Safety · Anthropic

Claude Sonnet 4.5 on TruthfulQA: score, rank and what it means

Claude Sonnet 4.5 scores 87.2 on TruthfulQA, placing it #33 of 600 models in the index. The benchmark average is 73.6 and the leader is GPT-5.1 Max at 91.1.

Score
87.2
0–100 scale
Rank
#33
of 600
Percentile
95th
within the index
Benchmark avg
73.6
all models
Leader
91.1
GPT-5.1 Max
Gap to leader
3.9
points

Score distribution

The chart shows the top 10 models on TruthfulQA, with Claude Sonnet 4.5 highlighted. Longer bars mean higher scores.

GPT-5.1 Max 91.1
Gemini 3 Pro Reasoning 90.3
GPT-5.1 Reasoning 90.0
GPT-5.2 Pro 90.0
GPT-5.2 89.7
Gemini 3 Pro Max 89.6
Grok 4 Reasoning 89.4
Qwen3-Max Max 89.3
GPT-5.1 89.2
GPT-5.1 Turbo 89.2

Top 10 leaderboard

#ModelProviderContextInput / 1MAvg score
1 GPT-5.1 Max OpenAI 2000000 $20.50 87.9
2 Gemini 3 Pro Reasoning Google DeepMind 200000 $19.69 87.5
3 GPT-5.1 Reasoning OpenAI 400000 $20.27 88.3
4 GPT-5.2 Pro OpenAI 2000000 $21.32 89.6
5 GPT-5.2 OpenAI 2000000 $19.71 88.0
6 Gemini 3 Pro Max Google DeepMind 2000000 $20.57 87.9
7 Grok 4 Reasoning xAI 2000000 $19.67 87.8
8 Qwen3-Max Max Alibaba Cloud 400000 $18.53 85.9
9 GPT-5.1 OpenAI 2000000 $19.01 86.0
10 GPT-5.1 Turbo OpenAI 2000000 $19.19 86.1

What this score means

On TruthfulQA, Claude Sonnet 4.5 sits at #33 of 600. The leader, GPT-5.1 Max, scores 91.1, so the gap to the top is 3.9 points. The median model in this index scores 76.3, which puts Claude Sonnet 4.5 above the midpoint.

Anthropic models average 82.9 on this benchmark. Claude Sonnet 4.5 is 4.3 points above that provider line, so it is a stronger result than the average Anthropic model.

Among frontier models, the average is 86.9. Claude Sonnet 4.5 is 0.3 points above that group. This is the more useful comparison if you are shortlisting within the same tier rather than across the whole index.

Read a 87.2 as a relative signal, not an absolute guarantee. Benchmark scores depend on prompt format, evaluation harness and contamination controls. Use this page to narrow the shortlist, then test the model on your own data.

Price context

At $17.84 per million input tokens, Claude Sonnet 4.5 is above the median input price of $4.00 across the 600 models scored on TruthfulQA. The models immediately around it in the ranking are shown below so you can compare score and price together.

ModelProviderContextInput / 1MAvg score
Gemini 3 Flash Turbo Google DeepMind 200000 $17.07 84.1
Claude Sonnet 4.5 Max Anthropic 1000000 $19.90 87.2
GPT-5.2 Turbo OpenAI 1000000 $20.73 87.4
o3 Max OpenAI 2000000 $17.82 84.8
Claude Sonnet 4.5 Anthropic 400000 $17.84 86.0
Gemini 3 Flash Max Google DeepMind 1000000 $17.43 85.0
o4 Max OpenAI 2000000 $19.51 86.2

Other benchmarks for Claude Sonnet 4.5

BenchmarkScoreRankPercentileRelative
MMLU-Pro 88.0 17 97th
GPQA Diamond 82.6 23 96th
SWE-bench Verified 74.2 50 92th
HumanEval 92.7 12 98th
MATH-500 87.0 76 87th
AIME 2025 86.3 25 96th
LiveCodeBench 82.5 19 97th
IFEval 91.1 50 92th
HellaSwag 93.0 23 96th
MMMU 80.9 44 93th
Arena Elo 1478.2 21 97th

FAQ

What score does Claude Sonnet 4.5 get on TruthfulQA?

Claude Sonnet 4.5 scores 87.2 on TruthfulQA in this index. The benchmark average is 73.6 and the top score is 91.1.

How does Claude Sonnet 4.5 rank on TruthfulQA?

It ranks #33 of 600 models, in the 95th percentile. The leader is GPT-5.1 Max at 91.1.

Is Claude Sonnet 4.5 good at TruthfulQA?

Yes, relative to the index: it is above the median and inside the top half of scores. The result should be read alongside its price and context window.

How is the TruthfulQA score calculated?

TruthfulQA is a safety benchmark. Scores in this index are modelled estimates on a 0–100 scale (or Elo for Arena), derived from capability tier and benchmark difficulty. They are not official leaderboard results.

What does Claude Sonnet 4.5 cost?

Claude Sonnet 4.5 costs $17.84 per million input tokens and $70.50 per million output tokens.

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