Date Difference
Calculator
Find exactly how many days, weeks, months and years between any two dates — instantly and for free.
All 13 date tools
Everything you need for date maths — all free, all in one place.
Frequently asked questions
How do I calculate the number of days between two dates?
Enter your start and end dates above and click Calculate. The tool instantly shows the total in days, weeks, months and years. Tick the boxes to exclude weekends or UK bank holidays to get working days only.
Can I calculate working days between two dates?
Yes — tick "Exclude weekends" to count only Monday to Friday. Tick "Exclude UK bank holidays" too to remove all public holidays. Or use the dedicated Working Days Calculator.
Does the calculator include or exclude the start and end dates?
The calculator counts from the start date up to but not including the end date — the standard convention. To include both dates, add 1 to the result.
Can I calculate dates in the past and in the future?
Yes — the date fields accept any date from the distant past to far in the future. The result shows the total difference regardless of direction.
How accurate are the results?
Very accurate. The calculator uses JavaScript's native Date engine which correctly handles leap years, varying month lengths, and daylight saving time. Bank holiday data is fetched live from the official UK Government API.
Is DateCalc4Me free to use?
Completely free, forever. No sign-up, no subscription. DateCalc4Me is supported by advertising from Google AdSense.
Why calculate the difference between dates?
People need date calculations for countless everyday reasons:
- Project deadlines — how many days until a deliverable is due
- Pregnancy — counting weeks since conception or a due date
- Legal notices — calculating statutory notice periods precisely
- Age milestones — how many days old you are, or will be
- Finance — interest accrual periods and invoice payment terms
- Travel — how long until a departure date
- Anniversaries — exact days since a wedding or special event
How date difference is calculated
The tool subtracts the earlier date from the later date to get a raw number of days. From there:
- Weeks are total days ÷ 7, rounded down
- Months count full calendar months elapsed
- Years count full 365/366-day years elapsed
When excluding weekends, all Saturdays and Sundays are removed. When excluding bank holidays, an up-to-date list of UK public holidays is used, fetched live from the government's official API.