Last updated: 2026-08-19
Founded in 2009, Grammarly is an AI writing assistant that checks grammar, spelling, punctuation, tone, and clarity as you type, built on rule-based checks for its Free tier and transformer models for Pro-level rewrites. It plugs directly into Gmail, Google Docs, Microsoft Word, Slack, and other everyday writing surfaces.
About Grammarly
Grammarly launched in 2009 in Ukraine as a browser-based grammar checker and has grown into a communication platform, backed by $545M in equity funding plus a $1B revenue-based financing round in May 2025. The Free tier runs on rule-based and statistical checks, while Pro and Enterprise use transformer models for tone, clarity, and generative rewriting. It plugs into more than 1 million apps and websites, including Gmail, Microsoft Word, Slack, Google Docs, and Zendesk. Free, Pro, and Enterprise tiers cover individuals, teams, and large organizations that want consistent writing across every surface.
Pricing
Pro runs $12/month billed annually (or $30/month billed monthly) and unlocks full-sentence rewrites, tone adjustment, 2,000 monthly AI prompts, plagiarism detection, and advanced vocabulary suggestions. Enterprise pricing is custom (contact sales), with unlimited AI prompts and admin controls. Annual billing saves up to 60% versus paying monthly. Free covers basic grammar, spelling, and punctuation checks with no time limit.
Key Features
- Real-Time Grammar & Spelling Checks: Instantly catches and corrects grammar, spelling, and punctuation errors as you type across all platforms
- Tone Detection & Adjustment: Analyzes writing tone and suggests adjustments to strike the right register for your audience (formal, casual, confident, etc.)
- Generative AI Assistance: Generates text, rewrites full sentences, creates outlines, and drafts content from scratch, with monthly AI-prompt allowances that scale from Free up to Enterprise
- Plagiarism Detection: Scans content against billions of web pages and academic sources to flag plagiarism and ensure originality
- Brand Voice & Style Guides: Customize style rules, upload company style guides, and apply consistent brand tone across team communications
- Smart Drafts and Tone Rewriter: 2026 Smart Drafts generate full content from short prompts with built-in grammar and clarity checks; Tone Rewriter instantly pivots writing between confident, diplomatic, or enthusiastic styles without changing core content.
Pros
- Wide integration reach across the apps people already write in, including Gmail, Word, Slack, and Docs, removes the need to switch tools mid-task
- Real-time feedback catches errors instantly and improves writing quality with minimal friction
- The Free tier provides solid foundational grammar and spelling checks with no hidden costs
- Enterprise-grade security certifications (SOC 2, ISO 27001/27017/27018) and GDPR compliance protect user data for regulated teams
- Generative AI features enable content generation, rewriting, and tone adjustment without needing a separate tool
Cons
- No offline mode: every feature needs an internet connection to work
- Suggestions are not always contextually accurate; the AI can misfire on nuance-dependent or creative writing
- The feature gap between Free and Pro is large, and upgrade prompts can feel aggressive
- Language support beyond English is limited despite Grammarly's multilingual expansion claims
- Plagiarism and AI-detection results are not always accurate, which can mislead students and professionals who rely on them
Data Handling
- Compliance
- SOC 2 Type I · SOC 2 Type II · SOC 3 · ISO 27001 · ISO 27017 · ISO 27018 · HIPAA-compliant · GDPR-compliant
Frequently Asked Questions
What are Grammarly's pricing plans in 2026?
Free is $0 forever for basic grammar and spelling checks. Pro is $12 a month on the annual plan, or $30 billed monthly, and unlocks tone rewrites, plagiarism detection, and thousands of monthly AI prompts. Enterprise is quote-based through sales.
What do you get on Grammarly's free tier?
The Free plan covers grammar, spelling, and punctuation checks across every supported app, with generative rewrites capped at 100 AI prompts a month. Tone adjustment, full-sentence rewrites, and plagiarism detection all sit behind Pro or Enterprise.
What should you use instead of Grammarly?
QuillBot leans harder into paraphrasing and AI detection, with paid plans up to $99.95. ProWritingAid adds deeper style-editing reports for long-form writers, priced up to $699. Wordtune focuses on AI21-powered sentence rewrites rather than full grammar coverage, with paid plans up to $15.99.
What separates Grammarly from QuillBot?
Grammarly is the broader of the two, correcting grammar, spelling, and tone across 1 million+ integrated apps. QuillBot puts its weight behind paraphrasing, with several rewrite modes and a separate AI-detection tool. The split follows the job: consistent writing help inside email and chat, or reworking a draft you already have.
How do you set up Grammarly?
Grammarly runs as a browser extension, a desktop app for Windows and Mac, and a mobile keyboard for iOS and Android, all free to install from grammarly.com. Once added, it activates automatically inside apps like Gmail, Word, Slack, and Docs, so there is no separate document upload step. Moving to Pro or Enterprise just means upgrading the plan from the same account.
Top Alternatives
- QuillBot: Daily grammar and tone correction inside the apps you already use points to Grammarly; paraphrasing or an AI-detection check points to QuillBot.
- ProWritingAid: Grammarly reaches more apps than anything else in this category, while ProWritingAid goes deeper on style reports for long manuscripts.
- Wordtune: Full grammar and spelling coverage is Grammarly's job. Wordtune is the narrower buy when all you want is AI21-powered sentence rewriting.
HokAI guides covering Grammarly
- Best AI Writing Assistant in 2026: How to Actually Choose: Grammarly, Wordtune, QuillBot and 6 more AI writing assistants compared for 2026, with the criteria to use once you stop trusting the shortlist alone.
- Copy.ai vs JetWriter AI in 2026: They're Not Actually Competing: Fullcast bought Copy.ai in October 2025 and cut its free tier for $1,000-a-month GTM pricing. JetWriter AI stayed an $18 extension. See who each fits.
- Best AI for University Assignments in 2026: The best AI for university assignments isn't one chatbot: QuillBot, Humata AI, NotebookLM, ChatGPT and Grammarly each cover a different stage, priced for 2026.
- Best AI Assistant for Small Business in 2026: Six AI assistants worth paying for in 2026: Microsoft Copilot, Lindy, Timeless, MagicForm, HyperWrite and Grammarly, priced from each vendor's own pricing page.
- Verify Any AI Tool's Pricing in Four Minutes: The HokAI Checklist: Five checks any buyer can run on a vendor's own pricing page in about four minutes to catch stale figures. Demonstrated live on Jasper, checked August 27, 2026.