# Claude Mythos Preview Benchmark Scores & Performance

> Claude Mythos Preview by Anthropic has 5 source-displayable benchmark rows but no public overall score. It remains unranked.

Canonical page: https://benchlm.ai/models/claude-mythos-preview

Last updated: October 5, 2026

## Model Details

| Property | Value |
|----------|-------|
| Creator | Anthropic |
| Source Type | Proprietary |
| Reasoning Type | Reasoning |
| Context Window | Coming soon |
| Official model card | [Claude Mythos Preview system card](https://www-cdn.anthropic.com/7624816413e9b4d2e3ba620c5a5e091b98b190a5/Claude%20Mythos%20Preview%20System%20Card.pdf) |
| Overall Score | Not computed (unranked) |
| Overall Rank | Unranked |

## Family & Coverage

- Family: Claude Mythos
- Variant: preview (preview)
- Benchmarks covered: 5 of 649
- Sibling models: [Claude Mythos 5](/models/claude-mythos-5), [Claude Mythos 5.1](/models/claude-mythos-5-1)
- Coverage note: Published evidence is shown below; no public overall score is assigned.

## Agentic Benchmarks

| Benchmark | Score | Source |
|-----------|-------|--------|
| [CyberGym](/benchmarks/cybergym) | 83.1% | [CyberGym leaderboard](https://cybergym.io/) |
| [ExploitGym](/benchmarks/exploitgym) | 17.5% | [ExploitGym paper](https://arxiv.org/abs/2605.11086) |

## Other Anthropic Models

- [Claude Opus 5.5](/models/claude-opus-5-5) - Score: 86.37
- [Claude Sonnet 5.5](/models/claude-sonnet-5-5) - Score: 83.87
- [Claude Fable 5.1](/models/claude-fable-5-1) - Score: 81.74
- [Claude Opus 5](/models/claude-opus-5) - Score: 79.36
- [Claude Fable 5](/models/claude-fable) - Score: 78.82
- [Claude Opus 4.8](/models/claude-opus-4-8) - Score: 69.07
- [Claude Opus 4.7 (Adaptive)](/models/claude-opus-4-7-adaptive) - Score: 67.92
- [Claude Sonnet 5](/models/claude-sonnet-5) - Score: 65.96
- [Claude Opus 4.7](/models/claude-opus-4-7) - Score: 64.13
- [Claude Opus 4.6](/models/claude-opus-4-6) - Score: 62.04
- [Claude Sonnet 4.6](/models/claude-sonnet-4-6) - Score: 55.25
- [Claude Opus 4.5 Thinking](/models/claude-opus-4-5-thinking) - Score: 54.11
- [Claude Opus 4.5](/models/claude-opus-4-5) - Score: 54.06
- [Claude Sonnet 4.5](/models/claude-sonnet-4-5) - Score: 48.54
- [Claude Haiku 4.5](/models/claude-haiku-4-5) - Score: 41.5
- [Claude 4.1 Opus](/models/claude-4-1-opus) - Score: 40.37
- [Claude 4.1 Opus Thinking](/models/claude-4-1-opus-thinking) - Score: 39.93
- [Claude 4 Sonnet](/models/claude-4-sonnet) - Score: 38.42
- [Claude 3 Opus](/models/claude-3-opus) - Score: 28.75
- [Claude 3.5 Sonnet](/models/claude-3-5-sonnet) - Score: 28.38
- [Claude 3 Haiku](/models/claude-3-haiku) - Score: 14.58
- [Claude Mythos 5](/models/claude-mythos-5) - Score: not computed
- [Claude Opus 4.6 (Adaptive)](/models/claude-opus-4-6-thinking) - Score: not computed
- [Claude Sonnet 4.5 Thinking](/models/claude-sonnet-4-5-thinking) - Score: not computed
- [Claude Mythos 5.1](/models/claude-mythos-5-1) - Score: not computed
- [Claude Haiku 4.5 Thinking](/models/claude-haiku-4-5-thinking) - Score: not computed