GPTZero

Adoption verdict: GPTZero works as a first-pass screening tool, useful for teachers or editors who need a sanity check. It should not be used as the sole basis for academic discipline or in high-stakes domains where false positives could cause real harm.

What it does: It scores text based on perplexity and burstiness, estimating the likelihood of AI involvement. Features include batch uploads, API access, and integrated plagiarism scanning. In practice, fandoms have used it alongside other detectors to verify AI-generated fanfiction, and academic conferences have trialled it to flag synthetic citations. However, these implementations remain case-specific rather than standardised industry practice.

Cost and barriers: The free tier allows detection for texts up to 5,000 characters; paid plans unlock higher limits and premium capabilities. No official, publicly verifiable pricing page has been documented in the provided evidence—community posts show users reselling checks, which signals demand but does not constitute a reliable price commitment.