Free Percentage Calculator Online

Five percentage calculators in one. Instant results as you type.

What is X% of Y?
What is%of= --
X is what percent of Y?
is what % of= --%
Percentage change from X to Y
Fromto= --%
Add a percentage to X
+% = --
Subtract a percentage from X
-% = --

Key Features

Everything you need in one free tool

5 Calculator Modes

Covers all common percentage calculations: percent of, what percent, change, add, and subtract.

Instant Results

Results update in real time as you type. No button press required.

Works Everywhere

Runs entirely in your browser with no downloads or accounts needed.

About This Tool

A comprehensive percentage calculator covering five common calculation types. All results are computed instantly in your browser.

Frequently Asked Questions

How do I calculate what percent X is of Y?

Divide X by Y and multiply by 100. For example, 25 out of 200 is (25/200)*100 = 12.5%.

Use the second calculator section to get this result instantly.

Make sure Y is not zero to avoid division errors.

How do I calculate percentage change?

Subtract the old value from the new value, divide by the absolute value of the old value, and multiply by 100.

A positive result means an increase, a negative result means a decrease.

Use the third calculator section to compute this instantly.

How do I add a percentage to a number?

Multiply the number by (1 + percentage/100). For example, 200 + 15% = 200 * 1.15 = 230.

This is useful for calculating prices with tax or tips.

Use the fourth calculator section for this.

How do I subtract a percentage from a number?

Multiply the number by (1 - percentage/100). For example, 200 - 10% = 200 * 0.90 = 180.

This is useful for calculating discounts and sale prices.

Use the fifth calculator section for this.