Date Difference Calculator

Count the days, weeks & months between two dates.

Find the exact duration between two dates — in days, weeks, months and a full years / months / days breakdown. Pick a start and end date, optionally count the end day too, and see the weekday vs weekend split for working-day counts. Perfect for notice periods, project timelines, leave, deadlines and ‘how many days until…’. Runs fully in your browser — nothing is uploaded.

How to use Date Difference Calculator

  1. Pick start date

    Open the free online Date Difference Calculator and choose your start date using the native calendar picker for fast, accurate selection on any device.

  2. Choose end date

    Select the end date to instantly calculate the exact number of days between the two dates, with no manual counting or spreadsheet formulas required.

  3. Include end day

    Tick the include the end day option when you need both endpoints counted, ideal for leave, event days or any inclusive date-range duration.

  4. Read the duration

    View the total days plus a clear years, months and days breakdown, so you instantly understand how long the span between your two dates really is.

  5. Check working days

    See weekdays and weekend days split out alongside total weeks, months and hours, perfect for notice periods, project timelines and working-day counts.

  6. Reset or share

    Hit reset to start a fresh date calculation or share your result link instantly, since everything is computed privately in your browser, never uploaded.

Frequently asked questions

Does it count both the start and end day?

By default it counts the gap between the two dates (the start day is day 0). Tick “include the end day” to count both endpoints — for example, a 1st-to-5th leave that should total 5 days.

How are weekdays and weekend days counted?

The calculator walks the span and tallies Monday–Friday as weekdays and Saturday–Sunday as weekend days. It does not account for public holidays, which vary by region.

What if I enter the end date before the start date?

No problem — it still gives the correct duration and just notes that the dates were in reverse order.

How do I calculate the number of days between two dates?

Pick a start date and an end date and this date difference calculator instantly shows the days between them, plus a weeks, months and years/months/days breakdown. Tick “include the end day” if you need both dates counted.

How many days until a future date or since a past date?

Set today as one date and your target date as the other — the calculator works out exactly how many days until an event or how many days have passed since one, making it ideal for deadlines, anniversaries and countdowns.

Does the date difference calculator count only working days?

It splits the span into weekdays (Monday–Friday) and weekend days (Saturday–Sunday) so you can read off the working-day count, but it does not subtract public holidays, which vary by region.

Is my data sent anywhere?

No. Everything is calculated in your browser with JavaScript — nothing you enter is uploaded.

How do I calculate how many days until my birthday or an event?

Enter today's date as the start and your birthday or event date as the end — the calculator instantly shows how many days remain, plus a weeks and months breakdown. It's perfect for counting down to birthdays, weddings, exams and holidays.

Can it count the number of weeks or months between two dates?

Yes. Alongside the day count, it shows the span in weeks, in months, and as a full years / months / days breakdown, so you can read the same duration in whichever unit suits notice periods, project timelines or anniversaries.

Is the date difference calculator free to use?

Yes — it's completely free with no sign-up, and every calculation runs in your browser, so nothing you enter is uploaded. Work out as many date gaps as you like on any phone, tablet or computer.

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