How to increase a number by a percentage
✓ Verified in LibreOffice 25.8.7.3 ✓ Verified in Google Sheets (2026-08-30)Add a percentage to a value in one step — a 10% raise, a price plus tax, a target bumped up by 15%.
The formula
| App | Formula | Notes |
|---|---|---|
| Excel (desktop) | =A2*(1+B2) | A2 = the value, B2 = the percent (as 0.1 or a cell formatted 10%). The 1+ keeps the original and adds the increase in one multiply. |
| Google Sheets | =A2*(1+B2) | Identical. For a literal percent: =A2*1.1 adds 10%. |
| LibreOffice Calc | =A2*(1+B2) | Identical. |
How it works
Multiplying by (1 + rate) grows a number by that rate in a single step: 200 × (1 + 0.1) = 220, i.e. the original 200 plus 10% (20). The key is the 1+, which preserves the starting value — A2*B2 alone would give just the 20 increase, not the new total. Enter the rate as a decimal (0.1) or type 10% into the cell, which Excel and Sheets store as 0.1 automatically. To decrease instead, subtract: =A2*(1-B2) takes 10% off. To find what rate turns one number into another, rearrange to =(new-old)/old (see percentage-change). Chaining increases isn't additive — two 10% rises multiply to 1.1×1.1 = 21% total, not 20%.
Verified, not just documented
We ran =A2*(1+B2) in LibreOffice 25.8.7.3 (headless, with forced recalculation) and it returned 220 — exactly the expected result. We then ran the same formulas in Google Sheets, executed 2026-08-30: a formula-only workbook goes into Google Drive, which converts it to a Sheet and recalculates every formula with Google’s own engine, and comes back out as .xlsx carrying the values Google computed. It returned 220 for the worked example, the same value LibreOffice produced. Both engines’ numbers on this page are executed results. The Excel formula follows Microsoft’s official documented syntax — we do not run desktop Excel.