Percentage Formula in Google Sheets
The core idea is part ÷ whole, then format the cell as a percentage. Here are the common cases.
=A2/B2
Part divided by whole. Then format the cell as Percent (Format ▸ Number ▸ Percent) so 0.25 shows as 25%.
How it works
A percentage is a ratio: divide the part by the whole and Sheets stores it as a decimal (0.25). Applying Percent formatting multiplies the display by 100 and adds the % sign — the underlying value stays 0.25, so further maths still works.
Variations
Percentage change (new vs old)
=(B2-A2)/A2
Positive = increase, negative = decrease. Format as percent.
Percent of a grand total
=B2/SUM(B$2:B$100)
$ locks the total range so it stays fixed when you drag down.
Add a percentage
=A2*(1+20%)
Adds 20% to A2.
What number is X% of Y
=20%*A2
20% of A2.
Examples
| Scenario | Formula |
|---|---|
| Score as a percentage | =Correct/Total |
| Month-over-month growth | =(ThisMonth-LastMonth)/LastMonth |
FAQ
Why does my percentage show as 2500% instead of 25%?
The value is already a percentage but you divided again, or you applied Percent formatting to a value that was already 25. Divide part by whole once, then format.
How do I show a percentage with no decimals?
Select the cells and click the decrease-decimals button, or Format ▸ Number ▸ Custom number format ▸ 0%.
Related formulas
- Google Sheets Regex Tester — REGEXEXTRACT, REGEXMATCH & REGEXREPLACE (RE2)
- Google Sheets QUERY Builder — Generate the QUERY Formula & Copy
- Google Sheets IF Formula Builder — Nested IF & IFS Generator
- Google Sheets Percentage Calculator — % Change, % of Total, Increase/Decrease Formulas
- Google Sheets Date Difference Calculator — Days, Months, Years Between Dates
- Google Sheets XLOOKUP / VLOOKUP Builder — Generate the Lookup Formula & Copy
- "Array Result Was Not Expanded" in Google Sheets — How to Fix It
- "Did Not Find Value in VLOOKUP Evaluation" — How to Fix It