📅 Date Calculator
Days between two dates — including business days — or add days to a date.
How to use the Date Calculator
Add or subtract days, weeks, months and years from any date, or find the number of days between two dates including business days.
How it works
Calendar arithmetic is less obvious than it looks. Months have different lengths, so adding one month to 31 January lands on 28 or 29 February rather than 3 March. Business-day calculations must skip weekends and public holidays, and because holidays differ by country and change year to year, the result depends on which calendar you apply. Daylight saving transitions affect a 24-hour day that is actually 23 or 25 hours long.
When to use it
Use it to plan project deadlines, count down to a delivery or exam date, work out how many working days a task has, or find a date a required number of days from now.
Worked example
Days between 1 March 2026 and 1 April 2026:
| Measure | Value |
|---|---|
| Calendar days | 31 |
| Weekends in range | 8 |
| Business days | 23 |
| Weeks and 3 days | 4 weeks, 3 days |
Assumptions and limitations
Public holidays are not included; add them yourself if they matter for your jurisdiction. Excel and Google Sheets use different epoch systems, so dates imported between them can be off by decades. Business-day math ignores company-specific shutdowns.
Frequently Asked Questions
How are days between two dates counted?
The tool counts the full days from the start date to the end date. If you want to include the end date itself (e.g. for event countdowns), add one day to the result.
What are business days?
Business days are Monday through Friday, excluding weekends. Public holidays vary by country and are not subtracted — check your local calendar.
How many weeks is 90 days?
90 days is about 12 weeks and 6 days (90 ÷ 7 ≈ 12.86). The result panel breaks any span into weeks and days automatically.
🛒 Recommended for You
As an Amazon Associate, Benditools earns from qualifying purchases.