AI Detector Tools: An Honest Comparison
No AI detector is accurate enough to prove that a person used AI. Use one only as a rough signal, never as evidence on its own, and keep your drafts and version history as proof of your own process.
Updated 21 October 2026 · EssayWriting.com editorial team
- No AI detector is accurate enough to prove that a person used AI.
- We compare 3 tools on who they help, features and limitations.
- Price labels appear only where the tool’s homepage confirms them.
AI Detector Tools: An Honest Comparison: quick comparison
| Tool | Best for | Free or paid |
|---|---|---|
| GPTZero | Teachers and students who want a second opinion on whether text reads as AI-generated | Free and paid plans |
| ZeroGPT | Anyone wanting a quick no-sign-up AI-text check | Free and paid plans |
| Originality.ai | Publishers and content teams checking web content | Free and paid plans |
"Free or paid" is shown only when the tool’s own homepage states it; otherwise check the site. These are independent picks, not affiliate links.
1. GPTZero
AI-text detector. CAVEAT: all AI detectors produce false positives; not proof of misconduct
- Who it helps: Teachers and students who want a second opinion on whether text reads as AI-generated.
- Key features: Paste or upload text; sentence-level highlighting; overall probability score.
- Price: Free and paid plans (as stated on its homepage).
- Limitations: Can flag human writing as AI (false positives), especially formulaic or non-native writing; never proof on its own.
2. ZeroGPT
AI-text detector. CAVEAT: unreliable, false positives especially on non-native English
- Who it helps: Anyone wanting a quick no-sign-up AI-text check.
- Key features: Paste text and get a percentage score.
- Price: Free and paid plans (as stated on its homepage).
- Limitations: Accuracy is disputed and false positives are reported; treat results as a rough signal only.
3. Originality.ai
Paid AI and plagiarism detector aimed at publishers. CAVEAT: probabilistic, not proof
- Who it helps: Publishers and content teams checking web content.
- Key features: AI-text detection combined with plagiarism checking; team features.
- Price: Free and paid plans (as stated on its homepage).
- Limitations: Aimed at professional content rather than student essays; like all detectors it produces false positives.
Related guides
Frequently asked questions
Which AI detector is most accurate?
None is reliable enough to prove AI use. Accuracy claims vary by vendor and by test, and independent research has found false positives, including higher rates for non-native English writers.
Can I rely on an AI detector score?
No. Treat it as one signal. Version history, drafts and a conversation about the work are much stronger evidence.
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