Calculators & Converters★ Free forever✓ No account🔒 No upload📴 Works offlineUpdated April 28, 2026

Free Percentage Calculator Online — No Signup Required

Percentage Calculator helps you Solve common percentage calculations instantly — what is X% of Y, percentage change, and reverse percent — free, in 2026, without leaving the browser. It is built for operators, students, analysts, and decision makers, so you can run quick calculations without installing spreadsheet templates or apps with a fast public URL, clear output, and a workflow that stays focused on the task instead of setup.

Browse all toolsBrowse more calculators & converters toolsBuilt by Achraf A., Full-Stack Developer · Morocco

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What is Percentage Calculator?

A percentage calculator solves the most common percentage problems instantly: What is X% of Y? X is what percent of Y? What is the percentage change from X to Y? What is the original value if X is P% of it? These calculations appear constantly in daily and professional life — discounts, tax calculations, commission rates, grade scoring, survey data analysis, financial returns, and statistical reporting all require percentage arithmetic.

This calculator handles four distinct percentage operations: (1) Percentage of a value (15% of 200 = 30), (2) What percent is X of Y (30 is what % of 200 = 15%), (3) Percentage change between two values ((new - old) / old × 100 — used for growth rates and price changes), and (4) Reverse percentage (if 30 is 15% of the whole, what is the whole = 200). Select the calculation type, enter the values, and get the result with the formula shown.

How to use Percentage Calculator in 3 steps
  1. 1

    Select calculation type

    Choose from: % of a value, what % is X of Y, % change between values, or reverse percentage.

  2. 2

    Enter your values

    Fill in the known values. The calculator shows which fields are required for each calculation type.

  3. 3

    Copy the result

    The answer appears instantly with the formula used.

Key features and benefits
  • Four calculation types covering all common percentage problems
  • Shows the formula alongside the result
  • Handles negative percentages and decreases
  • Free, no account, instant calculation
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References and standards

Percentage Calculator FAQs

Quick answers about the workflow, privacy, and where this tool fits in a broader job.

How do I calculate a discount percentage?

Use the 'percentage change' mode: enter the original price as the start value and the sale price as the end value. The result is the negative percentage change — a discount of -20% means a 20% price reduction.

What is the formula for percentage change?

Percentage change = ((New Value - Old Value) / Old Value) × 100. A positive result is an increase; negative is a decrease. For example, sales rising from 100 to 125 is a 25% increase: ((125-100)/100) × 100 = 25%.

How do I add a percentage to a number (like adding tax)?

Multiply the base value by (1 + percentage/100). For 20% tax on $100: 100 × 1.20 = $120. For a 15% tip on a $50 meal: 50 × 1.15 = $57.50.

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Built and maintained by

Achraf A.

Founder & developer — built and maintains every tool on this site

Last updated:

Tested in Chrome, Firefox, and Safari on desktop and mobile.

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