Grammarly AI
Writing assistant that checks grammar, tone, and clarity everywhere you type — now with generative AI for rewriting, brainstorming, and drafting. The AI layer on a tool 70 million people already use.
https://grammarly.com↗The Verdict
Grammarly AI is worth it for the grammar, spelling, and tone layer — not for the generative AI features. The AI rewriting is fine but not why you buy Grammarly. You buy it because it works everywhere and catches mistakes before they reach your clients, boss, or customers. A safety net for professional communication.
Claims vs. Findings
What Grammarly AI says vs. what we found after real use.
What they claim
What we found
They claim
Works everywhere — browser extension, desktop app, mobile keyboard, Microsoft Office, Google Docs
We found
The everywhere-you-type integration is genuinely Grammarly's strongest asset. Grammar and spelling corrections appear in Gmail, Slack, Notion, LinkedIn — any text field. No other tool has this breadth of integration.
They claim
Generative AI rewrites, expands, and shortens text in your voice
We found
Generative AI features are adequate but not exceptional. The rewriting tool is useful for shortening wordy emails and adjusting tone. But for actual content generation, Claude and ChatGPT produce better output.
They claim
Tone detection and adjustment for professional communication
We found
Tone detection is surprisingly accurate — it correctly identifies when an email sounds "accusatory" or "passive" and suggests fixes. This is more useful than it sounds for non-native English speakers.
They claim
Brand tone profiles ensure consistent voice across your team
We found
Brand tone profiles work for enforcing basic style guidelines (formal vs casual, British vs American English). Not sophisticated enough for nuanced brand voice but covers the basics.
They claim
Enterprise-grade security with SOC 2 Type II and no training on user data
We found
Enterprise security is a genuine differentiator — SOC 2 Type II, GDPR compliant, no user data used for training. This matters for legal, finance, and healthcare organisations.
The Real Test
Task
We used Grammarly AI across a week of real business communication — 50+ emails, 3 blog post drafts, and 20+ Slack messages — to test both the traditional corrections and the new AI features.
Result
Grammar/spelling corrections were near-perfect — caught 12 genuine errors that would have slipped through. Tone suggestions were useful on 4 emails that sounded more aggressive than intended. The AI rewrite feature was helpful for condensing long emails (average 30% shorter, still clear). Blog post AI suggestions were generic — "make it more engaging" produced filler phrases. The real value is still the grammar and tone layer, not the generative features.
If You Only Use One Feature
Universal writing overlay. The fact that Grammarly works in every text field across every platform — email, Slack, Google Docs, LinkedIn, even web forms — is its moat. No other AI writing tool has achieved this level of integration. You don't have to think about opening it; it's just always there.
Pricing Reality
Free tier catches basic grammar and spelling — genuinely useful but limited. Premium at $12/month adds advanced grammar, tone, and clarity suggestions. Business at $15/user/month adds brand tone, analytics, and admin controls. Enterprise is custom. The generative AI features are included in Premium and above. For individual professionals, Premium is good value — the time saved on proofreading pays for itself. Business pricing is reasonable per-seat.
Who Is This For?
Good fit
Non-native English speakers who need grammar and tone support in professional communication
Teams that send high-volume written communication — sales, support, consulting
Enterprise organisations that need SOC 2-compliant writing assistance
Anyone who writes emails all day and wants a safety net against embarrassing errors
Not the best fit
Creative writers — Grammarly's suggestions push everything toward corporate-neutral prose
People looking for a general AI assistant (use Claude or ChatGPT instead)
Technical writers — Grammarly flags valid jargon and code-related terms as errors
Budget-conscious users who write infrequently — the free tier plus ChatGPT covers most needs
Best Alternative
Claude
For dedicated writing and rewriting tasks, Claude produces better output. But Claude doesn't live in your email client, Slack, and browser — Grammarly's value is being everywhere, not being the best AI writer.
Last updated: 2026-04-12
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