Free AI Detector vs DetectGPT
Free AI Detector and DetectGPT are both detection-side tools, and the honest headline is that detectors are noisy: scores vary by text type, and false positives on human writing are a documented problem. Free AI Detector positions itself as the no-cost, quick-check option: paste in text up to 10,000 characters and get an AI-likelihood verdict with sentence-level highlights; results are approximate guidance, not proof of authorship. DetectGPT (detectgpt.com) is a detection product for teachers, students and writers: free scanning up to 5,000 characters with no credit card required, and paid plans listed on the homepage at $15/month (Essential, 50,000 words, 1 seat), $29/month (Pro, 250,000 words, 3 members) and $59/month (Team, 500,000 words, unlimited members), with a yearly option showing 6 months free (homepage read 2026-11-04; the page names no currency for these amounts). We could not verify exact feature depth for either product, so check both official sites. The practical advice: never treat any single detector score as a verdict. Run the same text through two or three detectors, and treat disagreement between them as information, not error. We did not hands-on test either product, so no quality winner is declared.
| Decision point | Free AI Detector | DetectGPT |
|---|---|---|
| Best suited to | Writers and editors who want a quick, approximate check of whether a text reads as AI-written, with sentence-level highlights. | Teachers, students and writers that need to check whether content is flagged as AI across models including ChatGPT, GPT-4 and Gemini.; Clients and editors that want shareable original-content certification for human-written work. |
| Plans and cost | Listed as a Free plan Mod in the Moxby marketplace; no paid tier amounts were read in this pass. | The homepage pricing section lists Essential at $15 per month for 50,000 words per month and 1 user seat, Pro at $29 per month for 250,000 words per month and 3 team members, and Team at $59 per month for 500,000 words per month and unlimited team members, with a yearly option showing 6 months free; the page read names no currency for these $ amounts, so no charge fact is recorded. Free scanning starts at up to 5,000 characters with no credit card required. |
| Limitations | Results are explicitly approximate guidance, not proof of authorship. The page now carries Moxby branding rather than the original Content at Scale branding. | Free scanning is capped at 5,000 characters in the text read, so long documents need a paid plan.; Detection is a probability judgement, not proof of authorship, so results need human review before acting on them. |
Use the same input
A teacher or editor needs a free way to sanity-check suspicious text and wants to know which detector to trust.
What a successful result must preserve
The tool must match the real job (quick screening) and the verdict must come from multiple sources, since no detector is reliable alone.
Evidence and test status
Specification comparison based on the two vendors' published feature and pricing pages. DetectGPT's plans come from the detectgpt.com homepage read 2026-11-04. Free AI Detector's limits come from its product page. No research paper is used as backing for either product. We did not run a hands-on test on either tool; no quality winner is declared.
- Free AI Detector — Official homepage ↗ (reviewed 2026-11-07)
- DetectGPT — AI Detector - AI Checker For Teachers, Students & Writers ↗