Claude Fable 5 vs Claude Opus 5
Vals Science Index?
Fable 5—
Opus 547.9
| Benchmark | Fable 5 | Opus 5 |
|---|---|---|
| Humanity's Last Exam | 55.5 | 51.3 |
| Arena Text · overall | 1,504 · high | 1,490 · max |
| Arena Text · Chinese | 1,543.5 · high | 1,573.1 · max |
| Arena Text · English | 1,497.6 · high | 1,508.1 · max |
| Arena Text · French | 1,506.1 · high | 1,518.4 · high |
| Arena Text · German | 1,484.9 · high | 1,530.1 · max |
| Arena Text · instruction following | 1,501.6 · high | 1,518.4 · max |
| Arena Text · Japanese | 1,506.5 · high | 1,520.5 · max |
| Arena Text · Korean | 1,487.7 · high | 1,518.1 · max |
| Arena Text · non-English | 1,481.4 · high | 1,501.3 · max |
| Arena Text · Polish | 1,490.1 · high | 1,522.9 · max |
| Arena Text · Russian | 1,502.8 · high | 1,507.9 · max |
| Arena Text · Spanish | 1,495.2 · high | 1,522 · max |
| AA Omniscience Index | 43.3 | 31 |
| SimpleQA Verified v1 | 70.7 · xhigh | 63.3 |
| CritPt (physics) | 28.6 | 26.9 |
| AA Intelligence Index 4.3.2 | 49.6 | 44.8 |
| AA Omniscience · Accuracy | 65.4 | 57.1 |
| AA Omniscience · Hallucination Rate | 63.6 | 60.7 |
| AA-LCR (long context) 1.1 | 82.3 | 82 |
| GDP.pdf · AA all-pass | 24 | 20 |
| MLCR-AA | 20.6 | 13.9 |
| ARC-AGI-1 · public evaluation | 97.6 | 99 · max |
| ARC-AGI-1 · semi-private | 98.5 | 97.5 · max |
| ARC-AGI-2 · public evaluation | 96.4 | 97.1 · max |
| ARC-AGI-2 · semi-private | 89.2 | 90.4 · max |
| Chess Puzzles | 47 | 43 · max |
| FrontierMath Erdos | 0 | 0 · max |
| FrontierMath Tier 4 (v2) | 90.2 | 73.2 · max |
| FrontierMath Tiers 1–3 (v2) | 87 | 85.6 · max |
| Mystery Game Puzzles | 52 | 59 · max |
| MathArena · ArXivMath · June 2026 | 85.4 | 82.6 · max |
| MathArena · BrokenArXiv · June 2026 | 47.8 | 90.7 · max |
| MathArena · ArXivLean · June 2026 | 15.2 | 32.6 · max |
| Vals LegalBench | 88.6 | 87 |
| Vals MedCode | 56.1 | 63.6 |
| Vals MedScribe | 88.5 | 91 |
| Vals Legal Research Bench | 49.5 | 55.3 |
| IFBench (instructions) | 63.5 | — |
| ARC-AGI-3 · semi-private | — | 30.2 · high |
| EQ-Bench 3 | 2,096.4 | — |
| MathArena · ArXivMath · April 2026 | 72.5 | — |
| MathArena · ArXivMath · May 2026 | 87.5 | — |
| MathArena · BrokenArXiv · April 2026 | 54.1 | — |
| MathArena · BrokenArXiv · May 2026 | 44.5 | — |
| Vals Science Index | — | 47.9 |
Specs
| Spec | Fable 5 | Opus 5 |
|---|---|---|
| Input, per 1M | $10 | $5 |
| Output, per 1M | $50 | $25 |
| Cost per task? | $8.75 | $2.19 |
| Speed, tok/s | 67 | 51 |
| Context | 1M | 1M |
| Weights | Closed | Closed |
| Released | Jun 2026 | Jul 2026 |
| See images | ✓ | ✓ |
| Read PDFs | Partial | Partial |
| Hear audio | — | — |
| Watch video | — | — |
| Call tools | ✓ | ✓ |
| Force a tool call | Partial | Partial |
| Return strict JSON | ✓ | ✓ |
| Search the web | ? | ? |
| Run code | ? | ? |
| Use a computer | ? | ? |
What breaks when you switch
Fable 5 → Opus 5
Nothing known.
Opus 5 → Fable 5
Nothing known.