Date Difference Calculator

Find the exact difference between two dates in years, months, and days, using calendar-accurate arithmetic.

  • Free to use
  • Accurate results
  • No registration required
  • Works on all devices
Enter a start date and an end date to find the exact difference between them in years, months, and days.
Defaults to today's date — change it to any later date.

Your result

6

Years

Months5
Days28
Total days2,372

AI explanation

Formula

Calendar-accurate years/months/days difference with month-end clamping (same engine as the Age Calculator)

Worked example

2020-03-15 to 2026-09-12

Worked example: 2020-03-15 to 2026-09-12
FieldValue
Start date15-03-2020
End date12-09-2026
Years6
Months5
Days28

Assumptions

  • Uses calendar months and the month-end-clamping convention (adding a month to Jan 31 lands on Feb 28 or 29, not an overflow into March) for a consistent, never-negative day count.
  • Dates are treated as calendar dates with no time-of-day or timezone component.

Frequently asked questions

Is this the same as the Age Calculator?

It uses the exact same calendar-accurate calculation, just framed for any two dates (project timelines, anniversaries, tenure) rather than specifically a birth date.

Can I get just the total number of months or years?

Yes — see the Month Calculator or Year Calculator for the same calculation, leading with a single total-months or total-years figure instead of the full breakdown.

Does the order of the two dates matter?

Yes — the end date must be on or after the start date. Swap the two fields if you get a validation error.

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