Benchmark Almanac

BrowserART

Llama-3.1-405B-Instruct 10% tops its leaderboard Claude 3 Opus 11% leads the models we track
Not in model cards

Browser agents receive 100 harmful requests on synthetic and real websites. The test measures how often the agent attempts the harmful behavior that its backbone model would refuse in chat.

Some behaviors come from HarmBench and AIR-Bench 2024. Chat jailbreak methods transferred well to browser agents in the paper.

Made by
Scale AI and collaborators
Released
October 2024
Kind
Refusing harmful requests
Level
Expert
Scored
Graded by a model
Answers
Agent task
Tasks
All public
Strongest model tested
o1-mini #140 on the capability index
Last model added
September 2024
Scores refreshed
November 12th, 2026

In the authors’ words

For safety reasons, large language models (LLMs) are trained to refuse harmful user instructions, such as assisting dangerous activities. We study an open question in this work: does the desired safety refusal, typically enforced in chat contexts, generalize to non-chat and agentic use cases? Unlike chatbots, LLM agents equipped with general-purpose tools, such as web browsers and mobile devices, can directly influence the real world, making it even more crucial to refuse harmful instructions. In this work, we primarily focus on red-teaming browser agents, LLMs that manipulate information via web browsers. To this end, we introduce Browser Agent Red teaming Toolkit (BrowserART), a comprehensive test suite designed specifically for red-teaming browser agents. BrowserART is consist of 100 diverse browser-related harmful behaviors (including original behaviors and ones sourced from HarmBench [Mazeika et al., 2024] and AirBench 2024 [Zeng et al., 2024b]) across both synthetic and real websites. Our empirical study on state-of-the-art browser agents reveals that, while the backbone LLM refuses harmful instructions as a chatbot, the corresponding agent does not. Moreover, attack methods designed to jailbreak refusal-trained LLMs in the chat settings transfer effectively to browser agents. With human rewrites, GPT-4o and o1-preview-based browser agents attempted 98 and 63 harmful behaviors (out of 100), respectively. We publicly release BrowserART and call on LLM developers, policymakers, and agent developers to collaborate on improving agent safety

Abstract of Refusal-Trained LLMs Are Easily Jailbroken As Browser Agents (arXiv:2410.13886, CC0)
8
Entries on its own leaderboard, 6 models we track

Llama-3.1-405B-Instruct tops the leaderboard with 10%

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 best model we track is Claude 3 Opus, at 11%.

The newest model with a score here came out in September 2024, and nobody has tested a newer one. Among the 20 highest-ranked models on the capability index, these have no score yet:

  1. 1 Llama-3.1-405B-Instruct DA 10%
  2. 2 Claude 3 Opus DA 11%
  3. 3 o1-preview DA 13%
  4. 4 Claude 3.5 Sonnet DA 22%
  5. 5 o1-mini DA 24%
  6. 6 gemini-1.5-pro-001 DA 25%
  7. 7 GPT-4 Turbo Apr 2024, DA 67%
  8. 8 GPT-4o Aug 2024, DA 74%

Source: Official BrowserART leaderboard

#EntryScoreSettingDateSource
1 Llama-3.1-405B-Instruct 10% DA, BrowserART browser agent Official leaderboard
2 Claude 3 Opus 11% DA, BrowserART browser agent Feb 2024 Official leaderboard
3 o1-preview 13% DA, BrowserART browser agent Sep 2024 Official leaderboard
4 Claude 3.5 Sonnet 22% DA, BrowserART browser agent Jun 2024 Official leaderboard
5 o1-mini 24% DA, BrowserART browser agent Sep 2024 Official leaderboard
6 gemini-1.5-pro-001 25% DA, BrowserART browser agent Official leaderboard
7 GPT-4 Turbo Apr 2024 67% DA, BrowserART browser agent Apr 2024 Official leaderboard
8 GPT-4o Aug 2024 74% DA, BrowserART browser agent Aug 2024 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.

