Logic Engine

PERCENTAGE CALCULATOR

6 modes: ratio, value, change, difference, margin, tip. History saved. No sign-up.

Private by design No signup · Free

Percentage Calculator

Enter values to calculate

Formula

Select a mode and enter values

History

Frequently Asked Questions

How does the Percentage Calculator work?

Enter part and whole, or old and new values. The tool computes share (part ÷ whole × 100), percent change and discount vs markup locally, with student-marks and margin examples for 2026 workflows.

Is the Percentage Calculator free to use?

Yes, it is completely free with no hidden fees, subscriptions, or usage limits. No sign-up or account required. With Percentage Calculator, re-run with your own inputs before deciding.

How accurate are the results?

Percentages use exact part-over-whole and change formulas rounded to 2 decimals. Verify whether discount applies pre- or post-tax in your invoice flow, since order changes totals.

Is my data safe when using Percentage Calculator?

Absolutely. All calculations happen locally in your browser. Your data never touches any server and is never stored or tracked. With Percentage Calculator, re-run with your own inputs before deciding.

What percentage calculations are supported?

Six modes: what percent X is of Y, X% of Y, percentage change from old to new, percentage difference between two numbers, margin vs markup, and tip calculator.

How does the percentage change calculator work?

Enter the old value and the new value. The tool calculates the percentage increase or decrease using the formula: (new - old) / old × 100.

What is the difference between margin and markup?

Margin is profit as a percentage of the selling price. Markup is profit as a percentage of the cost price. Margin = (Price - Cost) / Price × 100. Markup = (Price - Cost) / Cost × 100.

Is my calculation history saved?

Yes, every calculation is saved in your browser's local storage. Click any history entry to restore it, or clear the history at any time.

How to Use

Select a Mode

Choose from 6 calculation modes: Ratio, Value, Change, Difference, Margin, or Tip using the mode selector.

Enter Values

Fill in the input fields for your selected mode. Results update instantly as you type.

Copy or Save

Click the result to copy it to your clipboard, or let it auto-save to your calculation history.

How to Calculate

The Percentage Calculator uses transparent calculation logic to compute results based on your inputs. Enter your values, select Compute, and the tool processes everything instantly using optimized algorithms — all within your browser.

About the Percentage Calculator

The Percentage Calculator is a versatile online tool that handles 6 different percentage calculation modes: ratio finding (X is what % of Y), value finding (X% of Y), percentage change, percentage difference, margin vs markup, and tip calculation.

All calculations are performed locally in your browser. No data is sent to any server, no sign-up required, and your calculation history is saved in local storage for reference between visits.

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Methodology & feedback

Figures run locally in your browser from the values you enter (page updated 2026-10-02). Estimates are educational only — verify finance, tax and health decisions with a qualified professional (see Disclaimer). Spotted an error? Report it via contact and we correct with a new update date.

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