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Short answer
Use Grammarly for proofreading as you type. Use ChatGPT for rewriting and restructuring. Grammarly works inside your email, documents and browser, flags mistakes in real time and keeps your original wording. ChatGPT is better at bigger changes: shortening a draft, changing tone, restructuring an argument or rewriting a weak paragraph. If you write a lot for your business, using both (free Grammarly + ChatGPT) covers almost everything.
| Grammarly | ChatGPT | |
|---|---|---|
| Best for | Catching errors as you type | Rewriting, tone and structure |
| Works where | Browser, Gmail, Docs, Word, desktop apps | Chat window (plus apps/extensions) |
| Keeps your wording | Yes, suggests specific fixes | Often rewrites more than you asked |
| Explains mistakes | Yes | Yes, if asked |
| Free plan | Yes (core grammar and spelling) | Yes |
| Paid | Pro per month | Plus per month |
Try Grammarly free (affiliate link)
Grammar accuracy
In general, both catch most spelling and grammar errors. ChatGPT tends to fix everything at once and rewrite sentences you didn't want changed, so you can't easily see what was wrong. Grammarly shows each change individually so you stay in control.
ChatGPT proofreading prompt that avoids over-editing:
> Proofread the text below. Fix only spelling, grammar and punctuation errors. Don't change wording, tone or structure. Then list every change you made as "original → corrected (reason)". Text: paste
Tone and rewriting
This is ChatGPT's strength. It can:
- Make an email friendlier, firmer or more concise
- Turn a rambling paragraph into three clear bullets
- Rewrite for a different audience ("explain this to a non-technical customer")
- Suggest stronger headlines and openings
Grammarly's paid plans include tone detection, full-sentence rewrites and generative AI features, which are good for quick polish but less flexible than a conversation with ChatGPT.
Winner: ChatGPT.
Workflow integration
Grammarly wins here. It works where you write: Gmail, Google Docs, Word, LinkedIn, your CMS and most browser text boxes. Mistakes are underlined as you type.
ChatGPT means copying text in and pasting it back out, although desktop apps and integrations reduce that friction.
For quick, frequent writing (emails, social posts, messages) Grammarly saves more time. For important pieces (a sales page, a proposal, a blog post), a ChatGPT editing pass is worth the copy-and-paste.
Winner: Grammarly.
Pricing
| Plan | Price | What you get |
|---|---|---|
| Grammarly Free | Free | Spelling, grammar, punctuation, limited AI prompts |
| Grammarly Pro | See site | Clarity rewrites, tone, plagiarism check, more AI prompts |
| ChatGPT Free | Free | Proofreading and rewriting with usage limits |
| ChatGPT Plus | See site | Higher limits, better models, projects, many other uses |
ChatGPT Plus does far more than editing, so if you already pay for it, you may only need Grammarly's free plan.
Should you use both?
For most small business owners, yes, and it can cost nothing:
- Grammarly Free running in the background catches typos everywhere you write.
- ChatGPT (free or Plus) for rewriting, tone changes and editing longer pieces.
- Final read-through by a human. Neither tool knows your customers or your facts.
Upgrade to Grammarly Pro only if you write a lot of client-facing material and want rewrites and tone checks without leaving the page.
Our recommendation
| You... | Use |
|---|---|
| Mostly write emails and short messages | Grammarly Free |
| Write blog posts, sales pages and proposals | ChatGPT + Grammarly Free |
| Write in English as a second language | Grammarly Pro (explanations and fluency suggestions help a lot) |
| Already pay for ChatGPT Plus | Add Grammarly Free, skip Pro |
| Want one tool on a budget | ChatGPT Free with the proofreading prompt above |
More writing tools: see our best AI writing tools for small business and 50 ChatGPT prompts for small business.
Free: get 50 ChatGPT prompts for your business, sent straight to your inbox. Get the free prompts ()
FAQ
Is Grammarly still worth it with ChatGPT?
The free version is, because it catches errors as you type everywhere you write. The paid version is worth it mainly for people who write a lot of client-facing content or write in a second language.
Is ChatGPT good at grammar?
Yes, it's very good at spotting and fixing grammar errors. The risk is that it changes more than you asked. Use a prompt that limits it to corrections and asks for a list of changes.
Can ChatGPT replace Grammarly?
For editing finished drafts, largely yes. For real-time checking while you type in email and documents, Grammarly is more convenient.
Does Grammarly use AI?
Yes. Grammarly uses AI for its suggestions and includes generative AI features for rewriting and drafting.
Is it safe to paste business documents into these tools?
Check each tool's privacy settings and business plans before pasting confidential information, and avoid pasting sensitive customer data.
