Subtraction (-)

Baseline Widely available

This feature is well established and works across many devices and browser versions. It’s been available across browsers since July 2015.

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

Try it

console.log(5 - 3); // Expected output: 2 console.log(3.5 - 5); // Expected output: -1.5 console.log(5 - "hello"); // Expected output: NaN console.log(5 - true); // Expected output: 4 

Syntax

js
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 using numbers

js
5 - 3; // 2 3 - 5; // -2 

Other non-BigInt values are coerced to numbers:

js
"foo" - 3; // NaN; "foo" is converted to the number NaN 5 - "3"; // 2; "3" is converted to the number 3 

Subtraction using BigInts

js
2n - 1n; // 1n 

You cannot mix BigInt and number operands in subtraction.

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

To do subtraction with a BigInt and a non-BigInt, convert either operand:

js
2n - BigInt(1); // 1n Number(2n) - 1; // 1 

Specifications

Specification
ECMAScript® 2026 Language Specification
# sec-subtraction-operator-minus

Browser compatibility

See also