Date Duration Calculator
betaThis free date calculator does two things: it finds the duration between two dates (as years/months/days, total days and working days), and it adds or subtracts a number of days from a date to find the resulting date. Everything is worked out in your browser.
Find the time between two dates — in years/months/days, total days, and working days — or add/subtract days from a date. All in your browser.
Difference between dates
Add or subtract days
How to use Date Duration Calculator
- 1 Pick a From and To date to see the duration between them.
- 2 Read the breakdown: years/months/days, total days, and working days (Mon–Fri).
- 3 To project a date, enter a start date and a number of days (use a minus sign to go back).
- 4 The resulting date appears instantly.
Frequently asked questions
Is anything sent to a server?
No. All the date math runs in your browser — nothing is uploaded.
Are both dates counted?
The total-days figure is the number of days from the first date to the second. Working days count each Monday–Friday in the range, inclusive of both endpoints.
Can I count backwards?
Yes. For "add or subtract days", enter a negative number to find a date in the past.
How are months counted?
The years/months/days breakdown uses calendar months, borrowing the length of the previous month when the end day is earlier than the start day.