Percentage Calculator

Solve common percentage problems in seconds. This free percentage calculator helps you find percentage of a number, percent change, and percent comparisons for school, finance, shopping, and business calculations.

Percentage Calculator Tools

A collection of tools for your percentage calculation needs.

1. Percentage of a Number
What is% of?
2. X is what percent of Y?
is what percent of?
3. X is Y percent of what?
is% of what?
4. Percentage Increase/Decrease
Fromto?

How to Use the Percentage Calculator

  1. Pick the percentage question type: Choose the calculator card that matches your problem: percentage of a number, what percent, or percent increase/decrease.
  2. Enter your values: Fill in the required inputs for that formula using whole numbers or decimals.
  3. Calculate the result: Click Calculate to instantly see the percentage answer.
  4. Use Clear to run another scenario: Reset a card and test additional values as needed.

Percentage Formula Reference

Percentage of a Number

Result = (Percentage ÷ 100) × Total

What Percent of

Result = (Part ÷ Total) × 100

Find Original Number

Original = Part ÷ (Percentage ÷ 100)

Percent Change

Change % = ((New - Old) ÷ Old) × 100

Frequently Asked Questions

How do I calculate X% of Y?

Multiply Y by X and divide by 100. For example, 20% of 150 is (20 × 150) ÷ 100 = 30.

How do I find what percent one number is of another?

Divide the part by the total, then multiply by 100. Example: 30 is what percent of 150? (30 ÷ 150) × 100 = 20%.

How is percentage increase or decrease calculated?

Use ((new value - original value) ÷ original value) × 100. Positive values indicate increase; negative values indicate decrease.

Can I use decimals in this percentage calculator?

Yes. The calculator accepts decimal inputs and returns formatted percentage results.