IA Checker vs QuillBot: Which AI Detector Should You Use in 2026?

Positioning

QuillBot's detector page markets sentence-level highlights, classification of AI-generated versus AI-refined writing, privacy-first messaging and image detection as a related surface. The brand's centre of gravity remains paraphrasing and writing assistance.

Scribbr's detector points readers to QuillBot for a more advanced option, which is useful context: these products sit in a related academic and writing ecosystem.

IA Checker is built around detection as the entry point to a European workspace. We concede QuillBot's paraphraser depth; we compete on how the score is framed and what happens to the text afterward.

Scorecard

Counted from the 21 rows in the table below, not asserted separately.

1. 9IA Checker ahead
2. 9Tied
3. 3QuillBot ahead

Feature comparison

Feature	IA Checker	QuillBot	Ahead
Accuracy
Detection engines	Multiple engines (Advanced and Ultra), with Pangram integration in progress	A QuillBot AI detector trained on major model families, per its detector page (quillbot.com)	IA Checker
AI-refined versus AI-generated classification	Scores and sentence signals; no four-way AI-refined taxonomy	Its site describes distinguishing fully AI-written, human-written and AI-refined text (quillbot.com)	QuillBot
Sentence-level highlights	Per-sentence signals with the passages that drove the score	Sentence-level highlights and section feedback are marketed on its detector page (quillbot.com)	Tied
How a result is framed	An indicator, with limits published alongside the score	Its pages discuss reliability and independent evaluation; treat marketing claims as product messaging (quillbot.com)	IA Checker
Models named as detectable	ChatGPT, Claude, Gemini and other current families	Its page names GPT-5, Gemini, Claude, Llama and more (quillbot.com)	Tied
Coverage
Text detection	Yes	Yes	Tied
Image detection	Dedicated image detection route	Its detector page promotes going beyond text to detect AI in images (quillbot.com)	Tied
Video detection	Dedicated video detection route	Not the focus of its published AI detector page (quillbot.com)	IA Checker
Paraphraser depth	Paraphraser is part of the paid workspace	Paraphrasing is the brand's core product, with a much deeper published suite (quillbot.com)	QuillBot
EU AI Act labelling	Built-in labelling tool with the official Article 50 disclosure icons	Not part of the published detector page (quillbot.com)	IA Checker
Pricing
Free detector access	Free checks up to 20,000 characters	A free AI detector is marketed on its detector page; Premium unlocks more of the writing suite (quillbot.com)	Tied
Entry paid plan	€4.90 per month for 100,000 words, 25,000 characters per check	Premium plans are sold for the wider QuillBot suite; verify the live pricing page for current figures (quillbot.com)	IA Checker
What you are mainly buying	Detection-led workspace with rewriting, plagiarism, translation and labelling	A paraphrasing and writing suite that also includes an AI detector (quillbot.com)	Tied
Privacy
Detector privacy messaging	Kept only for the duration of the requested operation unless you save it	Its detector page markets a privacy-first design; read the full QuillBot privacy policy for operative terms (quillbot.com)	IA Checker
Hosting region	European Union	Hosting region is not stated as EU-only on the detector page (quillbot.com)	IA Checker
Training on submissions	Not used for model training without express opt-in	Operative training terms are in QuillBot's privacy policy rather than the detector marketing page (quillbot.com)	Tied
Workflow
Writing suite integration	Detection plus humanizer, plagiarism, translation and grammar	Detector sits beside paraphraser, grammar, chat and browser extension workflows (quillbot.com)	QuillBot
Downloadable or shareable reports	Export and share flows for detection results on the product	Downloadable reports are listed among detector features on its page (quillbot.com)	Tied
Public API	No public API	No public AI detector API is advertised on the detector page (quillbot.com)	Tied
Compliance
EU AI Act labelling	Built-in labelling tool with the official Article 50 disclosure icons	Not part of the published detector suite	IA Checker
GDPR posture	EU-established, GDPR-first	Privacy-first messaging appears on the detector page; full GDPR detail lives in QuillBot policy pages (quillbot.com)	IA Checker

A paraphraser that detects, or a detector that writes

QuillBot's centre of gravity is rewriting. The AI detector is a strong adjacent tool for people who already paraphrase, humanize and grammar-check inside that suite. If that is your daily tab, switching brands just for detection is friction.

IA Checker flips the order. Detection comes first; rewriting and labelling follow when the score demands it. On iachecker.com the product is built so a result is harder to over-trust: more than one engine, limits beside the score.

Neither shape is universally better. It depends whether you open the tab to rewrite or to decide.

AI-refined writing is a useful lens

QuillBot's public detector messaging emphasises not only AI-versus-human scores but how AI may have been used: fully generated, refined, or mixed. That taxonomy matches how students and marketers actually write in 2026.

We show multi-engine disagreement instead. That answers a different question: not how the draft was produced, but whether independent detectors agree on the surface of the text.

If process classification is the main need, QuillBot's published framing is a real advantage. If challenge-resistant scoring is the main need, start at iachecker.com.

Privacy claims need the policy, not only the feature list

QuillBot's detector page markets privacy-first design. That is product messaging. The operative retention and training terms live in QuillBot's privacy policy; read that before pasting unpublished work.

We keep detector submissions only for the operation unless you save them, do not train without express opt-in, and process in the European Union. Those are commitments stated as product defaults.

For a quick student self-check the difference may not matter. For candidate material or EU procurement, defaults usually matter before paraphraser depth does.

IA Checker vs QuillBot FAQ

Is QuillBot's AI detector accurate?

QuillBot's detector pages discuss accuracy, independent evaluation and reliability. No detector can honestly claim universal accuracy. On iachecker.com we take a different approach: more than one engine, disagreement made visible, and the limits printed next to the score. That will not win every benchmark headline, but it makes a single percentage harder to over-trust. Test both on your own writing.

Can QuillBot tell AI-refined writing from fully AI-generated text?

Yes, according to its AI detector page. It describes distinguishing fully AI-written, human-written and AI-refined text, with section-level feedback. IA Checker focuses on multi-engine scores and sentence signals instead of that taxonomy.

How does QuillBot's detector relate to Scribbr's?

Scribbr's AI detector page points readers to QuillBot for a more advanced option. They sit in a related writing and academic ecosystem. If you are comparing student free checkers, read both pages; if you need an EU multi-engine workspace, compare them to iachecker.com as a third option.

Does QuillBot's AI detector also check plagiarism?

No. Its detector FAQ states the AI detector finds AI-written content and does not scan for plagiarism. QuillBot and related products offer separate plagiarism tools. IA Checker includes plagiarism review in the paid workspace beside detection.

IA Checker vs QuillBot: which should I choose?

Choose QuillBot if paraphrasing is your daily tool and you want a free detector with AI-refined classification in the same suite. Choose IA Checker on iachecker.com for multi-engine detection, EU hosting, short retention and EU AI Act labelling when the score has to carry more weight.

Read next

• How AI humanizers work
• EU AI labels: the 3 official icons
• Try the AI detector
• All comparisons