What types of percentage calculations does this support?

Three modes: (1) What is X% of Y? (2) X is what percent of Y? (3) Percentage change from X to Y.

How do I calculate a discount?

Use the "X% of Y" mode. Enter the original price as Y and the discount rate as X to get the discount amount.

How do I calculate percentage increase or decrease?

Use the percentage change mode. Enter the original value and the new value and the tool calculates the percentage difference automatically.

Why is a percentage calculator faster than mental math?

It removes the arithmetic mistakes that creep into multi-step problems — discount + tax, percent change between two large numbers, or finding the original price before a markup — especially when accuracy matters (invoices, taxes, grades).

When should I use percentage change vs percentage difference?

Use percentage change when there is a clear before/after (sales went from $100 to $120 = +20%). Use percentage difference when neither value is the baseline (comparing two products' prices symmetrically).

Percentage Calculator

Calculators· 14 tools

Free online percentage calculator. Calculate what percent of a number is, find what percentage one number is of another, and compute percentage increase or decrease. Instant results, no signup required.

What is X% of Y?

% of

X is what % of Y?

is what % of

% Change from X to Y

→

Frequently Asked Questions

References

Percent — NIST Guide for the Use of SI — National Institute of Standards and Technology

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Frequently Asked Questions

References and sources

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