Skip to content

The Number parseInt() method

Find out all about the JavaScript parseInt() method of the Number object

Parses the argument as an integer number and returns it:

Number.parseInt('10') //10
Number.parseInt('10.00') //10
Number.parseInt('237,21') //237
Number.parseInt('237.21') //237
Number.parseInt('12 34 56') //12
Number.parseInt(' 36 ') //36
Number.parseInt('36 is my age') //36

As you can see Number.parseInt() is pretty flexible. It can also convert strings with words, extracting the first number, but the string must start with a number:

Number.parseInt('I am Flavio and I am 36') //NaN

You can add a second parameter to specify the radix. Radix 10 is default but you can use octal or hexadecimal number conversions too:

Number.parseInt('10', 10) //10
Number.parseInt('010') //10
Number.parseInt('010', 8) //8
Number.parseInt('10', 8) //8
Number.parseInt('10', 16) //16
→ Get my JavaScript Beginner's Handbook

I wrote 17 books to help you become a better developer, download them all at $0 cost by joining my newsletter

JOIN MY CODING BOOTCAMP, an amazing cohort course that will be a huge step up in your coding career - covering React, Next.js - next edition February 2025

Bootcamp 2025

Join the waiting list