Grammarly Review: The Writing Assistant Everyone Uses But Nobody Loves

You’ve almost certainly used Grammarly. Thirty million people have the browser extension installed, and it’s become so ubiquitous that red underlines on bad grammar feel as natural as spellcheck in Word. But here’s the question nobody asks: is the paid version actually worth it, or are you just paying for peace of mind?

I’ve been using Grammarly Free for years and Grammarly Premium for the past three months. Here’s what I found.

What Grammarly Actually Does

At its core, Grammarly is a writing checker. It catches spelling errors, grammar mistakes, and punctuation problems in real time as you type — in Gmail, Google Docs, Slack, and basically anywhere you write in a browser. The desktop app also works in native macOS and Windows apps.

That’s the free tier. The paid tiers add AI-powered rewriting, tone detection, full-sentence rewrites, plagiarism checking, and what Grammarly calls “AI agents” that can draft content from prompts.

Three tiers exist:

• Free — grammar, spelling, punctuation, 100 AI prompts/month
• Premium — everything in Free plus full-sentence rewrites, tone suggestions, fluency, plagiarism checker, 1,000 AI prompts/month
• Business — Premium features plus style guides, brand tones, centralized billing, analytics dashboard

The key thing people miss: Grammarly isn’t just the underlines. It’s now a generative AI tool too. You can highlight text and ask it to rewrite, shorten, expand, or change the tone. You can generate entire drafts from prompts. It’s trying to be both the safety net and the writing engine.

The Free Tier: Better Than You Think

Here’s something I genuinely didn’t expect — Grammarly Free is still one of the best free tools on the internet. It catches real mistakes that matter. Not style nitpicks, actual errors: missing articles, subject-verb disagreement, comma splices.

I tested it by writing a batch of deliberately flawed emails. Grammarly Free caught about 85% of real grammar and spelling errors. The remaining 15% were edge cases like split infinitives and Oxford comma disagreements that honestly don’t matter for most people.

The 100 AI prompts per month on the free tier is new and generous. That’s enough for casual use — rewriting the occasional email, brainstorming a headline, tightening a paragraph. You won’t write a book with 100 prompts, but for a solopreneur sending 20 emails a week? Plenty.

If you’re a solopreneur on a tight budget, stop here. The free tier covers 80% of what you actually need.

Premium: The $12/Month Question

Premium costs $12/month when billed annually ($144/year) or $30/month if you go month-to-month. That annual price sounds reasonable until you realize it’s $144/year for what is essentially a better grammar checker with AI features bolted on.

Let me break down what Premium actually adds:

Full-sentence rewrites are the headline feature. Click on a highlighted sentence, and Grammarly suggests alternative phrasings. Sometimes they’re genuinely better. Often they’re just… different. I’d estimate about 40% of rewrite suggestions actually improved my writing. The rest were neutral or made things worse by stripping out personality.

Tone detection tells you how your writing sounds — formal, friendly, confident, concerned. It’s interesting for about a week, then you stop checking it. If you already know how tone works, this is a novelty. If you’re genuinely unsure whether your email sounds too aggressive, it’s useful.

The plagiarism checker works. I tested it against known sources, and it correctly identified copied passages down to 15+ word matches. If you’re writing academic content or hiring freelancers who might plagiarize, this alone could justify the cost. For most solopreneurs? You probably don’t need it.

1,000 AI prompts per month is the real upgrade from free’s 100. If you’re using Grammarly’s generative features regularly — drafting responses, rewriting product descriptions, generating meeting follow-ups — you’ll burn through 100 prompts in a week. The 1,000 cap on Premium is comfortable for daily use.

Fluency suggestions help non-native English speakers more than native ones. They catch awkward phrasing that’s grammatically correct but reads unnaturally. If English isn’t your first language, this feature alone might be worth the Premium price.

The AI Features: Impressive But Not Irreplaceable

Grammarly’s generative AI has improved significantly. You can highlight text and get rewrites, or type a prompt and get a draft. The AI understands context better than it did a year ago — it won’t just rearrange your words, it’ll actually restructure ideas.

I tested the “Generate” feature by asking it to draft a client follow-up email. The result was… fine. Professional, polite, appropriately concise. It was a solid B+ email. The problem is that ChatGPT or Claude would produce the same B+ email in about the same time, and you’re already paying for one of those.

The rewriting feature is better than generation. Highlighting a clunky paragraph and asking Grammarly to tighten it usually produces good results. The AI respects your voice better than a general-purpose LLM with a “rewrite this” prompt. That’s Grammarly’s real advantage — it knows the surrounding context of what you’re writing because it’s embedded in your document.

But here’s my honest take: I found myself reaching for Grammarly’s AI features about twice a week. The rest of the time, I was using it exactly like I used the free tier — watching for red underlines on typos. If you already have a ChatGPT or Claude subscription, Grammarly’s AI features overlap significantly with what you can do there.

Browser Extension: The Unsung Hero

The thing nobody talks about is how frictionless Grammarly’s browser extension is. It just works. No copy-pasting into a separate app. No “open Grammarly to check this.” The corrections appear inline, everywhere you type.

