The Number.isFinite()
method determines whether the passed value is a finite number.
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Syntax
Number.isFinite(value)
Parameters
value
- The value to be tested for finiteness.
Return value
A Boolean
indicating whether or not the given value is a finite number.
Description
In comparison to the global isFinite()
function, this method doesn't forcibly convert the parameter to a number. This means only values of the type number, that are also finite, return true
.
Polyfill
if (Number.isFinite === undefined) Number.isFinite = function(value) { return typeof value === 'number' && isFinite(value); }
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)
Specifications
Specification |
---|
ECMAScript (ECMA-262) The definition of 'Number.isInteger' in that specification. |
Browser compatibility
The compatibility table in this page is generated from structured data. If you'd like to contribute to the data, please check out https://github.com/mdn/browser-compat-data and send us a pull request.
Desktop | Mobile | Server | |||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|---|
isFinite | Chrome Full support 19 | Edge Full support 12 | Firefox Full support 16 | IE No support No | Opera Full support 15 | Safari Full support 9 | WebView Android Full support ≤37 | Chrome Android Full support 25 | Firefox Android Full support 16 | Opera Android Full support 14 | Safari iOS Full support 9 | Samsung Internet Android Full support 1.5 | nodejs Full support 0.10 |
Legend
- Full support
- Full support
- No support
- No support