Grammarly

Grammarly is one of the few AI-adjacent tools that has successfully crossed from utility into daily habit for a large number of writers. With over 30 million daily active users, it is embedded into browsers, email clients, word processors, and messaging apps, which means many people use it without consciously opening a separate tool.

The core product is a writing assistant that catches grammar, spelling, punctuation, and style issues in real time. What distinguishes it from a basic spell-checker is context-awareness. Grammarly understands not just whether a sentence is grammatically correct but whether it is clear, concise, and appropriate for the intended tone. Tone detection tells you how writing is likely to come across emotionally, which is useful for professional emails where the difference between direct and curt genuinely matters.

The free plan covers grammar and spelling checks and is useful for everyday writing. The Pro plan adds full-sentence rewrites, vocabulary enhancement, plagiarism detection, and GrammarlyGO, the generative AI feature that can draft, rewrite, or expand text. At $12/month annually, Pro is competitively priced.

GrammarlyGO, the generative layer, is weaker than dedicated AI writing tools. It produces passable drafts and paraphrases, but the output is mechanical compared to ChatGPT or Claude. Grammarly's strength has always been correcting and polishing existing text, not generating it from scratch. The generative features are a useful bonus, not the primary reason to subscribe.

The Business plan adds shared style guides, brand tone customisation, and analytics for monitoring writing quality across a team. For marketing and customer service teams with strong editorial standards, these features have real value.

Integration breadth is where Grammarly stands out most practically. It works across Chrome, Safari, Firefox, and Edge browsers, in Microsoft Word and Outlook, in Google Docs, in Slack, and in most web text editors. This ubiquity means the tool gets used rather than sitting idle as a separate application.

Privacy deserves attention. The browser extension reads everything typed in a browser, potentially including passwords, private messages, and confidential documents. Review the privacy policy and consider excluding sensitive contexts.