may roll into a different day than adding 30 days.
Are times and time zones included?
This page calculates whole dates at local midnight. It is intended for date math, not time-zone conversion.