MathUpdated May 2026

Percentage Calculator

Solve any percentage problem: percent of a number, percent change, increase, decrease, and percentage points.

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Updated 2026

Percentage Calculator

Use this free percentage calculator for percent, percent change, discount, or tip calculations.
About Percentage Calculations

Percentages are a way to express a number as a fraction of 100.

Common Applications:

  • Basic Percentage: Find X% of a number
  • Percentage Change: Increase or decrease by X%
  • Discounts: Calculate sale prices and savings
  • Tips: Calculate restaurant tips and service charges

Quick Tips:

  • 10%: Move decimal one place left
  • 20%: Double 10% value
  • 25%: Divide by 4
  • 50%: Divide by 2
  • 100%: The entire amount

Common Tip Rates:

  • 15%: Standard service
  • 18%: Good service
  • 20%: Excellent service
  • 25%+: Outstanding service

Remember that percentages are always calculated relative to the original amount unless specified otherwise.

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How our percentage calculator works

1

Choose your problem type

Select from percent of a number, percent increase, percent decrease, percentage points, or tip calculation. Each mode is tuned for the most common use case.

2

Enter the numbers

Type the values relevant to your problem. The calculator auto-detects the right formula and shows the math step by step.

3

Get the result with explanation

See the final answer plus the formula and the steps used. Useful for checking your own work or learning the underlying math.

Key things to know about our percentage calculator:

  • Percent change formula: ((new - old) / old) x 100. Going from 50 to 60 is a 20% increase, but 60 to 50 is a 16.67% decrease.
  • Percentage points: The arithmetic difference between two percentages. 5% to 7% is a 2 percentage point increase but a 40% relative increase.
  • Everyday use: Use the percentage calculator for tips, discounts, taxes, grades, statistics, and any other percent problem.

For related calculations, try our tip calculator.

Verified accuracy

Cross-checked against authoritative formulas (IRS, NIST, ACM) and updated for 2025/2026 tax years and rates.

Instant results

No server roundtrip. All math runs in your browser so results appear the moment you finish typing.

Your data stays private

We never collect, store, or transmit your inputs. Every calculation runs locally in your browser.

Learn as you calculate

Each calculator includes the formula, plain-English explanation, and FAQs so you understand the result.

Estimates only. Calculator results are for educational and planning purposes — not professional advice. For binding decisions on taxes, investments, health, or legal matters, consult a qualified professional.

FAQ

Frequently asked questions

Everything you need to know about this calculator. Can't find what you're looking for? Email our team.

20% of $80 is $16. The formula: 80 x 0.20 = 16. Our percentage calculator does this in one click. The percentage calculator also handles reverse percentages (e.g. 16 is 20% of what number, answer: 80) and percentage change (e.g. 80 to 96 is a 20% increase).

How it works

How to calculate percentages, discounts, and tips

Use the percentage calculator to find any percentage, percent change, discount, or tip in three steps.

  1. 1

    Choose a calculation mode

    Select what you want to compute: basic percentage, percent change, percent off (discount), or tip. Each mode has its own input fields.

  2. 2

    Enter your values

    Fill in the two numbers the calculation needs. For a discount, that is the original price and the discount percent. For a tip, that is the bill amount and tip percent.

  3. 3

    Read the result

    The result appears immediately below the inputs, showing the computed value and a short explanation of what the numbers mean.

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