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Number.isFinite()

The Number.isFinite() static method determines whether the passed value is a finite number — that is, it checks that a given value is a number, and the number is neither positive Infinity, negative Infinity, nor NaN.

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Syntax

Number.isFinite(value)

Parameters

value: The value to be tested for finiteness.

Return value

The boolean value true if the given value is a finite number. Otherwise false.

Examples

Using isFinite()

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

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

Difference between Number.isFinite() and global isFinite()

In comparison to the global isFinite() function, this method doesn't first convert the parameter to a number. This means only values of the type number and are finite return true, and non-numbers always return false.

isFinite("0"); // true; coerced to number 0
Number.isFinite("0"); // false
isFinite(null); // true; coerced to number 0
Number.isFinite(null); // false

Specifications

Specification
ECMAScript Language Specification # sec-number.isfinite

Browser compatibility

	Desktop						Mobile						Server
	Chrome	Edge	Firefox	Opera	Safari	Chrome Android	Firefox for Android	Opera Android	Safari on IOS	Samsung Internet	WebView Android	Deno	Node.js
`isFinite`	19	12	16	15	9	25	16	14	9	1.5	4.4	1.0	0.10.0