How do I count business days?

List every calendar date in the range, drop the weekends (Saturday and Sunday by default), then drop any holiday dates you have added that fall on a weekday. The number left is your business-day count. The Business Days Calculator does this for you, inclusively.

Are weekends included in business days?

No. Business days exclude weekends. This site uses Saturday and Sunday as the default weekend, so only Monday through Friday are counted as business days.

Does the start date count?

In the between-dates mode, yes — both the start and end dates are counted when they are working days (inclusive). When adding or subtracting business days, no — counting starts from the next or previous calendar date, so the starting date itself is not counted.

How do holidays affect business days?

Add the holiday dates that apply to you and they are removed from the count when they fall on a weekday. A holiday on a weekend is not double-counted — it is already excluded by the weekend rule.

Dates

Counting Business Days

Business days are the working days in a span, with weekends and selected holidays removed. This guide covers what counts as a business day here, inclusive vs exclusive counting, how holidays fit in, and the mistakes that throw working-day counts off.

What a business day means here

On this site, a business day is a Monday-to-Friday weekday. Saturday and Sunday are treated as the weekend and excluded by default. This is the most common convention, but weekend definitions vary around the world — some regions observe a Friday–Saturday or Sunday–Monday weekend — so adjust your expectations if your situation uses a different pattern.

This guide explains the maths, not any jurisdiction's legal definition of a working day or public holiday.

Inclusive vs exclusive counting

The Business Days Calculator counts business days between two dates inclusively — both the start and end dates are counted when they are working days. Monday to Friday of the same week is 5 business days. A single date counted against itself is 1 business day if it is a weekday, or 0 if it falls on a weekend.

Inclusive counting is the natural choice for "how many working days are in this range?". If you instead want elapsed working days — like the number of working days that pass after a start date — use the Add / Subtract mode, where counting starts from the next (or previous) calendar date.

A worked example

Count the business days from Monday 3 August 2026 to Friday 7 August 2026, with weekends excluded and no holidays added:

Monday 3 — weekday, counted (1).
Tuesday 4 — counted (2).
Wednesday 5 — counted (3).
Thursday 6 — counted (4).
Friday 7 — counted (5).

The total is 5 business days inclusive. The same range is 5 calendar days too, because no weekend falls inside it. Stretch it to Monday 3 → Monday 10 and you get 6 business days (the second Monday is counted) across 8 calendar days — the weekend of 8–9 August is excluded.

Weekends

Weekends are removed from the count by default. A two-week span is 14 calendar days but typically only 10 business days, because the two Saturdays and two Sundays are dropped. If you need the total calendar-day difference instead, use the Days Between Dates Calculator.

Manually excluded holidays

Holidays vary by country, region and organisation, so the calculator does not assume any jurisdiction's public holidays — you add the specific dates that apply to you. Tick "Exclude holidays" and enter each date; any that fall on a weekday are also removed from the total.

Holiday-on-weekend double-counting: a holiday that lands on a Saturday or Sunday is already removed by the weekend rule, so it is not subtracted a second time. Only holidays that fall on a weekday reduce the business-day total. This keeps the count honest — without this rule, a Saturday holiday would wrongly knock another day off.

Adding business days to a date

To find a future working date, add a number of business days to a starting date. Counting starts after the starting date — the starting date itself is not counted. Starting on a Monday, +1 business day is Tuesday. Starting on a Friday, +1 business day is the following Monday. Starting on a Monday, +5 business days is the next Monday (Tuesday, Wednesday, Thursday, Friday, then Monday).

The Business Days Calculator's "Add / Subtract Business Days" mode does this and skips any holidays you have added. For adding plain calendar days, weeks, months or years instead, use the Date Add & Subtract Calculator.

Subtracting business days

Subtraction works the same way in reverse. Counting starts from the day before the starting date and moves backwards, skipping weekends and holidays. Monday − 1 business day is the previous Friday. Friday − 1 business day is Thursday.

Business days vs calendar days

Calendar days include every date in the range, weekends included. Business days exclude configured weekend days and any selected holidays. The two answers can be quite different: a 30-calendar-day month is usually around 21–22 business days. Use calendar days for elapsed time and deadlines measured in raw days; use business days for working time, lead times and "how many working days do I have?" questions.

Common mistakes

Counting weekends as business days. Saturday and Sunday are not business days, so a Monday-to-Friday week is 5, not 7.
Double-counting holidays on weekends. A holiday on a Saturday is already excluded by the weekend rule — don't subtract it again.
Including the starting date when adding business days. Monday + 1 business day is Tuesday, not Monday. Counting starts the next day.
Assuming public holidays are universal. Public holidays differ by country, region and employer. Enter the dates that apply to your situation.
Confusing inclusive and exclusive counts. The between-dates mode counts both endpoints; the add/subtract mode does not count the starting date. Pick the mode that matches your question.
Forgetting month and year boundaries. Counts cross month and year edges one calendar date at a time, so there is no rounding error — but only if you count each date rather than approximating with weeks.

FAQs

How do I count business days?: List every calendar date in the range, drop the weekends (Saturday and Sunday by default), then drop any holiday dates you have added that fall on a weekday. The number left is your business-day count. The Business Days Calculator does this for you, inclusively.
Are weekends included in business days?: No. Business days exclude weekends. This site uses Saturday and Sunday as the default weekend, so only Monday through Friday are counted as business days.
Does the start date count?: In the between-dates mode, yes — both the start and end dates are counted when they are working days (inclusive). When adding or subtracting business days, no — counting starts from the next or previous calendar date, so the starting date itself is not counted.
How do holidays affect business days?: Add the holiday dates that apply to you and they are removed from the count when they fall on a weekday. A holiday on a weekend is not double-counted — it is already excluded by the weekend rule.
What is the difference between calendar days and business days?: Calendar days include every date in the range, weekends included. Business days exclude weekends and any selected holidays. A two-week span is 14 calendar days but typically 10 business days. Use the Days Between Dates Calculator for calendar days and the Business Days Calculator for working days.