Nejumi 4 - HalluLens: leaderboard

HalluLens hallucination test as run in Nejumi Leaderboard 4 (Weights & Biases Japan): prompts about nonexistent entities, with GPT-4.1 judging whether the model refuses or hallucinates. Score is Nejumi's hallucination_resistance rate (%); higher is better.

Metric: Hallucination resistance (%). Source: nejumi.ai. Saturation forecast: Not forecast. 145 models tracked.

Top models

#ModelScoreOverall rank
1Claude Sonnet 4.5 (Thinking)100#148 (Claude Sonnet 4.5)
2O3 (2025-04-16)100#125
3Claude Opus 5 (Max)100#16 (Claude Opus 5)
4Claude Opus 4.5 (Thinking)100#87 (Claude Opus 4.5)
5Claude Sonnet 4.6 (Thinking)100#94 (Claude Sonnet 4.6)
6Claude Opus 4.5 (Non-reasoning)100#87 (Claude Opus 4.5)
7Claude Opus 4.7 (xHigh)100#51 (Claude Opus 4.7)
8Claude Opus 4.8 (xHigh)100#39 (Claude Opus 4.8)
9Claude Sonnet 4 (Non-reasoning)100#207 (Claude Sonnet 4)
10Kimi K3 (Thinking)100#35 (Kimi K3)
11Claude Opus 4 (Non-reasoning)100#170 (Claude Opus 4)
12Kimi K3 (Max)99#35 (Kimi K3)
13Claude Opus 4.6 (Thinking)99#67 (Claude Opus 4.6)
14Claude Haiku 4.5 (Thinking)99#287 (Claude Haiku 4.5)
15Solar Pro 499#230

No result here: #3 Claude Opus 5.5, #6 GPT-6 Astra, #7 GPT-6.1 Sol.

Interactive version: theaggregate.ai/benchmark?slug=nejumi-4-hallulens · How It Works · Data refreshed daily, snapshot 2026-11-05.