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Number.isFinite()

Baseline Widely available

This feature is well established and works across many devices and browser versions. Its been available across browsers since 2015 9.

Number.isFinite() .

Number.isFinite() . , Infinity, Infinity, NaN .

In this article

console.log(Number.isFinite(1 / 0));
// Expected output: false

console.log(Number.isFinite(10 / 5));
// Expected output: true

console.log(Number.isFinite(0 / 0));
// Expected output: false

js
Number.isFinite(value)

value

.

true, false .

isFinite()

js
Number.isFinite(Infinity); // false
Number.isFinite(NaN); // false
Number.isFinite(-Infinity); // false

Number.isFinite(0); // true
Number.isFinite(2e64); // true

Number.isFinite() global isFinite()

isFinite() . , true false .

js
isFinite("0"); // true;  0  
Number.isFinite("0"); // false
isFinite(null); // true;  0  
Number.isFinite(null); // false

Specification
ECMAScript 2027 LanguageSpecification
# sec-number.isfinite

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