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Percentage calculator
Calculate percentages, proportions and changes.
Everyday math
Date calculator
Find the number of calendar days between dates.
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How do calendar days differ from business days?
Calendar days include weekends. Business days in this tool count Monday through Friday, without excluding public holidays. The start date is excluded by default and can optionally be included.
| Range in 2026 | Exclude start | Include start |
|---|---|---|
| Sep 11 (Fri)–14 (Mon): calendar | 3 days | 4 days |
| Same range: business | 1 day | 2 days |
| Sep 12 (Sat)–13 (Sun): business | 0 days | 0 days |
| Sep 14 (Mon) only: business | 0 days | 1 day |
For delivery or contractual deadlines, check the relevant closure dates and counting rules separately. This tool does not add N days to a date or automatically look up national holidays.
Compare changes between periods with the percentage calculator.How to use
- Choose a start and end date, in chronological order.
- Select calendar days or business days, and optionally include the start date.
- Calculate. Business days exclude weekends, not public holidays.
How it works
Calendar days = end date minus start date, plus one if including the start. Business days count Monday–Friday in the same range. The end is in the range but counts only if a weekday.
Common questions
Are public holidays excluded?
No. Only Saturday and Sunday are excluded. National holidays and company closures are not applied.
What about the same date?
Excluding the start gives zero. Including it gives one calendar day; business mode gives one on a weekday or zero on a weekend.
Can I add days to a date?
No. This tool counts between two dates. Use today as the start to count down to a future date.
Does daylight saving affect the result?
No. Calendar dates are counted independently of local clock changes.