BaxBench
Models write backend servers from a specification. Each solution is checked for correctness by tests and for security by end to end exploits.
392 tasks from 28 scenarios across 14 backend frameworks. ICML 2025. The board toggles three prompt types: no security reminder, generic reminder and oracle reminder. MIT licensed dataset.
- Made by
- ETH Zurich SRI Lab, LogicStar.ai, UC Berkeley and INSAIT
- Released
- February 2025
- Kind
- Secure code and review
- Level
- Expert
- Scored
- Checked automatically
- Answers
- Code
- Tasks
- All public
- Strongest model tested
- Claude Opus 4.5 #61 on the capability index
- Last model added
- November 2025
- Scores refreshed
- November 12th, 2026
In the authors’ words
Automatic program generation has long been a fundamental challenge in computer science. Recent benchmarks have shown that large language models (LLMs) can effectively generate code at the function level, make code edits, and solve algorithmic coding tasks. However, to achieve full automation, LLMs should be able to generate production-quality, self-contained application modules. To evaluate the capabilities of LLMs in solving this challenge, we introduce BaxBench, a novel evaluation benchmark consisting of 392 tasks for the generation of backend applications. We focus on backends for three critical reasons: (i) they are practically relevant, building the core components of most modern web and cloud software, (ii) they are difficult to get right, requiring multiple functions and files to achieve the desired functionality, and (iii) they are security-critical, as they are exposed to untrusted third-parties, making secure solutions that prevent deployment-time attacks an imperative. BaxBench validates the functionality of the generated applications with comprehensive test cases, and assesses their security exposure by executing end-to-end exploits. Our experiments reveal key limitations of current LLMs in both functionality and security: (i) even the best model, OpenAI o1, achieves a mere 62% on code correctness; (ii) on average, we could successfully execute security exploits on around half of the correct programs generated by each LLM; and (iii) in less popular backend frameworks, models further struggle to generate correct and secure applications. Progress on BaxBench signifies important steps towards autonomous and secure software development with LLMs.
Claude Opus 4.5 leads with 68.6% among models released by November 2025
Best score per entry from the benchmark's own leaderboard, read on November 12th, 2026. Where a model ran with several settings or harnesses, we keep its best. Every run is in the next chart. Names in gray aren't in our model list: fine-tunes, agent systems, products and older models. They don't count toward leaders.
The newest model with a score here came out in November 2025, and nobody has tested a newer one. Among the 20 highest-ranked models on the capability index, these have no score yet:
- Claude Fable 5.2
-
Gemini 4 Carbon
- GPT-6 Astra
- Claude Opus 5.5
- and 16 more
- 68.6 Claude Opus 4.5
- 56.1 Claude Sonnet 4
- 54.3 GPT-5
- 48.2 o1
- 46.4 Claude 3.7 Sonnet
- 46.4 o3
- 45.9 o3-mini
- 43.6 Grok 4
- 40.8 GPT-4.1
- 39.0
DeepSeek-R1
- 37.2
Qwen3-Coder-480B-A35B
- 36.0 Claude 3.5 Sonnet
- 33.9 Grok 3
- 33.3
Gemini 2.5 Pro
- 32.6
Qwen3-235B-A22B
- 31.8 GPT-4.1 mini
- 30.5
DeepSeek-V3
- 30.4 GPT-4o New
- 27.7 Qwen Max
- 26.7 GPT-4o
- 25.5
