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.
After the Deadline is an intelligent language checking server, extensions are available for many applications.
We use artificial intelligence and natural language processing technology to find your writing errors and offer smart suggestions.
Our technology is available under the GNU General Public License.
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