Grammarly AI Detector

Grammarly AI Detector represents the 2026 standard in linguistic pattern analysis, designed to distinguish between human-generated text and outputs from major LLMs including GPT-5, Claude 4, and Gemini 2. Unlike basic perplexity checkers, Grammarly utilizes a proprietary 'Linguistic Fingerprinting' engine that analyzes syntactic variance, semantic consistency, and structural tropes typical of synthetic generation. As of 2026, the tool is deeply integrated into the broader Grammarly ecosystem, providing real-time 'Originality Scores' within the browser extension and desktop applications. The architecture leverages a transformer-based classifier trained on a multi-billion parameter dataset of both human and machine-generated corpora. For enterprise users, it offers bulk processing via the Grammarly for Developers SDK, allowing organizations to verify large-scale content pipelines. It operates with a focus on 'Explainable AI' (XAI), highlighting specific passages that exhibit high probability of machine generation rather than just providing a binary score, which is critical for legal and academic defensibility in a market saturated with generative content.