Use this calculator to verify a hand calculation, normalize a value before another tool, or make the exact arithmetic convention explicit in a reproducible workflow.

Percentage A

First percentage.

Percentage B

Second percentage.

The formula below determines the tool output. Percentage points: Difference in percentage points (A minus B).^[1]

Calculations use JavaScript number arithmetic. Binary floating-point representation can make some decimal results inexact, and values outside the supported numeric range can overflow or lose precision. Round only for presentation unless the selected rounding tool is itself the intended operation.

Use the inverse operation to check a result when one exists: addition pairs with subtraction, multiplication with division, and powers with roots. For rounding or normalization tools, retain the unmodified value when later calculations still require full precision.

• Basis Points Calculator

  Convert a percentage to basis points (multiply by one hundred).

• Per Mille to Decimal Converter

  Convert a per mille value (parts per thousand) to its decimal ratio.

• Ratio to Percentage Converter

  Convert a ratio to a percentage by multiplying by one hundred.