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Date Difference Calculator

Find the exact number of days between two dates, plus the equivalent in weeks, months, and years.

Date Difference Calculator

Live
Days between
Enter both dates
Weeks
-
Months (approx.)
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Counts full calendar days between the two dates.

The formula

Days between = End date - Start date (in full calendar days)
Example

January 1, 2026 to July 19, 2026: 199 days, or about 28.43 weeks, or about 6.54 months.

Step-by-step guide

  1. Enter the start date and end date.
  2. Read the exact day count, plus the equivalent in weeks and approximate months.

Common mistakes

Assuming every month is exactly 30 days when estimating by hand - actual month lengths vary from 28 to 31 days.
Not deciding whether to count the start date itself - this calculator counts the difference between the two dates, not an inclusive day count.

Frequently asked questions

Does this count the start date as day 1?

No - this shows the number of days between the two dates (end minus start). If you need an inclusive count (counting both the start and end date), add 1 to the result.

Can I use this for a date in the past and get a negative number?

Yes - if the end date is earlier than the start date, the result will be negative, showing how many days before the start date it falls.

Why is the "months" figure approximate?

Months vary in length (28-31 days), so converting a day count to months uses an average month length (30.44 days) rather than an exact calendar count.

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