Date difference calculator
Enter your numbers — the results update instantly.
Days364
Weeks52
Months11.99
Worked example
Given: Start date = 2026-01-01; End date = 2026-12-31
Result: Days = 364; Weeks = 52; Months = 11.99
How it is calculated
1. Enter the values you know. 2. The calculator converts them to base units and applies the formula. 3. The result is shown in the unit you choose.
Frequently asked questions
How do I calculate it?
Given: Start date = 2026-01-01; End date = 2026-12-31. Result: Days = 364; Weeks = 52; Months = 11.99.
Is the calculator free and private?
Yes. It is free, needs no sign-up and runs in your browser — the numbers you type stay on your device.