Grammarly is an AI writing assistant that checks grammar and spelling, rewrites sentences, adjusts tone and gives feedback on how a text may be received. It also includes an AI chat and an AI detector, and business plans add style guides and analytics. Grammarly is available as desktop apps for Windows and Mac, browser extensions, add-ins for Microsoft Office and Google Docs, and mobile apps. In 2025 the company behind it renamed itself Superhuman and now groups Grammarly, the Coda workspace and Superhuman Mail in one suite.
The data controller for users in the EU, the UK and Switzerland is Superhuman Platform Inc. in San Francisco. The company states that data may be processed outside the user's country; for transfers to the United States it is certified under the EU-US Data Privacy Framework. The privacy policy describes no data residency options. The software is proprietary. For a European organisation, text entered into the assistant is processed by a US company, so the sensitivity of the content deserves review.