Grammarly is one of the oldest names in AI writing help. It started as a grammar checker and now offers rewriting, tone adjustment, and a set of AI agents. What sets it apart is reach: browser extensions, desktop apps, and mobile keyboards mean it works in your email, your documents, and almost any text box on the web.
The free plan handles spelling, grammar, and punctuation. Pro adds full-sentence rewrites, tone controls, and far more generative prompts, with team and enterprise tiers above that. Prices and plan contents shift, so check Grammarly's plans page.
What it does well
For routine writing, such as a client email, a report, or a cover letter, Grammarly is fast and unobtrusive. It catches the small mistakes that undermine a message and suggests clearer phrasing without asking you to switch apps.
The tone suggestions are genuinely useful when you are not sure whether a message reads as too blunt or too stiff, and recent agents can flag text that sounds machine-written or estimate how a reader might react. For a non-native English speaker, simply having a second pair of eyes before hitting send prevents a lot of small misunderstandings. It is less help for long, structural edits, where you still have to reorganise the argument yourself.
How to use it without losing your voice
Accept the corrections, but treat style and rewrite suggestions as options, not orders. If you take every one, prose tends to become bland and uniform. Read the sentence aloud with and without the change and keep the version that sounds like you. For a stronger edit, ask it to explain why a change helps. Set the audience and formality once, and the suggestions get noticeably more relevant.
What to watch
Grammarly is not a fact-checker; it will happily polish a wrong claim. Its AI detector, like all of them, gives probabilities rather than proof, so do not use it to accuse anyone.
If you write mainly in Chinese, support is limited because the tool is built around English. For a tool focused purely on sharpening sentences, compare DeepL Write; for rephrasing and summarizing, see QuillBot.
