Date Difference Calculator
Enter a start date and an end date to see the precise difference between them, broken down into years, months, days, total weeks, and total days. The calculation uses calendar-accurate date math, correctly handling varying month lengths and leap years.
Useful for project planning, contract durations, age verification, or any situation where you need to know exactly how much time separates two dates. The result updates instantly as you change either date.
Everything runs in your browser — no data is sent to a server.
By The Paper Room Editorial Team — Date Tools
Frequently asked questions
How is the months/days breakdown calculated?▼
It subtracts the year, month, and day components of the two dates, borrowing from the month count when the end day is earlier in the month than the start day. The number of days borrowed matches the actual length of the preceding month, so it handles February, leap years, and 30- vs 31-day months correctly.
Does it account for leap years?▼
Yes. The total days count is computed from the exact difference between the two calendar dates, which includes every leap day that falls in the range.
Can I use future dates?▼
Yes. You can enter any two dates — past, present, or future — and the tool will calculate the difference between them.