Count the days between two dates
From project deadlines and lease terms to counting down to a holiday, knowing the exact number of days between two dates is a surprisingly common need — and a surprisingly easy one to get wrong by hand once months and leap years are involved. This calculator does it precisely.
How to use the calculator
Enter a start date and an end date. The order does not matter — the result is always given as a positive number. Alongside the exact day count you also get the equivalent in weeks and approximate months.
Exact days versus approximate weeks and months
Days are the precise unit here. Weeks are exact too (one week is always seven days), but months are shown as an approximation using the average month length of about 30.44 days, because calendar months vary from 28 to 31 days. For anything that must be exact to the day — a contract, a notice period, a countdown — rely on the day figure.
Inclusive versus exclusive counting
One thing to watch when the count matters legally or financially is whether both the start and end days should be included. "From the 1st to the 8th" could mean seven days or eight depending on the convention. This calculator counts the gap between the dates; if your contract counts both endpoints, add one. When in doubt, check the exact wording of the agreement you are working to.