Grammar checkers

LanguageTool is a free and open-source grammar, style, and spell checker, and all its features are available for download. The LanguageTool website connects to a proprietary sister project called LanguageTool Premium (formerly LanguageTool Plus), which provides improved error detection for English and German, as well as easier revision of longer texts, following the open-core model.

computer program that verifies written text for grammatical correctness

online translation and linguistic tools