Number.parseInt()
Parses a string argument and returns an integer of the specified radix.
Syntax
Number.parseInt(string, radix)Parameters
| Name | Type | Required | Description |
|---|---|---|---|
string | string | Yes | The value to parse. Leading whitespace is ignored. |
radix | number | No | An integer between 2 and 36 giving the base. Strongly recommended to pass 10. |
Returns
number — The parsed integer, or NaN if it cannot be parsed.
Examples
console.log(Number.parseInt('42px', 10));
Output
42
console.log(Number.parseInt('0xFF', 16), Number.parseInt('1010', 2));
Output
255 10
Notes
Always pass the radix - without it, leading "0x" is treated as hex. Truncates
rather than rounds and stops at the first invalid character. Identical to the
global `parseInt`.
Browser & runtime support
| Environment | Since version |
|---|---|
| chrome | 34 |
| firefox | 25 |
| safari | 9 |
| edge | 12 |
| node | 0.12 |