Free grammar-checking software that users can download include the Ginger Grammar Checker and Grammarly. They are available on GingerSoftware.com and Grammarly.com, respectively. Users can also download After the Deadline, a free grammar-checking extension for Google Chrome, through the Chrome Web Store.
The Ginger Grammar Checker is capable of analyzing the context of a sentence and automatically correcting grammar mistakes such as verb agreement, misused singular and plural words, and tense errors. Grammarly integrates itself with Google Chrome and detects grammar mistakes in text boxes of social media websites such as Facebook and Twitter. It covers over 250 grammar mistakes, corrects contextual spelling errors and improves vocabulary. Once a user installs After the Deadline, the extension adds a small ABC icon in text boxes that users can click to initiate automatic proofreading.