Grammarly is an AI writing assistant that checks your spelling, grammar, punctuation, clarity and tone as you type, in your browser, email, documents and most other apps. Its AI can also draft, rewrite and summarize text, and Pro adds full-sentence rewrites, plagiarism checks and AI-text detection.
This review covers what Grammarly does, who it suits, what each plan costs and how its AI prompt limits work. The short version: Grammarly’s free plan is the best everyday proofreader you can get without paying, and Pro is worth it mainly for people who write for work every day and want whole sentences rewritten, not just fixed.
Cappy’s verdict
| Cappy’s verdict | Grammarly |
|---|---|
| Cappy Score | 4.6/5 |
| Best for | Students, professionals and teams who want clean, clear writing everywhere they type |
| Price | Free plan; Pro $12/member/month (annual) or $30 monthly |
| Standout feature | Real-time suggestions in almost every app and website |
| Biggest catch | Full rewrites, plagiarism checks and most AI prompts need Pro, and monthly billing is expensive |
Grammarly is our top pick among AI writing tools. Start with the free plan, and move to Pro on annual billing only if you write for work most days and want rewrites and plagiarism checks.
What is Grammarly?
Grammarly is a writing assistant that works where you already write. Once you install the browser extension, desktop app or mobile keyboard, it underlines mistakes and unclear sentences and suggests fixes you can accept with one click. It works in Gmail, Google Docs, Microsoft Word, Slack, LinkedIn and, by the company’s count, more than 500,000 apps and websites.
On top of corrections, Grammarly includes generative AI. You can ask it to draft an email, shorten a paragraph, change the tone or reply to a message, using a limited number of AI prompts each month.
In late 2025, Grammarly’s parent company renamed itself Superhuman, after buying the Superhuman email app and the Coda docs tool. Grammarly is still sold under its own name, but the company’s larger plans now come as part of a Superhuman bundle.
Who is Grammarly best for?
- Students who want clean essays and assignments without paying anything.
- Professionals who send emails, reports and messages all day and want them to sound clear and confident.
- Non-native English writers who want help with grammar, word choice and natural phrasing.
- Teams that want consistent writing, with a shared style guide and brand tones on Pro.
- Content writers who want a final polish and a plagiarism check before publishing.
Grammarly is a weaker fit if you mainly need to paraphrase or summarize long passages, which QuillBot does better and cheaper, or if you want an AI to write long articles from scratch, where a general assistant like ChatGPT is a better starting point. Its checks are also strongest in English.
Key features of Grammarly
Real-time grammar, spelling and punctuation checks
This is Grammarly’s core job, and it’s included on the free plan. As you type, it flags spelling mistakes, missing commas, wrong word forms and grammar errors, with a short explanation of each fix. Because the same checker follows you across apps, you get consistent corrections in email, documents and chat.
Clarity and tone
Grammarly flags wordy or confusing sentences and shows how your writing is likely to come across, such as confident, friendly or formal. The free plan detects tone; Pro adds suggestions to adjust it and rewrite whole sentences for clarity.
Generative AI prompts
You can highlight text and ask Grammarly to shorten it, make it more formal or turn notes into an email, or write a reply from scratch. Each request uses one AI prompt: 100 a month on Free and 2,000 per member a month on Pro.
Plagiarism and AI-text detection
Pro checks your text against web pages and academic papers and points out passages that match existing sources. It also includes an AI detector that estimates whether text looks AI-generated. Both are useful before you submit an assignment or publish, but no detector is fully reliable, so treat the results as a guide.
Grammarly docs and AI agents
Grammarly also has its own AI writing editor, called docs, with specialist agents built in. They include an AI Grader that gives rubric-based feedback and an estimated grade, a Citation Finder for supporting evidence and formatted citations, Reader Reactions to predict how your audience will respond, a Proofreader, a Paraphraser and the AI and plagiarism checkers.
One agent, Expert Review, has been removed. It gave feedback in the style of well-known writers, and Grammarly took it down after criticism and a lawsuit over using people’s names and work without their consent.
Style guides and brand tones for teams
Pro teams can set a shared style guide, such as preferred spellings, product names and banned phrases, and brand tones that Grammarly checks against as everyone writes. Pro supports up to 149 members.
