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Overview

Percentage Calculator

Solve the three most common percentage questions: find a percentage of a value, find what percent one number is of another, and calculate percent change.

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Percentage Calculator

Solve the three most common percentage questions instantly.

e.g. 15% of 200 = 30

Enter values above to calculate

What you can solve

How do I find what percent of a number is?

Select 'What is X% of Y?' mode, enter the percentage and the total. The calculator multiplies (percentage ÷ 100) × total. For example, 15% of 60 is 9. This is useful for calculating tips, discounts, or tax.

How do I calculate percent increase or decrease?

Use the '% change' mode. Enter the original value and the new value. Percent change = ((new − original) ÷ original) × 100. An increase from 200 to 250 is a 25% increase. A drop from 200 to 150 is a 25% decrease.

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

Use the 'X is what % of Y?' mode. Enter the part value and the total. The calculator computes (part ÷ total) × 100. For example, 45 is 30% of 150. This is useful for converting test scores or comparing parts to a whole.

How do I calculate the price after a percentage discount?

First use 'What is X% of Y?' to find the discount amount: enter the discount percentage and the original price. Then subtract that from the original price manually. For example, 30% off $80: 30% of 80 = 24, so the sale price is $80 − $24 = $56.

How do I add a sales tax percentage to a price?

Use 'What is X% of Y?' with the tax rate and pre-tax price to find the tax amount, then add it to the original price. For example, 8.5% tax on $120: 8.5% of 120 = $10.20, so total = $130.20.

Typical workflow

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What is

What is Percentage Calculator?

The Percentage Calculator solves the three percentage questions people reach for a calculator to answer: finding a percentage of a value (what is 15% of 240?), finding what percentage one number is of another (30 is what percent of 200?), and calculating percentage change between two values (what is the percent increase from 80 to 100?).

Switch between modes with a single tap. Each mode shows only the two inputs it needs and returns the answer immediately — no formula memorization, no unit confusion, no rounding guesswork.

How to use

How to use Percentage Calculator

1. Select the mode that matches your question: 'What is X% of Y?', 'X is what % of Y?', or '% change from X to Y'.

2. Enter the two values in the input fields.

3. The result appears instantly below the inputs.

4. Switch modes at any time — the inputs clear automatically.

Example

Example

Mode: What is X% of Y?
  Percentage: 18
  Total value: 250
  Result: 45  (18% of $250 restaurant bill = $45 tip)

Mode: X is what % of Y?
  Part: 36
  Total: 144
  Result: 25%  (scored 36 out of 144 = 25%)

Mode: % change from X to Y
  Original: 80
  New: 100
  Result: +25%  (price rose from $80 to $100)

Common use cases

Common use cases

1. Shopping discounts: Find the sale price by calculating the discount percentage off the original price.

2. Test scores: Convert a raw score (34 out of 40) into a percentage grade.

3. Tax and tip: Calculate 8.5% sales tax or 20% tip on a bill amount.

4. Finance: Track portfolio growth — find the percent increase from last month's balance to this month's.

5. Business metrics: Calculate month-over-month revenue change or conversion rate shifts.

Frequently asked questions

Frequently asked questions

How do I calculate a percentage of a number?v
Use the 'What is X% of Y?' mode. Enter the percentage in the first field and the total value in the second. The result is (percentage ÷ 100) × total. For example, 20% of 150 = 0.20 × 150 = 30.
How do I calculate percent change?v
Use the '% change from X to Y' mode. Enter the original value and the new value. The formula is ((new − original) ÷ |original|) × 100. A positive result is an increase; negative is a decrease.
What is the difference between percent and percentage points?v
Percent (%) expresses a ratio relative to a total. Percentage points measure the arithmetic difference between two percentages. If a rate goes from 4% to 6%, that is a 2 percentage point increase, but a 50% relative increase. This calculator computes relative percent change.
Can I calculate a percentage decrease?v
Yes. Use the '% change from X to Y' mode and enter the larger number as the original and the smaller as the new value. The result will show as a decrease, displayed in red.