Grammarly review: Still the default for clean writing, even as AI eats the territory

The first time Grammarly caught something embarrassing for us was an email to a CEO where we'd written "your welcome." Five seconds before send. After about six years and tens of thousands of small saves like that, Grammarly is the kind of tool that has paid back the subscription many times over by catching things we'd never notice ourselves.

The interesting question now isn't whether Grammarly is good at what it does -- it is -- but whether what it does still matters as much when ChatGPT, Claude, and Apple Intelligence will all happily rewrite our terrible draft into something publishable. We've stayed subscribed for another year. Here's why, and where the cracks are showing.

The grammar engine remains best in class

Grammarly's core spell-and-grammar engine is the most reliable we use. It catches things spellcheck doesn't (their/there/they're in context, dangling modifiers, comma splices, tense agreement across long sentences), and it does this on a stream of typing without slowing the editor down. The false-positive rate is genuinely low, which is the thing that matters: tools that flag too many "issues" stop getting trusted, and Grammarly almost never flags things that aren't actually wrong.

After 14+ years of iteration on this specific problem, the engine has the kind of accuracy that's hard to replicate with a general-purpose LLM. We've tested asking Claude and ChatGPT to "find typos and grammar errors in this email." They catch most things Grammarly catches, but they also catch things that aren't errors, and they occasionally invent corrections that change meaning. Grammarly's narrower scope is the source of its reliability.

The browser integration is the real wedge

The most underrated feature isn't a feature, it's a posture. Grammarly works in every text field on the web by default: email, Slack, Google Docs, Notion, the comment box on LinkedIn, an admin form in your CRM. That ambient presence is what makes the rest of the product matter, because you're not deciding to use Grammarly. It's just there when you type.

ChatGPT's "rewrite my draft" loop is more powerful per use but worse per quarter. You have to copy into ChatGPT, prompt, copy out. Grammarly underlines an issue in place and you press Tab to accept. The cognitive overhead per fix is approximately zero.

The AI features arrived late and feel bolted on

In 2023 and 2024 Grammarly added generative AI on top of its existing product: "Improve clarity," "rewrite this sentence," "make it more confident." The features work fine, but they don't feel like Grammarly figured out what it specifically wanted to do with AI. They feel like Grammarly noticed everyone else was doing AI and added it.

The output quality is fine. It's not noticeably better than asking ChatGPT or Claude the same thing. And in most cases, if you've already opened a browser tab to ChatGPT for the harder rewrites, you don't reach for the Grammarly button for the easier ones.

Premium is harder to justify than it used to be

Free Grammarly catches the things that get you fired (your/you're, blatant typos, basic agreement). Premium adds tone suggestions, vocabulary upgrades, plagiarism checking, and the generative AI rewrites. At $12 a month on annual, this is more than half the price of ChatGPT Plus ($20), and ChatGPT Plus does more.

For students writing papers, the plagiarism check alone justifies Premium. For professionals writing emails and docs, the case is weaker than it was two years ago. We've kept Premium because the always-on tone suggestions have measurably improved how cold outreach lands. But if we were re-evaluating today, we'd think harder about it.

The corporate angle still works

Grammarly Business adds team analytics, style-guide enforcement, and central management. For organizations where consistency of voice matters (legal, customer success, marketing) this tier is the actual differentiator. ChatGPT doesn't enforce your brand's style guide across 80 employees' Slack and email threads. Grammarly does.

Privacy on Business is handled differently than consumer: your text isn't used for model training by default, retention is configurable, SSO and SCIM are standard. For regulated industries this is the version that gets through procurement.

Where it still wins

Two things Grammarly does that nothing else does as well. First, it catches real errors with a false-positive rate low enough that you actually trust the underlines, on a stream of typing, without slowing you down. Second, it improves writing you've already written without rewriting your voice.

That second one is subtle. ChatGPT and Claude will happily rewrite your draft, but the result often sounds like ChatGPT or Claude. Grammarly suggests changes that preserve your voice -- fix the typo, tighten the sentence, soften the tone, without rewriting the thing.

Should you use it?

Yes for the free tier. The grammar engine alone is worth the install, and the browser integration means you'll use it without thinking about it.

Premium is a closer call than it was. If you write a lot for work and the tone suggestions are useful, keep it. If you're already paying for ChatGPT Plus and use it for rewrites, you can probably skip Premium without missing much.

Grammarly is in the awkward position of being excellent at what it was built for, while what it was built for becomes a smaller slice of what people actually need. The product isn't going anywhere; the room it occupies is shrinking around it.