How do I calculate a percentage of a number?

Multiply the number by the percentage and divide by 100. For example, 20% of 50 = (50 × 20) / 100 = 10.

How do I calculate percentage change?

Subtract the original value from the new value, divide by the original value, and multiply by 100.

Calculate percentages, percentage of a number, and percentage change between two values.

Value

Percentage (%)

Original value

New value

Part

Whole

Add, subtract, multiply, and divide fractions. Results are automatically simplified to lowest terms.

Find the Least Common Multiple (LCM) and Highest Common Factor (HCF) of two or more numbers.

Check whether a number is prime. Also shows all prime factors if the number is composite.

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