Date Difference Calculator
How long between two dates: the exact number of days, and the same gap in weeks, months and years.
Two dates, and every way of saying how far apart they are. The plain day count is the one that never surprises anyone; the others are the ones people actually use in a sentence.
How it works
The day count is the number of days from one date to the other, counting the gap rather than the dates themselves: 1 January to 2 January is one day. Leap years are included, so a span containing 29 February is a day longer than the same span elsewhere.
The years, months and days breakdown walks the calendar rather than dividing. Months are not all the same length, so "one month and three days" cannot be recovered from a day count alone.
Examples
| Case | Input | Result |
|---|---|---|
| A whole year | 2024-01-01 to 2024-12-31 | 365 days |
| Leap day to leap day | 2000-02-29 to 2024-02-29 | 8,766 days, exactly 24 years |
Frequently asked questions
Are both dates counted?
The difference is the gap between them, so no. Counting both ends — as you would for the number of days of a stay — gives one more. The working days calculator does count both ends, because that is what a working period means.
Does the order matter?
Not for the size of the gap, which is always reported as a positive span. Which date comes first is reported separately.
Good to know
- The years, months and days breakdown is not symmetric, because months are not the same length. From 31 January to 1 March 2026 is 29 days, written as no months and 29 days; the other way round the same 29 days are written as one month and one day.
- The day count is a count of calendar days rather than of elapsed hours, so a day on which the clocks change still counts as one.