Three ways to count the same gap
"How many days between" has more than one right answer depending on what you are counting. Calendar days is the plain difference. Including the end date adds one, which is how you count the days of a trip or a hotel stay that you are present for. Workdays counts only Monday to Friday, which is how notice periods and delivery times are usually quoted.
| From | To | Days | Incl. end date | Weekdays (Mon–Fri) |
|---|---|---|---|---|
| Mon, Sep 28, 2026 | Fri, Oct 2, 2026 | 4 | 5 | 4 (5 incl. end) |
| Jan 1, 2026 | Jan 1, 2027 | 365 | 366 | 261 |
| Sat, Oct 3, 2026 | Mon, Oct 5, 2026 | 2 | 3 | 0 (1 incl. end) |
Holidays are not removed
Public holidays differ by country, state and employer, so the workday count does not subtract them. For a US federal calendar, 2026 has 261 weekdays and 11 federal holidays that land on (or are observed on) a weekday, which leaves 250 working days.
Weeks and months
Weeks are days ÷ 7, shown as full weeks plus leftover days. Months are whole calendar months from the start date, then leftover days, the same way an exact age is counted. When the start day does not exist in a shorter month, the month mark falls on that month's last day, so Jan 31 → Feb 28 counts as exactly 1 month.
What people ask next
- How many hours did I work this week? once you know the days.
- How many days have we been together? for the dates that matter most.
How we calculate
Days = end − start in calendar days (+1 if the end date is included). Workdays = Monday–Friday dates in that span. Public holidays are not removed.
- Public holidays differ by country, state and employer, so they are not subtracted.
Every formula is checked by automated tests. Methodology · Updated