Anthropic Claude Haiku 4.5 vs OpenAI GPT-4o

Detailed comparison for LLMs

AnthropicOpenAI

On Guardion's LLM vulnerability Benchmark, Anthropic Claude Haiku 4.5 is the more secure of the two: Claude Haiku 4.5 scores 5.2% and GPT-4o scores 22.8% on attack success rate (ASR) (lower is better). One or both scores are estimated from public safety evaluations pending a Guardion benchmark run.

Head-to-Head Overview

Claude Haiku 4.5 is the overall winner in this comparison!

Attack Success Rate (lower is safer)

ASR for Anthropic Claude Haiku 4.5 vs OpenAI GPT-4o. Green marks the safer model on each metric. Only the overall score is available for estimated models.

Overall (ASR)

Claude Haiku 4.5
5.2%
GPT-4o
22.8%

TAP Attack Method (ASR)

Claude Haiku 4.5
100.0%
GPT-4o
39.6%

Crescendo Attack Method (ASR)

Claude Haiku 4.5
100.0%
GPT-4o
25.6%

Zero-Shot (ASR)

Claude Haiku 4.5
100.0%
GPT-4o
3.4%

Key Highlights

  • Anthropic Claude Haiku 4.5 has a lower Overall (ASR).
  • OpenAI GPT-4o has a lower TAP Attack Method (ASR).
  • OpenAI GPT-4o has a lower Crescendo Attack Method (ASR).
  • OpenAI GPT-4o has a lower Zero-Shot (ASR).

Security Profile

Outward is better on every axis.

OverallTAPCrescendoZero-Shot
Claude Haiku 4.5
GPT-4o
Full security profile
Anthropic Claude Haiku 4.5
Full security profile
OpenAI GPT-4o

Frequently asked questions

Is Anthropic Claude Haiku 4.5 or OpenAI GPT-4o more secure?

On Guardion's LLM vulnerability Benchmark, Anthropic Claude Haiku 4.5 is the more secure of the two: Claude Haiku 4.5 scores 5.2% and GPT-4o scores 22.8% on attack success rate (ASR) (lower is better). One or both scores are estimated from public safety evaluations pending a Guardion benchmark run.

What is the attack success rate (ASR) of Claude Haiku 4.5 vs GPT-4o?

Claude Haiku 4.5 has a 5.2% ASR and GPT-4o has a 22.8% ASR — the share of adversarial prompts that succeed across zero-shot, TAP, and Crescendo attacks. Lower is safer.

How were Claude Haiku 4.5 and GPT-4o tested?

Both were red-teamed with the HarmBench framework across zero-shot, TAP (Tree of Attacks with Pruning), and Crescendo multi-turn attacks, scored by Attack Success Rate.

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