Short answer: choose Grammarly if you want mistakes fixed as you type in Gmail, Word, Google Docs or your browser. Choose ChatGPT if you want help brainstorming, researching or writing a draft from a blank page. If you write often, using both is the best set-up: draft in ChatGPT, then polish in Grammarly.
That is the quick verdict. The rest of this guide explains why, with prices, limits, privacy rules and a simple way to decide. Prices and features were checked on 5 November 2026, so always confirm them at checkout.
Grammarly vs ChatGPT at a Glance
These two tools are not exact rivals. Grammarly is an editing assistant that sits inside the apps you already use. ChatGPT is a general-purpose AI assistant where you type a request and get an answer. Writing is only one of the things ChatGPT does.
| Feature | Grammarly | ChatGPT |
|---|---|---|
| Main job | Real-time editing and proofreading | Chat-based drafting, research and analysis |
| Grammar and spelling | Built in, highlights errors as you type | Only when you ask in a prompt |
| Writing from scratch | Limited, plan-based AI prompts | Strong |
| Tone adjustment | Pro and Enterprise | Through prompts |
| Plagiarism checker | Pro and Enterprise | Not listed on the official pricing page |
| AI-text detector | Pro and Enterprise | Not listed on the official pricing page |
| Research and summaries | Not a core feature | Search, deep research and file analysis (by plan) |
| Free plan | Yes, 100 AI prompts a month | Yes, unlimited everyday text chats under fair-use guardrails |
| Best for | Polishing text you have already written | Creating and shaping ideas and drafts |
Which One Should You Use for Your Writing Task?
| If you want to… | Better choice | Why |
|---|---|---|
| Fix typos and grammar while typing | Grammarly | Works inside your apps, no copy and paste |
| Write a first draft or outline | ChatGPT | Built for open-ended drafting |
| Make an email sound more polite | Grammarly | One-click tone suggestions |
| Summarise a long report | ChatGPT | File uploads and large context windows |
| Check text for plagiarism | Grammarly Pro | Built-in checker |
| Brainstorm ideas | ChatGPT | Back-and-forth conversation |
| Translate or write in other languages | ChatGPT | Flexible multilingual chat |
| Keep a team’s writing consistent | Grammarly | Style guides and brand tone controls |
What Is Grammarly?
Grammarly is an AI writing assistant that checks spelling, grammar, punctuation, clarity and tone. It works through browser extensions (Chrome, Firefox, Edge and Safari), Windows and Mac desktop apps, mobile keyboards, Google Docs and Microsoft Word. It also supports Gmail, Outlook, Slack and Teams.
Paid plans add full-sentence rewrites, tone changes, plagiarism checking and AI-text detection. Grammarly also supports regional English, including British and Indian English, so your spelling suggestions match your audience.
Grammarly plans
- Free: basic corrections and 100 AI prompts a month.
- Pro: 2,000 AI prompts per member a month, rewrites, tone control, plagiarism and AI detection. Pro has replaced the old Premium name.
- Enterprise: unlimited prompts, admin controls and custom pricing.
- Education: an institutional licence sold to schools and universities.
What Is ChatGPT?
ChatGPT is OpenAI’s AI assistant, launched in November 2022. You type instructions and it can draft, rewrite, summarise, translate, explain and research. Writing is one use among many, alongside coding, data work and file analysis. If you are curious about how widely this kind of tool is used, our guide on how many people use Character AI shows how fast conversational AI has grown.
ChatGPT plans
- Free: unlimited everyday text chats under fair-use guardrails, with limited tools.
- Go: a low-cost tier, reported at around $8 a month in some regions.
- Plus: $20 a month, with advanced models, projects, custom GPTs and more usage.
- Pro: from $100 a month, with the highest limits and larger context windows.
- Business, Enterprise and Edu: for teams and institutions. Business starts at two users.
Model names change quickly, so check OpenAI’s pricing page before you subscribe.
The Key Difference: Editing Layer vs Writing Workspace
Grammarly improves text that already exists. It watches over your shoulder and flags problems without being asked. ChatGPT waits for a prompt, then produces or rewrites text. That leads to two practical differences:
- Workflow: Grammarly needs no copying and pasting. ChatGPT usually does.
- Control: Grammarly makes small, targeted fixes. ChatGPT can change a whole passage, which is useful but means you must check that your meaning and facts are intact.
Feature Comparison
Grammar, spelling and punctuation
Grammarly wins on convenience. It underlines errors as you type and lets you accept a fix with one click. ChatGPT can correct grammar well, but only after you paste text and ask. For quick daily writing, such as emails and messages, Grammarly saves time.
Tone, clarity and rewriting
Grammarly shows how your writing may sound and suggests changes. With ChatGPT you describe the tone yourself, for example “make this firm but polite”. ChatGPT gives more control, Grammarly gives more speed. Tone is a tie, depending on how you like to work.
