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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 - 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

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

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

Other non-BigInt values are coerced to numbers:

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

Subtraction using BigInts

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

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

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

Specifications

Browser compatibility

Desktop Mobile Server
Chrome Edge Firefox Opera Safari Chrome Android Firefox for Android Opera Android Safari on IOS Samsung Internet WebView Android WebView on iOS Bun Deno Node.js
Subtraction 1 12 1 3 1 18 4 10.1 1 1.0 4.4 1 1.0.0 1.0 0.10.0

See also

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Licensed under the Creative Commons Attribution-ShareAlike License v2.5 or later.
https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Operators/Subtraction