QwQ-32B
- 24.7
DeepSeek-V3
- 23.3
Gemini 2.0 Flash
- 21.9
Llama 4 Maverick
- 18.4 Grok-2
- 15.8
Codestral
- 15.8 Qwen2.5 Coder
- 10.8
Mistral Small 3.1
- 10.7
Llama 3.3 70B
- 10.4
Qwen2.5-72B
- 6.63
DeepSeek-R1-Distill-Qwen-32B
- 5.94
DeepSeek-R1-Distill-Llama-70B
- 3.95
Gemma 2 27B
- 2.22
Qwen2.5-7B
- 1.89
Ministral 8B
- 1.79
DeepSeek-R1-Distill-Qwen-14B
- 0.0
DeepSeek-R1-Distill-Qwen-1.5B
- 1 Claude Opus 4.5 thinking, oracle security reminder 68.6%
- 2 Claude Sonnet 4 thinking, oracle security reminder 56.1%
- 3 GPT-5 54.3%
- 4 o1 oracle security reminder 48.2%
- 5 Claude 3.7 Sonnet thinking, oracle security reminder 46.4%
- 6 o3 46.4%
- 7 o3-mini oracle security reminder 45.9%
- 8 Grok 4 oracle security reminder 43.6%
- 9 GPT-4.1 40.8%
- 10
DeepSeek-R1 May 2025, oracle security reminder 39%
- 11
Qwen3-Coder-480B-A35B oracle security reminder 37.2%
- 12 Claude 3.5 Sonnet oracle security reminder 36%
- 13 Grok 3 thinking, oracle security reminder 33.9%
- 14
Gemini 2.5 Pro Jun 2025, oracle security reminder 33.3%
- 15
Qwen3-235B-A22B oracle security reminder 32.6%
- 16 GPT-4.1 mini oracle security reminder 31.8%
- 17
DeepSeek-V3 Mar 2025, oracle security reminder 30.5%
- 18 GPT-4o New oracle security reminder 30.4%
- 19 Qwen Max oracle security reminder 27.7%
- 20 GPT-4o Mar 2025, oracle security reminder 26.7%
- 21
QwQ-32B oracle security reminder 25.5%
- 22
DeepSeek-V3 oracle security reminder 24.7%
- 23
Gemini 2.0 Flash Feb 2025, oracle security reminder 23.3%
- 24
Llama 4 Maverick oracle security reminder 21.9%
- 25 Grok-2 Dec 2024, oracle security reminder 18.4%
- 26
Codestral oracle security reminder 15.8%
- 27 Qwen2.5 Coder oracle security reminder 15.8%
- 28
Mistral Small 3.1 oracle security reminder 10.8%
- 29
Llama 3.3 70B oracle security reminder 10.7%
- 30
Qwen2.5-72B oracle security reminder 10.4%
- 31
DeepSeek-R1-Distill-Qwen-32B oracle security reminder 6.63%
- 32
DeepSeek-R1-Distill-Llama-70B oracle security reminder 5.94%
- 33
Gemma 2 27B 3.95%
- 34
Qwen2.5-7B generic security reminder 2.22%
- 35
Ministral 8B generic security reminder 1.89%
- 36
DeepSeek-R1-Distill-Qwen-14B oracle security reminder 1.79%
- 37
DeepSeek-R1-Distill-Qwen-1.5B 0%
Source: Official BaxBench leaderboard
| # | Entry | Score | Setting | Date | Source |
|---|---|---|---|---|---|
| 1 | Claude Opus 4.5 | 68.6% | thinking, oracle security reminder | Nov 2025 | Official leaderboard |
| 2 | Claude Sonnet 4 | 56.1% | thinking, oracle security reminder | May 2025 | Official leaderboard |
| 3 | GPT-5 | 54.3% | Aug 2025 | Official leaderboard | |
| 4 | o1 | 48.2% | oracle security reminder | Dec 2024 | Official leaderboard |
| 5 | Claude 3.7 Sonnet | 46.4% | thinking, oracle security reminder | Feb 2025 | Official leaderboard |
| 6 | o3 | 46.4% | Apr 2025 | Official leaderboard | |
| 7 | o3-mini | 45.9% | oracle security reminder | Jan 2025 | Official leaderboard |
| 8 | Grok 4 | 43.6% | oracle security reminder | Jul 2025 | Official leaderboard |
| 9 | GPT-4.1 | 40.8% | Apr 2025 | Official leaderboard | |
| 10 | | 39% | oracle security reminder | May 2025 | Official leaderboard |
| 11 | | 37.2% | oracle security reminder | Jul 2025 | Official leaderboard |
| 12 | Claude 3.5 Sonnet | 36% | oracle security reminder | Jun 2024 | Official leaderboard |
| 13 | Grok 3 | 33.9% | thinking, oracle security reminder | Apr 2025 | Official leaderboard |
| 14 | | 33.3% | oracle security reminder | Jun 2025 | Official leaderboard |
