JavaScript parseInt()
Example
Parse different values:
parseInt("10");
parseInt("10.00");
parseInt("10.33");
parseInt("34 45 66");
parseInt(" 60 ");
parseInt("40 years");
parseInt("He was 40");
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Description
The 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.
Older browsers will return 8 for parseInt("010"). Older versions of ECMAScript used octal (radix 8) for values beginning with "0". From ECMAScript 5 (2009) default is decimal (radix 10).
Syntax
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 |
| A number. | NaN if no integer is found. |
Browser Support
parseInt() is an ECMAScript1 (ES1) feature.
ES1 (JavaScript 1997) is fully supported in all browsers:
| Chrome | Edge | Firefox | Safari | Opera | IE |
| Yes | Yes | Yes | Yes | Yes | Yes |
More Examples
Parse different values:
parseInt("10", 10);
parseInt("010");
parseInt("10", 8);
parseInt("0x10");
parseInt("10", 16);
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