JavaScript: parseInt() function

Description

The parseInt is used to get a numeric value from a string. parseInt is a top-level function and is not associated with any object.

Syntax

parseInt(numString, radix)

Parameters

numString: Required. A string that represents the value to test.

radix: Optional. An integer that represents the radix of the return value. A value between 2 and 36 indicating the base of the number contained in numString. For example, a radix of ten indicates to convert to a decimal number, eight octal, sixteen hexadecimal, and so on.

Example of parseInt() function

The following example shows how to use the parseInt() function.

JavaScript Code:

console.log('"21" -> '+parseInt("21"));
console.log('"21.42" -> '+parseInt("21.42"));
console.log('"100 234 54" -> '+parseInt("100 234 54"));
console.log('"89 Math" ->'+parseInt("89 Math"));
console.log('"Math 89" ->'+parseInt("Math 89"));
console.log();
console.log(parseInt("100",10));
console.log(parseInt("001"));
console.log(parseInt("100",8));
console.log(parseInt("0x10"));
console.log(parseInt("10",16));

View the example in the browser

Live demo:

See the Pen parselnt-function-1 by w3resource (@w3resource) on CodePen.

Previous: JavaScript: isNaN() function
Next: JavaScript: parseFloat() function