Percentage Formula for Excel & Google Sheets
Copy-paste formulas with plain-English explanations and quick examples.
These work in Excel and Google Sheets. Replace A2/B2 with your cells. Use Format → Number → Percent to display as a percent.
1) What is X% of Y?
=B2*(A2/100)
Meaning: percent × base. Example: 15% of 80 → =80*(15/100) = 12.
2) X is what percent of Y?
=(A2/B2)*100
Meaning: part ÷ whole × 100. Example: 20 of 50 → =(20/50)*100 = 40%.
3) Percentage increase/decrease
=((B2-A2)/A2)*100
Meaning: (new − old) ÷ old × 100. Example: 80 → 92 → =((92-80)/80)*100 = 15%.
4) Add a percentage uplift (markup)
=A2*(1+B2/100)
Example: add 10% to 100 → =100*(1+10/100) = 110.
5) Apply a percentage discount
=A2*(1-B2/100)
Example: 20% off 50 → =50*(1-20/100) = 40.
6) Percent of a column total
=A2/SUM($A$2:$A$100)
Tip: the $ locks the range when you copy down.
FAQs
What’s the basic percentage formula in Excel or Google Sheets?
Use =Part/Total and format as %. For example, =B2/C2 shows B2 as a percent of C2.
How do I calculate percent increase in Excel?
Use =(New−Old)/Old and format as %. Example: =(C2−B2)/B2.
Why do I get 0% when my formula should show a value?
Check that the cell format is Percentage, remove any extra spaces, and make sure you’re not dividing by zero.