Grammarly

What it does

Grammarly catches grammar, spelling, punctuation, and clarity issues across virtually every platform you write on. The browser extension works in Gmail, Google Docs, Slack, LinkedIn, and most web-based text fields. The desktop app covers native applications on macOS and Windows. The mobile keyboard handles phone-based writing. This ubiquity is Grammarly's core strength — it becomes a passive safety net for all your written communication without requiring you to change your workflow. The grammar corrections are reliable and fast, catching errors that spell check alone misses. The tone detection feature analyzes your text and flags when your writing might come across as too direct, too casual, or too formal for the context, which is genuinely useful for professional emails and sensitive communications.

Who it's for

Grammarly serves three audiences particularly well: professionals who write frequently and want a quality check before sending, students writing papers and assignments, and non-native English speakers who want confidence that their writing reads naturally. The free tier handles basic grammar and spelling and is worth installing for that alone. Premium at $12/mo adds the features that make the tool more genuinely useful — full sentence rewrites for clarity, word choice suggestions, plagiarism detection, and tone adjustment controls. The Business tier at $15/mo per member adds style guides and brand tone enforcement, which matters for teams that need consistency across multiple writers. Creative writers may find Grammarly frustrating — it tends to push prose toward conventional business English and will flag intentional stylistic choices as errors.

AI generation versus core editing

Grammarly has added AI text generation features to compete with tools like ChatGPT and Jasper, but these are the weakest part of the product. The generated text is competent but generic, lacking the personality and specificity that dedicated AI writing tools can produce with the right prompting. Where Grammarly excels is not generating text but improving text you have already written. The clarity rewrites in Premium genuinely tighten wordy sentences and simplify unnecessarily complex phrasing. The difference between using Grammarly for what it is good at — editing and polishing — versus what it is adding to stay competitive — content generation — is significant. Stick to the editing features and you will get consistent value.

The bottom line

Grammarly is the most broadly useful writing tool available because it works where you already write, catches real errors, and requires almost no effort to use. The free tier is strong enough to be valuable on its own, and Premium at $12/mo is a reasonable upgrade for anyone who writes professionally. The tone detection and clarity rewrite features justify the cost for most users. The AI generation features are not a reason to subscribe — if you need AI-generated content, use a dedicated tool for that. Grammarly's value is in making your own writing cleaner, clearer, and more appropriate for your audience. For that specific job, it remains the default recommendation.