Editorial note: We use both of these tools on real academic writing before writing about them. Some links on this site may be affiliate links, meaning we can earn a small commission at no extra cost to you — it never changes our verdicts, and both of these tools have free tiers we’ll tell you to try first. Prices were checked in mid-2026 and change often; confirm on each provider’s own page before you pay.
Almost every comparison of these two treats them as rivals, scores them on the same criteria, and crowns a winner. It’s a satisfying format and it produces a slightly useless answer, because Grammarly and QuillBot aren’t really competing. Asking which is better is a bit like asking whether a spellchecker beats a thesaurus. They’re different instruments, and the interesting question isn’t which one wins — it’s when in the writing process each one earns its place.
So rather than a scorecard, we’re going to walk one essay from a blank document to a submitted file, and stop at each stage to say what each tool did, what it couldn’t do, and whether you’d have missed it. Along the way we’ll deal with the thing most articles about QuillBot skip entirely: the fact that its headline feature makes it very easy to cross a line that ends degrees.
The one-sentence version
Grammarly is an editor. It sits in the background wherever you type and catches what’s wrong with the sentences you wrote. QuillBot is a rewriter. It takes a sentence you already have and gives it back in different words. That’s the whole distinction, and almost everything else follows from it.
Which means the honest answer to “which should I get” often turns out to be “the free tier of both, plus neither of them yet.” Bear with us.
Stage 1: The blank page
Here’s the first useful finding, and it surprises people: neither tool helps much here. QuillBot rewrites text, so it needs text to exist first. Grammarly’s free tier includes a small monthly allowance of generative prompts, and its paid tier has more, but neither is really built for “I don’t know what my argument is.”
This stage belongs to a general assistant — a free ChatGPT, Claude or Gemini to think out loud with, or NotebookLM to interrogate your readings. If you’re buying a writing tool to fix a blank page, you’re buying the wrong category of thing entirely. We cover what actually helps here in our guide to AI tools for students.
Stage 2: The messy first draft
You’ve written 800 words and they’re rough. Sentences run on. You’ve used “however” four times. Some paragraphs say the same thing twice.
This is Grammarly’s stage, and its free tier is genuinely good at it. Unlimited grammar, spelling and punctuation checking with no word limit, plus basic tone detection that flags when your draft reads as too casual for an academic paper. In independent testing, Grammarly’s grammar checking — the free feature — consistently catches more errors than QuillBot’s equivalent. If English isn’t your first language, this is the single highest-value free thing on this page: it’s very good at comma rules and tense consistency, which are exactly where non-native writers lose marks they shouldn’t.
What Grammarly free won’t do is rewrite a clumsy sentence for you. It’ll underline it and tell you it’s wordy. Fixing it is your job — which, incidentally, is how you get better at writing.
Stage 3: Drowning in sources
You have six journal articles to work through and no time. QuillBot’s summariser handles texts up to around 1,200 words on the free plan, which is enough for an abstract or a section but not a whole paper. Its free paraphraser caps you at 125 words at a time and gives you two of its nine modes.
Honestly, though, this stage isn’t QuillBot’s strongest showing either. For genuinely understanding a stack of readings, a grounded tool that cites its sources back to the passage does more — and does it free, without a word limit. QuillBot is a rewriting tool that happens to summarise. Use it here if it’s already open; don’t buy it for this.
Stage 4: The paraphrase — and the trap
This is the stage everyone actually comes to QuillBot for, and it’s where we need to be careful, because there are two completely different things happening under the same word.
The legitimate one: you’ve written a paragraph and it’s clunky. You feed it to QuillBot, it hands back three cleaner phrasings, you pick one and edit it. That’s using a tool on your own writing to see how a sentence could sound. It’s the same thing a thesaurus does, and there’s nothing wrong with it. For writers working in a second language, it’s genuinely valuable — it’s how a lot of ESL students find the natural phrasing that was on the tip of their tongue.
The other one: you paste in a paragraph from a source, run it through the paraphraser, and put the result in your essay. That is plagiarism. It doesn’t stop being plagiarism because the words changed. The idea is still someone else’s, uncited, presented as yours — and that’s the definition, not the detection method.
Worth being blunt about: QuillBot is widely, quietly used as a way to get copied text past a plagiarism checker. It often works, which is exactly the problem — it works right up until it doesn’t, and the consequence isn’t a bad mark, it’s an academic misconduct hearing. Universities know this tool exists. Some now use authorship-tracking and AI-detection alongside plagiarism scanning. And the deeper point stands regardless of whether you’re caught: an essay assembled from laundered paragraphs taught you nothing, and you’ll meet the same material again in an exam hall where QuillBot isn’t invited.
Use the paraphraser on your sentences. Cite other people’s. It really is that simple, and the tool is genuinely useful once you’re on the right side of that line.
Stage 5: Revision, the part that actually matters
Your draft is clean but the argument in section three doesn’t land. This is where both tools quietly reveal their ceiling: neither of them thinks. Grammarly will tell you a sentence is wordy; it won’t tell you your evidence doesn’t support your claim. QuillBot will rephrase a weak paragraph into a fluent weak paragraph.
Structural revision is a job for a general assistant that can hold your whole draft and argue with you about it, or better, for a human — a friend, a writing centre, your tutor’s office hours. If you take one thing from this article: the tools in this comparison polish; they don’t diagnose. Students who spend all their time on polish and none on structure are optimising the wrong layer.
Stage 6: The final polish
Back to Grammarly, and this is where the paid tier makes its case if you’re going to make it at all. Grammarly Pro adds full-sentence rewrites, advanced tone and clarity suggestions, a big jump in generative prompts (from around 100 a month on free to roughly 2,000), and unlimited plagiarism checking against a large database — useful for catching your own accidental plagiarism, the half-remembered phrase from a source you read three weeks ago.
