Multiply Y by X and divide by 100. For example, 15% of 200 = 200 × 15 ÷ 100 = 30.

How do I find what percent X is of Y?

Divide X by Y, then multiply by 100. For example, 30 out of 200 = (30 ÷ 200) × 100 = 15%.

How is percentage change calculated?

Subtract the old value from the new value, divide by the old value, then multiply by 100. A positive result is an increase; a negative result is a decrease.

What is the difference between percentage and percentage points?

A percentage expresses a fraction of a whole (e.g. 40%). A percentage point is the arithmetic difference between two percentages — going from 30% to 40% is a 10 percentage-point increase but a 33.3% relative increase.

Can I calculate a negative percentage change?

Yes. If the new value is smaller than the old value the result will be negative, indicating a decrease. For example, going from 80 to 60 is a −25% change.

Percentage Calculator

Name: Percentage Calculator
Availability: InStock
Author: Nham Vu

Instantly calculate what X% of a number is, find what percent one number is of another, or compute percentage change between two values.

What is X% of Y?

Percentage (X)

Number (Y)

Enter values on the left to see the result

X% of Y

Result = Y × X ÷ 100

X of Y %

Result = (X ÷ Y) × 100

% Change

Result = ((New − Old) ÷ Old) × 100

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Summary

Instantly calculate what X% of a number is, find what percent one number is of another, or compute percentage change between two values.

How it works

Choose one of the three calculation modes using the tab buttons.
Enter the required numbers into the input fields.
The result updates instantly as you type.
Click "Copy Result" to copy the answer to your clipboard.
Use the Reset button to clear all fields and start a new calculation.

Use cases

Find a discount amount — e.g. 20% off a $149 item.
Calculate a tip at a restaurant.
Determine what share of a total budget one category takes.
Track sales growth or decline month-over-month.
Convert a test score (e.g. 18 out of 24) to a percentage.
Compute a commission on a sale.
Check VAT or tax amounts on an invoice.
Measure weight-loss or gain as a percentage of starting weight.

Frequently Asked Questions

Last updated: 2026-06-09 · Reviewed by Nham Vu