AI Detectors.io vs Originality.ai

AI Detectors.io analyzes text associated with major language models, returning an overall AI probability, confidence scores, and sentence-level results. The site also offers a humanizer, citation verification, plagiarism checking, grammar tools, and watermark removal. Its detector says it examines perplexity, burstiness, n-gram patterns, and stylometric fingerprints. The company reports 95.2% accuracy and 3.1% false positives from an April 2026 benchmark of 500 texts. The detector is trained and benchmarked on English; it returns scores for other languages, but those languages are outside that benchmark. Access is available through the web, Chrome extension, Microsoft Word add-in, and REST API. The Word add-in supports Word 2016 and later on Windows and Mac, as well as Word for the web, and can produce PDF reports. The free plan includes 10,000 words per month and a 500-word-per-use limit. Premium is listed at $8.33 a month, billed annually, with scans up to 25,000 words. Submitted text may be processed by third-party providers and retained as long as needed to support the service.

Originality.ai provides tools for checking AI-generated text, plagiarism, facts, readability, grammar, spelling and content quality. Its free Basic plan costs $0.00 per free and provides three AI scans per day, with up to 2,000 words per scan. The AI detector offers configurable allowances of 0%, 5%, 15%, 25% or 40%. A website scanner can crawl a site, identify pages likely to contain AI-generated content and run scheduled scans. The browser extension scans Google Docs, web pages or selected text, and includes writing replay, typing behavior insights and shareable reports. A REST-based API submits text for AI and plagiarism scans and returns detailed results; the maker says AI detection supports 30 languages. API AI scans require at least 50 words, and the help page says accuracy decreases below 100 words. Originality.ai describes detection results as probabilistic estimates that may produce false positives or false negatives, not conclusive proof. Pro costs $12.95 per month billed yearly, with a monthly option at $14.95 per month. The service is available through web, API and extension.