Grammarly and Quillbot are the two most popular AI writing tools for students and professionals — but they do very different things. Choosing the wrong one wastes money and time.
We tested both tools extensively across essay writing, research paraphrasing, grammar checking and professional emails to give you the most honest comparison available in 2026.
⚡ Quick Verdict
Use Grammarly when you are writing your own content and want it to be cleaner, clearer and error-free. Use Quillbot when you are working with existing text and need to paraphrase, summarise or rewrite it. For most students — use both free plans together.
Grammarly
Grammarly
Grammar · Clarity · Plagiarism · Tone
Real-time grammar correction
Clarity and conciseness suggestions
Tone detection and adjustment
Plagiarism checker (premium)
Works in browser, Word, Google Docs
Free plan · Premium $12/month
Quillbot
Quillbot
Paraphrase · Summarise · Citations
7 paraphrasing modes
Summariser for long articles
Auto citation generator
Grammar checker included
Chrome extension and Word add-in
Free plan · Premium $9.95/month
📊 Head-to-Head Comparison
| Feature | Grammarly | Quillbot | Winner |
|---|
| Grammar checking | Excellent | Good | 🟢 Grammarly |
| Paraphrasing | Basic | Excellent — 7 modes | 🟢 Quillbot |
| Summarising | None | Yes — built in | 🟢 Quillbot |
| Plagiarism check | Yes (premium) | Yes (premium) | 🟡 Tie |
| Citation generator | No | Yes — free | 🟢 Quillbot |
| Tone detection | Yes | No | 🟢 Grammarly |
| Works in browser | Yes — everywhere | Yes | 🟡 Tie |
| Free plan quality | Good basics | More features free | 🟢 Quillbot |
| Premium price | $12/month | $9.95/month | 🟢 Quillbot |
| AI writing suggestions | Excellent | Basic | 🟢 Grammarly |
✍️ Grammarly — Deep Dive
What Grammarly does best
Grammarly excels at making your own writing better. As you type it catches grammar errors, suggests clearer phrasing, detects your tone and flags sentences that are too long or confusing. It is genuinely like having an editor looking over your shoulder 24/7.
The premium plan adds a plagiarism checker that scans against 16 billion web pages — essential for university students who need to verify their work before submission. The AI writing suggestions in premium also go beyond grammar into full sentence rewrites.
Where Grammarly falls short is anything involving existing text — it cannot meaningfully paraphrase a paragraph or summarise a long article. It is a writing polish tool, not a content transformation tool.
🔄 Quillbot — Deep Dive
What Quillbot does best
Quillbot is a text transformation tool. Paste in any text and it rewrites it — in 7 different modes ranging from Standard to Creative to Formal. This makes it invaluable for paraphrasing research sources, avoiding self-plagiarism and rewriting content for different audiences.
The free summariser is genuinely impressive — paste in a long research paper and it extracts the key points in seconds. The citation generator supports APA, MLA and Chicago — saving students hours of manual formatting.
Quillbot's grammar checker is solid but not as nuanced as Grammarly's — it catches obvious errors but misses subtle tone and clarity issues that Grammarly would flag.
🎯 Who Should Use Which
Use Grammarly if you:
→ Write essays, reports or emails from scratch
→ Need plagiarism checking before submission
→ Want to improve your writing style over time
→ Write professional content for work
→ Need tone adjustment for different audiences
Use Quillbot if you:
→ Need to paraphrase sources for research papers
→ Want to summarise long articles quickly
→ Need automatic citation generation
→ Want to rewrite content in a different style
→ Are on a tight budget — more free features
🏆 Best combo — use both free plans:
→ Grammarly free for grammar and clarity while writing
→ Quillbot free for paraphrasing and summarising sources
→ Zero cost — covers 90% of student writing needs
❓ FAQs
Can I use both Grammarly and Quillbot together? ▾
Yes — and this is actually the best approach for most students. Use Quillbot to paraphrase your research sources, then run your final draft through Grammarly to polish grammar, clarity and tone. Both have free plans so the combination costs nothing.
Is Quillbot considered cheating at university? ▾
Using Quillbot to paraphrase sources is generally acceptable — it is similar to rewriting a quote in your own words, which students have always done. However, submitting Quillbot-rewritten text as your original analysis or argument may violate academic integrity policies. Always check your university's AI policy and use these tools to assist your thinking, not replace it.
Which is better for non-native English speakers? ▾
Grammarly is significantly better for non-native English speakers. Its real-time suggestions, tone detection and clarity improvements help you write more natural English. Quillbot's paraphrasing can sometimes introduce unnatural phrasing — always review its output carefully.
Does Grammarly detect AI-generated content? ▾
Yes — Grammarly Premium includes an AI detection feature that flags text likely generated by AI tools like ChatGPT. This is useful for teachers and editors, and students should be aware their Grammarly-checked work may also be scanned by their institution's AI detection tools.
✍️ Find More AI Writing Tools
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