Overview
Whether you're a student polishing an essay, a professional drafting reports, or a content creator publishing daily, choosing the right writing assistant can meaningfully improve the quality and speed of your work. Two of the most popular tools on the market are Grammarly and QuillBot — but they were built with different goals in mind.
Grammarly, founded in 2009, is primarily a grammar, spelling, and style checker. With over 30 million daily active users, it has become the go-to tool for catching errors and improving the clarity of your writing. Its deep integration with browsers, word processors, and email clients makes it a seamless layer on top of wherever you already write.
QuillBot, founded in 2017, took a different angle. Instead of focusing solely on correctness, QuillBot excels at paraphrasing, summarizing, and rewriting text. It's particularly popular among students and researchers who need to rephrase ideas, condense long documents, or avoid unintentional plagiarism.
Both tools have grown significantly in recent years, adding features that overlap with each other. So which one should you choose? Let's break it down.
Features Comparison
| Feature | Grammarly | QuillBot |
|---|---|---|
| Grammar check | Excellent | Basic |
| Plagiarism check | Premium only | Premium only |
| Paraphrasing | Limited (GrammarlyGO) | Core feature (7 modes) |
| Tone detection | Yes | Limited |
| Browser extension | Yes (Chrome, Edge, Safari, Firefox) | Yes (Chrome, Edge) |
| Word processor integration | Google Docs, Word | Google Docs, Word |
| AI writing assistant | GrammarlyGO | AI Essay Writer |
| Summarizer | No | Yes |
| Citation generator | No | Yes |
| Vocabulary enhancer | Yes (suggestions) | Yes (synonym wheel) |
Pricing Comparison
Grammarly
| Plan | Price | Key Features |
|---|---|---|
| Free | $0/month | Basic grammar, spelling, punctuation checks |
| Premium | $12/month (billed annually) | Full grammar suite, tone detection, GrammarlyGO |
| Business | $15/month per member | Team features, style guides, analytics dashboard |
QuillBot
| Plan | Price | Key Features |
|---|---|---|
| Free | $0/month | Paraphraser (3 modes), summarizer, 125-word limit |
| Premium | $9.95/month or $4.17/month (billed annually) | All 7 paraphrase modes, unlimited words, plagiarism checker, AI essay writer |
QuillBot is notably more affordable, especially on an annual plan. At $4.17/month billed annually, it's one of the most cost-effective writing tools available — making it a natural fit for students on tight budgets.
Grammarly: Pros and Cons
Pros
- Best-in-class grammar and style checking — catches nuanced issues like passive voice overuse, comma splices, and wordiness
- Works everywhere — the browser extension covers Gmail, LinkedIn, Google Docs, Slack, and virtually any text field
- Tone detector helps you communicate with the right voice for your audience
- Detailed explanations for each correction help you learn as you write
- 30M+ users means constant model improvements and a well-tested product
Cons
- Expensive for full functionality — $12/month for Premium is steep if you only need basic grammar help
- Paraphrasing is limited — GrammarlyGO rewrites are useful but not as specialized as QuillBot's dedicated paraphrasing modes
- No summarizer — you can't condense long documents inside Grammarly
- No citation generator — academic users need to look elsewhere for citations
- Can be overly aggressive — sometimes flags stylistic choices as errors
QuillBot: Pros and Cons
Pros
- Superior paraphrasing with 7 distinct modes (Standard, Fluency, Formal, Academic, Simple, Creative, Expand, Shorten)
- Built-in summarizer handles long articles, research papers, and PDFs
- Citation generator supports APA, MLA, Chicago, and more — invaluable for students
- Very affordable especially on the annual plan at $4.17/month
- Plagiarism checker included with Premium
Cons
- Grammar checking is minimal — not a replacement for Grammarly's error detection
- Browser extension limited to Chrome and Edge (no Firefox or Safari)
- Free plan is restrictive — 125-word limit on the paraphraser significantly limits casual use
- Tone and style guidance is weak compared to Grammarly
- Newer and less polished overall UX compared to Grammarly's mature interface
Use Cases
Choose Grammarly if you:
- Write professionally and need consistent, error-free output
- Work across many platforms and want a tool that follows you everywhere
- Want to improve your writing skills over time through explanations
- Need tone and clarity guidance for business or marketing content
- Are a non-native English speaker focused on correctness
Choose QuillBot if you:
- Are a student who regularly paraphrases, summarizes, or cites sources
- Need to rewrite content in different styles or registers
- Want a budget-friendly writing tool for academic work
- Work with long documents that need to be condensed
- Need to generate citations in multiple academic formats
Use both if you:
- Do a mix of professional writing and academic research
- Want the best grammar correction (Grammarly) plus the best paraphrasing (QuillBot)
- The two tools are complementary and many power users subscribe to both
Version History
Grammarly has evolved significantly since its 2009 launch. Early versions focused purely on grammar correction for students. By 2015, Grammarly had released its browser extension, dramatically expanding its reach. The introduction of the tone detector in 2019 and GrammarlyGO (its AI writing assistant powered by generative AI) in 2023 marked its shift toward a full writing platform.
QuillBot launched in 2017 with a single paraphrasing tool. It quickly added a summarizer, grammar checker, and plagiarism detector. In 2022, QuillBot was acquired by Course Hero, giving it resources to accelerate development. The AI Essay Writer and expanded citation generator were added in 2023–2024, pushing QuillBot further into the academic writing space.
Verdict
Grammarly is the better choice for most professionals and everyday writers. Its grammar engine is unmatched, its integrations are seamless, and its interface is polished after 15+ years of development.
QuillBot is the better choice for students and academic writers. Its paraphrasing, summarizing, and citation tools are genuinely best-in-class, and its pricing is hard to beat — especially on the annual plan.
If budget is a constraint, QuillBot's free plan is more functional than Grammarly's for paraphrasing work, while Grammarly's free plan wins for grammar correction. For maximum impact, consider using both: Grammarly for writing and editing, QuillBot for research and rewriting.