Google Gemini 3 Flash vs OpenAI o3-mini
Detailed comparison for LLMs
On Guardion's LLM vulnerability Benchmark, OpenAI o3-mini is the more secure of the two: Gemini 3 Flash scores 10.0% and o3-mini scores 9.0% 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
o3-mini is the overall winner in this comparison!
Attack Success Rate (lower is safer)
ASR for Google Gemini 3 Flash vs OpenAI o3-mini. Green marks the safer model on each metric. Only the overall score is available for estimated models.
Overall (ASR)
TAP Attack Method (ASR)
Crescendo Attack Method (ASR)
Zero-Shot (ASR)
Key Highlights
- OpenAI o3-mini has a lower Overall (ASR).
Security Profile
Outward is better on every axis.
Frequently asked questions
Is Google Gemini 3 Flash or OpenAI o3-mini more secure?
On Guardion's LLM vulnerability Benchmark, OpenAI o3-mini is the more secure of the two: Gemini 3 Flash scores 10.0% and o3-mini scores 9.0% 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 Gemini 3 Flash vs o3-mini?
Gemini 3 Flash has a 10.0% ASR and o3-mini has a 9.0% ASR — the share of adversarial prompts that succeed across zero-shot, TAP, and Crescendo attacks. Lower is safer.
How were Gemini 3 Flash and o3-mini 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.