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Days Between Dates Calculator

Find out how many days, weeks, months and business days there are between two dates.

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Difference

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Days
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Weeks
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Business days (Mon–Fri)
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Hours
Runs in your browser – your data never leaves your device Also available via our free API

How to use the Days Between Dates

  1. 1 Choose a start date and an end date.
  2. 2 Tick “Include the end date” if the last day should count as well.
  3. 3 Read the difference in years, months and days, plus total days, weeks, business days and hours.

Counting days correctly

By default the calculator counts the days between two dates: from 1 January to 31 December 2026 is 364 days. If both the first and the last day should count – for a holiday, a rental period or a project – tick Include the end date and the result becomes 365 days.

If the end date is before the start date, the calculator swaps them and shows the result with a minus sign.

Business days

Business days count Monday to Friday only. Public holidays differ by country and region, so they are not subtracted automatically – deduct them yourself if needed. In 2026, for example, there are 261 weekdays.

Years, months and days

The difference is also shown as calendar years, months and days. Months are counted from the start date’s day of the month; if that day does not exist in a month, the last day of the month is used. From 31 January to 28 February is therefore exactly one month.

Typical uses

  • Countdown to a holiday, wedding or deadline
  • Notice periods, contract durations and warranty periods
  • Counting working days for invoices or project planning
  • Finding the number of days for interest calculations

Frequently asked questions

How many days are there between two dates?

Enter both dates; the calculator subtracts them using the real calendar, including leap years. Tick “Include the end date” to count both the first and the last day.

Are public holidays excluded from business days?

No. Business days are Monday to Friday. Because holidays differ by country, subtract them manually.

How many weeks are between two dates?

The “Weeks” tile shows the number of full weeks plus the remaining days.

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