UNB/ CS/ David Bremner/ teaching/ cs2613/ books/ mdn/ Reference/ Operators/ Subtraction (-)

The subtraction (-) operator subtracts the two operands, producing their difference.

Syntax

x - y

Description

The - operator is overloaded for two types of operands: number and BigInt. It first coerces both operands to numeric values and tests the types of them. It performs BigInt subtraction if both operands become BigInts; otherwise, it performs number subtraction. A TypeError is thrown if one operand becomes a BigInt but the other becomes a number.

Examples

Subtraction with numbers

// Number - Number -> subtraction
5 - 3; // 2

// Number - Number -> subtraction
3 - 5; // -2

Subtraction with non-numbers

// String - Number -> subtraction
"foo" - 3; // NaN; "foo" is converted to the number NaN

// Number - String -> subtraction
5 - "3"; // 2; "3" is converted to the number 3

Subtraction with BigInts

// BigInt - BigInt -> subtraction
2n - 1n; // 1n

You cannot mix BigInt and number operands in subtraction.

2n - 1; // TypeError: Cannot mix BigInt and other types, use explicit conversions
2 - 1n; // TypeError: Cannot mix BigInt and other types, use explicit conversions

Specifications

Browser compatibility

See also