Days Between Two Dates Calculator

Days between two dates calculator — count exact days, weeks and months between any two dates. Use the free Days Between Two Dates Calculator below — enter your values and get instant results, right in your browser. Logic: both dates are read as UTC midnight and subtracted; the difference in milliseconds is divided by 86,400,000 (ms per day). Weeks = days ÷ 7; the Y/M/D breakdown uses calendar month lengths, including leap years.

How to use the Days Between Two Dates Calculator

Planning a trip, tracking a pregnancy, counting down to an exam or checking a notice period all come down to one question: how many days are between these two dates? Counting on a calendar is slow and easy to get wrong. This days between two dates calculator gives you the exact answer instantly — total days, equivalent weeks, and a full years-months-days breakdown — with no signup and no app to install.

  1. Open the Difference tab of the calculator.
  2. Enter the earlier date in the first date field.
  3. Enter the later date in the second date field.
  4. Click Calculate to get the result instantly.
  5. Read the total days, the weeks equivalent and the years/months/days breakdown.

Formula

Logic: both dates are read as UTC midnight and subtracted; the difference in milliseconds is divided by 86,400,000 (ms per day). Weeks = days ÷ 7; the Y/M/D breakdown uses calendar month lengths, including leap years.

Worked example

From 1 January 2026 to 12 October 2026. Click Calculate. Result: 284 days, which is 40 weeks and 4 days, or 9 months and 11 days. Perfect for checking exactly how far away a deadline is — adjust either date and the breakdown updates instantly.

Frequently asked questions

It counts the number of days between the two dates, i.e. end minus start. Add 1 if you need both endpoints counted.

Swap them so the earlier date comes first for a positive count of days between them.

Yes, real calendar arithmetic is used, so February 29 is counted whenever it falls in the range.