How Grammarly works day to day
You sign up with an email or Google account, then install the browser extension, the Mac or Windows app, or the mobile keyboard. Setup takes a few minutes. You choose your English dialect (such as US, UK or Indian English) and your writing goals, such as audience and formality.
After that, Grammarly runs in the background. Underlines appear as you type: red for correctness, blue for clarity and others for tone and style. Click one to see the suggestion and accept or dismiss it. When you need more, select text and open the AI menu to rewrite, shorten or change the tone.
Most people end up accepting quick fixes without thinking about them and using AI prompts a few times a day, for a tricky email or a paragraph that doesn’t flow.
Grammarly pricing
Grammarly has a free plan, Pro at $12 per member per month on annual billing, and Enterprise at a custom price. Pro costs $30 a month on monthly billing, and a quarterly option works out to about $20 a month. A 7-day free trial of Pro is offered on the pricing page.
| Plan | Monthly billing | Annual billing (per month) | AI prompts | What you get |
|---|---|---|---|---|
| Free | $0 | $0 | 100 a month | Grammar, spelling and punctuation, tone detection |
| Pro | $30 per member | $12 per member ($144/year) | 2,000 per member a month | Full-sentence rewrites, tone adjustment, plagiarism and AI detection, style guide and brand tones, up to 149 members |
| Enterprise | Custom | Custom | Unlimited | SSO, advanced security and admin controls, sold through Superhuman |
What does the Grammarly free plan include?
The free plan includes unlimited grammar, spelling and punctuation checks, tone detection and 100 AI prompts a month, across the browser extension, desktop apps and mobile keyboard. No credit card is needed. For many students and casual writers, that’s all they’ll ever need.
What it doesn’t include: full-sentence rewrites for clarity, tone adjustments, plagiarism checks, AI detection and the larger prompt allowance.
How do Grammarly AI prompts work?
Each time you ask Grammarly’s AI to write, rewrite or reply, it uses one prompt. Normal grammar and spelling suggestions don’t use prompts. On Pro, the 2,000 prompts are counted per member, so each person on a team has their own allowance. Prompts reset every month and don’t roll over.
How much does annual billing save?
A lot. Pro costs $144 a year on annual billing, compared with $360 for 12 months on monthly billing, a saving of $216 or 60%. If you’re sure you’ll use Grammarly for a year, annual is by far the better deal. If you’re not, use the free trial or pay monthly for one month first.
Which Grammarly plan should you choose?
- Students and casual writers → Free
- Writing for work every day, or need plagiarism checks → Pro on annual billing
- A team that needs shared style rules → Pro, one seat per writer
- A large company with security reviews → Enterprise
What Grammarly costs for different users
| Situation | Best plan | Cost per year |
|---|---|---|
| A student proofreading essays | Free | $0 |
| A freelancer writing for clients | Pro (annual) | $144 |
| A professional who wants to try Pro first | Pro (monthly, then switch) | $30 for the first month |
| A team of 5 with a shared style guide | Pro (annual), 5 seats | $720 |
| A team of 20 | Pro (annual), 20 seats | $2,880 |
Is Grammarly safe and private?
Grammarly reads the text you write in order to check it, which is how any writing assistant works. The company says it doesn’t sell user data, and you can turn Grammarly off for specific websites and apps in its settings.
Be careful with confidential material. If you handle sensitive client, legal or medical documents, check your employer’s policy first; many companies approve only Enterprise accounts with admin controls. You can also switch Grammarly off in apps where you write confidential text.
Common Grammarly problems and how to fix them
- Suggestions don’t appear in an app. Check that the extension or desktop app is turned on for that site or app, and update it. Some apps block extensions.
- It “corrects” words you use on purpose. Add them to your personal dictionary, or set the right English dialect in your account.
- You ran out of AI prompts. The free plan has 100 a month. Save prompts for rewrites you can’t do yourself, or upgrade to Pro for 2,000.
- You were charged $30 instead of $12. The $12 price is the monthly equivalent of the $144 annual plan. Monthly billing costs $30. Switch to annual in your account settings.
- The plagiarism check flags your own sources. Quoted passages with citations will still show as matches. Check each one rather than rewriting everything.
- The AI detector marks your own writing as AI. No detector is fully reliable. Keep drafts and notes as proof of your work if your school or client uses detectors.
