Date Difference Calculator
Free date difference calculator. Find the time between two dates in years, months and days, plus total days, weeks and hours — and add or subtract days from any date.
Difference between two dates
Total days
Weeks
Months (approx)
Total hours
Add or subtract days from a date
🔒 Dates are processed in your browser — nothing is uploaded.
Free Date Difference Calculator
This free online date difference calculator tells you exactly how much time is between any two dates. Pick a start date and an end date and it shows the gap as a calendar breakdown of years, months and days, plus handy totals in days, weeks, months and hours. There is also a quick add or subtract days tool to find a future or past date. It’s free, instant and runs entirely in your browser, so your dates are never uploaded.
How to use the date difference calculator
- Pick a start date in the first box.
- Pick an end date in the second box.
- Optionally tick Include the end day if you want both the start and end dates counted.
- Click Calculate difference to see the years/months/days breakdown and all the totals.
- To find a future or past date, use the second card: enter a date and a number of days (use a minus sign to subtract), then click Get resulting date.
How the difference is calculated
There are two useful ways to measure the gap between two dates, and this tool gives you both. The calendar breakdown (for example “2 years, 1 month, 5 days”) is how people naturally describe a duration. It is worked out by comparing the day, then the month, then the year, and “borrowing” from the next unit when needed — which is why it correctly accounts for months having different lengths and for leap years. The total days figure is the raw number of calendar days between the dates, and from it we derive weeks (with leftover days), an approximate number of months, and the total hours.
The optional include the end day setting adds one day to the count so that both endpoints are included — useful when you are counting things like the number of days in a booking, an event or a notice period where the last day still counts. Because the calculator uses real calendar maths, February 29 in leap years and the varying lengths of each month are all handled automatically. For example, from 1 January 2024 to 1 March 2024 it returns 60 days, because 2024 is a leap year and February has 29 days.