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Percentage Calculator

Find X% of Y, calculate percent change, add tips and discounts — four calculators in one.

What is X% of Y?

% of
Result:50

X is what % of Y?

is what % of
Result:12.5%

Percentage Change

Fromto
Change:+25%

Add / Subtract Percentage

±%
Add:180
Subtract:120

Quick Reference

10% of 500
50
15% tip on $85
$97.75
20% discount off $120
$96
7.5% sales tax on $200
$215

About this tool

A four-in-one percentage calculator covering the most common everyday math: finding a percentage of a number, expressing one number as a percentage of another, calculating percent increase or decrease, and adding or subtracting a percentage from a value.

🔢X% of Y — find the part
📊X is what % of Y — find the rate
📈Percent change — increase or decrease
➕Add or subtract a percentage
⚡All results update instantly
📋Copy any result with one click

How to use it

Quick steps to get the most out of this utility.

  1. 1

    Choose a calculation type

    Pick from four common percentage problems shown side by side.

  2. 2

    Enter your values

    Type numbers into the input fields — results appear instantly.

  3. 3

    Copy the result

    Click the copy icon next to any result to use it elsewhere.

Common percentage calculations

  • Restaurant tips: 15%, 18%, or 20% of the bill
  • Retail discounts: 25% off the original price
  • Sales tax: add 6–10% to the pre-tax amount
  • Investment returns: percent change from purchase to current price
  • Grade calculation: score as a percentage of total points

Frequently asked questions

How do I calculate X% of Y?+

Multiply Y by X and divide by 100. For example, 20% of 150 = (150 × 20) ÷ 100 = 30. In the tool, enter 20 in the percentage field and 150 in the total field.

How do I find what percentage X is of Y?+

Divide X by Y and multiply by 100. For example, 30 is what percent of 150? (30 ÷ 150) × 100 = 20%. Use the second calculator on this page.

How do I calculate percentage change?+

Percentage change = ((New Value - Old Value) / |Old Value|) × 100. A positive result is an increase; negative is a decrease. The tool labels these as percent change from one value to another.

How do I add a percentage to a number?+

Multiply the number by (1 + percentage/100). For example, adding 15% to $100 = $100 × 1.15 = $115. To subtract 15%, multiply by 0.85.

How is sales tax calculated?+

Multiply the pre-tax price by (1 + tax rate/100). A $50 item with 8.5% sales tax = $50 × 1.085 = $54.25.

Keep exploring

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