This is actually Grammarly’s biggest moat. Writing assistants like ProWritingAid or LanguageTool are arguably better at specific things, but none of them integrate as seamlessly across as many platforms. Grammarly works in Gmail, Google Docs, Slack, Notion, Twitter, LinkedIn, and hundreds of other sites without any setup.

For a solopreneur who writes across 10 different tools every day, that universality matters. You don’t want to copy every email into a separate checker. You want corrections where you already are.

What Annoyed Me

The upselling is aggressive. Grammarly Free bombards you with Premium upgrade prompts. Every time it catches something that’s “Premium only,” there’s a popup. The free experience is deliberately hamstrung to make you feel like you’re missing out. It’s a common SaaS tactic, but Grammarly does it more annoyingly than most.

The desktop app is a resource hog. Grammarly’s desktop app consumed about 400MB of RAM on my Mac and occasionally caused typing lag in certain apps. The browser extension is lighter, but if you use the desktop app for native apps like Notes or Bear, expect some performance impact.

Privacy concerns are real. Grammarly reads everything you type. Every email, every document, every Slack message. Grammarly says they don’t sell your data, but they do use it to improve their models. For solopreneurs handling client information, contracts, or sensitive business data, this is worth thinking about. You can exclude specific sites, but the default is “everything.”

The AI sometimes strips personality. Grammarly’s rewrites tend toward corporate blandness. My writing voice is intentionally informal — contractions, sentence fragments, the occasional rhetorical question. Grammarly’s AI suggestions often try to smooth all of that into beige professionalism. If you care about voice and style, you’ll reject more suggestions than you accept.

Pricing Breakdown

Plan	Monthly Price	Annual Price	AI Prompts	Key Features
Free	$0	$0	100/month	Grammar, spelling, punctuation
Premium	$30/mo	$12/mo ($144/yr)	1,000/month	Full rewrites, tone, plagiarism, fluency
Business	$25/member/mo	$15/member/mo ($180/yr/member)	2,000/member/month	Style guides, brand tones, analytics
Enterprise	Custom	Custom	Custom	SAML SSO, custom AI, data loss prevention

The month-to-month Premium at $30 is highway robbery. Never pay monthly — the annual plan at $12/month is the only sensible option. If you’re unsure, use the free tier until you’re confident Premium adds value for your workflow.

One hidden cost: Grammarly charges per seat on Business plans. A three-person team costs $540/year minimum. If you’re a solopreneur who occasionally collaborates with freelancers, the Premium individual plan is the better deal.

Who Should Use Grammarly

Non-native English speakers writing in English professionally. Grammarly Premium’s fluency and clarity features will improve your writing noticeably, and the inline corrections teach you in real time. This is genuinely one of the best investments for ESL solopreneurs.

Anyone who writes a high volume of emails. If you send 15+ emails daily and accuracy matters (sales, consulting, client communication), Grammarly Free at minimum saves you from embarrassing typos. Premium catches the subtler mistakes that erode credibility.

Content writers and bloggers who want a second pair of eyes on everything they publish. The plagiarism checker is useful if you work with freelancers or aggregate content from multiple sources.

Who Should Skip It

Strong writers who already use AI chatbots. If your grammar is solid and you already have a ChatGPT or Claude subscription, Grammarly’s AI features largely duplicate what you can do there. Save the $144/year.

Privacy-conscious professionals. If the idea of an AI reading every keystroke makes you uncomfortable — especially for sensitive client work — you’re better off with manual proofreading or periodic passes through an offline tool.

Anyone writing primarily outside browsers. Grammarly’s best feature is its browser integration. If you mostly write in VS Code, Obsidian, or other desktop editors that Grammarly doesn’t support well, the value drops significantly.

The Verdict

Grammarly is a utility player, not a star. It’s the writing equivalent of a good spellchecker — you don’t think about it much, but you’d notice if it disappeared. The free tier is genuinely excellent and enough for most solopreneurs. Premium is worth it if you’re a non-native speaker, write massive volumes, or genuinely use the AI features daily. Otherwise, it’s $144/year for marginally better suggestions than free.

I actually went back to the free tier after my Premium trial ended, and honestly? I barely noticed the difference in my daily workflow. The red underlines catch the stuff that matters. Everything else is nice-to-have.

Ease of Use: 9/10 — It works everywhere, needs zero setup, and the inline corrections are genuinely seamless. One point off for occasional desktop app lag.

Value for Money: 6/10 — The free tier is a 9/10 value. Premium at $144/year is fair but not compelling unless you use every feature. Month-to-month at $30 is a bad deal.

Solopreneur Fit: 7/10 — Universally useful, but most solopreneurs will be perfectly happy with the free tier. Premium shines for ESL writers and high-volume communicators.

Overall: 7.5/10 — Grammarly remains the default writing assistant for good reason. The browser extension alone justifies keeping it installed. Just don’t feel pressured into Premium unless you’ve hit specific limitations with the free tier.