Percentage Calculator
Calculate percentages, find percentage changes, and distribute percentages
Basic Percentage
Percentage of a Value
Percentage Change
Percentage Distribution
What is the Percentage Calculator?
Percentages come up constantly, exam scores, discounts, tax rates, tip amounts, interest calculations. A percentage calculator removes the mental gymnastics. It handles three common types of questions: 'What is X% of Y?', 'X is what percent of Y?', and 'What is the percentage change between two values?' CalciHub's tool covers all three in a single page, so you don't need separate tools for each scenario.
How Does It Work?
Each question type uses its own formula:
What is X% of Y? Result = (X / 100) × Y
X is what % of Y? Result = (X / Y) × 100
Percentage change: Result = ((New − Old) / Old) × 100
X = the percentage or partial value
Y = the base or whole value
Old = original value (for change calculations)
New = updated value (for change calculations)
How to Use CalciHub's Percentage Calculator
1. Select which type of percentage question you want to answer.
2. Enter the required numbers in the fields that appear.
3. Click Calculate to see the result.
4. Use the Clear button to reset and try a different scenario.
5. Switch between question types without reloading the page.
Tip: For percentage change, make sure you enter the original value first and the new value second, reversing them gives a different (and incorrect) result.
A Quick Example
A product originally costs 80. It is now on sale for 68. What is the discount percentage?
Formula: ((Old − New) / Old) × 100
= ((80 − 68) / 80) × 100
= (12 / 80) × 100
= 15%
The item is discounted by 15%. Knowing this helps compare deals across different products, where the raw price drop alone can be misleading.
Frequently Asked Questions
Use the percentage change formula: ((New − Old) / Old) × 100. If the result is positive, it is an increase. If it is negative, it is a decrease. CalciHub labels this clearly in the output.
Percentage points measure an absolute difference between two percentages. For example, going from 20% to 25% is a 5 percentage point increase but a 25% relative increase. These are not the same thing, and mixing them up is a common source of confusion.
Yes. To find the tax on a price, use 'What is X% of Y?' — enter the tax rate as X and the pre-tax price as Y. The result is the tax amount. Add it to the original price to get the final total.
Divide the final price by (1 + rate/100). For example, if a price of 115 includes 15% tax, the original is 115 / 1.15 = 100. This is reverse-percentage logic, and it works for any added percentage.
Yes, fully free. No login, no limits — just enter your numbers and get an instant result.
Related Mathematics calculators
See all Mathematics →- Scientific CalculatorAdvanced calculator with trigonometry, logarithms, and constants.
- Random Number GeneratorGenerate random numbers, integers, or sequences within any range.
- Area CalculatorCalculate areas of circles, rectangles, triangles, and more.
- Algebra CalculatorSolve linear equations ax+b=c or 2×2 systems of equations.
- Quadratic Equation SolverSolve ax²+bx+c=0, find roots, discriminant, and vertex.
- Fraction CalculatorAdd, subtract, multiply, and divide fractions with step-by-step results.
Guides on this topic
View all posts →Longer reads that explain the method behind the numbers.