Business Days Calculator: Weekdays Between Dates

How many working days are there between two dates?

Short answer: The Business Days Calculator counts every Monday-to-Friday date from your start date through your end date, both included, and then subtracts the holiday dates you type in. December 21, 2026 to January 8, 2027 with two listed holidays gives 19 calendar days, 15 weekdays and 13 working days. The tool never looks holidays up on its own.

Key facts

The Business Days Calculator treats both the start date and the end date as part of the range, so a range with the same start and end counts as one calendar day.
Saturday and Sunday are always weekends. The tool has no setting for a different workweek.
Holidays come only from the box labeled "Holiday dates to exclude". An empty box means only weekends are removed.
The holiday box takes one date per line in YYYY-MM-DD format. Blank lines and spaces around a date are ignored.
A malformed or impossible date, such as 2026-02-30, stops the calculation and the tool names the bad value.
The end date must be on or after the start date, and the range may not exceed 10,000 days, which is a little over 27 years.
The calculation runs in your browser with no network requests, and both date fields start on today's date.

How to use

Pick a date in "Start date (inclusive)" and another in "End date (inclusive)".
Optional: type the days off you want removed into "Holiday dates to exclude", one per line, for example 2026-12-25.
Press "Count days".
Read "Working days" in the highlighted row. The other three rows show how the number was reached.

Formula and logic

The tool walks through the range one calendar date at a time, using plain calendar dates rather than clock times, so daylight saving changes and your time zone cannot shift the answer.

calendar days = (end date - start date) in days + 1
weekdays      = dates in the range that are Monday to Friday
working days  = weekdays that are not in your holiday list
holidays excluded = weekdays - working days

Every result is a whole number, so nothing is rounded. "Holidays excluded" is the number of listed dates that actually removed a weekday, not the number of lines you typed.

Worked example

Every row below was produced by running the same logic the calculator uses.

Start	End	Holidays entered	Calendar days	Weekdays	Working days	Holidays excluded
2026-12-21	2027-01-08	2026-12-25, 2027-01-01	19	15	13	2
2026-11-02	2026-11-06	none	5	5	5	0
2026-11-01	2026-11-30	2026-11-26, 2026-11-27	30	21	19	2
2026-11-27	2026-11-29	2026-11-28	3	1	1	0
2026-12-24	2026-12-24	2026-12-24	1	1	0	1

Why a holiday sometimes removes nothing

Look at the fourth row above. November 28, 2026 is a Saturday, so it was already gone as a weekend, and the tool reports 0 holidays excluded.

The same happens when a listed date falls outside the range, and a date entered twice counts once. If your count looks one day too high, check whether your day off landed on a weekend, and add the observed Monday or Friday separately.

Inclusive count versus "within 5 business days"

This tool answers "how many working days sit inside this span, ends included?" A contract that says "within five business days of receipt" asks something different. Many such clauses do not count the day of receipt, so the same dates can give a count one lower than the calculator shows.

If your rule skips the first day, move the start date forward by one day before you press the button. For anything with legal or financial weight, read the clause itself, because the tool cannot know which convention applies.

Planning leave and projects

Say you want to take December 21 to January 8 off and your company closes on December 25 and January 1. The example table shows you would spend 13 working days away, not 19. That is the number to deduct from a leave balance if your employer counts working days.

For project work, pick the start and end of a sprint or release window, add the days when the office is shut, and use "Working days" as the capacity ceiling before you subtract meetings, sick days and anything else.

Common input mistakes

Writing 12/25/2026 or 25.12.2026 in the holiday box. Only 2026-12-25 style is accepted, with a leading zero on single-digit months and days.
Swapping the two dates. The tool will not reorder them and shows an error instead.
Typing a year wrong, so the holiday lands outside the range and changes nothing.
Reading "Weekdays before holidays" as the final answer. The final answer is "Working days".

What this tool does not do

The Business Days Calculator does not know any country's public holidays and will not add them for you.
It does not add or subtract business days from a date to produce a new deadline date. It only counts the days within a range.
It does not handle half days, shift work, or a workweek that includes Saturday or excludes Friday.
It does not apply contract, court or carrier rules about cut-off times and rolling a deadline forward.

Frequently asked questions

Are the start and end dates included in the business day count?

Yes. Both dates are part of the range, and each one adds a working day if it is a Monday to Friday that is not in your holiday list.

Does the calculator exclude public holidays automatically?

No. It does not know your country, region or employer. Type every holiday you want removed into the holiday box; with the box empty, only Saturdays and Sundays are excluded.

Which days does the calculator treat as the weekend?

Saturday and Sunday. The workweek is fixed at Monday to Friday, so schedules with a different rest day need to be handled by hand.

What date format should I use for holidays?

Use YYYY-MM-DD, one date per line, for example 2026-12-25. Any other format or a date that does not exist stops the calculation with an error that names the invalid date.

What happens if the start date is later than the end date?

The calculator shows an error and counts nothing. It does not swap the dates for you, so put the earlier date in the start field.

Does a holiday on a Saturday or Sunday subtract another day?

No. A weekend is already excluded, so the holiday adds nothing to "Holidays excluded". If your employer gives a substitute weekday off, enter that date as well.

How long a date range can I check?

Up to 10,000 days, roughly 27 years, counting both end dates. A longer range returns an error asking you to pick a shorter one.

Can I use the result as a legal or delivery deadline?

Use it as a planning estimate only. The tool does not know your contract's counting rule, local holiday calendar or cut-off time, so check the governing terms before relying on a date.

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Last reviewed: October 21, 2026