# Claude Fable 5.1 vs Inkling-Small

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

- Canonical page: https://benchlm.ai/compare/claude-fable-5-1-vs-inkling-small
- Last updated: October 17, 2026

- Shared sourced benchmarks: 12
- HTML indexing: indexable
- Ranking lane: BenchAlign v5.8

## Quick Verdict

Pick Claude Fable 5.1 if you want the stronger benchmark profile. Inkling-Small only makes more sense when its price, context window, or workload-specific category wins matter more than the overall score.

## Summary

- Claude Fable 5.1 leads overall 83.18 to 53.5.
- The clearest category separation is in agentic, where the averages are 80.9 for Claude Fable 5.1 and 36.8 for Inkling-Small.
- The biggest single benchmark swing is FrontierMath v2 (Tier 4) in Mathematics, with scores of 87.805% and 17.073%.
- Inkling-Small is the cheaper option on output tokens, which matters if you expect large responses or heavy interactive use.

## Model Snapshot

| Property | Claude Fable 5.1 | Inkling-Small |
|----------|----------|----------|
| Creator | Anthropic | Thinking Machines Lab |
| Type | Proprietary | Open Weight |
| Reasoning | Reasoning | Hybrid |
| Context | 1M | 1M |
| Overall Score | 83.18 | 53.5 |
| Benchmarks Covered | 33 | 28 |
| Pricing (input/output) | $10.00 / $50.00 | $0.58 / $1.44 |

## Category Breakdown

### Agentic

- Winner: Claude Fable 5.1
- Claude Fable 5.1 public-lane score: 80.9 (Supported · #2/128)
- Inkling-Small public-lane score: 36.8 (Supported · #77/128)

| Benchmark | Claude Fable 5.1 | Inkling-Small | Winner |
|-----------|-----------|-----------|--------|
| Terminal-Bench 4.0 | 55.80% | Coming soon | Coming soon |
| 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% | 54.4% | Claude Fable 5.1 |
| 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% | 55.1% | Claude Fable 5.1 |
| ApprenticeBench | 72% | Coming soon | Coming soon |
| CWE-bench v1 | 58.0% | Coming soon | Coming soon |
| MazeBench | 10% | Coming soon | Coming soon |
| Terminal-Bench 2.1 | Coming soon | 64.7% | Coming soon |
| BrowseComp | Coming soon | 77.4% | Coming soon |
| MCP Atlas | Coming soon | 79.6% | Coming soon |

### Coding

- Winner: Claude Fable 5.1
- Claude Fable 5.1 public-lane score: 76.8 (Supported · #3/150)
- Inkling-Small public-lane score: 37.7 (Supported · #71/150)

| Benchmark | Claude Fable 5.1 | Inkling-Small | Winner |
|-----------|-----------|-----------|--------|
| Bug Hunt Bench | 43.0 fixes | Coming soon | Coming soon |
| SWE-bench Pro | 81.2% | 55.9% | Claude Fable 5.1 |
| SWE Multilingual | 89.1% | Coming soon | Coming soon |
| SWE Multimodal | 54.7% | Coming soon | Coming soon |
| DeepSWE | 67.4% | Coming soon | Coming soon |
| 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% | 85.9% | Claude Fable 5.1 |
| CursorBench 4.0 | 51.8% | Coming soon | Coming soon |
| PostTrainBench v1.1 | 40.2% | Coming soon | Coming soon |
| SWE-bench Verified | Coming soon | 80.2% | Coming soon |
| Terminal-Bench 2.1 | Coming soon | 64.7% | Coming soon |
| SciCode | Coming soon | 48.7% | Coming soon |
| SWE-bench (Vals) | Coming soon | 82.2% | Coming soon |

### Reasoning

- Winner: Not comparable
- Claude Fable 5.1 public-lane score: 85.2 (#4/28)
- Inkling-Small public-lane score: 55 (Unranked · 4 rankable rows)

| Benchmark | Claude Fable 5.1 | Inkling-Small | Winner |
|-----------|-----------|-----------|--------|
| ARC-AGI-1 | 97.50% | 84.00% | Claude Fable 5.1 |
| ARC-AGI-2 | 90% | 40.1% | Claude Fable 5.1 |
| GraphWalks BFS 256K–1M | 65.0% | Coming soon | Coming soon |
| CritPt | Coming soon | 8.3% | Coming soon |