Drafting and content generation
ChatGPT is the stronger choice for first drafts, outlines and long-form content. Grammarly can generate text too, but its AI prompts are capped by plan: 100 a month on Free and 2,000 on Pro. If you create marketing copy, our piece on B2B marketing for technology companies is a good example of content where ChatGPT can help with the outline and Grammarly with the final polish.
Research and summaries
ChatGPT offers search, deep research and file analysis, depending on your plan. Grammarly is not built for research. Whichever you use, check every fact and source yourself, as AI tools can state wrong information with confidence.
Plagiarism and AI-text detection
Grammarly Pro and Enterprise include a plagiarism checker and an AI-text detector. ChatGPT’s official pricing page lists neither. Treat both results as a guide, not proof. Independent evidence on how reliable AI detectors are was not confirmed in our research, so never use a detector score on its own to accuse someone.
Languages
Grammarly is strongest in English, including US, UK, Canadian, Australian and Indian variants, and offers support in more than 20 languages. ChatGPT is more flexible for translation and writing across many languages through conversation.
Long documents
ChatGPT publishes its limits. The chart below shows the total context window for its “Instant” model by plan, which decides how much text it can handle in one conversation. Grammarly does not publish a numeric document limit.
As a rough guide, OpenAI estimates about 12 pages of input on Free, about 40 on Go and Plus, and about 250 on Pro for the Instant model.
Integrations and Ease of Use
| Platform | Grammarly | ChatGPT |
|---|---|---|
| Chrome, Firefox, Edge, Safari | Yes, extensions | Web app (extension support not confirmed) |
| Windows and Mac | Desktop apps | Desktop access by plan |
| Android and iOS | Keyboard and apps | Apps |
| Google Docs | Yes | Not confirmed (Google Sheets extension listed) |
| Microsoft Word | Yes | Word extension, by plan |
| Email and chat apps | Gmail, Outlook, Apple Mail, Slack, Teams | Not a native email tool |
Grammarly is easier for people who simply want to type and be corrected. ChatGPT is easier for people who prefer to explain what they want in plain sentences.
Grammarly vs ChatGPT Pricing
Prices below are US list prices before tax. Both companies show local currencies in some regions, and taxes such as VAT or GST may be added at checkout, so the final price for readers in the UK or India can differ.
| Plan | Price (USD) | Billing | Key limit |
|---|---|---|---|
| Grammarly Free | $0 | None | 100 AI prompts a month |
| Grammarly Pro | $12 per member a month | Annual ($144 a year) | 2,000 AI prompts a month |
| Grammarly Pro | $30 per member a month | Monthly | 2,000 AI prompts a month |
| Grammarly Pro | $60 per member | Quarterly | 2,000 AI prompts a month |
| Grammarly Enterprise | Custom quote | Contact sales | Unlimited prompts |
| ChatGPT Free | $0 | None | Limited tools and uploads |
| ChatGPT Go | About $8 (varies by region) | Monthly | More usage than Free |
| ChatGPT Plus | $20 | Monthly | Advanced models, projects, custom GPTs |
| ChatGPT Pro | From $100 | Monthly | Highest limits, API credits |
| ChatGPT Business | Roughly $20 to $25 per user | Monthly or annual | Minimum two users |
What you pay over a year
Using both tools costs $384 a year at these prices. Roughly 63% of that goes to ChatGPT Plus and 37% to Grammarly Pro.
Is it worth paying?
- Grammarly Pro is worth it if you write daily, want tone help, or need plagiarism and AI-text checks.
- ChatGPT Plus is worth it if you brainstorm, research, summarise files or draft long pieces.
- Stick to the free plans if you write only now and then. Try both before paying.
Compare like with like: Free with Free, and paid with paid. Grammarly Pro and ChatGPT Plus cost similar amounts but do different jobs. If you are weighing up other subscription tools too, see how we compare paid software in SE Ranking vs Moz.
Privacy and Data Training
Both companies let you opt out of having your text used to improve their models, but the defaults are not the same for every plan.
| Question | Grammarly | ChatGPT |
|---|---|---|
| Training on personal plans | May use samples unless you opt out (Product Improvement and Training setting) | May use content unless you turn off “Improve the model for everyone” |
| Business plans | Enterprise and Education plans have training off by default, with extra controls | Business and Enterprise data is not used for training by default |
| Temporary option | Not confirmed | Temporary Chat is not used for training |
| Where data is stored | US-based AWS data centres | Global infrastructure, which may include the US |
| Catch to know | Editor documents are kept until you delete them | Giving feedback on a reply can lead to that chat being used for training |
Practical advice: do not paste confidential contracts, client data or personal details into a free account. For work documents, use a business plan and follow your employer’s policy. Users in the UK and EU are covered by the UK GDPR and EU GDPR, and users in India by the Digital Personal Data Protection Act, so check each company’s privacy page for how it handles your rights.
