Percentage Calculator
Calculate percentages, increases, decreases, discounts, and margins instantly.
Calculate Percentage of Value (What is X% of Y?)
Percentage Change / Difference (From A to B)
Discount & Sale Price Calculator
Overview
Free online percentage calculator. Solve what is X% of Y, calculate percentage change from initial to final value, compute sales discounts, and markup prices with detailed formulas.
Percentage Calculation: Increases, Decreases & Discounts
The Percentage Calculator handles all standard mathematical percent operations: finding X% of Y, calculating percentage changes between two milestones, determining sales discounts, and gross margin markups.
Whether verifying commercial invoices or evaluating investment returns, the calculator displays transparent mathematical formulas for complete auditability.
Basic formula: `(Value × Percentage) / 100`. Percentage difference formula: `((New - Old) / Old) × 100`.
How to Compute Percentages
Fast & IntuitiveSelect Calculation Mode
Pick "X% of Y", "Percentage Increase/Decrease", or "Sales Discount".
Type Initial Figures
Input your initial values and target percentage rates.
Review Breakdown
View the instant calculation along with step-by-step arithmetic proof.
Formula & Calculation Details
Practical Examples
Key Highlights & Advantages
Zero server uploads. Everything processes securely within your local browser memory.
Immediate results with no file upload or download queues.
No registration, no paywalls, and no hidden quotas.
Seamlessly optimized for mobile smartphones, tablets, and desktop workstations.
All data processing runs natively via W3C compliant browser hardware acceleration.
- To quickly calculate 15% tip mentally, find 10% (move decimal one spot left) and add half of that amount.
Related Guides
Frequently Asked Questions
1 Q&AsHow do I calculate what percentage one number is of another?
Divide the part by the whole and multiply by 100: (Part / Whole) × 100.