Date Difference Calculator

Pick two dates and read the days between them, as a plain count, as years, months and days, and as weeks, hours and a fraction of a year, with the option to count both ends. Business days are counted without Saturdays and Sundays and, if you like, without US federal holidays for 2026 and 2027 as the Office of Personnel Management lists them, with the holidays in the span named. Switch to Add or subtract days to find the date a number of days, business days, weeks, months or years before or after a start date.

How it works

Date Difference Calculator is a web page that does its work on your own device. Everything you type or choose is worked out by your browser and never sent to a server, so nothing is stored and there is nothing to delete. There is no account, no sign-up and no limit on how often you use it.

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Days Between Dates · Business Days Calculator

Counting days between dates

The number of days between two dates is the plain count of midnights crossed: from Monday to Wednesday is two days. That is how most things are measured, deadlines, interest, ages, rentals. Some counts include both ends, a hotel's "nights" versus a conference's "days", or a notice period that counts the day it is given; tick Count the end date too for those. The result is also given as years, months and days, counted the way ages are, with the months taken at their real lengths, and as weeks, hours and a fraction of a year.

Business days and holidays

Business days skip Saturdays and Sundays, and, if you tick it, the US federal holidays as the Office of Personnel Management lists them for 2026 and 2027 (OPM, Federal Holidays, read 5 October 2026), including the observed dates when a holiday falls on a weekend, such as Friday 3 July 2026 for Independence Day. Banks, courts and government offices follow these; private employers and other countries have their own, so check your own calendar for anything that must be exact. The holidays that fell inside the span are named under the result.

Adding and subtracting

Add or subtract days lands on the date a number of days, business days, weeks, months or years from a start date: a 30-day return window, a 90-day probation, ten working days to reply, a lease that ends in three years. Months and years keep the day of the month where they can; when it does not exist, 31 January plus one month, the last day of the month is used, which is the convention most contracts and calendars follow. Business days count forward or back over weekends and holidays.

What this tool does not do

• It does not know holidays outside the US federal list, or state and company holidays; untick the holiday option and subtract them yourself.
• It does not count hours or minutes; dates are whole days in the calendar, with no time zone involved.

What it does

• Days between two dates, inclusive or not, as years, months and days too
• Business days skipping weekends and US federal holidays, which are named
• Add or subtract days, business days, weeks, months or years
• Weeks, hours and years as a fraction, for the same span
• From today and To today buttons, swap, and the direction handled either way
• End-of-month rule for months and years, as contracts use it
• No upload, no account, no sign-up

Questions

How many days are between two dates?

Set From and To and read the big number: the count of days from the first date to the second, not counting the first day, which is how deadlines and interest are usually counted. Tick Count the end date too to include both days.

How are business days counted?

Every day from the day after the start date to the end date that is not a Saturday or Sunday, and not a US federal holiday if that option is ticked. Tick Count the end date too and the start day is included when it is a working day.

Which holidays are skipped?

The US federal holidays as observed, from the Office of Personnel Management's lists for 2026 and 2027 (read 5 October 2026): New Year's Day, Martin Luther King Jr. Day, Washington's Birthday, Memorial Day, Juneteenth, Independence Day, Labor Day, Columbus Day, Veterans Day, Thanksgiving and Christmas, on their observed dates when they fall on a weekend. State, company and other countries' holidays are not included.

How is the years, months and days figure worked out?

The way ages are: whole years first, then whole months at their real lengths, then the days left over. 31 January to 1 March is 1 month and 1 day.

What happens when I add a month to 31 January?

The result is the last day of February, since February has no 31st. Months and years keep the day of the month where it exists and otherwise use the last day, which is the usual rule in contracts and calendars.

Can I count business days forward from a date?

Yes. Choose Add or subtract days, set the unit to business days and the number, and the date that many working days ahead (or back, with before) is shown, skipping weekends and, if ticked, holidays.

Does it use my time zone?

No. Dates are whole calendar days, so there is no time of day or zone involved; the same two dates give the same answer anywhere.

Is it free?

Yes, completely free, with no sign-up.

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