In this article
The short answer
Grammarly and LexiLint solve different problems. Grammarly assists you while you write — inline suggestions in Gmail, Google Docs, Slack, and more. LexiLint checks pages after they're written — any URL you can open in Chrome, including your live website, staging environment, or localhost.
If you write in Google Docs and want real-time grammar suggestions, use Grammarly. If you publish content and want to catch errors on the finished page — without sending that text to any third-party server — use LexiLint.
Many people use both.
What each tool actually does
🔍 LexiLint
- Scans any webpage on demand
- Works on live sites, localhost, staging
- Spell check: 100% offline, instant
- Grammar: AI via your own API key
- Highlights errors directly on the page
- Custom dictionary for brand/tech terms
- 8 languages (Premium)
- MCP server for AI coding tools
✏️ Grammarly
- Real-time suggestions as you type
- Works in Gmail, Docs, Slack, etc.
- Spell and grammar in one pass
- Tone and clarity suggestions
- Plagiarism detection (Premium)
- Style consistency checks
- Business team features
- Native apps for Mac and Windows
The key distinction: Grammarly sits inside your writing apps. LexiLint sits on top of any webpage. One is a writing companion; the other is a publishing proofreader.
Privacy and data handling
This is where the two tools differ most sharply.
How Grammarly handles your text
Grammarly processes text on its cloud servers. When the extension is active and you type in a supported app, your text is transmitted to Grammarly for analysis. This is how the product works — the AI suggestions are generated server-side. Grammarly's privacy policy describes what is collected and how it is used.
How LexiLint handles your text
Spell check: Dictionaries are bundled inside the extension. Spell checking runs entirely on your device — no network requests, zero data sent anywhere. You can disconnect from the internet and it still works.
Grammar check: LexiLint uses BYOK (Bring Your Own Key). You configure your own API key from Google Gemini, OpenAI, or Anthropic. When you run a grammar check, your browser sends the text directly to your chosen provider. LexiLint's servers receive nothing.
Privacy verdict: For users handling sensitive text — client work, legal documents, internal content — LexiLint's architecture offers a meaningful difference. Nothing passes through a third-party server you didn't choose.
Pricing
LexiLint
- Free: Spell check forever (offline). AI grammar with your own Google Gemini key — Gemini's free tier covers most daily usage.
- Premium: Adds 6 more languages (Spanish, French, German, Polish, Russian, Turkish) and multi-provider support (OpenAI, Claude).
For most users, LexiLint is effectively free forever. The Gemini free tier is generous enough that you'll rarely hit limits.
Grammarly
- Free: Basic grammar and spell check. Limited suggestions.
- Premium: ~$12/month (billed annually). Full grammar, style, tone, clarity, and plagiarism.
- Business: ~$15/user/month. Team features, style guides, analytics.
Grammarly's free tier is useful but limited. Meaningful use requires Premium.
Full feature comparison
| Feature | LexiLint | Grammarly |
|---|---|---|
| Checks published webpages | ✓ | ✗ |
| Works on localhost & staging | ✓ | ✗ |
| Real-time typing suggestions | ✗ | ✓ |
| Works in Gmail / Google Docs / Slack | ✗ | ✓ |
| Offline spell check | ✓ 100% offline | ✗ |
| BYOK — choose your AI provider | ✓ Gemini, OpenAI, Claude | ✗ Grammarly's AI only |
| Text sent to third-party servers | Spell: never. Grammar: your provider only | ⚠ Grammarly's cloud |
| Data collection | Zero without consent | ⚠ Yes |
| Custom dictionary | ✓ | ✓ |
| Multi-language support | ✓ 8 languages (Premium) | ✓ Many languages |
| Tone & clarity suggestions | ✗ | ✓ Premium |
| Plagiarism detection | ✗ | ✓ Premium |
| MCP server for AI tools | ✓ Claude Desktop, Cursor | ✗ |
| Free for daily use | ✓ Spell check + Gemini free tier | ⚠ Limited free tier |
| Native desktop app | ✗ | ✓ Mac, Windows |
Who should use which
Grammarly You write long-form content in Google Docs or Word
Grammarly's real-time suggestions are genuinely useful here. You get feedback as you write, not after.
LexiLint You publish to a website, blog, or CMS
Once your post is live, Grammarly can't see it. LexiLint opens the page in Chrome and checks it directly — catching errors that slipped through the drafting stage.
Grammarly You want inline suggestions in Slack and email
Grammarly's browser extension integrates directly into communication apps. LexiLint doesn't.
LexiLint You work with sensitive content and can't use cloud tools
Legal, financial, medical, or client-confidential text. LexiLint's spell check never leaves your device. Grammar check goes to an AI provider you control, using your own key.
LexiLint You develop websites and need to check localhost or staging
LexiLint works on any URL Chrome can load. Grammarly won't activate on local development URLs.
LexiLint You use Claude Desktop, Cursor, or other AI coding tools
LexiLint has an MCP server — spell and grammar checking available directly in your AI tools without consuming tokens for spell check.
LexiLint in AI tools (MCP)
This is something Grammarly doesn't have: a Model Context Protocol (MCP) server for spell and grammar checking inside AI coding assistants.
What this means in practice
When you ask Claude Desktop or Cursor to check spelling, the AI normally processes your text using tokens — costing you money per check. With LexiLint MCP, spell checking runs locally via spell_check. Zero tokens consumed. Zero API calls. Instant.
Grammar checking still uses AI — but via your own key, not the assistant's budget.
For developers who use AI tools daily and pay per token, this is a meaningful difference. A 500-word spell check via Claude or GPT costs roughly $0.02. With LexiLint MCP it costs nothing.
LexiLint MCP is listed in the official MCP registry and works with Claude Desktop, Cursor, and any MCP-compatible tool.
Verdict
These aren't competing products in the traditional sense. They target different moments in the writing process.
Grammarly is a writing assistant. It helps you as you draft — real-time, contextual, integrated into the apps where you write.
LexiLint is a publishing proofreader. It checks the finished page — any URL, including pages no other grammar tool can reach. With no data collection for spell check and BYOK for grammar, it's built for people who care where their words go.
Use Grammarly while drafting in email, docs, and chat. Use LexiLint to check the published result — especially if privacy matters or you work on pages Grammarly can't access.
Your words matter. So does where they end up.
Free spell check forever · Free AI grammar with Gemini key · No subscription required