# [JAVASCRIPT] – PARSING INTEGERS WITH TRAILING “0” WITH PARSEINT (IE9-11)

> URL: https://crodrigues.com/javascript-parsing-integers-trailing-0-parseint/  
> Author: Carlos Rodrigues  
> Published: 2014-09-29  
> Updated: 2026-10-21  
> Categories: Uncategorized  
> Tags: internet explorer, javascript, legacy  

_We are always learning, sometimes not the best way  As most of the times, when I develop in JavaScript, I end up using the chrome…
Continue reading[JAVASCRIPT] – PARSING INTEGERS WITH TRAILING “0” WITH PARSEINT (IE9-11)_
We are always learning, sometimes not the best way

![:)](https://web.archive.org/web/20201026182242im_/http://crodrigues.com/wp-includes/images/smilies/icon_smile.gif)

As most of the times, when I develop in JavaScript, I end up using the chrome debugger as it’s lighter than its IE counterpart.

On a project, I had to retrieve some dates from DOM elements and process them, place the elements in the proper position.

The dates were on the following format: “MM:YY”. It means that February is “02” and September is “09”.

While on chrome the parsing of those texts were ok:

parseInt(“02″) -> 2

parseIng(“09″) -> 9

on IE9 and IE11 they were inconsistent:

parseInt(“02″) -> 2

parseInt(“09″) -> 0

Apparently parseInt works in OCTAL mode by default when the string starts with a “0”. Since in octal mode 8 and 9 don’t exist, it returns 0, for IE 8 Document mode.

Like it or not, it is designed like that, when you use IE 8 Document Mode (which you necessarily use for sharepoint 2010).

JsBin (set your browser to IE 8 Document Mode and ignore the JSBIN javascript errors caused it causes):

[JsBIN](https://web.archive.org/web/20201026182242/http://jsbin.com/cetobumulisu/1/edit)

So, it’s necessary to force the decimal mode:

parseInt(“09″,10) -> 9

So from now on, I’ll always specify the decimal mode, just in case.