Decision Support · Side-by-side
Compare pricing, strengths, and use cases so it is easier to pick the right fit.
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Sherlock AI Detector
Best overallFor most everyday users, Sherlock AI Detector wins because its generous free tier and sentence-level heatmap make it immediately useful for checking documents and web content without paying. AI Content Detector by SEOToolsKit is a solid alternative if you already use that SEO toolkit and need API access, but its unclear pricing and lack of mobile support hold it back. The single biggest difference: Sherlock gives you a free, detailed forensic report, while SEOToolsKit hides its full value behind a pricing wall.
Sherlock AI Detector
AI Content Detector
Scores at a glance
Choose Sherlock AI Detector if
Choose AI Content Detector if
Key differences
Facts side by side
| Sherlock AI Detector | AI Content Detector | |
|---|---|---|
| Free plan | ||
| Mobile app | ||
| API access |
Common questions
Yes, Sherlock is better because its free tier gives you a sentence-level heatmap that shows exactly which parts look AI-written, which is more useful for grading. SEOToolsKit only gives a percentage score and limits explanations in the free version.
No, neither has a mobile app. You can use both through a mobile web browser, but the experience is clunky. For phone use, you're better off with a dedicated app like GPTZero or Originality.ai.
Both are accurate for mainstream models like GPT-3.5 and GPT-4, but Sherlock's heatmap helps you spot false positives more easily. SEOToolsKit may struggle with heavily rewritten or niche content.
Sherlock's free tier includes a heatmap and basic report. SEOToolsKit's free version limits explanations, and you'll likely need to pay for a full PDF or CSV report. Sherlock is the better free option.
SEOToolsKit is better if you already use that SEO suite, because it integrates with your workflow. But for a standalone AI checker, Sherlock's free tier and detailed reports give you more value without extra cost.
Only SEOToolsKit has an API for automation. Sherlock does not offer an API, so you must manually upload each document. If you need to check hundreds of articles automatically, choose SEOToolsKit.
Sherlock AI Detector wins for everyday users with its free heatmap and document support; SEOToolsKit is only worth it if you need an API or already live in that SEO ecosystem.
If you just want a free, easy way to check if something was written by AI, start with Sherlock AI Detector — it gives you a detailed heatmap without asking for your credit card. Only pick SEOToolsKit's AI Content Detector if you're already using their SEO tools or need an API for automation. For most people, Sherlock is the smarter, safer choice.
Detail pages: Sherlock AI Detector · AI Content Detector
