% Percentage Calculator

Calculate percentages instantly — find a percent of a number, percentage change, or increase/decrease.

About Percentage Calculator

This free percentage calculator handles three common percentage scenarios in one tool. Find what a certain percentage of a number equals, calculate the percentage change between two values, or increase/decrease a number by a given percentage. Every result includes the step-by-step formula so you can learn how it works.

Three Calculation Modes

Switch between "% of Number," "% Change," and "Increase/Decrease" to handle any percentage math you need.

Instant Results

Get your answer immediately as you type with a single click — no page reload or waiting.

Formula Shown

Each result includes the exact formula used, helping you understand the math behind the calculation.

Free & Unlimited

Use as many times as you need. No account, no sign-up, no tracking — just pure calculation.

📋 Common Use Cases

Shopping & Discounts

Calculate sale prices, percentage discounts, and tip amounts instantly. Know exactly what you will pay before reaching the register.

Cooking & Recipe Scaling

Adjust recipe ingredient quantities using ratios and proportions. Scale recipes up for parties or down for smaller meals with perfect accuracy.

Academic Homework Help

Students can check their work and understand step-by-step solutions for fractions, percentages, and ratio problems across math and science courses.

Quick Business Math

Calculate markups, discounts, and proportional adjustments. Make fast, accurate pricing decisions without reaching for a physical calculator.

🪜 How to Use This Tool

  1. Enter your numbers
    Type the values you want to calculate. Most calculators accept whole numbers, decimals, and fractions in standard notation.
  2. Select the operation or mode
    Choose what you want to compute — percentage of a number, fraction arithmetic, or ratio simplification — depending on the calculator.
  3. See the result with explanation
    The answer appears instantly. Most math calculators show step-by-step work so you understand how the result was derived.
  4. Copy or reuse the result
    Click to copy the answer for use in homework, shopping decisions, or business calculations.

📚 Related Guides

Frequently Asked Questions

Are these calculators really free?▼
Yes. All calculators on iluv.tools are completely free. No signup, no account, no credit card required. Every calculation runs instantly in your browser.
Is my data sent anywhere?▼
Absolutely not. All calculators are pure client-side JavaScript. Your numbers, dates, and inputs never leave your browser. No server processing, no tracking.
How accurate are these calculators?▼
Calculators use standard mathematical formulas with double-precision floating point. Results match industry-standard financial and scientific calculations.
Can I use calculators on mobile?▼
Yes. All calculators work on mobile browsers (iOS Safari, Android Chrome) with responsive layouts.