Days Between Dates Calculator

Calculate the date difference in days and weeks

Choose a start date and end date to calculate the calendar-day difference between them. The result also shows full weeks and leftover days, so you can read an interval such as 17 days as 2 weeks and 3 days. The calculator works with date-only values and does not depend on the time of day.

Count weekdays for a date range

The weekday total counts Monday through Friday and skips Saturday and Sunday. It can help with an initial workday estimate for a project, school period, or deadline, but it does not know public holidays, company closures, or your personal schedule. Check those separately when they affect your dates.

Elapsed days versus inclusive counting

Elapsed days measure the amount of time from one date to another. An inclusive count treats both endpoint dates as counted dates. Use the checkbox to match the convention required by your trip, event, or form; date ranges and forms do not all use the same counting convention.

Use the calculator as a days-until countdown

To find how many days remain until an event, set the start date to today and the end date to the event date. You can also reverse the task and measure how long ago a past date occurred. The calculator rejects an end date earlier than the start date so the interval remains easy to interpret.

Elapsed days are not the same as inclusive days

Elapsed days run from the start date up to, but not including, the end date. Monday 5 January 2026 through Monday 12 January 2026 is 7 elapsed days. The start Monday is the beginning of the span, and the end Monday is the boundary you have not counted as an extra day. Turn on “include the end date” and the calendar count becomes 8, because both Mondays are now counted dates. Hotel nights, age spans, and “days until” deadlines usually want the elapsed count. A rental that charges for every calendar date you hold the item, including the return date, may want the inclusive count. The checkbox exists because forms do not agree. Same start and end date is 0 elapsed days and 1 inclusive day.

Weekdays, weeks, and leftover days

The weekday total counts Monday through Friday inside the interval you selected and skips Saturday and Sunday. In the 5 January to 12 January elapsed example, the weekdays are Monday through Friday of that week, which is 5, and the ending Monday is outside the elapsed interval. Including the end date adds that Monday and makes 6 weekdays. Public holidays, company shutdowns, and a four-day schedule are not removed. If Friday is a holiday, subtract it yourself. Full weeks and leftover days are the same calendar span rewritten: 17 elapsed days is 2 weeks and 3 days. That rewrite does not drop weekends. It only groups the calendar days into sevens.

Days until, days since, and date order

Set the start date to today and the end date to a deadline to see days remaining. Leave the inclusive option off when “how many days until” means the nights or midnights you still have to cross. A deadline tomorrow is 1 elapsed day. A deadline today is 0 elapsed days, which means the date has arrived, not that the count is broken. To measure how long ago a date was, put the earlier date in start and today in end. The calculator rejects an end date that falls before the start so the interval stays in one direction. Swap the dates rather than reading a negative number. Time of day does not change the result. A date-only span ignores hours, minutes, and daylight-saving shifts.

Worked examples you can type

Start Friday 1 May 2026, end Monday 4 May 2026. Elapsed calendar days are 3. Weekdays in that elapsed span are Friday only, because Saturday and Sunday are skipped and Monday is the boundary, so the weekday count is 1. Include the end date and the calendar count is 4 while weekdays become 2, Friday and Monday. A project that says “three days later” usually means the elapsed reading. A project that says “count every weekday we will be open, including the delivery day” needs the inclusive reading and still needs you to remove any holiday by hand.

How this differs from an age

Days between dates do not know about birthdays. An age in years, months, and days borrows across months of unequal length and turns over on an anniversary. This page never does that. A span of 400 days is 400 days, 57 weeks and 1 day, and a weekday count that depends on which weekday you started. It is not “1 year and 35 days” unless you impose a year length yourself. Use the age calculator when one date is a birth date and you want completed years plus the next birthday. Use the chronological age calculator when a form wants years, months, and days on an assessment date. Use this page for trips, notice periods, countdowns, and any two dates that are not an age.

Leap days and month length

The calendar already contains the leap day, so a span that crosses 29 February in a leap year is one day longer than the same month-and-day pair in a common year. You do not add that day manually. From 1 February 2024 to 1 March 2024 is 29 elapsed days because 2024 includes 29 February. From 1 February 2025 to 1 March 2025 is 28 elapsed days. Month length is the same idea: 1 January to 1 February is 31 elapsed days, and 1 April to 1 May is 30. Counting “30 days a month” by hand will miss those. The inclusive checkbox still adds one to whichever elapsed count the calendar produced. It does not change February’s length.

Notice periods and “within N days”

Contracts often say “within 14 days” or “30 days’ notice.” The phrase does not tell you whether the start day counts. If notice is given on 1 March and must land within 14 elapsed days, the deadline date is 15 March, because the span from the 1st to the 15th is 14 elapsed days. If the clause counts the day of notice as day 1, the inclusive reading points at 14 March. This calculator will show both once you set the checkbox. It will not interpret the clause. Quote the sentence next to the result you keep. Business-day notice is a third variant: start from the weekday count, then add back any holiday the contract says is not a business day. The weekday total is only Monday to Friday. A contract that says “business days” and then defines them differently needs that definition applied by hand.

Trips, rentals, and the night you do not count

A trip that departs 10 June and returns 17 June is 7 elapsed days if you mean the span, and 8 inclusive dates if every calendar date away from home counts. Hotel stays are usually nights, which track elapsed days: check-in on the 10th and check-out on the 17th is 7 nights. A car rental that charges each calendar date, including both the pickup date and the return date, tracks the inclusive count. Write down which one you selected before you compare the result with a booking site. The booking site may be counting nights while you are counting dates. The numbers can differ by one without either page being broken. Weekdays matter when the rental office is closed on Sunday and the return would fall on a closed day. The calculator will still count that Sunday as a calendar day. It will only exclude it from the weekday total.

Two Mondays should differ by whole weeks

Two dates that share a weekday are a whole number of weeks apart in elapsed days. A Monday and the Monday 21 days later are exactly 3 weeks apart. The elapsed weekday count is 15, because each week contributes Monday through Friday and the ending Monday is not included. Include the end date and you add that Monday, making 16 weekdays and 22 calendar days. If your elapsed count between two Mondays is not divisible by 7, one date is not the weekday you think it is, or a year is wrong. Use that check before you publish a schedule from the result.

School terms and project calendars

A term from 2 September to 18 December can be described as elapsed days, as weeks plus leftover days, and as weekdays. The weekday figure is a ceiling on class days, not the number of sessions. In-service days, holidays, and cancelled sessions come off that ceiling. A project plan that says “10 weeks” may mean 70 calendar days or 50 weekdays. This page lets you see both from the same pair of dates so the plan and the calendar can be compared. It does not build a Gantt chart, and it does not skip a company shutdown week unless those dates are outside your start and end. If the shutdown sits in the middle, subtract those days from the result you publish. Keep the start and end dates in the note so the subtraction can be audited.

Related terms and how calculations work

Elapsed date difference

The time from the start date up to, but not including, the end date. The same start and end date has zero elapsed days.

Inclusive day count

A count that includes the end date as a calendar day. In this tool, enabling the option adds one day to the elapsed count.

Weekday count

The number of Monday-through-Friday dates in the counted interval. Saturdays and Sundays are skipped; public holidays and custom nonworking days are not excluded.

Date interval

A span between two calendar dates. This calculator uses date-only values, so time of day and daylight-saving clock changes do not change the result.

Practical examples

Frequently asked questions