Measure the span between two dates in years, months, and days, plus total days, weeks, and optional business days. Or add/subtract whole days from a start date.
Calendar difference uses the same year/month/day borrow rules as the age calculator.
Total days are the exact count of midnights between the dates; weeks are derived from that count.
Business days count inclusive weekdays (Monday–Friday) between the earlier and later date.
Add/subtract modes apply whole calendar days, including month and leap-day rollover.
span = normalize(|end − start|); businessDays = countMonFri(inclusive); shift = start ± n days
From 1 January 2024 to 15 March 2025 is 1 year, 2 months, and 14 days (439 total days).
The week of 1–7 January 2024 contains 5 business days if weekends are excluded.
Adding 1 day to 31 January 2024 yields 1 February 2024.
The tool swaps them for the span math and notes that the order was reversed.
No. Only Saturday and Sunday are skipped. Public holidays vary by country.
Yes. February 29 is included when it exists, and day shifts roll correctly across months.
No. Dates stay in your browser for this calculation.
This tool provides calendar estimates only and is not legal advice.
Count Monday–Friday only (inclusive).
Result
Calendar span between the two dates.
| Total days | 439 |
|---|---|
| Weeks | 62 weeks + 5 days |