Is the percentage calculator free?

Yes — 100% free, no signup, no usage limits.

Does it save my data?

No. Inputs are processed in your browser and never uploaded to a server.

Can I use it on mobile?

Yes. The interface is fully responsive and works on iOS and Android.

How is percent change calculated?

Percent change = ((new − old) / |old|) × 100. A positive result is an increase, negative is a decrease.

Percentage Calculator — %, % of, % change

Find X% of Y, what percent X is of Y, or the percent change between two numbers.

Percent (X)Of (Y)

Result

15% of 80 = 12

How to use

Step 1: Pick the mode (of / is / change)
Step 2: Enter the two numbers
Step 3: Read the answer instantly

Frequently asked questions

The percentage calculator handles the three percent operations you actually use: 'what is X% of Y' for tips and tax, 'X is what percent of Y' for grades and ratios, and 'percent change from X to Y' for growth and discounts..