Percentage Formulas in Excel

Percentage of a total in Excel

If B2 contains the part and C2 contains the total, divide the part by the total:

=B2/C2

Format the result cell as Percentage. For 36 out of 240, Excel displays 15%.

Percentage increase formula in Excel

If B2 is the original value and C2 is the new, higher value, use:

=(C2-B2)/B2

For a change from 120 to 150, the formula returns 0.25, displayed as 25% when the cell uses percentage formatting.

Percentage decrease formula in Excel

If B2 is the original value and C2 is the new, lower value, use:

=(B2-C2)/B2

For a drop from 150 to 120, the result is 0.20, or a 20% decrease.

Percentage change formula in Excel

Use one formula when the new value may be higher or lower:

=(C2-B2)/B2

Positive results show growth; negative results show decline. The original value must not be zero because Excel cannot divide by zero.

Common Excel percentage mistakes

• Multiplying by 100 twice: Excel percentage formatting already turns 0.25 into 25%.
• Using the new value as the denominator: percentage change normally compares the difference with the original value.
• Leaving references relative: use an absolute reference such as $B$1 when every row should use the same percentage.

Excel percentage formula FAQs