What is the basic percentage formula in Excel?

Use =part/total, then format the result as Percentage.

How do I calculate percentage increase in Excel?

Use =(new value - old value) / old value, then apply percentage formatting.

Why is my Excel percentage 2500% instead of 25%?

You probably multiplied by 100 and also applied percentage formatting. Use the decimal result and format as Percentage.

How do I calculate percentage of total by row?

Divide each row value by the grand total and lock the total cell with an absolute reference.

Formulas - 2026-05-12

Excel Percentage Formula: Complete Guide

Learn how to calculate percentages in Excel, including percent of total, percentage increase, percentage decrease, discounts, margins, and completion rates.

How Percentages Work in Excel

Excel stores percentages as decimal values. For example, 25% is stored as 0.25. When you apply percentage formatting, Excel displays the value as a percentage. Basic percentage formula: \\\ =part/total \\\ Then format the result as Percentage.

Percent of Total

If sales are in B2 and total sales are in B10: \\\ =B2/$B$10 \\\ Use an absolute reference for the total so the denominator stays fixed when copied down.

Percentage Increase

To calculate growth from old value to new value: \\\ =(NewValue-OldValue)/OldValue \\\ Example: \\\ =(C2-B2)/B2 \\\ Format the result as Percentage.

Percentage Decrease

The formula is the same: \\\ =(NewValue-OldValue)/OldValue \\\ If the new value is lower, the result will be negative.

Discount Formula

To calculate the final price after a discount: \\\ =Price*(1-Discount) \\\ Example: \\\ =A2*(1-B2) \\\ If A2 is 100 and B2 is 20%, the result is 80.

Profit Margin

Profit margin shows profit as a percentage of revenue: \\\ =(Revenue-Cost)/Revenue \\\ Example: \\\ =(B2-C2)/B2 \\\

Related Guides

Absolute Reference in Excel SUM function AVERAGE function ROUND function

Percentage Formula Table

Need Formula Percent of total =Part/Total Percent increase =(New-Old)/Old Percent decrease =(New-Old)/Old Discounted price =Price*(1-Discount) Profit margin =(Revenue-Cost)/Revenue Completion rate =Completed/Total

Expert Formatting Advice

Do not multiply by 100 if the cell is formatted as Percentage. Excel stores 25% as 0.25, and percentage formatting handles the display. Use absolute references for fixed totals: \\\ =B2/$B$10 \\\ This keeps the total fixed when the formula is copied down.

Related Guides

Review Absolute Reference in Excel, SUM, AVERAGE, and ROUND for clean percentage reports.

Percent vs percentage points

A rise from 10% to 15% is a 5 percentage point increase but a 50% relative increase. Label reports clearly to avoid executive misreads. Pivot shortcut: Value Field Settings → Show Values As → % of Grand Total.

Frequently asked questions

What is the basic percentage formula in Excel? Use =part/total, then format the result as Percentage.
How do I calculate percentage increase in Excel? Use =(new value - old value) / old value, then apply percentage formatting.
Why is my Excel percentage 2500% instead of 25%? You probably multiplied by 100 and also applied percentage formatting. Use the decimal result and format as Percentage.
How do I calculate percentage of total by row? Divide each row value by the grand total and lock the total cell with an absolute reference.