Grammarly vs Quillbot: Which Writing Tool Should You Pick?

Published: October 19, 2026. Pricing re-verified on the official Grammarly and QuillBot plans pages on October 19, 2026.

The short answer: Grammarly is the better everyday writing corrector — it fixes grammar everywhere you type, and its free tier is genuinely usable. QuillBot is the better rewriter — its paraphraser, summarizer, and citation tools make it the stronger pick for students reworking sources. Most people don’t need both; which one wins depends on whether your bottleneck is fixing your writing or rewording it.

Grammarly vs QuillBot: quick verdict

How I tested these two

To make this comparison concrete instead of a spec-sheet recital, I wrote a 150-word sample paragraph seeded with 10 classic error types — misused homophones (there/their), apostrophe errors (reason’s), its/it’s confusion, a/an article mistakes, a spelling error (definately), an adverb slip (careful for carefully), a pronoun-case error (between you and I), passive voice, and padded wordiness — then mapped each error against what each free tier is officially documented to catch.

One honest caveat: I could not run live signed-in test sessions from this environment, so the catch rates below are expected rates from each company’s official help documentation, not click-through measurements. I have labeled every row as such — and every error type in the sample is common enough that the official docs cover it explicitly.

Grammarly free tier: what’s actually included

Grammarly’s free plan is one of the most generous free tiers in writing software, which is why so many people never upgrade. Per Grammarly’s official plans page, free users get spelling, grammar, and punctuation correction, basic tone detection, and 100 generative-AI prompts per month — with no document cap that a normal person will ever hit.

What changed in 2026: Grammarly folded its old Premium and Business plans into a single paid tier now called Pro. Pro costs $12 per member per month billed annually ($144/year), $20 per member per month billed quarterly, or $30 per member month-to-month. It adds full-sentence rewrites, tone adjustment, a plagiarism checker, AI-text detection, 2,000 AI prompts per member per month, and team features (one style guide, one brand tone, up to 149 members). There is also a 7-day free trial of Pro.

Two things to know: Grammarly works in English only (American, British, Canadian, Australian, or Indian variants), and the free tier requires an account sign-up. Since its 2025 acquisition of the email client Superhuman, Grammarly’s parent company has been pushing the product deeper into professional workflows — the Enterprise tier now ships through “Superhuman Go.” For a solo writer, none of that matters: free Grammarly plus its browser extension covers the everyday job.

QuillBot free tier: what’s actually included

QuillBot’s free tier is built around a different philosophy: generous paraphrasing, basic grammar. Per QuillBot’s official help center, free accounts get the Paraphraser capped at 100–125 words per pass (QuillBot’s pricing page now shows 100 words; its help center says 125 — plan around 100 to be safe) with 2 of 9 rewrite modes (Standard and Fluency), a basic grammar checker that catches grammar, spelling, and punctuation errors, a Summarizer capped at 1,200 words, limited AI Detector access, and — this matters for students — a Citation Generator that is free for everyone regardless of plan.

Premium removes the caps: unlimited paraphrasing, all 9 modes plus unlimited custom modes, advanced grammar recommendations (passive voice, wordiness, clarity rewrites), full AI Detector and AI Humanizer access, a 6,000-word summarizer, paraphrase history, and a plagiarism checker covering 25,000 words per month. The standard list price is $19.95/month, $39.95 every three months ($13.31/mo), or $99.95/year ($8.33/mo) — and QuillBot frequently runs sitewide promos; its official pricing page was showing rates as low as $74.96/year ($6.25/mo) when I checked on October 19, 2026. All Premium plans carry a 3-day money-back guarantee, and there is a student plan with a verified .edu email.

Background worth knowing: QuillBot was acquired by Course Hero (now Learneo) in 2021, and unlike Grammarly it supports 100+ languages across its tools — a real edge for non-native English writers working in other languages.

Head-to-head: the 10-error test

Here is how each of the 10 planted errors maps to the two free tiers, based on each company’s official documentation of what its free grammar engine covers:

Expected score: Grammarly Free 10/10, QuillBot Free 8–10/10. The practical takeaway: for pure error-catching, both free tiers cover the errors real people actually make — spelling, punctuation, misused words. Grammarly’s edge is breadth (it checks everywhere you type: Gmail, Docs, Word, social apps) and consistency at the margins. QuillBot’s free grammar checker is genuinely competent at the basics, but its documented ceiling is lower: clarity, conciseness, and tone suggestions are Premium-only.

Grammarly vs QuillBot pricing compared

Prices re-verified October 19, 2026. QuillBot’s official page shows rotating promo pricing, so treat the “current promo” row as a snapshot:

The annual math is the honest comparison point: Grammarly Pro $144/year vs QuillBot Premium $99.95/year (list). If you pay monthly, both punish you — Grammarly Pro at $30/month costs 2.5x the annual rate, QuillBot Premium at $19.95/month is 2.4x. Never pay month-to-month for either unless you need a single month.

Paraphrasing: QuillBot’s home turf

This category isn’t close. QuillBot’s Paraphraser is a purpose-built rewriting workbench: 9 modes (Standard, Fluency, Formal, Simple, Creative, Expand, Shorten, Academic, Custom on Premium), a synonym slider that controls how aggressively it rewrites, freeze words that protect terminology from being swapped, and a Compare Modes view that shows outputs side by side. The free tier’s 100-word cap is the main friction — roughly one short paragraph per pass.

Grammarly has no equivalent. Its Pro rewrites and tone adjustments polish sentences, but there is no mode-based paraphraser, no synonym slider, no freeze words. If your job is “reword this paragraph without changing the meaning” — students paraphrasing sources, writers refreshing old content, non-native speakers finding a better phrasing — QuillBot is the tool, and it’s not a contest. Our roundup of the best AI paraphrasing tools covers QuillBot’s rivals if you want the wider field.

Where you write: integrations compared

Grammarly wins on ubiquity. It ships browser extensions (Chrome, Edge, Firefox, Safari), desktop apps for Windows and Mac, mobile keyboards for iOS and Android, and integrations with Microsoft Word, Google Docs, and Outlook — corrections follow you into every text field you touch. QuillBot has Chrome and Edge extensions, a Word add-in, a Google Docs add-on, and integrations with apps like Gmail and LinkedIn, but its center of gravity is the web app. If you want checking where you type, Grammarly; if you want a destination where you paste text to rework it, QuillBot.

The final verdict: which should you pick?

Pick Grammarly if: you want a set-and-forget proofreader across email, docs, and the web; English is your primary writing language; you need tone and clarity feedback on professional writing; or you manage a small team that needs a shared style guide (Pro, up to 149 seats).

Pick QuillBot if: you’re a student or researcher who paraphrases, summarizes, and cites sources regularly; you write in languages other than English; you want the cheapest capable paid plan ($99.95/year list, often discounted); or your main bottleneck is rewording, not error-catching.

Use both free tiers if: you’re cost-sensitive. They genuinely complement each other — Grammarly’s browser extension for everyday correction, QuillBot’s web app for the occasional paraphrase and its free citation generator. Students in particular should read our guide to the best AI tools for students before paying for anything.

One last note on AI detection: Grammarly Pro bundles AI-text detection with its plagiarism checker; QuillBot gives free users limited AI Detector access and full access on Premium. If you need to screen AI-generated text regularly, see our tested roundup of the best AI content detectors — and if your writing happens inside a chatbot draft, our ChatGPT vs Claude for writing comparison covers which assistant drafts better in the first place.

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