Use this free date difference calculator to find how many days, weeks, months, and years are between two dates.
How to use this date difference calculator
Select a start date and an end date, then press Calculate Difference. The order does not matter; the calculator always measures the period between the two dates.
How the difference is calculated
The calculator counts whole years first, then whole months, then remaining days. It also converts the same period into a total number of days and weeks.
Example
From 1 January 2025 to 1 January 2026 is exactly 1 year, which is 365 days.
Frequently asked questions
Does it count the end date?
The total is the number of full days between the two dates, the standard way date differences are measured.
Can I calculate dates in the past?
Yes. Pick any two dates, past or future.