How the days calculator works
Pick a start date and an end date, using the Today buttons if one of them is today. The total appears immediately, together with:
- the same span in weeks and days;
- a calendar breakdown in years, months and days, counted by monthly anniversaries of the start date;
- the number of weekdays (Monday to Friday) and weekend days;
- the span in hours (days × 24);
- an approximate figure in months and years, using the average Gregorian month of 30.436875 days and year of 365.2425 days.
All dates are calendar dates, so time zones and daylight-saving changes never add or remove a day.
Start and end dates: which days are counted?
The default count works like a day counter on a calendar: it counts how many times you move to the next day. From 1 March to 2 March that is 1 day, and from 1 January to 31 December 2026 it is 364 days (365 in a leap year).
When you tick Include the end date, both endpoints count, so the same periods become 2 days and 365 days. The weekday and weekend counts follow the same rule: they cover exactly the days included in the result.
Examples
| Start | End | Result |
|---|---|---|
| 1 March 2026 | 2 March 2026 | 1 day (2 with the end date) |
| 1 January 2026 | 31 December 2026 | 364 days = 52 weeks (365 with the end date) |
| 1 June 2026 | 30 June 2026 | 29 days: 21 weekdays, 8 weekend days |
| 10 February 2026 | 1 September 2026 | 203 days = 29 weeks = 6 months, 22 days |
In the June example, 1 June 2026 is a Monday. Without the end date the days counted are 1 to 29 June: four full weeks (20 weekdays and 8 weekend days) plus Monday 29 June, so 21 weekdays. Including 30 June adds a Tuesday, giving 30 days, 22 weekdays, and exactly 1 month in the breakdown.
For the last example, 203 ÷ 30.436875 ≈ 6.67 months and 203 ÷ 365.2425 ≈ 0.56 years.
Common uses
- Counting the days until an exam, a trip or a due date.
- Working out how many days have passed since a start date, a purchase or an event.
- Measuring the time between dates for a notice period, a rental or a project.
- Checking how many weekdays fall in a period before planning work.
Good to know
- The weekday count only excludes Saturdays and Sundays. To skip public holidays or use a different weekend, count business days instead.
- To find the date that is a number of days away, add or subtract days from a date.
- For a live count to a specific moment, create a countdown to any date.
- The Gregorian calendar is applied to all dates, including historical ones, so very old dates follow today’s leap-year rules.