| 15 | | 32.6% | oracle security reminder | Apr 2025 | Official leaderboard |
| 16 | GPT-4.1 mini | 31.8% | oracle security reminder | Apr 2025 | Official leaderboard |
| 17 | | 30.5% | oracle security reminder | Mar 2025 | Official leaderboard |
| 18 | GPT-4o New | 30.4% | oracle security reminder | Official leaderboard | |
| 19 | Qwen Max | 27.7% | oracle security reminder | Official leaderboard | |
| 20 | GPT-4o Mar 2025 | 26.7% | oracle security reminder | Mar 2025 | Official leaderboard |
| 21 | | 25.5% | oracle security reminder | Mar 2025 | Official leaderboard |
| 22 | | 24.7% | oracle security reminder | Dec 2024 | Official leaderboard |
| 23 | | 23.3% | oracle security reminder | Feb 2025 | Official leaderboard |
| 24 | | 21.9% | oracle security reminder | Apr 2025 | Official leaderboard |
| 25 | Grok-2 Dec 2024 | 18.4% | oracle security reminder | Dec 2024 | Official leaderboard |
| 26 | | 15.8% | oracle security reminder | Jan 2025 | Official leaderboard |
| 27 | Qwen2.5 Coder | 15.8% | oracle security reminder | Official leaderboard | |
| 28 | | 10.8% | oracle security reminder | Mar 2025 | Official leaderboard |
| 29 | | 10.7% | oracle security reminder | Dec 2024 | Official leaderboard |
| 30 | | 10.4% | oracle security reminder | Sep 2024 | Official leaderboard |
| 31 | | 6.63% | oracle security reminder | Jan 2025 | Official leaderboard |
| 32 | | 5.94% | oracle security reminder | Jan 2025 | Official leaderboard |
| 33 | | 3.95% | Jun 2024 | Official leaderboard | |
| 34 | | 2.22% | generic security reminder | Sep 2024 | Official leaderboard |
| 35 | | 1.89% | generic security reminder | Oct 2024 | Official leaderboard |
| 36 | | 1.79% | oracle security reminder | Jan 2025 | Official leaderboard |
| 37 | | 0% | Jan 2025 | Official leaderboard |
Scores at each effort level
Models the leaderboard ran at two or more effort levels. We don’t have enough cost data here to say what the extra effort costs.
Source: Official BaxBench leaderboard
| Model | Effort | Harness | Score | Cost per task | Output tokens |
|---|---|---|---|---|---|
| Claude Opus 4.5 | thinking, oracle security reminder | 68.6% | |||
| Claude Opus 4.5 | thinking, generic security reminder | 66.1% | |||
| Claude Sonnet 4 | thinking, oracle security reminder | 56.1% | |||
| Claude Opus 4.5 | thinking | 56.1% | |||
| GPT-5 | 54.3% | ||||
| Claude Sonnet 4 | thinking, generic security reminder | 49.5% | |||
| o1 | oracle security reminder | 48.2% | |||
| Claude 3.7 Sonnet | thinking, oracle security reminder | 46.4% | |||
| o3 | 46.4% | ||||
| GPT-5 | generic security reminder | 46.2% | |||
| o3-mini | oracle security reminder | 45.9% | |||
| Claude Sonnet 4 | thinking | 45.7% | |||
| Grok 4 | oracle security reminder | 43.6% | |||
| GPT-5 | oracle security reminder | 43.6% | |||
| Claude 3.7 Sonnet | thinking, generic security reminder | 43.4% | |||
| o3 | oracle security reminder | 41.8% | |||
| o3-mini | generic security reminder | 41.1% | |||
| GPT-4.1 | 40.8% | ||||
| Grok 4 | generic security reminder | 40.3% | |||
| o1 | generic security reminder | 40% | |||
| o3 | generic security reminder | 40% | |||
| | oracle security reminder | 39% | |||
| | oracle security reminder | 37.2% | |||
| GPT-4.1 | oracle security reminder | 37% | |||
| Claude 3.7 Sonnet | thinking | 37% | |||
| | generic security reminder | 37% | |||
| Claude 3.5 Sonnet | oracle security reminder | 36% | |||
