Best GPTZero Alternatives (2026): 6 AI Detectors Compared

Pangram is the detector to try if GPTZero's misses worry you. It led the October 2025 University of Chicago study, with near-zero false positives and false negatives on medium and long passages, and it ranks #1 in both our best AI detectors and AI detectors for teachers rankings. The free plan checks 2,000 words a day in more than 20 languages, with a browser extension and Google Docs integration. The Individual plan costs $20 a month ($180 billed yearly) for 300,000 words and includes plagiarism detection. Its free allowance is daily rather than monthly, which suits steady checking more than one big batch.

Originality.ai is built for people who buy or publish content. One scan can check for AI writing and plagiarism together, and team features let editors share reports with writers. Pro costs $14.95 a month or $12.95 billed yearly for 2,000 credits, where one credit covers 100 words per check type. The free tier gives three AI scans a day of up to 2,000 words. It sat in the same second tier as GPTZero in the 2025 University of Chicago study, and was the stronger of the two at catching AI text. It ranks #3 in our best AI detectors.

QuillBot's detector is a good free second opinion. Without paying you can check up to 1,200 words per scan, six scans a day, and it explains why passages look AI-written. QuillBot Premium, at $8.33 a month billed yearly or $19.95 month to month, removes the scan limits and bundles the paraphraser, grammar checker and plagiarism checker. It ranks #4 in our best AI detectors. One caution: QuillBot also sells paraphrasing and humanizer tools, so it suits self-checks better than policing other people's work.

If your school already pays for Turnitin with the Originality add-on, its AI indicator sits next to the plagiarism report in your learning platform, so there is nothing new to buy or learn. Turnitin says its false positive rate is under 1% for documents with more than 20% AI writing, and it hides low scores behind an asterisk. Independent evidence is thin, several universities have switched it off, and students usually cannot see the AI report. Individuals cannot buy it. It ranks #5 in our best AI detectors; see GPTZero vs Turnitin.

Copyleaks covers more ground than GPTZero: AI text and image detection, text plagiarism, cross-language plagiarism and source code, with plug-ins for Canvas, Moodle and other platforms. The Personal plan costs $16.99 a month or $13.99 billed yearly for 100 credits, about 25,000 words, since one credit covers up to 250 words. Pro costs $99.99 a month ($74.99 billed yearly) for 1,000 credits, and education plans are quoted. It ranks #6 in our best AI detectors. Its accuracy record in independent tests is weaker than its long feature list suggests.

Grammarly's detector is free on the web and sits inside the writing tool many students already use, next to its plagiarism scan and Authorship reports that record how a document was written. Grammarly Pro, at $12 a month billed yearly or $30 month to month, adds the full plagiarism report with sources. Since June 2026 Grammarly and GPTZero share an owner, Superhuman. The catch is accuracy: it ranks #8 of nine in our best AI detectors, so use it for a quick look at your own writing rather than to judge anyone else's.