What is a percentage?

A percentage is a way of expressing a number as a fraction of 100. It is denoted with the symbol '%' and commonly used to represent a portion of a whole. For example, if there are 100 cars in a garage and 25 of them are white, 25% of the cars are white.

How do you calculate a percentage of a number?

To calculate a percentage of a number, divide the percentage by 100 and multiply by the number. For example, 25% of 200 = (25 ÷ 100) × 200 = 50. Use Percentii's 'What is X% of Y?' calculator for instant results.

How do I calculate percentage increase or decrease?

To calculate percentage change, subtract the original value from the new value, divide by the absolute value of the original, and multiply by 100. A positive result is an increase; a negative result is a decrease. Percentii's '% Increase/Decrease' calculator handles this instantly.

What is the difference between percent change and percent difference?

Percent change compares a new value to an original value and has a direction (increase or decrease). Percent difference compares two values without a direction — it divides the absolute difference by the average of the two values. Use Percentii's '% Difference' calculator for the latter.

How do I add or subtract a percentage from a number?

To add a percentage, multiply the number by the percentage (divided by 100) and add the result to the original. To subtract, multiply and subtract instead. For example, adding 15% to 200: 200 + (15 ÷ 100 × 200) = 230. Percentii has dedicated 'Add X% to Y' and 'Deduct X% from Y' calculators.

Is Percentii free to use?

Yes, Percentii is completely free to use. All calculations run locally in your browser with no sign-ups, ads, or data collection required. Your numbers never leave your device.

Does Percentii store my calculation history?

Percentii offers an optional history feature. You can save any calculation result by clicking the save icon, and it will appear in the History panel so you can revisit it later. History is stored securely and can be cleared at any time.

Percentii - Free Percentage Calculator

Percentii is a free online percentage calculator with 6 powerful tools: calculate the percentage of a number, find what percentage one number is of another, calculate percentage increase or decrease, add or subtract a percentage, and compute the percent difference between two values.

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