parseint-function-javascript.md

title	ms.custom	ms.date	ms.prod	ms.reviewer	ms.suite	ms.technology	ms.tgt_pltfrm	ms.topic	f1_keywords	dev_langs	helpviewer_keywords	ms.assetid	caps.latest.revision	author	ms.author	manager
parseInt Function (JavaScript) | Microsoft Docs		01/18/2017	windows-client-threshold			devlang-javascript		language-reference	parseInt	JavaScript TypeScript DHTML	parseInt method	e86471af-2a0e-4359-83af-f1ac81e51421	24	mikejo5000	mikejo	ghogen

parseInt Function (JavaScript)

Converts a string to an integer.

Syntax

parseInt(numString, [radix])   

Parameters

numString
Required. A string to convert into a number.

radix
Optional. A value between 2 and 36 that specifies the base of the number in numString. If this argument is not supplied, strings with a prefix of '0x' are considered hexadecimal. All other strings are considered decimal.

Remarks

The parseInt function returns an integer value equal to the number contained in numString. If no prefix of numString can be successfully parsed into an integer, NaN (not a number) is returned.

parseInt("abc");     // Returns NaN.  
parseInt("12abc");   // Returns 12.  

You can test for NaN using the isNaN function.

Requirements

[!INCLUDEjsv1]

Applies To: Global Object

Note

Starting in [!INCLUDEjsv9textspecific], the parseInt function does not treat a string that has a prefix of '0' as an octal. When you are not using the parseInt function, however, strings with a prefix of '0' can still be interpreted as octals. See Data Types for information about octal integers.

See Also

isNaN Function
parseFloat Function
String Object
valueOf Method (Object)