Are both the start and end dates included?

Yes. The calculator counts inclusively — if you enter January 1 as start and January 1 as end, you get 1 calendar day and either 0 or 1 business day depending on whether it is a weekday.

Does "net 30" mean calendar days or business days?

"Net 30" in US business invoicing typically means 30 calendar days, not business days. However, some contracts specify "30 business days." Always check the contract language — 30 calendar days is roughly 21–22 business days.

Are public holidays excluded?

No. The tool counts Mon–Fri only. If your contract excludes public holidays, subtract the number of holidays that fall in your date range from the business day count manually.

guide

How to Count Business Days Between Dates — Free (2026)

By Rui Barreira · Last updated: 18 June 2026

Count the number of business days between any two dates with the brevio Business Days Calculator — free, no signup, runs entirely in your browser. Enter a start date and end date to get the total calendar days, business days (Monday–Friday), and weekend days.

Business day counting comes up constantly in contracts, project timelines, delivery estimates, and regulatory deadlines. "Net 30 business days" means something very different from "30 calendar days" depending on weekends and holidays.

How to Use the Tool

Enter a start date. Use the date picker to select the beginning of your period.
Enter an end date. Both dates are inclusive — the start and end day are both counted.
Click Calculate. The tool returns calendar days, business days, and weekend days.
Subtract public holidays manually if your country or company observes them as non-working days — the tool counts Mon–Fri only.

How Business Days Are Counted

The algorithm iterates through every calendar day from start to end (inclusive) and counts each Monday, Tuesday, Wednesday, Thursday, and Friday as a business day, and each Saturday and Sunday as a weekend day. The total calendar day count includes all seven days.

A common formula for quick estimation is: count complete weeks between the dates (multiply by 5), then add the business days in the partial weeks at each end. This works well for ranges of several weeks but the tool is more precise for short or edge-case ranges.

Public holidays are not automatically excluded because they vary by country, region, and company. If you are calculating a contract deadline that excludes US federal holidays (Labor Day, Thanksgiving, etc.), subtract the number of holidays that fall in your date range from the business day count.

Frequently Asked Questions

Are both the start and end dates included?: Yes. The calculator counts inclusively — if you enter January 1 as start and January 1 as end, you get 1 calendar day and either 0 or 1 business day depending on whether it is a weekday.
How do I add business days to a date?: To find a date that is 10 business days after a given date, add 14 calendar days and then check whether the result falls on a weekend — if it does, add 1 or 2 more days. A simpler approach is to use the tool: set your start date and experiment with end dates until the business day count matches your target.
Does net 30 mean calendar days or business days?: "Net 30" in US business invoicing typically means 30 calendar days, not business days. However, some contracts specify "30 business days." Always check the contract language — 30 calendar days is roughly 21–22 business days, a significant difference for deadlines.

Frequently Asked Questions

Are both the start and end dates included?: Yes. The calculator counts inclusively — if you enter January 1 as start and January 1 as end, you get 1 calendar day and either 0 or 1 business day depending on whether it is a weekday.
Does "net 30" mean calendar days or business days?: "Net 30" in US business invoicing typically means 30 calendar days, not business days. However, some contracts specify "30 business days." Always check the contract language — 30 calendar days is roughly 21–22 business days.
Are public holidays excluded?: No. The tool counts Mon–Fri only. If your contract excludes public holidays, subtract the number of holidays that fall in your date range from the business day count manually.