Percentage Calculator
Calculate percentage of a number, percentage change, what percent one number is of another, and percentage increase or decrease. Instant results with step-by-step formula explanations.
What is X% of Y?
What is X% of Y?
📊
Enter values to see the result instantly
Quick Examples
% of Number
20% of 150
= 30
% Change
80 → 100 (change)
= ▲ 25%
X is what %
50 is what % of 200?
= 25%
% Increase
Increase 200 by 15%
= 230
% Decrease
Decrease 200 by 15%
= 170
% Increase
VAT: 100 increase 20%
= 120
What Is a Percentage?
A percentage is a number or ratio expressed as a fraction of 100. The word "percent" comes from the Latin per centum, meaning "by the hundred." Percentages are used everywhere — from calculating a tip at a restaurant to understanding interest rates, exam scores, discounts, tax rates, and statistical data.
When you say "40%," you mean 40 out of every 100, or the fraction 40/100 = 0.40. This makes percentages a universal, intuitive way to compare proportions across different total sizes.
How to Calculate Percentages
Mode 1 — Percentage of a Number
What is 20% of 150?
Formula
Result = (X / 100) × YExample
(20 / 100) × 150 = 0.20 × 150 = 30Mode 2 — Percentage Change
What is the % change from 80 to 100?
Formula
Change = ((B − A) / A) × 100Example
((100 − 80) / 80) × 100 = (20 / 80) × 100 = 25%Mode 3 — X is What % of Y?
50 is what percent of 200?
Formula
Result = (X / Y) × 100Example
(50 / 200) × 100 = 0.25 × 100 = 25%Mode 4 — Percentage Increase
Increase 200 by 15%
Formula
Result = X × (1 + Y/100)Example
200 × (1 + 15/100) = 200 × 1.15 = 230Mode 5 — Percentage Decrease
Decrease 200 by 15%
Formula
Result = X × (1 − Y/100)Example
200 × (1 − 15/100) = 200 × 0.85 = 170Percentage Increase vs Decrease
Percentage increase and decrease measure how much a value has changed relative to its original amount. They are not interchangeable — a 25% increase followed by a 25% decrease does not return to the original value.
| Type | Formula | Example |
|---|---|---|
| Increase | X × (1 + Y/100) | 200 × 1.15 = 230 |
| Decrease | X × (1 − Y/100) | 200 × 0.85 = 170 |
| % Change | ((B−A)/A) × 100 | 80→100 = +25% |
Real-Life Percentage Examples
Shopping Discounts
A jacket costs $80. It is 30% off. Discount = 30% of 80 = $24. Final price = $56.
Exam Scores
You scored 72 out of 90. 72 is what % of 90? = (72/90) × 100 = 80%.
Investment Returns
Portfolio grew from $5,000 to $6,250. % increase = ((6250−5000)/5000) × 100 = 25%.
Tax Calculation
Product costs $200 before 20% VAT. After tax = 200 × 1.20 = $240.
Salary Raise
Earning $50,000/yr with a 7% raise. New salary = 50,000 × 1.07 = $53,500.
Restaurant Tip
Bill is $65. 18% tip = 18% of 65 = $11.70. Total = $76.70.
Frequently Asked Questions
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