How to count weeks and days between two dates
✓ Verified in LibreOffice 25.8.7.3Express a date gap as "6 weeks, 3 days" — ages of projects, pregnancies, sprints.
The formula
| App | Formula | Notes |
|---|---|---|
| Excel | =INT((B2-A2)/7)&" weeks, "&MOD(B2-A2,7)&" days" | For a plain decimal week count: =(B2-A2)/7. |
| Google Sheets | =INT((B2-A2)/7)&" weeks, "&MOD(B2-A2,7)&" days" | Identical. |
| LibreOffice Calc | =INT((B2-A2)/7)&" weeks, "&MOD(B2-A2,7)&" days" | Identical. |
How it works
Subtracting dates gives days (46 here, July 24 to September 8); INT of days÷7 gives complete weeks and MOD gives the leftover days — "6 weeks, 4 days". This counts elapsed 7-day blocks from the start date, which is usually what people mean; calendar-week boundaries (how many Mondays passed) are a different question — combine with the first-day-of-the-week recipe for that.
Verified, not just documented
We ran =INT((DATE(2026,9,8)-DATE(2026,7,24))/7)&" weeks, "&MOD(DATE(2026,9,8)-DATE(2026,7,24),7)&" days" in LibreOffice 25.8.7.3 (headless, with forced recalculation) and it returned 6 weeks, 4 days — exactly the expected result. Every formula here is confirmed by actually executing it.