How is percentage change calculated?

It is (new value − original value) ÷ original value × 100. A positive result is an increase and a negative result is a decrease.

Why is a result unavailable when the comparison value is zero?

A ratio cannot divide by zero. “X is what percent of Y” needs a non-zero Y, and percentage change needs a non-zero original value.

Can I enter decimal or negative values?

Yes. The fields parse decimal and signed numeric input; the meaning of a negative percentage depends on the calculation selected.

Percentage Calculator

LocalFree

Answer the three everyday percentage questions instantly — a share of a number, a ratio as a percent, and percentage change.

% of a numberX is what % of Y% change

Input

% of

Result

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About percentage calculations

Percentages turn up everywhere — discounts, taxes, tips, grades, statistics, and finance. This calculator covers the three questions people ask most: what is X percent of a number, what percentage one number is of another, and the percentage increase or decrease between two values. Type your figures and the answer updates instantly, all computed locally in your browser.

How to use Percentage Calculator

1Choose percentage of a number, one value as a percentage of another, or percentage change.
2Enter both numbers; the result updates immediately.

Frequently asked questions

How is percentage change calculated?: It is (new value − original value) ÷ original value × 100. A positive result is an increase and a negative result is a decrease.
Why is a result unavailable when the comparison value is zero?: A ratio cannot divide by zero. “X is what percent of Y” needs a non-zero Y, and percentage change needs a non-zero original value.
Can I enter decimal or negative values?: Yes. The fields parse decimal and signed numeric input; the meaning of a negative percentage depends on the calculation selected.