# Claude Mythos Preview vs Claude Opus 5

> Claude Opus 5 has enough public results to be ranked (#4); Claude Mythos Preview does not yet, so treat this comparison as directional.

- Canonical page: https://noometry.com/compare/claude-mythos-preview-vs-claude-opus-5
- Last updated: 2026-10-10
- Shared benchmarks: 0

## Summary

- The widest gap is in agentic & tool use, where Claude Opus 5 leads 55.6 to 41.4.

## Snapshot

| | Claude Mythos Preview | Claude Opus 5 |
|---|---|---|
| Provider | Anthropic | Anthropic |
| Noometry Index | 41.2 | 67.8 |
| Rank | — | 4 |
| Context | — | 1M |
| Input $/M | — | $5 |
| Output $/M | — | $25 |
| Weights | Proprietary | Proprietary |

## Coding

- Claude Mythos Preview: —
- Claude Opus 5: 67.5 (#5)

| Benchmark | Claude Mythos Preview | Claude Opus 5 |
|---|---|---|
| DeepSWE | — | 73.6% |
| FrontierCode | — | 53.4% |
| CursorBench | — | 46.6% |
| LMArena WebDev | — | 1691 |
| FrontierSWE | — | 52% |
| SciCode | — | 56.4% |
| WeirdML | — | 91.8% |
| LMArena Coding | — | 1534 |
| ALE-Bench | — | 2,165 |

## Agentic & Tool Use

- Claude Mythos Preview: 41.4
- Claude Opus 5: 55.6 (#1)

| Benchmark | Claude Mythos Preview | Claude Opus 5 |
|---|---|---|
| APEX-Agents | — | 65.8% |
| OSWorld 2.0 | — | 31.4% |
| τ²-bench Banking | — | 48.7% |
| PostTrainBench | — | 35% |
| BALROG | — | 63.4% |
| ExploitBench | 73.8% | — |
| GBAEval | — | 79.6% |
| GDP.pdf | — | 24% |
| METR Time Horizons | 85.2% | — |
| Vending-Bench 2 | — | 11,182 |

## Reasoning

- Claude Mythos Preview: —
- Claude Opus 5: 77.2 (#4)

| Benchmark | Claude Mythos Preview | Claude Opus 5 |
|---|---|---|
| ARC-AGI-2 | — | 90.4% |
| SimpleBench | — | 80.6% |
| NYT Connections (extended) | — | 94.3% |
| ARC-AGI-1 | — | 97.5% |
| CritPt | — | 29.1% |
| Chess Puzzles | — | 42% |
| EBR-Bench | — | 45.7% |
| LMArena Hard Prompts | — | 1526 |
| Mystery Game Puzzles | — | 59% |
| DTBench | — | 97.9% |
| LMCA | — | 64.5% |
| Bench to the Future 3 | — | 0.12 |
| Epoch Capabilities Index | — | 162.78 |

## Math

- Claude Mythos Preview: —
- Claude Opus 5: 86.2 (#8)

| Benchmark | Claude Mythos Preview | Claude Opus 5 |
|---|---|---|
| FrontierMath (Tiers 1-3) | — | 85.6% |
| FrontierMath Tier 4 | — | 73.2% |
| OTIS Mock AIME 2024-2025 | — | 98.9% |
| ProofBench | — | 99% |
| LMArena Math | — | 1531 |

## Knowledge

- Claude Mythos Preview: —
- Claude Opus 5: 66.8 (#9)

| Benchmark | Claude Mythos Preview | Claude Opus 5 |
|---|---|---|
| GPQA Diamond | — | 93.9% |
| SimpleQA Verified | — | 59.9% |
| LMArena Expert | — | 1557 |

## Multimodal

- Claude Mythos Preview: —
- Claude Opus 5: 50.8 (#8)

| Benchmark | Claude Mythos Preview | Claude Opus 5 |
|---|---|---|
| LMArena Vision | — | 1319 |
| Blueprint-Bench 2 | — | 30.4% |
| Furniture Assembly | — | 60.8% |
| LMArena Document | — | 1516 |

## Multilingual

- Claude Mythos Preview: —
- Claude Opus 5: 58.8 (#4)

| Benchmark | Claude Mythos Preview | Claude Opus 5 |
|---|---|---|
| LMArena Non-English | — | 1501 |
| LMArena Chinese | — | 1574 |
| LMArena French | — | 1519 |
| LMArena German | — | 1524 |
| LMArena Japanese | — | 1516 |
| LMArena Korean | — | 1521 |
| LMArena Russian | — | 1507 |
| LMArena Spanish | — | 1519 |

## Instruction Following

- Claude Mythos Preview: —
- Claude Opus 5: 79.2 (#7)

| Benchmark | Claude Mythos Preview | Claude Opus 5 |
|---|---|---|
| LMArena Instruction Following | — | 1517 |

## Long Context

- Claude Mythos Preview: —
- Claude Opus 5: 46.5 (#21)

| Benchmark | Claude Mythos Preview | Claude Opus 5 |
|---|---|---|
| LMArena Longer Query | — | 1515 |

## Writing & Preference

- Claude Mythos Preview: —
- Claude Opus 5: 79.2 (#1)

| Benchmark | Claude Mythos Preview | Claude Opus 5 |
|---|---|---|
| LMArena Text | — | 1507 |
| LMArena Creative Writing | — | 1491 |
| EQ-Bench Creative Writing | — | 2133 |
| EQ-Bench 4 | — | 1385 |
| LMArena Multi-Turn | — | 1499 |

## FAQ

### Is Claude Mythos Preview better than Claude Opus 5?

Claude Opus 5 has enough public results to be ranked (#4); Claude Mythos Preview does not yet, so treat this comparison as directional.

### How many benchmarks do Claude Mythos Preview and Claude Opus 5 share?

0 benchmarks have published results for both models. Claude Mythos Preview has 2 scored results on Noometry and Claude Opus 5 has 57.