Claude Opus 5
26 values about Claude Opus 5 from 3 documents, in 5 metric families. In each family, values from its own document come first.
- Developer
- Anthropic
- Release date
- 24 Jul 2026The date of its first card in the dataset, the Claude Opus 5 System Card.
- Availability
- Public
- Its own document
- Claude Opus 5 System Card · 24 Jul 2026
- Also reported in
- Claude Fable 5.1 & Claude Mythos 5.1 System Card · 1 Sep 2026
- Claude Opus 5.5 System Card · 22 Sep 2026
Data as of 26 Sep 2026 · Dataset v0.1 · Methodology v0.1 · Changelog
Values by metric family
Each value as the document printed it. Select a value for its source, its checks and its history. Values from other documents are listed after the model’s own, each marked as the first report of that measure or as a restatement.
KeyVerifiedUnverifiedDisputedCorrected read off a figure or stated in wordsA value opens its source and history.
M3 · Sabotage and sandbagging 2 values
| Evaluation and metric | Value | Document |
|---|---|---|
| From its own documentClaude Opus 5 System Card · 24 Jul 2026 | ||
| Safety research compromiseRate of compromising safety research | Claude Opus 5 System Card24 Jul 2026 | |
| SHADE-Arena / LinuxArenaStealth success vs peers | Claude Opus 5 System Card24 Jul 2026 | |
M4 · Misalignment audits 1 value
| Evaluation and metric | Value | Document |
|---|---|---|
| From its own documentClaude Opus 5 System Card · 24 Jul 2026 | ||
| Internal deployment monitoringCircumvention attempts in monitored completions | Claude Opus 5 System Card24 Jul 2026 | |
M7 · Harmful compliance and over-refusal 6 values
| Evaluation and metric | Value | Document |
|---|---|---|
| From its own documentClaude Opus 5 System Card · 24 Jul 2026 | ||
| Child safety single-turn violative requestsHarmless response rateCondition: API | Claude Opus 5 System Card24 Jul 2026 | |
| Single-turn benign requestsOver-refusal rateCondition: claude.ai system prompt | Claude Opus 5 System Card24 Jul 2026 | |
| Single-turn benign requestsOver-refusal rateCondition: no system prompt; API | Claude Opus 5 System Card24 Jul 2026 | |
| Single-turn violative requestsHarmless response rateCondition: claude.ai system prompt | Claude Opus 5 System Card24 Jul 2026 | |
| Single-turn violative requestsHarmless response rateCondition: no system prompt; API | Claude Opus 5 System Card24 Jul 2026 | |
| Suicide/self-harm multi-turnAppropriate response rateCondition: claude.ai | Claude Opus 5 System Card24 Jul 2026 | |
M9 · Prompt injection 1 value
| Evaluation and metric | Value | Document |
|---|---|---|
| From its own documentClaude Opus 5 System Card · 24 Jul 2026 | ||
| Indirect prompt injection (ART-style)Attacker success within 15 attempts | Claude Opus 5 System Card24 Jul 2026 | |
M10 · Dangerous capabilities and risk determinations 16 values
| Evaluation and metric | Value | Document |
|---|---|---|
| From its own documentClaude Opus 5 System Card · 24 Jul 2026 | ||
| AI R&D kernel taskBest speedup | Claude Opus 5 System Card24 Jul 2026 | |
| AI R&D LLM training taskAverage speedupCondition: easy variant | Claude Opus 5 System Card24 Jul 2026 | |
| AI R&D novel compiler taskPass rate | Claude Opus 5 System Card24 Jul 2026 | |
| AI R&D quadruped RL taskHighest scoreCondition: no hparams | Claude Opus 5 System Card24 Jul 2026 | |
| Anthropic ECI (AECI)Capability indexRestated later: compare with the later value | Claude Opus 5 System Card24 Jul 2026Restated later: compare with the later value | |
| CyScenarioBenchSolve rate | Claude Opus 5 System Card24 Jul 2026 | |
| DNA synthesis screening evasionPathogens with viable evasionCondition: of 10 pathogens | Claude Opus 5 System Card24 Jul 2026 | |
| ExploitBenchMean flags capturedCondition: AutoNudge arm | Claude Opus 5 System Card24 Jul 2026 | |
| Firefox 147 exploitationFull exploit rate | Claude Opus 5 System Card24 Jul 2026 | |
| Long-form virology task 1Score | Claude Opus 5 System Card24 Jul 2026 | |
| Long-form virology task 2Score | Claude Opus 5 System Card24 Jul 2026 | |
| Multimodal virology (VCT)Score | Claude Opus 5 System Card24 Jul 2026 | |
| RSP determinationsCB-2 / AI R&D threshold | Claude Opus 5 System Card24 Jul 2026 | |
| From other documents | ||
| Anthropic ECI (AECI)Capability indexClaude Fable 5.1 & Claude Mythos 5.1 System Card1 Sep 2026Restated: compare with the earlier value | Claude Fable 5.1 & Claude Mythos 5.1 System Card1 Sep 2026Restated: compare with the earlier value | |
| Anthropic ECI (AECI)Capability indexClaude Opus 5.5 System Card22 Sep 2026First reported | Claude Opus 5.5 System Card22 Sep 2026First reported | |
| CoBenchScoreClaude Opus 5.5 System Card22 Sep 2026First reported | Claude Opus 5.5 System Card22 Sep 2026First reported | |
Restated in later documents
A later document reported a value about Claude Opus 5 again. Each pair is shown side by side: both values are kept with their own documents, and the later one does not replace the earlier.
| Earlier value | Later value |
|---|---|
| M10 · Dangerous capabilities and risk determinations | |
| Anthropic ECI (AECI)Capability index | |
| Claude Opus 5 System Card24 Jul 2026 · its own document | Claude Fable 5.1 & Claude Mythos 5.1 System Card1 Sep 2026No reason stated |
Risk determinations
The developer's formal decisions about Claude Opus 5 under its framework, as printed. Levels from different frameworks do not map onto one another.
| Domain | Level as printed | Framework and document |
|---|---|---|
| Overall | ASL-3 protections Responsible Scaling Policy Claude Opus 5 System Card · 24 Jul 2026 | Responsible Scaling Policy Claude Opus 5 System Card · 24 Jul 2026 |
| Bio/chem | neither crossed Responsible Scaling Policy Claude Opus 5 System Card · 24 Jul 2026 | Responsible Scaling Policy Claude Opus 5 System Card · 24 Jul 2026 |
| AI R&D / autonomy | neither crossed Responsible Scaling Policy Claude Opus 5 System Card · 24 Jul 2026 | Responsible Scaling Policy Claude Opus 5 System Card · 24 Jul 2026 |