Benchmark Almanac

Honesty human feedback win rate (Anthropic)

Claude 3 Sonnet 69% leads since Sep 2025 Only in system cards

Crowdworkers try to make models say something false and pick the more honest reply in head-to-head chats. Score is the win rate against a baseline.

In-house Anthropic evaluation. The baseline model was Claude Sonnet 4, so 50% means equal honesty.

Made by Anthropic Released Sep 2025 Hallucination rates Tasks kept private Last in a system card Feb 2026 Last model added Feb 2026
Level
Everyday Most adults, without training
Scored
Ranked by votes People pick the better of two answers, as in an arena, and the votes are turned into ratings.
Answers
Open-ended Free-form text, documents, designs or media judged as a whole.
6
Models scored in lab cards
6
System cards report it, from 1 lab

Claude 3 Sonnet leads with 69% among models released by Feb 2026

Best score per model as labs report them in their own cards. Labs pick their own settings, so these compare less cleanly than independent runs.

The newest model with a score here came out in Feb 2026, and nobody has reported a newer one. Among the 20 highest-ranked models on the capability index, these have no score yet:

  1. 1 Claude 3 Sonnet 69%
  2. 2 Claude 3.5 Sonnet 66%
  3. 3 Claude Opus 4.6 61%
  4. 4 Claude Sonnet 4.5 57%
  5. 5 Claude 3.5 Sonnet (October 2024) 55%
  6. 6 Claude 3.5 Haiku 42%
#ModelScoreSettingDateSource
1 Claude 3 Sonnet 69% Mar 2024 Model card
2 Claude 3.5 Sonnet 66% Jun 2024 Model card
3 Claude Opus 4.6 61% Feb 2026 Model card
4 Claude Sonnet 4.5 57% Sep 2025 Model card
5 Claude 3.5 Sonnet (October 2024) 55% Oct 2024 Model card
6 Claude 3.5 Haiku 42% Oct 2024 Model card

Number one over time

Lab claims count from the day the card came out, independent runs from the model’s release.

Anthropic
Lab claims Not tested since Feb 2026

Scores over time

All the scores we have, one dot each, so a model tested at several settings appears more than once.

Reported by the lab in its model card
0% 20% 40% 60% 80% 100% 2024 2025 2026 Near the ceiling (85%) Claude 3 Sonnet 0% 20% 40% 60% 80% 100% 2024 2025 2026 Near the ceiling (85%) Claude 3 Sonnet

Labs report it only in system cards

We read the headline results of 479 launch posts from 51 labs, and none of them list this benchmark. Some system cards do, below.

6 system cards report it, from 1 lab

Besides launch posts, we read the system cards, model cards and technical reports labs publish with a release. They report far more, including safety and frontier-risk tests.

DateDocumentScoreAs the document writes itSection
5 Feb 2026 Claude Opus 4.6 system card 61 Honesty HF win rate against a Claude Opus 4.5 baseline, 64k thinking, value printed on chart; 54 without thinking (Figure 4.1.A) Hallucination
29 Sep 2025 Claude Sonnet 4.5 system card 57 Honesty HF win rate against Claude Sonnet 4, Claude Sonnet 4.5 with 16k thinking 57. Without thinking 50 (Figure 3.1.A) Hallucination
22 Oct 2024 Claude 3.5 Sonnet (October 2024) model card 55 Human feedback win rate vs Claude 3.5 Sonnet baseline, Honesty (adversarial scenario) 55 (Figure 2) Safety
22 Oct 2024 Claude 3.5 Haiku model card 42 Human feedback win rate vs Claude 3.5 Sonnet baseline, Honesty (adversarial scenario) 42 (Figure 2) Safety
20 Jun 2024 Claude 3.5 Sonnet model card 66 Honesty, human preference win rate vs Claude 3 Opus baseline, adversarial scenarios (Figure 3) Safety
4 Mar 2024 Claude 3 Sonnet model card 69 Human preference win rate vs Helpful-only baseline, Honesty (adversarial scenario) 69 (Figure 8) Safety

More in Factuality

All 70 in Factuality
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  • HallusionBench In use Models answer 1,129 yes or no questions about 346 images, built in pairs to expose language hallucination and visual illusion. Scored by accuracy. Keye-VL-2.0-30B-A3B 73.5%
  • SimpleQA Verified In use 1,000 human-verified, de-duplicated short-answer factual questions measuring parametric knowledge. Gemini 3.1 Pro 77.5%
  • GaRAGe In use Models write long-form RAG answers to 2,366 questions with human-annotated grounding passages. Scoring checks whether answers use the relevant passages. Nemotron 3.5 Bolt E4B 40.7%
  • Kimi Hallu Bench In use Models answer hard prompts drawn from practical work tasks. Fact-checking agents score the share of claims that are hallucinated. Kimi K3.1 Pro 8.30%
  • RAGTruth In use A word-level annotated corpus of hallucinations in retrieval-augmented generation answers. It is used to train and evaluate hallucination detection and RAG faithfulness. Nemotron 3.5 Bolt E4B 77.9%