| o3-mini | 34.4% | ||||
| | 34.4% | ||||
| Grok 3 | thinking, oracle security reminder | 33.9% | |||
| GPT-4.1 | generic security reminder | 33.8% | |||
| Grok 4 | 33.4% | ||||
| | oracle security reminder | 33.3% | |||
| Claude 3.5 Sonnet | generic security reminder | 33.2% | |||
| | oracle security reminder | 32.6% | |||
| Grok 3 | oracle security reminder | 32% | |||
| | 32% | ||||
| GPT-4.1 mini | oracle security reminder | 31.8% | |||
| | generic security reminder | 31.7% | |||
| Claude 3.5 Sonnet | 31.1% | ||||
| | generic security reminder | 30.9% | |||
| | oracle security reminder | 30.5% | |||
| Grok 3 | thinking, generic security reminder | 29.9% | |||
| | 29.7% | ||||
| GPT-4.1 mini | generic security reminder | 29.4% | |||
| | generic security reminder | 29.3% | |||
| o1 | 28.8% | ||||
| GPT-4.1 mini | 28.4% | ||||
| Grok 3 | generic security reminder | 28.3% | |||
| GPT-4o Mar 2025 | oracle security reminder | 26.7% | |||
| | oracle security reminder | 25.5% | |||
| Grok 3 | thinking | 25.5% | |||
| | generic security reminder | 25.1% | |||
| | oracle security reminder | 24.7% | |||
| | 23.4% | ||||
| | oracle security reminder | 23.3% | |||
| | 23.2% | ||||
| Grok 3 | 23.2% | ||||
| | generic security reminder | 23% | |||
| | generic security reminder | 21.9% | |||
| | oracle security reminder | 21.9% | |||
| GPT-4o Mar 2025 | generic security reminder | 20.4% | |||
| | 19.6% | ||||
| GPT-4o Mar 2025 | 19.3% | ||||
| | generic security reminder | 19% | |||
| | generic security reminder | 18.7% | |||
| Grok-2 Dec 2024 | oracle security reminder | 18.4% | |||
| | 17.4% | ||||
| | 17% | ||||
| | 16% | ||||
| | oracle security reminder | 15.8% | |||
| Grok-2 Dec 2024 | 13.2% | ||||
| Grok-2 Dec 2024 | generic security reminder | 13% | |||
| | 11.5% | ||||
| | oracle security reminder | 10.8% | |||
| | oracle security reminder | 10.7% | |||
| | generic security reminder | 10.7% | |||
| | oracle security reminder | 10.4% | |||
| | generic security reminder | 8.90% | |||
| | generic security reminder | 8.47% | |||
| | 8.24% | ||||
| | 7.88% | ||||
| | generic security reminder | 7.88% | |||
| | 7.58% | ||||
| | oracle security reminder | 6.63% | |||
| | generic security reminder | 6.20% | |||
| | oracle security reminder | 5.94% | |||
| | 5.43% | ||||
| | generic security reminder | 5.36% | |||
| | 4.95% | ||||
| | 3.95% | ||||
| | generic security reminder | 3.70% | |||
| | oracle security reminder | 3.57% | |||
| | generic security reminder | 2.22% | |||
| | generic security reminder | 1.89% | |||
| | 1.81% | ||||
| | oracle security reminder | 1.79% | |||
| | oracle security reminder | 1.76% | |||
| | oracle security reminder | 1.76% | |||
| | generic security reminder | 1.76% | |||
| | 1.73% | ||||
| | 1.51% | ||||
| | 0% | ||||
| | generic security reminder | 0% | |||
| | oracle security reminder | 0% |
3 models have held number one on the official leaderboard since its release in February 2025
Lab claims count from the day the card came out, independent runs from the model’s release.
Source: Official BaxBench leaderboard
Scores over time
All the scores we have, one dot each, so a model tested at several settings appears more than once.
Source: Official BaxBench leaderboard
No lab model card reports it yet
We read the headline results of 522 launch posts from 52 labs, and none of them list this benchmark.
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