Days between dates calculator

In short: The days between two dates is the later date minus the earlier one, counted on the calendar: from 1 January to 31 December 2026 is 364 days, or 365 when the end date counts too. The calculator also shows the span as weeks, as months and as weekdays, and finds the date a number of days away.

Last updated 10 October 2026

How days between two dates are counted

1. Take the later date minus the earlier one. The start day is day zero, so Monday 5 October to Friday 9 October 2026 is 4 days.
2. Decide whether the end date counts. For a hotel stay, a rental or a course, both days are often counted: the same Monday to Friday is then 5 days. Tick the box to switch.
3. Read the same span other ways. 76 days from Saturday, 10 October 2026 to Christmas Day 2026 is 10 weeks and 6 days, or 2 months and 15 days, of which 54 are weekdays and 22 fall on a weekend.

Each figure is computed on calendar dates in the browser, so a clock change for daylight saving never shifts a count, and nothing you type leaves your device. If both dates are the same day, the difference is 0; tick the box to count it as one day.

How many days until a date, and days from today

The start date is set to today when the page opens and the end date to 31 December, so the first answer is the days left in the year. Change the end date to a birthday, a deadline or a holiday to see how many days until it, or switch to Add or subtract days to find the date a number of days from today: 90 days after Saturday, 10 October 2026 is Friday, 8 January 2027, which is 12 weeks and 6 days or 2 months and 29 days, and 14 days before it is Saturday, 26 September 2026. The table shows some spans people look up often, counted from Saturday, 10 October 2026.

Weeks between and months between two dates

Weeks are simple: divide the days by 7 and keep the remainder as days, so 76 days is 10 weeks and 6 days. Months are not a fixed length, so the calculator follows the calendar instead: a month is complete when the same day of the month comes round again. From 15 January to 15 February is 1 month whether February has 28 or 29 days. From 31 January, February never reaches a 31st, so 31 January to 28 February 2026 is 28 days and 31 January to 1 March 2026 is 1 month and 1 day, counted through 28 February, the last day February has. Whole years are shown first once the span reaches twelve months, so a span of 365 days from 1 January 2026 with the end date counted reads 1 year.

Other tools can give a different months figure for the same dates, because some count a month as 30 days or as a twelfth of a year. Use the calendar days figure when the exact count matters, for example in a contract, and the months figure as a readable summary.

Leap years and the end of February

A leap year adds 29 February, which makes any span across it one day longer: 28 February to 1 March is 2 days in 2028 and 1 day in 2027. A year is a leap year when it divides by 4, except that century years are leap years only when they divide by 400. 2000 was a leap year, 2100 will not be, and the next leap years are 2028 and 2032. The calculator reads the leap days from the calendar, so a span of several years is exact to the day, and adding 365 days to a date that crosses a 29 February lands one day short of the anniversary.

Working days instead of calendar days

The result shows how many of the days are weekdays, Monday to Friday, and how many fall on a weekend, which is often enough to plan around. For a deadline that skips public holidays, or a weekend other than Saturday and Sunday, use the business days calculator, which counts working days between two dates and adds business days to a date. The working days pages list every month of the year with the US federal holidays already taken out, and the week number calculator tells you which week of the year a date falls in.