Acadly AI vs QuillBot: Paraphrase, Grammar and AI Detection in One Place

QuillBot has been the default paraphraser for close to a decade. It is the tool most students open first when a sentence sounds wrong. It is also, as of April 2026, charging $19.95/mo for Premium — twice what Acadly AI Pro costs — while offering a narrower feature set. This is the honest breakdown.

QuillBot pricing

QuillBot Free caps paraphrase at 125 words per run and 500 words per summarizer run. You get 3 synonym levels, 2 writing modes, and limited grammar checks. QuillBot Premium ($19.95/mo on monthly, cheaper on annual) removes the 125-word cap and unlocks the remaining modes (Standard, Fluency, Formal, Academic, Simple, Creative, Expand, Shorten), plus full grammar, plagiarism detection, and their AI content detector. Premium includes Word and Chrome integrations.

Acadly AI pricing

Acadly AI Pro is $17.99/mo on monthly, $11.92/mo on annual (save 70%). Paraphrase runs up to 800 words in a single pass — over six times QuillBot Free's cap. All eight rewrite modes are included (Standard, Academic, Formal, Simple, Creative, Shorten, Expand, Fluency). Grammar Checker, AI Detector, and Humanizer ship in the same dashboard. Free users get 10 paraphrase runs, 10 grammar runs, 5 humanizer runs, 5 detector runs, and 3 plagiarism runs per month, with 800 words per paraphrase pass — still higher than QuillBot Free's 125-word cap.

QuillBot vs Acadly AI at a glance

The real feature gap

QuillBot is a text-polishing stack. You bring a paragraph, it hands back a better paragraph. That is an entirely legitimate product — the rewrite quality is good and the Word plugin is well-built. What it is not, is a research workflow. If you are writing a paper, QuillBot cannot scaffold the abstract for you, cannot build the figure that goes with your results, cannot produce the slides that go into your defense, and cannot answer questions grounded in the 20 PDFs on your desktop.

Acadly does all of that in the same dashboard. The paraphraser lives next to the Research Writer, which lives next to Document Chat, which lives next to Slides. A sentence rewritten in Paraphrase and pasted into a Research Writer draft is tracked in the same Generation History. Nothing gets lost in the copy-paste seam between tools.

Free-tier honesty

QuillBot Free's 125-word paraphrase cap is the tool's most-discussed limitation. It forces students into the premium tier after about two paragraphs of serious work. Acadly's Free tier gives you 10 paraphrase runs per month with a much higher per-run cap, which is enough to get a full assignment through without paying. The trade-off on Free is the total number of runs, not the per-run word count.

QuillBot Premium vs Acadly AI Pro

The price argument is simple enough: $17.99 vs $19.95 is roughly 10% cheaper for a dramatically broader feature surface. The workflow argument is the more important one. If your writing pipeline ends at 'rewrite the paragraph,' QuillBot's depth in that one corner is fine. If your pipeline runs from 'draft the abstract' to 'submit the detector-cleared PDF,' Acadly is the only tool of the two that reaches the end.

[See the pricing page](/pricing), [browse the feature list](/features), or [start on Free](/signup) and move one chapter of an in-progress draft into Paraphrase to see the per-run cap in practice.

How Acadly AI compares