Calculators
Date Math & Workdays Calculator
Add or subtract dates, measure a duration, and count working days with optional holidays.
Dates and holiday lists are calculated locally in your browser. Nothing is uploaded.
Date calculator
Add or subtract days, measure a duration, or count working days with an optional holiday list.
Use YYYY-MM-DD, one per line or comma separated. Holidays only affect working-day mode.
How dates are calculated
Date math runs in UTC so daylight saving changes cannot add or remove a day. Month and year additions clamp to the last valid day, so 31 January plus one month becomes the last day of February. Working days are counted inclusively from the start date through the end date.
Holiday dates are not fetched from an external calendar. Paste the dates you want to exclude.