Claude Fable 5.1 vs Step 5 Preview
Claude Fable 5.1 
Step 5 Preview Verdict
- Claude Fable 5.1 (high) leads on quality: 72.0 vs 65.0.
- Claude Fable 5.1 (high) is stronger in agents & tools, coding, composite, knowledge.
- Step 5 Preview is stronger in long context, reasoning, multimodal.
- Step 5 Preview is 14× cheaper ($1.43 vs $20.00 per 1M blended).
| Metric | Claude Fable 5.1 (high) | Step 5 Preview |
|---|---|---|
| BenchLeader Index | 72.0 | 65.0 |
| Agents & tools score | 66.6 | – |
| Coding score | 74.1 | – |
| Composite score | 94.0 | 84.4 |
| Knowledge score | 83.7 | 72.0 |
| Long context score | 68.4 | 70.8 |
| Reasoning score | 81.0 | 82.1 |
| Multimodal score | – | 60.8 |
| Blended price $/M | $20.00 | $1.43 |
| Output speed | 55 tok/s | – |
| Time to first answer | 14.7 s | – |
| Context window | 1M | 1M |
| Terminal-Bench | 54.5% | – |
| SciCode | 57.6% | – |
| WeirdML | 92.3% | – |
| APEX-Agents | 44.4% | – |
| AA Intelligence Index | 51.2 | 43.6 |
| AA-LCR | 83.7% | 88.3% |
| MMMU-Pro | – | 76.4% |
| AA-Omniscience | 40.8 | 16.4 |
| GPQA Diamond (AA) | 90.6% | – |
| Humanity's Last Exam (AA) | 55.9% | 46.5% |
| SciCode (AA) | 58.7% | 58.9% |
| ARC-AGI-1 | 96.0% | – |
| ARC-AGI-2 | 88.8% | – |
| CritPt | 30.3% | 20.9% |
| GDPval (AA) | 57.5% | 53.6% |
| τ²-Bench Banking (AA) | 43.1% | – |
| MirrorCode | 73.3% | – |
| CursorBench | 69.4% | – |
| ALE-Bench | 2143.2 | – |
Data as of 2026-09-19. Best configuration of each model; every score links to its source on the model pages.
Claude Fable 5.1 vs Step 5 Preview: questions
- Is Claude Fable 5.1 better than Step 5 Preview?
- Claude Fable 5.1 (high) leads on quality: 72.0 vs 65.0. The BenchLeader Index combines every independent quality benchmark; Claude Fable 5.1 (high) is ahead overall as of 2026-09-19, but check the category scores for your use.
- Which is cheaper, Claude Fable 5.1 or Step 5 Preview?
- Step 5 Preview is cheaper: $1.43 against $20.00 per million tokens, blended at three input tokens per output token.
- Which has the larger context window?
- Both accept 1M tokens of context.