Percentage Calculator - Calculate Percentages Online Free

Free percentage calculator to find percentages instantly. Calculate percentage of a number, percentage change, increase, decrease and more.

Percentage Calculator

What do you want to calculate?
Quick Reference
10% of 100 = 10
25% of 80 = 20
50 is 25% of 200
100 → 150 = +50%

Percentage Formulas

Find X% of Y
Result = (X / 100) × Y
X is what % of Y?
Percentage = (X / Y) × 100
Percentage Change
Change = ((New - Old) / Old) × 100
Increase by X%
Result = Number × (1 + X/100)
Decrease by X%
Result = Number × (1 - X/100)

Frequently Asked Questions

How do I calculate percentage of a number?

To find X% of Y, multiply Y by X and divide by 100. For example, 25% of 200 = (200 × 25) / 100 = 50. Our calculator does this instantly for you.

How do I find what percentage one number is of another?

To find what percentage X is of Y, divide X by Y and multiply by 100. For example, 50 is what % of 200? (50 / 200) × 100 = 25%.

How do I calculate percentage increase or decrease?

Percentage change = ((New Value - Old Value) / Old Value) × 100. If the result is positive, it's an increase; if negative, it's a decrease.

How do I add a percentage to a number?

To increase a number by X%, multiply the number by (1 + X/100). For example, 100 increased by 20% = 100 × 1.20 = 120.

How do I subtract a percentage from a number?

To decrease a number by X%, multiply the number by (1 - X/100). For example, 100 decreased by 20% = 100 × 0.80 = 80.

What is the formula for percentage?

The basic percentage formula is: Percentage = (Part / Whole) × 100. This can be rearranged to find Part = (Percentage × Whole) / 100 or Whole = (Part × 100) / Percentage.