Free

Free Percentage Calculator

Three calculators in one: X% of Y, X is what percent of Y, and percent increase or decrease — instant answers.

Free tool · No sign-up · Private

What is 20% of 150?

Percentage (%)

Of value

Enter both numbers above — the answer appears instantly.

Private by design. Everything runs 100% in your browser — your numbers are never uploaded, stored, or sent anywhere.

About this tool

About the percentage calculator

Percentages show up everywhere — discounts, tips, taxes, grades, salary raises, and business growth. This free calculator bundles the three questions people actually ask: what is X% of Y (discounts and tips), X is what percent of Y (grades and shares), and the percent change between two numbers (growth, inflation, price drops).

Switch modes with one tap; answers update live as you type. The increase/decrease mode color-codes results — green for growth, red for drops — so the direction is obvious at a glance. Like every YATools utility, it runs entirely in your browser with nothing uploaded.

How it works

Three steps to your answer

Pick a mode

X% of Y, X is what % of Y, or percent increase/decrease — one tap to switch.

Enter two numbers

Type both values. The answer computes live — no button to press.

Read the answer

See the result with a plain-English explanation, e.g. “120 → 150 is a 25% increase”.

FAQ

Percentage questions

How do I calculate X percent of Y?

Divide the percentage by 100, then multiply by Y. Example: 20% of 150 = (20 ÷ 100) × 150 = 30. Use the first mode on this calculator and it does the math instantly.

How do I find what percent X is of Y?

Divide X by Y and multiply by 100. Example: 30 is what percent of 150? (30 ÷ 150) × 100 = 20%. The second mode here handles it.

How is percent increase or decrease calculated?

Subtract the original from the new value, divide by the original, and multiply by 100. Going from 120 to 150 is ((150 − 120) ÷ 120) × 100 = 25% increase. A negative result means a decrease.

What's the difference between percent and percentage points?

A classic mix-up: if a rate rises from 10% to 15%, that's a 5 percentage-point rise but a 50% increase (5 ÷ 10 × 100). This calculator shows percent change, which is the relative figure.

Is my data private?

Yes. All calculations run entirely in your browser — your numbers are never uploaded, stored, or sent anywhere.

Keep exploring