About Business Days Calculator
Enter a start date and an end date and this tool counts the working days in between, along with the weekend days, the total days and the equivalent in business weeks. Monday to Friday count by default; tick Saturday or Sunday if your week includes them. The end date is included unless you untick that option. Public holidays are not removed, so subtract the ones that apply to you. As a rule of thumb, 5 business days take 7 calendar days and 10 business days take 14, because each full working week carries a weekend with it.
How long is 1 to 30 business days in calendar days
Monday to Friday week, no holidays, counting from a weekday with the start day not counted.
| Business days | Calendar days | When the longer figure applies |
|---|---|---|
| 1 | 1 or 3 | Start on a Friday |
| 2 | 2 or 4 | Start on a Thursday or Friday |
| 3 | 3 or 5 | Start on a Wednesday, Thursday or Friday |
| 4 | 4 or 6 | Start on any weekday except Monday |
| 5 | 7 | Always one week |
| 7 | 9 or 11 | Start on a Thursday or Friday |
| 10 | 14 | Always two weeks |
| 15 | 21 | Always three weeks |
| 20 | 28 | Always four weeks |
| 30 | 42 | Always six weeks |
For ranges, combine the rows: 1 to 3 business days is 1 to 5 calendar days, 5 to 7 is 7 to 11, and 5 to 10 is 7 to 14.
Calendar days to business days conversion
How many Monday to Friday days fit in a span of consecutive calendar days. A range is shown where the answer depends on the weekday the span starts on.
| Calendar days | Business days |
|---|---|
| 7 | 5 |
| 10 | 6 to 8 |
| 14 | 10 |
| 21 | 15 |
| 28 | 20 |
| 30 | 20 to 22 |
| 31 | 21 to 23 |
| 45 | 31 to 33 |
| 60 | 42 to 44 |
| 90 | 64 to 65 |
| 180 | 128 to 130 |
| 365 | 260 or 261 |
Business days in each month of 2026 and 2027
Weekdays from the first to the last day of each month, both included, before any holidays.
| Month | 2026 | 2027 |
|---|---|---|
| January | 22 | 21 |
| February | 20 | 20 |
| March | 22 | 23 |
| April | 22 | 22 |
| May | 21 | 21 |
| June | 22 | 22 |
| July | 23 | 22 |
| August | 21 | 22 |
| September | 22 | 22 |
| October | 22 | 21 |
| November | 21 | 22 |
| December | 23 | 23 |
| Full year | 261 | 261 |
Quarters of 2026: Q1 has 64 weekdays, Q2 has 65, Q3 has 66 and Q4 has 66.
Worked examples: counting working days between two dates
One working week
Start date October 5, 2026 (Monday); End date October 9, 2026 (Friday); end date included
5 business days, 0 weekend days, 5 total days, 1 business week.
Two weeks, end date included
Start date October 8, 2026; End date October 22, 2026; end date included
11 business days, 4 weekend days, 15 total days, 2.2 business weeks.
The same two weeks as a gap
Start date October 8, 2026; End date October 22, 2026; Include the end date in the count unticked
10 business days, 4 weekend days, 14 total days, 2 business weeks.
Unticking the box drops the end date from the count. Between two weekdays that gives the same figure as a quoted 10 business days, where the first day is not counted.
Six-day working week
Start date October 8, 2026; End date October 22, 2026; Count Saturday as a working day ticked
13 business days, 2 weekend days, 15 total days, 2.6 business weeks.
Working days left before Christmas
Start date October 8, 2026; End date December 25, 2026; end date included
57 business days, 22 weekend days, 79 total days, 11.4 business weeks.
Take off the holidays you observe in that stretch, including December 25 itself if it is one.
Including the end date, and where holidays fit
With the end date included, both the first and the last day are counted. That is right for a period that is worked through: leave from Monday to Friday is 5 days, not 4. It also matches the NETWORKDAYS function in Excel and Google Sheets, which counts both ends.
Untick the option when you are measuring from an event to a deadline. Delivery estimates and clauses worded as within 10 business days of receipt do not count the day of the order or receipt; day 1 is the next working day. The tool gets there by leaving out the end date instead of the start date. The figure is the same whenever both dates are working days. It differs by one when exactly one of the two dates is a weekend day: Saturday, October 10 to Monday, October 12, 2026 shows 0 business days with the box unticked, although Monday would be day 1 of a delivery estimate.
Holidays are left out on purpose. There are 11 US federal holidays a year and 8 standard bank holidays in England and Wales, and states, regions and employers add or drop days of their own. Count the working days here, then subtract each holiday that lands on a working day in your range. A holiday that falls on a Saturday or Sunday is already excluded with the weekend.
Business weeks is the business day count divided by 5 and rounded to one decimal place, whichever weekend boxes are ticked.
How to use it
- 1
Enter the Start date and the End date. They can be in either order.
- 2
Tick Count Saturday as a working day or Count Sunday as a working day if those days are worked.
- 3
Leave Include the end date in the count ticked to count both the first and last day, or untick it to measure the gap between two dates.
- 4
Read Business days, Weekend days, Total days and Business weeks in the Working days panel.
- 5
Subtract any public holidays that fall on a working day inside your range.