The Number.parseInt()
method parses a string argument and returns an integer of the specified radix or base.
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Syntax
Number.parseInt(string,[ radix])
Parameters
string
- The value to parse. If this argument is not a string, then it is converted to one using the
ToString
abstract operation. Leading whitespace in this argument is ignored. radix
Optional- An integer between
2
and36
that represents the radix (the base in mathematical numeral systems) of thestring
. Be careful—this does not default to10
!
Return value
An integer parsed from the given string
.
If the radix
is smaller than 2
or bigger than 36
, and the first non-whitespace character cannot be converted to a number, NaN
is returned.
Polyfill
if (Number.parseInt === undefined) { Number.parseInt = window.parseInt }
Examples
Number.parseInt vs parseInt
This method has the same functionality as the global parseInt()
function:
Number.parseInt === parseInt // true
and is part of ECMAScript 2015 (its purpose is modularization of globals). Please see parseInt()
for more detail and examples.
Specifications
Specification |
---|
ECMAScript (ECMA-262) The definition of 'Number.parseInt' in that specification. |
Browser compatibility
The compatibility table in 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.
Desktop | Mobile | Server | |||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|---|
parseInt | Chrome Full support 34 | Edge Full support 12 | Firefox Full support 25 | IE No support No | Opera Full support 21 | Safari Full support 9 | WebView Android Full support ≤37 | Chrome Android Full support 34 | Firefox Android Full support 25 | Opera Android Full support 21 | Safari iOS Full support 9 | Samsung Internet Android Full support 2.0 | nodejs Full support 0.12 |
Legend
- Full support
- Full support
- No support
- No support
See also
- The
Number
object it belongs to. - The global
parseInt()
method.