### Multimodal & Grounded

- Winner: Not comparable
- Claude Fable 5.1 public-lane score: Coming soon
- Inkling-Small public-lane score: 67.5 (#36/54)

| Benchmark | Claude Fable 5.1 | Inkling-Small | Winner |
|-----------|-----------|-----------|--------|
| MMMU-Pro | Coming soon | 74% | Coming soon |
| CharXiv | Coming soon | 81.3% | Coming soon |
| CharXiv w/o tools | Coming soon | 77.4% | Coming soon |

### Knowledge

- Winner: Claude Fable 5.1
- Claude Fable 5.1 public-lane score: 86.9 (Supported · #2/184)
- Inkling-Small public-lane score: 55.1 (Supported · #59/184)

| Benchmark | Claude Fable 5.1 | Inkling-Small | Winner |
|-----------|-----------|-----------|--------|
| HLE | 65% | 47.8% | Claude Fable 5.1 |
| HLE w/o tools | 60.9% | 31.6% | Claude Fable 5.1 |
| GPQA Diamond (Vals) | 93.4% | 83.6% | Claude Fable 5.1 |
| MMLU-Pro (Vals) | 92.4% | 85.6% | Claude Fable 5.1 |
| GPQA | Coming soon | 89.5% | Coming soon |
| GPQA-D | Coming soon | 89.5% | Coming soon |

### Instruction Following

- Winner: Not comparable
- Claude Fable 5.1 public-lane score: Coming soon
- Inkling-Small public-lane score: 93.3 (#9/148)

| Benchmark | Claude Fable 5.1 | Inkling-Small | Winner |
|-----------|-----------|-----------|--------|
| Gray Swan IPI (15 attempts) | 1.0% | Coming soon | Coming soon |
| IFBench | Coming soon | 82.2% | Coming soon |

### Mathematics

- Winner: Not comparable
- Claude Fable 5.1 public-lane score: 96.8 (Unranked · 2 rankable rows)
- Inkling-Small public-lane score: 69.8 (#5/12)

| Benchmark | Claude Fable 5.1 | Inkling-Small | Winner |
|-----------|-----------|-----------|--------|
| FrontierMath v2 (Tiers 1-3) | 90.175% | 46.316% | Claude Fable 5.1 |
| FrontierMath v2 (Tier 4) | 87.805% | 17.073% | Claude Fable 5.1 |
| AIME26 | Coming soon | 95.5% | Coming soon |
| HMMT Feb 2026 | Coming soon | 90.2% | Coming soon |

## FAQ

### Which is better overall, Claude Fable 5.1 or Inkling-Small?

Claude Fable 5.1 is ahead overall on BenchLM right now.

### Where is the biggest gap between Claude Fable 5.1 and Inkling-Small?

The widest category gap is in agentic, where the averages are 80.9 for Claude Fable 5.1 and 36.8 for Inkling-Small.

### How many benchmarks does Claude Fable 5.1 cover on BenchLM?

Claude Fable 5.1 currently has 33 sourced benchmark scores on BenchLM.

### How many benchmarks does Inkling-Small cover on BenchLM?

Inkling-Small currently has 28 sourced benchmark scores on BenchLM.

## Related Comparisons

- [Claude Fable 5.1 vs Claude Fable 5](/compare/claude-fable-vs-claude-fable-5-1)
- [Inkling-Small vs Claude Fable 5](/compare/claude-fable-vs-inkling-small)
- [Claude Fable 5.1 vs Inkling](/compare/claude-fable-5-1-vs-inkling)
- [Inkling-Small vs Inkling](/compare/inkling-vs-inkling-small)

## Explore More

- [Claude Fable 5.1 profile](/models/claude-fable-5-1)
- [Inkling-Small profile](/models/inkling-small)
- [Compare Pricing](/llm-pricing)
- [Alternative Finder](/tools/alternative-finder)
- [LLM Selector](/tools/llm-selector)
- [Overall Rankings](/best/overall)