Percentage Calculator

The Percentage Calculator is a free, fast, and accurate online tool that helps you calculate all types of percentage values. You don’t need to memorize formulas, switching between multiple sites, or opening a spreadsheet just to find percentages. Percentage calculator does it all on one page.

Using this tool, you can calculate:

lPercentage of a number

lWhat percent one number is of another

lPercentage increase

lPercentage decrease

lPercentage difference (comparison)

lReverse percentage (find the original total when the percentage result is known)

Each calculator is simple: enter values → click Calculate → get the result instantly.

Why Use the Percentage Calculator?

Many websites offer only one calculator (“X% of Y”), but real-world percentage problems involve more than one type of calculation.

This tool offers five calculations:

1. Basic Percentage Calculator - Find X% of a Number

This calculator answers the simplest and most common percentage question:

What is X% of Y?

Example: What is 25% of 300?

How to use Percentage Calculator?

1.        Enter the percent (%) in the input box.

2.        Enter the total in the next input box.

3.        Click Calculate to find Part Value.

Formula

Percentage Value = (Percent × Total) ÷ 100

Example Calculation

Percent (%) = 25%, Total = 300, Result = ?

(25 × 300) ÷ 100 = 75

When is Basic Percent used?

lCalculating discount amount (e.g., 40% off).

lCalculating tax or VAT.

lCalculating marks in percentage.

2. Find the Percent (%) - Find What Percent One Number Is of Another

This percentage calculator finds:

X is what percent of Y?

Example:

45 is what percent of 90?

How to Find the Percent %?

1.        Enter the part value (X).

2.        Enter the total value (Y).

3.        Click the Calculate button to find the Percent %.

Formula

Percent (%) = (Part ÷ Total) × 100

Example

Part (X) = 45, Total (Y) = 90, Percent = ?

(45 ÷ 90) × 100 = 50%

Real-world use cases

lWhat percent of your income goes toward rent?

lWhat percent of total marks a student scored?

lWhat percent of company budget is allocated to marketing?

3. Reverse Percentage - Find the Original Total (If X% = Y)

This tool is used when you already know the percentage result, but need to find the original total.

Example: 45 is 15% of what number?

How to Find the Original Total?

1.        Enter the part value (X).

2.        Enter percentage (P).

3.        Hit the Calculate button to get the original total.

Formula

Total = (Part ÷ Percent) × 100

Example

Percent % = 15%, Part Value (X) = 45, Original Total = ?

(45 ÷ 15) × 100 = 300%

Why finding original total is important?

lFinding original price before discount.

lReversing profit or loss calculations.

lReverse engineering marked price plus tax.

4.    Percentage Increase Calculator - How Much Did Something Grow?

Percentage increase calculator calculates how much something has increased, in percentage.

Example: Price increased from 500 to 650.

How to Find the Percent Increase?

1.        Enter the old value in the input box.

2.        Enter the new value in the next input box.

3.        Select Action from the list → Increase (+).

4.        Click Calculate to get the percent increase.

Formula

% Increase = ((New − Old) ÷ Old) × 100

Example

Old Value = 500

New Value = 650

% Increase = ?

((650 − 500) ÷ 500) × 100 = 30%

Practical use cases of percent increase:

l Salary increase (from 50,000 to 60,000).

l Product price inflation.

l Increase in number of followers/subscribers.

5.    Percentage Decrease Calculator - How Much Did Something Drop?

This percentage calculator calculates how much something has decreased, in percentage.

Example: You reduced monthly spending from 700 to 500. Now lets find the percentage decrease.

How to Find the Percent Decrease?

1.        Enter the old value.

2.        Enter the new value.

3.        Select Action from the list → Decrease (-).

4.        Click Calculate to get the percent decrease.

Formula

% Decrease = ((Old − New) ÷ Old) × 100

Example

Old Value = 700, New Value = 500, % Decrease = ?

((700 − 500) ÷ 700) × 100 = 28.57%

Common scenarios of percent decrease:

lPrice reduction during sale.

lWeight reduction progress.

lReduced electricity or fuel usage.

6. Percentage Difference Calculator - Compare Two Values

This tool compares two values and finds the difference in percentage.

Example: Compare values 80 and 100.

How to Find the Percent Difference?

1.        Enter the Value 1 (V1).

2.        Enter Value 2 (V2).

3.        Hit the Calculate button to find the percent difference.

Formula

% Difference = (|A − B| ÷ ((A + B) ÷ 2)) × 100

Example

Value A = 80

Value B = 100

Difference = ?

(|80 − 100| ÷ ((80 + 100) ÷ 2)) × 100

(|-20| ÷ 90) × 100 = 100

(20 ÷ 90) × 100 = 22.22%

Note: The absolute value sign “| |” converts the negative into positive.

Use cases of percent difference

l Compare exam scores.

l Compare product prices.