QuillBot Premium has a plagiarism checker too, but it’s capped at around 20 pages a month, which for a dissertation is not much. If plagiarism checking is why you’re paying, that gap matters.
Stage 7: Citations
QuillBot’s citation generator is a real perk, supporting the major styles, and it’s part of the package. But we’d point you elsewhere: Zotero does this better, collects sources with one browser click as you read, and is free forever. Building your bibliography as you go beats generating it at 3am. We make that case in our guide to free AI tools for students.
What the free tiers actually give you
| Grammarly Free | QuillBot Free | |
|---|---|---|
| Grammar & spelling | Unlimited, no word cap | Basic suggestions only |
| Rewriting | No full-sentence rewrites | 125 words per paraphrase, 2 of 9 modes |
| Tone detection | Basic, included | No |
| Summarising | No | Up to ~1,200 words |
| Plagiarism check | No | No |
| AI prompts | ~100/month | Co-writer, limited |
| Extensions (Docs, Word) | Yes | Yes, all tiers |
| Credit card to start | No | No, and it doesn’t expire |
Read that table again, because it contains the actual verdict. The two free tiers are almost perfectly complementary: Grammarly free does the thing QuillBot free doesn’t (proper grammar checking, unlimited), and QuillBot free does the thing Grammarly free doesn’t (rewriting, if in small bites). Running both, at zero cost, covers more ground than paying for either one alone.
If you’re going to pay, here’s the maths
QuillBot Premium works out around $8.33 a month on the annual plan, and verified students get roughly $6.25 a month with a school email — a real discount that applies to renewals while you stay verified. Paying month to month costs substantially more, as it usually does. It also has a short money-back window and, unusually, lets you pause your subscription over the summer, which is a nice touch nobody else offers.
Grammarly Pro is around $12 a month billed annually, or roughly $144 a year, and considerably steeper month to month. Grammarly does run a student discount through verification, though the size of it has moved around, so check the current rate on their own page rather than trusting a coupon blog — including this one.
So QuillBot is the cheaper subscription, roughly a third less. But cheaper isn’t the question. The question is what you’re buying, and the answer depends entirely on which stage of the walkthrough above is your bottleneck. If you keep getting marked down for grammar and clumsy sentences, Grammarly Pro is the one that fixes your actual problem. If you write in a second language and constantly need to find a more natural phrasing for your own ideas, QuillBot Premium earns its keep. If you’re not sure, you don’t have a bottleneck yet — use both free tiers for a term and find out.
So which one?
Get Grammarly if you want an always-on editor that catches your mistakes everywhere you write, and especially if English isn’t your first language. Get QuillBot if rewriting your own sentences is the specific job you keep needing done, or if you want the cheaper option and the mode variety. Get both free tiers if you’re a normal student with a normal budget, because together they cover most of it for nothing.
And get neither — yet — if what you actually need is help thinking, structuring or understanding your sources. That’s a different category of tool, and buying a writing assistant to solve it is the most common way students spend money on the wrong thing. The two tools here make finished writing better. They don’t make unfinished thinking finished.
The line, one more time
Everything above assumes you’re using these on your own work. Both companies are clear that their tools are writing aids, and both are widely used in ways their marketing doesn’t advertise. The rules that matter aren’t ours or theirs — they’re your institution’s, and they vary enormously between universities and even between individual lecturers. Some are fine with grammar tools and hostile to paraphrasers; some ask you to declare any AI use. Read your course’s academic-integrity policy before you lean on either for graded work, and if it’s ambiguous, ask. It’s a two-minute email that has saved a lot of people a very bad year.
One practical note on AI detectors, since students ask constantly: they’re unreliable in both directions, they produce false positives on perfectly human writing, and neither of these tools can tell you whether your essay will be flagged. Don’t write to beat a detector. Write your own work, use these tools to make it cleaner, and the question stops mattering.
Frequently asked questions
Is QuillBot or Grammarly better for students?
They do different jobs. Grammarly is the better editor — it catches errors and is stronger at grammar, which is what most students lose marks on. QuillBot is the better rewriter, useful for finding a cleaner way to say your own point, especially for non-native English speakers. For most students, the free tiers of both beat paying for either.
Can I use both together?
Yes, and it’s the most common setup: QuillBot to rework a clumsy sentence of your own, then Grammarly over the finished draft for a final check. Their free tiers are complementary rather than overlapping, so running both costs nothing.
Is using QuillBot cheating?
Using it on your own writing to improve phrasing is normal writing support. Running someone else’s text through it and submitting the result is plagiarism — changing the words doesn’t change whose idea it is. Check your institution’s policy, since some universities treat paraphrasing tools more strictly than grammar checkers.
Which is cheaper?
QuillBot, by roughly a third: about $8.33 a month annually, or around $6.25 with verified student status, against Grammarly Pro’s roughly $12 a month annually. Grammarly also offers a student discount, though the amount has varied — check their current page.
Does Grammarly’s free version actually do anything?
Yes — more than most free tiers. Unlimited grammar, spelling and punctuation checking with no word cap, basic tone detection, and around 100 generative prompts a month. What it withholds is full-sentence rewrites and advanced style suggestions.
The bottom line
QuillBot versus Grammarly was always the wrong fight. Grammarly is the editor you want reading over your shoulder; QuillBot is the rewriter you want when your own sentence won’t come out right. Their free tiers cover different halves of the same job and cost nothing together, which is where most students should start and where plenty should stop. If you do pay, pay for the stage that’s actually costing you marks — and keep the paraphraser pointed firmly at your own words.