For Students: What Is Safe to Do?
Rules differ by school and university, so read your institution’s AI policy first. In general:
- Using Grammarly to fix grammar and clarity in your own writing is usually the easier case to justify.
- Submitting text written by ChatGPT as your own work is often banned. Ask first, and declare any AI use if required.
- Neither tool can guarantee you will pass an originality or AI check, and detectors are not proof of who wrote something.
- Verify every source and citation. AI tools can invent references.
Best Choice by Type of User
| User | Start with | Reason |
|---|---|---|
| Student | Grammarly Free, ChatGPT only if allowed | Fixing your own writing is safer than generating it |
| Non-native English speaker | Both | Grammarly corrects as you type; ChatGPT explains why |
| Blogger or freelancer | Both | ChatGPT for outlines, Grammarly for the final edit |
| Marketer | Both | Ideas from ChatGPT, brand tone from Grammarly |
| Business team | Business or Enterprise plans | Better privacy defaults and admin controls |
| Casual user | Free plans | Both have a useful free tier |
If you also write social posts, a tool like our Snapchat caption generator can give quick ideas, while Grammarly keeps the final wording clean.
How to Use Grammarly and ChatGPT Together
- Brainstorm and outline in ChatGPT.
- Write or generate a first draft.
- Check facts and sources yourself.
- Paste the draft into Grammarly, or write in Google Docs or Word with Grammarly switched on.
- Review grammar, clarity and tone, and accept or reject each suggestion.
- Do a final read-through and, if needed, a plagiarism check.
Do the human check last. Neither tool knows your audience or your facts as well as you do.
Pros and Cons
| Pros | Cons | |
|---|---|---|
| Grammarly | Works where you type; fast fixes; tone help; plagiarism and AI-text checks on Pro | Weak at research and long drafting; AI prompts are capped; best features need a paid plan |
| ChatGPT | Flexible drafting; research and file analysis; explains its edits; handles many languages | Needs prompts and pasting; no built-in plagiarism or AI-text checker; may change facts or add errors |
Alternatives Worth a Look
- QuillBot: focused on paraphrasing.
- ProWritingAid: deeper style and writing reports.
- LanguageTool: grammar checking across many languages.
- Claude and Gemini: general AI assistants similar to ChatGPT.
- Microsoft Editor: built into the Microsoft ecosystem.
We have not compared these in detail here, so check their current plans before choosing.
Final Verdict
- Choose Grammarly if you mostly edit and send emails, documents or essays and want errors fixed in the apps you already use.
- Choose ChatGPT if you start from a blank page, research a lot or need a flexible assistant for more than writing.
- Choose both if writing is part of your job and you can justify around $384 a year, or use the free plans of each.
Start with the free plans, test them on your own writing for a week, and upgrade only the one you actually miss. If you track tool demand for your business, our look at CRM demand shows how software adoption trends can guide your choices.
Frequently Asked Questions
Is ChatGPT better than Grammarly?
It depends on the task. ChatGPT is better for drafting, brainstorming and research. Grammarly is better for real-time proofreading, tone and plagiarism checks.
Can ChatGPT replace Grammarly?
Partly. ChatGPT can fix grammar when you ask, but it does not check your writing automatically across Gmail, Word and your browser, and it has no listed plagiarism or AI-text detector.
Which is better for grammar?
Grammarly, because it is built for grammar and flags mistakes as you type.
Can I use Grammarly and ChatGPT together?
Yes. Draft or brainstorm in ChatGPT, then edit in Grammarly. Check facts and follow any school or workplace rules.
Does Grammarly check plagiarism?
Yes, on Pro and Enterprise plans. It is not included on the Free plan.
Can ChatGPT detect AI-written text?
ChatGPT’s official pricing page does not list a native AI-text detector. Grammarly lists one on Pro and Enterprise, but no detector is proof of authorship.
Which is cheaper?
Both have free plans. For paid plans, Grammarly Pro billed annually ($144 a year) costs less than ChatGPT Plus ($240 a year), but billed monthly Grammarly Pro ($360 a year) costs more.
Does ChatGPT train on my text?
On personal plans it may, unless you turn off “Improve the model for everyone” in Data Controls. Business and Enterprise data is not used for training by default.
Is Grammarly safe for confidential documents?
Grammarly describes encryption and access controls, but for sensitive work you should use an Enterprise plan, review the privacy settings and follow your employer’s policy.
Does Grammarly work in Google Docs and Word?
Yes, Grammarly supports both, along with Gmail, Outlook and major browsers.
Last checked: 5 November 2026. Prices, limits and model names change often, so confirm them on the official Grammarly plans page and ChatGPT pricing page before you buy.