JavaScript Number.parseInt()

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Examples

Number.parseInt("10");
Number.parseInt("10.00");
Number.parseInt("10.33");
Number.parseInt("34 45 66");
Number.parseInt(" 60 ");
Number.parseInt("40 years");
Number.parseInt("He was 40");

Try it Yourself »

Number.parseInt("10", 10);
Number.parseInt("010");
Number.parseInt("10", 8);
Number.parseInt("0x10");
Number.parseInt("10", 16);

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Description

The Number.parseInt method parses a value as a string and returns the first integer.

A radix parameter specifies the number system to use:

2 = binary, 8 = octal, 10 = decimal, 16 = hexadecimal.

If radix is omitted, JavaScript assumes radix 10. If the value begins with "0x", JavaScript assumes radix 16.

Notes

If the first character cannot be converted, NaN is returned.

Leading and trailing spaces are ignored.

Only the first integer found is returned.

Syntax

Number.parseInt(string, radix)

Parameters

Parameter	Description
value	Required. The value to be parsed.
radix	Optional. Default is 10. A number (2 to 36) specifying the number system.

Return Value

Type	Description
Number	NaN if no integer is found.

Browser Support

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

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