JavaScript Number isFinite()

Examples

Is 123 finite?

Number.isFinite(123)
Try it Yourself »
Number.isFinite("123")
Try it Yourself »

Description

The Number.isFinite() method returns true if a number is a finite number.

Infinite (not finite) numbers are Infinity, -Infinity, or NaN

Otherwise it returns false.


Difference Between isFinite() and Number.isFinite()

isFinite() returns true if a value is a finite number.

Number.isFinite() returns true if a number is a finite number.

In other words:

isFinite() converts the value to a number before testing it.

Examples

// This returns true
isFinite(123)
Try it Yourself »
// This returns false
Number.isFinite("123")
Try it Yourself »

Syntax

Number.isFinite(value)

Parameters

Parameter Description
value Required.
The value to be tested.

Return Value

Type Description
A booleantrue if the value is a finite Number, otherwise false.


More Examples

Number.isFinite(+1.23)
Number.isFinite(-1.23)
Number.isFinite('2005/12/12')
Try it Yourself »
Number.isFinite(5-2)
Number.isFinite(5/2)
Number.isFinite(0)
Number.isFinite(0/0)
Number.isFinite(Infinity)
Number.isFinite(-Infinity)
Number.isFinite(NaN)
Try it Yourself »

Browser Support

Number.isFinite() is an ECMAScript6 (ES6) feature.

ES6 (JavaScript 2015) is supported in all modern browsers since June 2017:

Chrome 51 Edge 15 Firefox 54 Safari 10 Opera 38
May 2016 Apr 2017 Jun 2017 Sep 2016 Jun 2016

Number.isFinite() is not supported in Internet Explorer.


Copyright 1999-2023 by Refsnes Data. All Rights Reserved.