Percentage, Margin, Markup & Discount Formula Guide
Percentage calculators can look similar while answering different questions. This guide puts the formulas side by side so you can distinguish percent-of, percentage change, discount, markup, margin, tip and ratio calculations.
Core formulas
| Reference / method | Equivalent / formula | Calculator |
|---|---|---|
| X% of Y | (X ÷ 100) × Y | percentage calculator |
| Percentage change | ((new − old) ÷ old) × 100 | percentage change |
| Sale price after discount | price × (1 − discount% ÷ 100) | discount calculator |
| Markup % | ((selling price − cost) ÷ cost) × 100 | markup calculator |
| Margin % | ((selling price − cost) ÷ selling price) × 100 | margin calculator |
| Tip amount | bill × tip% ÷ 100 | tip calculator |
Margin is not markup
Markup uses cost as the denominator; margin uses selling price as the denominator. If an item costs 60 and sells for 100, the gross difference is 40: margin is 40%, while markup is about 66.67%.
When a formula needs context
Taxes, fees, grading policies, accounting conventions and business rules can change how a real-world figure should be interpreted. Solveberry exposes the arithmetic but does not replace the rules of a specific institution, contract or accounting system.
Reference card: percentage, markup and margin formulas
Use this compact table to keep the denominator straight. Markup is based on cost; margin is based on selling price.
| Calculation | Formula | Quick example |
|---|---|---|
| Markup % | (price − cost) ÷ cost × 100 | 60 → 100 = 66.67% |
| Margin % | (price − cost) ÷ price × 100 | 60 → 100 = 40% |
| Discounted price | price × (1 − discount/100) | 100 at 20% off = 80 |
| Percentage change | (new − old) ÷ old × 100 | 80 → 100 = 25% |
Suggested citation
Solveberry. “Percentage, Margin, Markup & Discount Formula Guide.” Reviewed 20 August 2026. https://solveberry.com/percentage-margin-markup-formulas/
How this guide is maintained
- Purpose
- Explain formulas, definitions and edge cases that materially affect this calculator family.
- Source preference
- Primary standards are used where a published unit definition applies; otherwise Solveberry states the arithmetic method and its limitations directly.
- Last reviewed
- 2026-08-20
Published and maintained by Solveberry. No invented expert credentials are used.