Lowest effort to highest, light to dark
GPT-4o BrowserART browser agent
DA + RS + GCG + Human
100%
GPT-4 Turbo BrowserART browser agent
DA + RS + GCG + Prefix
100%
o1-mini BrowserART browser agent
DA + GCG + Human
87%
Claude 3.5 Sonnet BrowserART browser agent
DA + GCG + Prefix + Human
75%
o1-preview BrowserART browser agent
DA + GCG + Human
66%
Claude 3 Opus BrowserART browser agent
DA + Human
41%

Source: Official BrowserART leaderboard

ModelEffortHarnessScoreCost per taskOutput tokens
GPT-4 Turbo Apr 2024 Ensemble BrowserART browser agent 100%
GPT-4o Aug 2024 Ensemble BrowserART browser agent 100%
GPT-4 Turbo Apr 2024 + Human BrowserART browser agent 99%
GPT-4o Aug 2024 + Human BrowserART browser agent 98%
GPT-4 Turbo Apr 2024 + Prefix BrowserART browser agent 95%
GPT-4o Aug 2024 + Prefix BrowserART browser agent 94%
GPT-4o Aug 2024 + GCG BrowserART browser agent 89%
o1-mini Ensemble BrowserART browser agent 87%
GPT-4 Turbo Apr 2024 + GCG BrowserART browser agent 85%
o1-mini + Human BrowserART browser agent 84%
GPT-4o Aug 2024 + RS BrowserART browser agent 82%
Claude 3.5 Sonnet Ensemble BrowserART browser agent 75%
GPT-4 Turbo Apr 2024 + RS BrowserART browser agent 74%
GPT-4o Aug 2024 DA BrowserART browser agent 74%
Claude 3.5 Sonnet + Human BrowserART browser agent 70%
GPT-4 Turbo Apr 2024 DA BrowserART browser agent 67%
o1-preview Ensemble BrowserART browser agent 66%
o1-preview + Human BrowserART browser agent 63%
Claude 3 Opus Ensemble BrowserART browser agent 41%
Claude 3 Opus + Human BrowserART browser agent 40%
Claude 3.5 Sonnet + Prefix BrowserART browser agent 37%
o1-mini + GCG BrowserART browser agent 35%
Claude 3.5 Sonnet + GCG BrowserART browser agent 30%
o1-mini + RS BrowserART browser agent 30%
o1-mini + Prefix BrowserART browser agent 25%
o1-mini DA BrowserART browser agent 24%
Claude 3.5 Sonnet DA BrowserART browser agent 22%
Claude 3.5 Sonnet + RS BrowserART browser agent 22%
o1-preview + RS BrowserART browser agent 21%
o1-preview + GCG BrowserART browser agent 20%
o1-preview + Prefix BrowserART browser agent 18%
Claude 3 Opus + GCG BrowserART browser agent 14%
o1-preview DA BrowserART browser agent 13%
Claude 3 Opus + RS BrowserART browser agent 12%
Claude 3 Opus DA BrowserART browser agent 11%
Claude 3 Opus + Prefix BrowserART browser agent 11%

Number one over time

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

Anthropic
Own leaderboard Not tested since Oct 2024

Source: Official BrowserART leaderboard

Scores over time

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

On the benchmark’s own leaderboard Best so far
0% 20% 40% 60% 80% 100% 2024 Claude 3 Opus Claude 3 Opus 0% 20% 40% 60% 80% 100% 2024 Claude 3 Opus Claude 3 Opus

Source: Official BrowserART 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.

More in Safety and alignment

All 465 in Safety and alignment
  • FORTRESS In use Paired adversarial and benign national-security misuse prompts. Rubric-graded risk score on adversarial and over-refusal score on benign prompts. Claude Opus 5.5 5.78%
  • StrongREJECT In use Forbidden-prompt jailbreak benchmark with a rubric grader that scores how useful a non-refusal actually is. Inkling 98.6%
  • Gray Swan IPI Arena benchmark In use Indirect prompt-injection attacks from public red-teaming competitions replayed on tool, coding and browser agents. Attack success rate at k attempts. Gemini 4 Carbon 0%
  • DistressBench In use Models reply as a chatbot to 718 simulated users in psychological crisis, in single-turn and multi-turn chats. Three judge models score replies against clinician-written rubrics. Muse Spark 1.2 88.4%
  • Lakera B3 (Backbone Breaker Benchmark) In use Crowdsourced prompt-injection attacks hit backbone LLMs inside agent threat snapshots at three defense levels. The score is attack resistance, 100 minus the board's vulnerability percentage. Claude Opus 4.5 89%
  • IHEval In use Models face conflicts between system, user and tool instructions. Reports a composite score for following the higher-priority instruction. GPT-4o 70%