Count the days between two dates, shown as years, months and days and as total days, weeks and weekdays, or add and subtract days from a date.
How to count days between dates
The calculator subtracts the start date from the end date. By default it does not count the end date itself, which matches how most people count durations ("from Monday to Friday is 4 days"). Choose "Include end date" if you need to count both days, for example for a hotel stay or event that runs through the final day.
Worked example
From January 1, 2026 to December 25, 2026 there are 358 days: 11 months and 24 days, or 51 weeks and 1 day.
Adding 90 days to January 1, 2026 gives April 1, 2026.
Common uses
- Counting down to a holiday, wedding or trip.
- Working out notice periods, warranty periods or return windows.
- Tracking how long a project, pregnancy milestone or habit streak has lasted.
For deadlines that exclude weekends and holidays, use the business days calculator.
Frequently asked questions
Does it account for leap years?
Yes. It uses the real calendar, so February 29 is counted in leap years.
Why are months shown as approximate?
Months have different lengths, so converting days to months uses an average of 30.44 days. The years-months-days figure is exact.
Related tools
Results are estimates for planning and education only. They are not financial, tax, legal or medical advice. Check important numbers with a qualified professional.