100% Free Online Web Tool

Percentage Calculator

Calculate percentages

Math Calculator

Percentage Calculator

Calculate percentages, increase, decrease and percentage change with 5 different operations.

Key Features & Highlights

Multiple Calculation Types

Calculate percentage of number, percentage increase/decrease, percent change, and what percent X is of Y.

Instant Results

See results immediately as you type - no need to click calculate button.

Reverse Percentage

Find original value from percentage - useful for discounts, taxes, and markups.

Percentage Change

Calculate percentage increase or decrease between two values with sign indication.

Step-by-Step Formula

See the exact formula used so you can verify and learn how percentages work.

Mobile Optimized

Perfect for quick calculations on the go - works flawlessly on any device.

How to Use Percentage Calculator

1

Choose Calculation Type

Select what you want: % of a number, % increase/decrease, or what % X is of Y.

2

Enter Your Values

Input the two numbers required for your selected calculation type.

3

See Instant Result

The percentage result appears automatically with the exact calculation shown.

4

Copy or Verify

Copy the result to clipboard or check the formula used to verify accuracy.

Frequently Asked Questions

How do I calculate percentage of a number?

Percentage of X = (percent/100) × X. For example, 25% of 200 = (25/100) × 200 = 50. Our calculator does this instantly for any values.

How to calculate percentage increase?

% Increase = ((New - Old) / Old) × 100. If price went from 100 to 150, increase is ((150-100)/100) × 100 = 50%.

What is percentage change?

Percentage change measures relative difference between two values. Positive means increase, negative means decrease. Very useful for comparing values over time.

How do I find what percent A is of B?

Formula: (A/B) × 100. Example: What percent is 25 of 200? (25/200) × 100 = 12.5%.

Can I calculate discount percentages?

Yes! Use percentage decrease. Original: 500, Sale: 400. Discount = ((500-400)/500) × 100 = 20% off.

How to calculate tip percentage?

For 15% tip on $50: (15/100) × 50 = $7.50. Or use our dedicated Tip Calculator for more options including bill splitting.