LanguageTool
Free proofreading tool for OpenOffice, LibreOffice, Firefox, and Chrome. Also available as a standalone application. Supports about 20 languages (on different levels) and allows customization.
cocoAspell is Mac OS X interface to Aspell – A more intelligent Ispell – that is being developed by Kevin Atkinson. Aspell is an Open Source spell checker designed to...
cocoaspell is mac os x interface to aspell – a more intelligent ispell – that is being developed by kevin atkinson. aspell is an open source spell checker designed to eventually replace ispell. its main feature is that it does a much better job of coming up with possible suggestions than ispell does. in fact recent tests shows that it even does better than microsoft word 97's spell checker or just about any other spell checker i have seen. it also has support for checking (la)tex and html files, and run time support for other non english languages.
Free proofreading tool for OpenOffice, LibreOffice, Firefox, and Chrome. Also available as a standalone application. Supports about 20 languages (on different levels) and allows customization.
Freemium
Ginger Keyboard is the world’s first smartphone keyboard to offer advanced writing tools, including live as-you-type proofreading, alongside standard and advanced keyboard features like word prediction, autocorrect, emoji and swipe typing.
Freemium Windows Android iPhone Android Tablet iPad Chrome OS
Whether you’re writing a letter or an email, a simple click of a button will open some of the most comprehensive and useful language resources ever created.
Commercial
Grammar & Spelling Check; Free Online Proofreading; No Downloads...Allows you to find those pesky mistakes and correct them before your teacher does...
Freemium Web
This is a grammar checker that correct mistakes in your writing.
Freemium Android iPhone iPad Web
Grammar, Spelling, Punctuation, Phrase Usage, Dictionary, Thesaurus, AutoCorrect, AutoType, Readability, Sentence Analysis, Statistics Analysis, Interactive Checking (check-as-you-type), Online, Offline, and Mac OS X utility.
Commercial Mac OS X Web Mac Microsoft Office Word
Spelling checker. Checks HTML, TeX/LaTeX, RTF, and ASCII (plain text). Hotkey spell checking in WordPad, Notepad, Email, browsers, etc.
Free Personal Windows
SpellCheckPlus is a grammar checker that finds common spelling errors and grammatical mistakes in English.
Freemium Web