Grammarly

Grammarly has evolved from a simple grammar checker into a comprehensive AI writing assistant that embeds itself into virtually every place you write. The browser extension is its killer feature -- once installed, it silently monitors text input across email, documents, social media, Slack messages, and any other text field, providing real-time grammar corrections, clarity suggestions, and tone guidance without requiring you to copy text into a separate tool. This always-on approach means that every email, Slack message, and Google Doc benefits from AI assistance without any change to your workflow. For professionals who write frequently -- and that is most knowledge workers -- this background layer of quality improvement compounds into a meaningful difference over time.

The free tier handles basic grammar and spelling well enough to be genuinely useful, but the Premium tier is where Grammarly becomes a serious writing tool. Full-sentence rewrites, advanced clarity and conciseness suggestions, and plagiarism detection against 16 billion web pages make the $12 per month worthwhile for anyone whose writing quality matters professionally. GrammarlyGO adds generative AI capabilities, allowing you to compose, rewrite, or adjust tone from prompts, though it is notably less capable than dedicated AI assistants like ChatGPT or Claude for longer creative or analytical writing. The Business tier adds brand voice consistency features -- custom style guides, preferred terminology, and tone profiles -- that help teams maintain uniform communication standards.

The limitations of Grammarly are most apparent when compared to general-purpose AI tools. It cannot brainstorm ideas, analyze data, generate code, or engage in the kind of open-ended conversation that makes ChatGPT and Claude so versatile. Its AI writing features feel like an add-on to a correction engine rather than a native generative tool. The style suggestions can also be overly prescriptive, flagging perfectly acceptable stylistic choices as errors if they do not match Grammarly's relatively conservative preferences. English-only support is another constraint for multilingual users. Despite these boundaries, Grammarly occupies a unique and valuable position: it is the best tool available for ensuring that everyday writing -- the kind you do dozens of times a day without thinking -- is consistently clear, correct, and professional.