How to calculate a percentage of a number
✓ Verified in LibreOffice 25.8.7.3Find what X% of a number is — like 15% of 80.
The formula
| App | Formula | Notes |
|---|---|---|
| Excel | =A2*B2 | A2=number, B2=percentage entered as 15% (a percent-formatted cell stores 0.15). |
| Google Sheets | =A2*B2 | Identical. |
| LibreOffice Calc | =A2*B2 | Identical. |
How it works
"15% of 80" is just multiplication: 80 × 0.15 = 12. Typing 15% into a percent-formatted cell stores 0.15 under the hood, which is why plain multiplication works. If your percentage is stored as the whole number 15 instead, divide by 100: =A2*B2/100. The reverse question — "12 is what % of 80?" — is =12/80 formatted as a percentage.
Verified, not just documented
We ran =A2*B2 in LibreOffice 25.8.7.3 (headless, with forced recalculation) and it returned 12 — exactly the expected result. Every formula here is confirmed by actually executing it.