CalcMate

Everyday math tool

Percentage Calculator

Calculate percentages, relative change, discounts, markups, and adjusted values in a few clicks.

What do you want to calculate?

Percentage

Value

Result

Percentage of

Your result will appear here

Percentage guide

Common percentage formulas

Percentage of a value

Value × Percentage ÷ 100

Find the percentage

Part ÷ Whole × 100

Percentage change

(New − Original) ÷ |Original| × 100

Frequently asked questions

How do I calculate a percentage of a number?

Multiply the number by the percentage and divide by 100. For example, 15% of 200 is 200 × 15 ÷ 100 = 30.

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

Divide the first number by the reference number and multiply by 100. For example, 25 is 20% of 125.

How is percentage change calculated?

Subtract the original value from the new value, divide by the absolute original value, and multiply by 100. A positive result is an increase and a negative result is a decrease.

What is the difference between percentage and percentage points?

Percentage points measure the arithmetic difference between two percentages. A change from 20% to 25% is 5 percentage points but a 25% relative increase.

Can a percentage be greater than 100%?

Yes. A value can be more than 100% of another value, and an increase can exceed 100%.

Practical guidance

Use the Percentage Calculator with confidence

Find a percentage of a value, one number as a percentage of another, percentage change, or an increased or decreased amount. Includes examples.

Worked example

Choose Percentage of and enter 15 and 2,000: the result is 300. In Find percentage, 300 and 2,000 gives 15%. In % change, 800 and 900 gives a 12.5% increase.

Assumptions and limits

Results display up to six decimal places. Floating-point precision still applies. The negative-base convention may differ from a spreadsheet using the signed original value.

How to read the result

Percentage of produces an amount; Find percentage and % change produce a percentage. The change mode uses the absolute original value, so changing −100 to −50 is displayed as a 50% increase.

Inputs and units

Choose the operation first, then follow its two field labels. Both values must use the same unit when finding a percentage or change. A reference or original value used as a divisor cannot be zero.

Formula and variables

Percent of = value × percent / 100. Find percentage = part / whole × 100. Change = (new − original) / |original| × 100. Adjustment = value × (1 ± percent / 100).

Comparisons and common mistakes

A change from 20% to 25% is five percentage points, but a 25% relative increase. Use Discount to turn a price reduction into savings, or GST for a tax-inclusive price.

Does increasing and then decreasing by the same percent restore the original?

No. Increasing 100 by 20% gives 120; decreasing 120 by 20% gives 96 because the second percentage uses a different base.

Guide checked 2026-09-11

Guide checked against the web calculator by an automated coding assistant. Independent professional review is not recorded.

Substantive guide update: 2026-09-11.

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