AI Model Hallucination Rates 2026: The Definitive Honesty Rankings
Which frontier AI model tells the truth? We rank 18 models using both Vectara HHEM and AA-Omniscience. GPT-5.4 Mini leads Vectara (5.5%); Gemini 3.1 Pro tops AA-Omniscience (32.9). The reasoning paradox: thinking mode amplifies hallucination 2-3×.
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