# Claude Fable 5.1 vs Pareto 26.10 Preview

> Side-by-side benchmark comparison for Claude Fable 5.1 and Pareto 26.10 Preview across agentic, coding, multimodal, knowledge, reasoning, multilingual, and math tasks.

- Canonical page: https://benchlm.ai/compare/claude-fable-5-1-vs-pareto-26-10-preview
- Last updated: October 1, 2026

- Shared sourced benchmarks: 2
- HTML indexing: indexable
- Ranking lane: BenchAlign v5.8

## Quick Verdict

Evidence is too thin for a benchmark verdict: Claude Fable 5.1 and Pareto 26.10 Preview share only 2 sourced benchmark rows.

## Summary

- Only 2 shared sourced benchmark rows are available. That is not enough for a broad capability verdict, so this mirror does not name an overall winner.
- Pareto 26.10 Preview has the lower published output-token price.
- Claude Fable 5.1 has the larger published context window at 1M.

## Model Snapshot

| Property | Claude Fable 5.1 | Pareto 26.10 Preview |
|----------|----------|----------|
| Creator | Anthropic | Unbiased |
| Type | Proprietary | Proprietary |
| Reasoning | Reasoning | Reasoning |
| Context | 1M | N/A |
| Independent public score (not head-to-head) | 82.82 | null |
| Benchmarks Covered | 30 | 3 |
| Pricing (input/output) | $10.00 / $50.00 | $2.50 / $7.50 |

## Category Breakdown

### Agentic

- Winner: Insufficient shared evidence
- Claude Fable 5.1 public-lane score: 78.9 (Supported · #2/119)
- Pareto 26.10 Preview public-lane score: Coming soon

| Benchmark | Claude Fable 5.1 | Pareto 26.10 Preview | Winner |
|-----------|-----------|-----------|--------|
| Terminal-Bench 4.0 | 55.80% | 50.80% | Claude Fable 5.1 |
| Terminal-Bench-Science 0.1 | 52.6% | Coming soon | Coming soon |
| OSWorld 2.0 | 41.7% | Coming soon | Coming soon |
| AutomationBench | 31.4% | Coming soon | Coming soon |
| Toolathlon-Verified | 77.8% | Coming soon | Coming soon |
| Toolathlon Verified Pass@3 | 81.5% | Coming soon | Coming soon |
| Toolathlon Verified Pass³ | 73.1% | Coming soon | Coming soon |
| Toolathlon Verified avg. turns | 23.7 turns | Coming soon | Coming soon |
| Terminal-Bench 2.1 (Vals) | 85.0% | Coming soon | Coming soon |
| ApprenticeBench | 72% | Coming soon | Coming soon |
| CWE-bench v1 | 58.0% | Coming soon | Coming soon |

### Coding

- Winner: Insufficient shared evidence
- Claude Fable 5.1 public-lane score: 79.8 (Supported · #3/144)
- Pareto 26.10 Preview public-lane score: Coming soon

| Benchmark | Claude Fable 5.1 | Pareto 26.10 Preview | Winner |
|-----------|-----------|-----------|--------|
| Bug Hunt Bench | 43 fixes | Coming soon | Coming soon |
| SWE-bench Pro | 81.2% | Coming soon | Coming soon |
| SWE Multilingual | 89.1% | Coming soon | Coming soon |
| SWE Multimodal | 54.7% | Coming soon | Coming soon |
| DeepSWE | 67.4% | 69.9% | Pareto 26.10 Preview |
| FrontierSWE v2 | 56.3% | Coming soon | Coming soon |
| ProgramBench | 87.6% | Coming soon | Coming soon |
| CursorBench 3.2 | 73.4% | Coming soon | Coming soon |
| LiveCodeBench (Vals) | 90.5% | Coming soon | Coming soon |
| CursorBench 4.0 | 51.8% | Coming soon | Coming soon |
| PostTrainBench v1.1 | 40.2% | Coming soon | Coming soon |

### Reasoning

- Winner: Insufficient shared evidence
- Claude Fable 5.1 public-lane score: 81.4 (#3/27)
- Pareto 26.10 Preview public-lane score: Coming soon

| Benchmark | Claude Fable 5.1 | Pareto 26.10 Preview | Winner |
|-----------|-----------|-----------|--------|
| ARC-AGI-1 | 97.50% | Coming soon | Coming soon |
| ARC-AGI-2 | 90% | Coming soon | Coming soon |
| GraphWalks BFS 256K–1M | 65.0% | Coming soon | Coming soon |

### Knowledge

- Winner: Insufficient shared evidence
- Claude Fable 5.1 public-lane score: 84.9 (Supported · #3/170)
- Pareto 26.10 Preview public-lane score: Coming soon

| Benchmark | Claude Fable 5.1 | Pareto 26.10 Preview | Winner |
|-----------|-----------|-----------|--------|
| HLE | 65% | Coming soon | Coming soon |
| HLE w/o tools | 60.9% | Coming soon | Coming soon |
| GPQA Diamond (Vals) | 93.4% | Coming soon | Coming soon |
| MMLU-Pro (Vals) | 92.4% | Coming soon | Coming soon |
| GPQA-D | Coming soon | 92.4% | Coming soon |

### Instruction Following

- Winner: Insufficient shared evidence
- Claude Fable 5.1 public-lane score: Coming soon
- Pareto 26.10 Preview public-lane score: Coming soon

| Benchmark | Claude Fable 5.1 | Pareto 26.10 Preview | Winner |
|-----------|-----------|-----------|--------|
| Gray Swan IPI (15 attempts) | 1.0% | Coming soon | Coming soon |

## FAQ

### Is there enough evidence to pick between Claude Fable 5.1 and Pareto 26.10 Preview?

Not yet. The models share only 2 sourced benchmark rows, so this mirror reports the available measurements and metadata without naming a broad winner.

### What can I compare safely on this page?

Published pricing, context windows, model type, and individual shared benchmark rows are directly comparable. Independent overall scores and non-overlapping benchmark coverage are labeled separately and should not be read as a controlled head-to-head result.

## Related Comparisons

- [Claude Fable 5.1 vs Claude Fable 5](/compare/claude-fable-vs-claude-fable-5-1)
- [Pareto 26.10 Preview vs Claude Fable 5](/compare/claude-fable-vs-pareto-26-10-preview)
- [Claude Fable 5.1 vs Pareto 26.9](/compare/claude-fable-5-1-vs-pareto-26-9)
- [Pareto 26.10 Preview vs Pareto 26.9](/compare/pareto-26-10-preview-vs-pareto-26-9)

## Explore More

- [Claude Fable 5.1 profile](/models/claude-fable-5-1)
- [Pareto 26.10 Preview profile](/models/pareto-26-10-preview)
- [Compare Pricing](/llm-pricing)
- [Alternative Finder](/tools/alternative-finder)
- [LLM Selector](/tools/llm-selector)
- [Overall Rankings](/best/overall)