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 1. References
 2. JavaScript
 3. JavaScript
 4. Standard built-in objects
 5. Number
 6. Number.isFinite()

Article Actions
 * English (US)


IN THIS ARTICLE

 * Try it
 * Syntax
 * Examples
 * Specifications
 * Browser compatibility
 * See also

RELATED TOPICS

 1.  Standard built-in objects
 2.  Number
 3.  Properties
      1. Number.EPSILON
      2. Number.MAX_SAFE_INTEGER
      3. Number.MAX_VALUE
      4. Number.MIN_SAFE_INTEGER
      5. Number.MIN_VALUE
      6. Number.NaN
      7. Number.NEGATIVE_INFINITY
      8. Number.POSITIVE_INFINITY

 4.  Methods
      1.  Number.isFinite()
      2.  Number.isInteger()
      3.  Number.isNaN()
      4.  Number.isSafeInteger()
      5.  Number.parseFloat()
      6.  Number.parseInt()
      7.  Number.prototype.toExponential()
      8.  Number.prototype.toFixed()
      9.  Number.prototype.toLocaleString()
      10. Number.prototype.toPrecision()
      11. Number.prototype.toString()
      12. Number.prototype.valueOf()

 5.  Inheritance:
 6.  Function
 7.  Properties
      1. Non-standard Deprecated Function.prototype.arguments
      2. Non-standard Deprecated Function.prototype.caller
      3. Non-standard Function.prototype.displayName
      4. Function.prototype.length
      5. Function.prototype.name
      6. Function.prototype.prototype

 8.  Methods
      1. Function.prototype.apply()
      2. Function.prototype.bind()
      3. Function.prototype.call()
      4. Function.prototype.toString()

 9.  Object
 10. Properties
      1. Object.prototype.constructor
      2. Deprecated Object.prototype.__proto__

 11. Methods
      1.  Deprecated Object.prototype.__defineGetter__()
      2.  Deprecated Object.prototype.__defineSetter__()
      3.  Deprecated Object.prototype.__lookupGetter__()
      4.  Deprecated Object.prototype.__lookupSetter__()
      5.  Object.prototype.hasOwnProperty()
      6.  Object.prototype.isPrototypeOf()
      7.  Object.prototype.propertyIsEnumerable()
      8.  Object.setPrototypeOf()
      9.  Object.prototype.toLocaleString()
      10. Object.prototype.toString()
      11. Object.prototype.valueOf()


IN THIS ARTICLE

 * Try it
 * Syntax
 * Examples
 * Specifications
 * Browser compatibility
 * See also


NUMBER.ISFINITE()

The Number.isFinite() 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.


TRY IT




SYNTAX

Number.isFinite(value)


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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


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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


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SPECIFICATIONS

SpecificationECMAScript Language Specification
# sec-number.isfinite


BROWSER COMPATIBILITY

Report problems with this compatibility data on GitHub

desktopmobileserver
Chrome

Edge

Firefox

Opera

Safari

Chrome Android

Firefox for Android

Opera Android

Safari on iOS

Samsung Internet

WebView Android

Deno

Node.js

isFinite
Full support
Chrome19
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Edge12
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Firefox16
Toggle history
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Opera15
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Safari9
Toggle history
Full support
Chrome Android25
Toggle history
Full support
Firefox for Android16
Toggle history
Full support
Opera Android14
Toggle history
Full support
Safari on iOS9
Toggle history
Full support
Samsung Internet1.5
Toggle history
Full support
WebView Android4.4
Toggle history
Full support
Deno1.0
Toggle history
Full support
Node.js0.10.0
Toggle history


LEGEND

Tip: you can click/tap on a cell for more information.

Full supportFull support
The compatibility table on 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.


SEE ALSO

 * Polyfill of Number.isFinite in core-js
 * The Number object it belongs to
 * The global function isFinite


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Last modified: Dec 13, 2022, by MDN contributors

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