The Number.isFinite() method determines whether the passed value is a finite number — that is, it checks that the type of a given value is Number, and the number is neither positive Infinity, negative Infinity, nor NaN.
Number.isFinite()
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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.
Description
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.
Examples
Using isFinite
Number.isFinite(Infinity); // false Number.isFinite(NaN); // false Number.isFinite(-Infinity); // false Number.isFinite(0); // true Number.isFinite(2e64); // true Number.isFinite('0'); // false, would've been true with // global isFinite('0') Number.isFinite(null); // false, would've been true with // global isFinite(null)
Polyfill
if (Number.isFinite === undefined) Number.isFinite = function(value) { return typeof value === 'number' && isFinite(value); }
Specifications
| Specification |
|---|
| ECMAScript Language Specification # sec-number.isfinite |
Browser compatibility
| Desktop | Mobile | Server | ||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Chrome | Edge | Firefox | Internet Explorer | Opera | Safari | WebView Android | Chrome Android | Firefox for Android | Opera Android | Safari on IOS | Samsung Internet | Deno | Node.js | |
isFinite |
19
|
12
|
16
|
No
|
15
|
9
|
≤37
|
25
|
16
|
14
|
9
|
1.5
|
1.0
|
0.10.0
|
See also
- Polyfill of
Number.isFiniteincore-js - The
Numberobject it belongs to. - The global function
isFinite.
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https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Number/isFinite
