Date Difference
Calculate the time between two dates
Free Date Difference Calculator
Find the difference between two dates in years, months and days
Knowing how many days lie between two dates comes up constantly: planning a project deadline, checking visa or passport validity, tracking an invoice due date, or simply asking "how long have we known each other?". This tool shows the difference between two dates simultaneously as years-months-days and as total days, weeks, months and hours; enable the extra statistics and you'll also get the business-day count that skips weekends. Leap years and unequal month lengths are handled automatically, and the order you enter the dates in doesn't matter. The reference section below covers the calculation rules and the most common scenarios.
Features
Years-Months-Days
Shows the exact difference in full years, months and days, no rounding.
Total Units
See the same span as total days, weeks, months and hours.
Business Days
Counts the weekdays (Mon-Fri) between the two dates.
100% Private
All calculations run in your browser; nothing is uploaded.
Date Difference Guide
How it's calculated
- The difference counts real calendar days
- Leap years (Feb 29) are included automatically
- The years-months-days view follows calendar months
- Business days exclude weekends (Sat-Sun)
- The start day isn't counted: Jan 1 → Jan 2 = 1 day
Common scenarios
- Project/delivery time: today → deadline
- Visa and passport validity checks
- Invoice, debt and contract due dates
- Baby age and relationship anniversaries
- Historical distance between two events
Frequently Asked Questions
How is the number of days between two dates calculated?
By counting real calendar days: the start day is excluded, the end day included. For example, Jan 1 → Jan 31 is 30 days. The tool does this automatically — no adding up month lengths by hand.
Is the start day included?
Not in the standard method: Jan 1 to Jan 2 is a difference of 1 day. If you want both days counted (days of a stay rather than nights, say), simply add 1 to the result.
What do business days exclude?
The business-day figure in the extra statistics skips Saturdays and Sundays. Public holidays vary by country, so they are not subtracted — for strict legal deadlines, also check the holiday calendar of the year involved.
Do leap years affect the result?
Yes, and they're handled automatically. Ranges containing February 29 are one day longer, which is why the same two months can give different day counts in different years.
Why do years-months-days and total days look 'different'?
They're two views of the same difference. Years-months-days follows calendar months (28-31 days each), while total days is a flat count. 1 year 2 months can be 425 or 427 days — both are correct.
Can I count down to a future date?
Yes — set today as the start and the target date as the end. You'll instantly see how many days remain until an exam, holiday, wedding or visa appointment; if you enter the dates in reverse, the tool fixes the direction itself.