S3 Translator is a free Firefox extension that adds the power of Google Translate’s automatic translations to your Firefox browser! It supports the translation of a selected text of an entered phrase or translates a whole webpage between any of 80+ languages.
In addition, the extension can auto-detect the language of the source text. And in recent versions, you can now also use this application to learn a language. This is something we found on the Homepage of this tool, but we did not test this feature.
There are a lot of simple and complex extensions for the Firefox browser, but they all have the same problem. When translating, the format of the selected text is lost. This Translator application retains the HTML formatting of the web pages. Therefore, it provides you with a better reading experience in regard to the rest of the webpage.
Available for: Windows, Mac OS, Linux
Don’t Forget Security
This translator application is an add-on for Firefox and uses the Google Translator service. As such, you should use the application with caution. We would recommend that you do not use this app to translate any confidential material. You should always be aware that content that gets translated by the Google service might end up in Google’s data storage. And from there, your translations could be made available to someone else translating similar content.