Super User is a question and answer site for computer enthusiasts and power users. It's 100% free, no registration required.

Sign up
Here's how it works:
  1. Anybody can ask a question
  2. Anybody can answer
  3. The best answers are voted up and rise to the top

We all know that we can't obfuscate HTML or Javascript. We need to remember that if the browser can read it, the user should be able to read it too.

Therefore, why is it that sometimes when we download a site locally, it does not work properly? This is especially true with Javascript. If the browser can display it properly, why does it breaks when it is stored locally? In short, what causes it to work differently locally than on the browser?

Thank you!


To give an example, I was trying to download this site:

To see how they made the animation, however the animation is not working locally.

share|improve this question

migrated from Aug 2 '13 at 22:07

This question came from our site for professional and enthusiast programmers.

First sentence in your 2nd paragraph has wrong grammar, please fix it. – MightyPork Aug 2 '13 at 19:05
That's using html5 canvas element with javascript. (The site you mentioned.) – Jack Aug 2 '13 at 19:41
Well for example ajax doesn't work when loading a site from disk – Esailija Aug 2 '13 at 20:02
up vote 1 down vote accepted


  • Dynamic pages - sometimes a URL doesn't give you a file, but the output of a program that runs on the server. This program may return different results each time.

  • Javascript - exact URLs a page may access won't be known unless all Javascript is executed, and, depending on the events that fire it off, it's possible some Javascript in a page never gets executed, or only gets executed at certain times, etc.

  • Filtering based on IP, etc. - sometimes a webserver may give you a different data for the same URL based on some attribute such as your IP, etc.

Purely static sites with no server-side processing should always be possible to download with a tool such as wget, but those types of sites are increasingly rare.

share|improve this answer

A website is not meant for downloading. When you do so, very often the dependencies get corrupt, links to script files don't work, images are missing.

Even though some browsers have a function to download whole website, it is not perfect, and is bound to fail on dynamic websites that use server-side scripts, such as PHP.

share|improve this answer
+1 for mentioning server-side scripts. – Dryden Long Aug 2 '13 at 19:14

Frequently it's because the links in the HTML and/or JavaScript code, including CSS, etc., are still referencing the online site, not the locally downloaded files. You would have to go through all of the files and update any links so that they reference the local files rather than the original site. In addition, some parts of the site may be dynamically loaded - i.e., the mark up that is actually displayed is different than that originally downloaded by the browser. When you "save" the files out of the browser, it likely saves the response to the original request, not the current document object model that reflects what is displayed in the browser.

share|improve this answer
When using the Scrapbook Firefox extension it downloads every stylesheets and scripts from a site to keep a copy locally, yet it is still not working 100%. What I am wondering is what cause this little things to not work properly, like a navbar 2px lower, a CSS animation not appearing etc. – Vilarix Aug 2 '13 at 19:16

If you download a webpage you haven't necessarily downloaded linked files, e.g. images, css, javascript. Even if you did have them you'd have to change the references to them, or have them in proper locations for them to work. "/mycss.css" would have to be in the main folder "mycss.css" would have to be in the same folder as the current page, etc.

share|improve this answer

If you'd like to download a whole website (or portion of one), check out HTTrack. It will download the site or part of the site and change all the dependencies to work locally as needed.

share|improve this answer
I tried it but I prefer the Firefox extension Scrapbook. They both don't make the site work 100% like the original though which leads me to this question: why, even when editing the links, it is still not displaying the site like it was in the browser? – Vilarix Aug 2 '13 at 19:18

Right click -> View Source -> Click on all the js/css files, save those as well. Make sure you reference the files on your computer.

share|improve this answer

Your Answer


By posting your answer, you agree to the privacy policy and terms of service.

Not the answer you're looking for? Browse other questions tagged or ask your own question.