Percentage Calculator

Quickly compute what percent A is of B, X% of Y, and percentage change between two numbers. Calculate percentages, percent-of values, and percentage change.

Introduction

Percentage Calculator is a free, browser-based utility in our Math Tools collection. Quickly compute what percent A is of B, X% of Y, and percentage change between two numbers. Percentage Calculator handles common percent math for finance, grades, and analytics in the browser. Everything runs locally in your browser — inputs stay on your device, with no account or upload required. Highlights include a of b.

Features

A of B
X% of Y
Change %

How to use

1
Enter values in any section.
2
Copy the summary.

Example

Discount

Input

15% of 80

Output

Benefits

Run Percent Calc entirely in the browser with no signup or installation.
Keep sensitive sample data private — processing never leaves your device.
A of B
X% of Y
Change %
Pair it with Units and Random Number when your workflow needs adjacent utilities.

FAQs

Results show useful precision without noisy trailing zeros.

No.

Supported for change calculations.

Yes. Percent Calc on EverydayDevTools is free, with no account, watermarks, or usage caps for normal interactive use.

No. Percent Calc runs in your browser. Your input is processed locally and is not sent to EverydayDevTools servers.

Quickly compute what percent A is of B, X% of Y, and percentage change between two numbers. It fits everyday math tools tasks when you want a fast local utility instead of installing a CLI or opening a heavy IDE feature.

Core capabilities include: A of B; X% of Y; Change %.

Developers often pair Percent Calc with Units, Random Number, Base Converter. Open Related tools on this page for quick links.