How to Set Firefox's Cache to Zero

When you visit a Web page using Firefox, the browser automatically stores data like text, images, styling information and JavaScript files in a specific location on your hard disk called the cache. This helps Firefox load the page more quickly the next time you visit it, because the browser retrieves the data from your hard disk rather than over the Internet. However, when information on a Web page is updated, Firefox still uses the old files stored in the cache. You can force Firefox to always load pages fresh from the Internet by changing the size of the cache to zero, either via Firefox's Options menu or the "about:config" entry.

Click the "Tools" menu, and then select "Options." If you're using OS X, launch the settings utility by clicking the "Application" menu, and then selecting "Preferences." On Linux, click "Edit," and then select "Preferences."

Click the "Advanced" button, and then select the "Network" tab.

Check the box labeled "Override automatic cache management.”

Click the down arrow on the "Limit cache to" spin box to highlight the current cache size, and then type "0" (without the quotes). The cache still contains your old data at this point, so click the "Clear Now" button to clear the cache completely.

Click "OK" to save your new cache setting.

Type "about:config" (without the quotes) in the browser's address bar, and then press "Enter" to load your Firefox configuration settings. If Firefox displays the warning "This might void your warranty!", click the "I'll be careful, I promise!" button.

Type "browser.cache.disk.capacity" (without the quotes) in the search box to filter all settings except the one for cache size. This eliminates the possibility of changing the wrong setting by mistake.

Double-click the search result, type "0" (without the quotes) in the pop-up input box, and then click "OK."

Close the about:config tab when you are done.