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Compare pricing, strengths, and use cases so it is easier to pick the right fit.
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AI Detector by SEOToolZone
Best overallFor quick, free, no-strings-attached AI detection on short texts, SEOToolZone's AI Detector is the clear winner. Plagium offers a more powerful dual AI-and-plagiarism check with file uploads, but its free tier is severely limited. The biggest difference is price vs. capability: SEOToolZone is completely free but basic, while Plagium charges for serious use but gives you more tools.
AI Detector by SEOToolZone
AI Detector by Plagium
Scores at a glance
Choose AI Detector by SEOToolZone if
Choose AI Detector by Plagium if
Key differences
Facts side by side
| AI Detector by SEOToolZone | AI Detector by Plagium | |
|---|---|---|
| Free plan | ||
| Mobile app | ||
| API access |
Common questions
For a quick free check on a short essay, use SEOToolZone. For a longer paper with citations, Plagium's file upload and plagiarism check is more thorough, but you'll need a paid plan.
Neither has a mobile app, but both work in a mobile browser. SEOToolZone is simpler to use on a phone because you just paste text. Plagium's file uploads are harder on a small screen.
It gives a reasonable probability score for common AI writing patterns, but like all detectors, it can be fooled by edited AI text or very formal human writing. Don't treat it as definitive proof.
No, the free tier has a very low character limit (around 500-1000 characters). You'll need a paid plan to check full articles or documents.
SEOToolZone is better for daily quick checks because it's free and fast. Plagium only makes sense if you also want plagiarism checks and are willing to pay for a subscription.
SEOToolZone wins for free quick checks; Plagium wins for serious document analysis — pick based on whether your wallet or your workflow matters more.
If you just want a fast, free answer on whether a paragraph sounds like AI, start with SEOToolZone — it's zero hassle. If you regularly work with longer documents or need plagiarism checks too, Plagium is worth the small investment, but don't expect much from its free tier.
Detail pages: AI Detector by SEOToolZone · AI Detector by Plagium