Grammarly pros and cons
What we like
- The free plan is the best free proofreader available
- Works in almost every app and website you write in
- Clear explanations help you learn from your mistakes
- Pro adds rewrites, plagiarism checks and AI detection in one plan
- Style guides and brand tones help teams sound consistent
What could be better
- Monthly billing costs $30, more than double the annual rate
- Full rewrites and plagiarism checks need Pro
- 100 AI prompts a month on Free runs out quickly for heavy users
- Paraphrasing and summarizing are weaker than QuillBot’s
- Checks are strongest in English
Grammarly alternatives
The best Grammarly alternatives are QuillBot, Wordtune, Rytr and Jasper. QuillBot is the closest match and costs less; the others are better at writing new drafts than at fixing yours.
| Tool | Best for | Free plan | Paid plans from |
|---|---|---|---|
| QuillBot | Paraphrasing and summarizing | Yes, paraphrasing up to 125 words at a time | $8.33/month (annual) |
| Wordtune | Rewriting sentences in different ways | Yes, 10 rewrites a day | $4.89/month (annual) |
| Rytr | Cheap short-form drafts | Yes, 10,000 characters a month | $7.50/month (annual) |
| Jasper | Marketing teams producing content at scale | No, 7-day free trial | $59/seat/month (annual) |
Quick pick:
- Want clean, correct writing everywhere → Grammarly
- Want to reword or summarize text → QuillBot
- Want several rewrites of each sentence → Wordtune
- Want cheap AI drafts for short content → Rytr
- Want a marketing content platform → Jasper
For a side-by-side look, read Grammarly vs QuillBot, our guide to the best AI writing tools, our Rytr review, or browse all AI writing tools.
Is Grammarly worth it?
Grammarly Free is worth it for almost everyone who writes in English. It costs nothing, takes minutes to install and catches mistakes everywhere you type.
Grammarly Pro is worth it if writing is a big part of your job: client emails, reports, proposals or published content. At $144 a year on annual billing, the rewrites, tone adjustments and plagiarism checks pay off quickly. Skip Pro if you only write occasionally, and avoid monthly billing unless you need it for a single month.
How to get the most out of Grammarly
- Set your goals per document. Tell Grammarly the audience and formality, and its tone suggestions get more useful.
- Pick the right English. Choose US, UK, Canadian, Australian or Indian English so spellings aren’t flagged wrongly.
- Build your dictionary. Add names, product terms and industry words so they stop getting flagged.
- Save AI prompts for hard parts. Use quick fixes for small errors, and prompts for paragraphs you’d struggle to rewrite.
- Run the plagiarism check before you submit, and check each match yourself rather than rewriting blindly.
- Turn it off where it doesn’t belong, such as code editors or confidential documents.
Frequently asked questions
Is Grammarly free?
Yes. Grammarly’s free plan includes unlimited grammar, spelling and punctuation checks, tone detection and 100 AI prompts a month, with no credit card needed. Rewrites, plagiarism checks and more prompts need Pro.
How much does Grammarly Pro cost?
Pro costs $12 per member per month on annual billing, which is $144 a year. Monthly billing costs $30 a month. Enterprise is priced on request.
Is Grammarly Pro worth it?
If you write for work most days, yes. Pro adds full-sentence rewrites, tone adjustments, plagiarism and AI detection, and 2,000 AI prompts a month. Casual writers usually do fine on the free plan.
Does Grammarly have a free trial?
Grammarly’s pricing page offers a 7-day free trial of Pro. You can also use the free plan for as long as you like.
Is Grammarly the same as Superhuman now?
Grammarly’s parent company renamed itself Superhuman in late 2025. Grammarly is still sold as its own product, with Free and Pro plans, while Enterprise is sold through the Superhuman bundle.
Does Grammarly detect AI writing?
Grammarly Pro includes an AI detector that estimates whether text looks AI-generated. Like all AI detectors, it can be wrong, so don’t treat its score as proof either way.
Is Grammarly better than QuillBot?
For correcting and polishing writing in every app, yes. QuillBot is better and cheaper for paraphrasing and summarizing. Our Grammarly vs QuillBot comparison covers the details.
Does Grammarly work in Google Docs and Microsoft Word?
Yes. Grammarly works in Google Docs through the browser extension and in Microsoft Word through its add-in and desktop app, as well as in Gmail, Outlook, Slack and most websites.