The global isFinite()
function determines whether the passed value is a finite number. If needed, the parameter is first converted to a number.
isFinite()
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Syntax
isFinite(testValue)
Parameters
-
testValue
-
The value to be tested for finiteness.
Return value
Description
isFinite
is a function property of the global object.
You can use this function to determine whether a number is a finite number. The isFinite
function examines the number in its argument. If the argument is NaN
, positive infinity, or negative infinity, this method returns false
; otherwise, it returns true
.
Examples
Using isFinite
isFinite(Infinity); // false isFinite(NaN); // false isFinite(-Infinity); // false isFinite(0); // true isFinite(2e64); // true isFinite(910); // true isFinite(null); // true, would've been false with the // more robust Number.isFinite(null) isFinite('0'); // true, would've been false with the // more robust Number.isFinite("0")
Specifications
Specification |
---|
ECMAScript Language Specification # sec-isfinite-number |
Browser compatibility
Desktop | Mobile | Server | ||||||||||||
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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 |
1
|
12
|
1
|
4
|
3
|
1
|
1
|
18
|
4
|
10.1
|
1
|
1.0
|
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/Global_Objects/isFinite