# Claude Fable 5.1 vs Gemini 4 Carbon

> Side-by-side benchmark comparison for Claude Fable 5.1 and Gemini 4 Carbon across agentic, coding, multimodal, knowledge, reasoning, multilingual, and math tasks.

- Canonical page: https://benchlm.ai/compare/claude-fable-5-1-vs-gemini-4-carbon
- Last updated: October 29, 2026

- Shared sourced benchmarks: 5
- HTML indexing: indexable
- Ranking lane: BenchAlign v5.8

## Quick Verdict

Gemini 4 Carbon leads by point estimate. Conditional score ranges do not establish rank confidence. Choose using the category evidence and your own workload tests.

## Summary

- Gemini 4 Carbon has the higher overall point estimate 88.37 to 81.07. Conditional score ranges do not establish rank confidence.
- The clearest category separation is in reasoning, where the averages are 85.2 for Claude Fable 5.1 and 79.5 for Gemini 4 Carbon.
- The biggest single benchmark swing is GraphWalks BFS 256K–1M in Reasoning, with scores of 65.0% and 96.2%.
- Gemini 4 Carbon is the cheaper option on output tokens, which matters if you expect large responses or heavy interactive use.
- Claude Fable 5.1 also has the larger context window at 1M.

## Model Snapshot

| Property | Claude Fable 5.1 | Gemini 4 Carbon |
|----------|----------|----------|
| Creator | Anthropic | Google |
| Type | Proprietary | Proprietary |
| Reasoning | Reasoning | Reasoning |
| Context | 1M | null |
| Overall Score | 81.07 | 88.37 |
| Benchmarks Covered | 36 | 9 |
| Pricing (input/output) | $10.00 / $50.00 | $2.00 / $10.00 |

## Category Breakdown

### Agentic

- Winner: Not comparable
- Claude Fable 5.1 public-lane score: 80.7 (Supported · #2/134)
- Gemini 4 Carbon public-lane score: Coming soon

| Benchmark | Claude Fable 5.1 | Gemini 4 Carbon | 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% | 53.9% | Gemini 4 Carbon |
| 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% | 71.0% | Gemini 4 Carbon |
| MazeBench | 10% | Coming soon | Coming soon |
| OSWorld 2.1 | 80.7% | Coming soon | Coming soon |
| OSWorld 2.1 Offline | Coming soon | 81.5% | Coming soon |
| ExploitGym | Coming soon | 53.5% | Coming soon |

### Coding

- Winner: Gemini 4 Carbon
- Claude Fable 5.1 public-lane score: 76.4 (Supported · #4/156)
- Gemini 4 Carbon public-lane score: 81.1 (Supported · #3/156)

| Benchmark | Claude Fable 5.1 | Gemini 4 Carbon | Winner |
|-----------|-----------|-----------|--------|
| Bug Hunt Bench | 43.0 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% | Coming soon | Coming soon |
| FrontierSWE v2 | 56.3% | 61.2% | Gemini 4 Carbon |
| 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 |
| FrontierCode 2.0 | 32.4% | Coming soon | Coming soon |

### Reasoning

- Winner: Not comparable
- Claude Fable 5.1 public-lane score: 85.2 (#5/26)
- Gemini 4 Carbon public-lane score: 79.5 (Unranked · 2 rankable rows)

| Benchmark | Claude Fable 5.1 | Gemini 4 Carbon | Winner |
|-----------|-----------|-----------|--------|
| ARC-AGI-1 | 97.50% | Coming soon | Coming soon |
| ARC-AGI-2 | 90% | Coming soon | Coming soon |
| GraphWalks BFS 256K–1M | 65.0% | 96.2% | Gemini 4 Carbon |

### Multimodal & Grounded

- Winner: Not comparable
- Claude Fable 5.1 public-lane score: Coming soon
- Gemini 4 Carbon public-lane score: Coming soon

| Benchmark | Claude Fable 5.1 | Gemini 4 Carbon | Winner |
|-----------|-----------|-----------|--------|
| ParseBench | 78.12% | Coming soon | Coming soon |
| Chartography (no tools) | Coming soon | 72.5% | Coming soon |
| Blueprint-Bench 2 | Coming soon | 58.6% | Coming soon |

### Knowledge

- Winner: Gemini 4 Carbon
- Claude Fable 5.1 public-lane score: 86 (Supported · #4/178)
- Gemini 4 Carbon public-lane score: 88.2 (Supported · #2/178)

| Benchmark | Claude Fable 5.1 | Gemini 4 Carbon | 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 |

### Instruction Following

- Winner: Not comparable
- Claude Fable 5.1 public-lane score: Coming soon
- Gemini 4 Carbon public-lane score: Coming soon

| Benchmark | Claude Fable 5.1 | Gemini 4 Carbon | Winner |
|-----------|-----------|-----------|--------|
| Gray Swan IPI (15 attempts) | 1.0% | 0.0% | Gemini 4 Carbon |

### Mathematics

- Winner: Not comparable
- Claude Fable 5.1 public-lane score: 96.8 (Unranked · 2 rankable rows)
- Gemini 4 Carbon public-lane score: Coming soon

| Benchmark | Claude Fable 5.1 | Gemini 4 Carbon | Winner |
|-----------|-----------|-----------|--------|
| FrontierMath v2 (Tiers 1-3) | 90.175% | Coming soon | Coming soon |
| FrontierMath v2 (Tier 4) | 87.805% | Coming soon | Coming soon |

## FAQ

### Which is better overall, Claude Fable 5.1 or Gemini 4 Carbon?

Gemini 4 Carbon has the higher overall point estimate. Conditional score ranges do not establish rank confidence.

### Where is the biggest gap between Claude Fable 5.1 and Gemini 4 Carbon?

The widest category gap is in reasoning, where the averages are 85.2 for Claude Fable 5.1 and 79.5 for Gemini 4 Carbon.

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

Claude Fable 5.1 currently has 36 sourced benchmark scores on BenchLM.

### How many benchmarks does Gemini 4 Carbon cover on BenchLM?

Gemini 4 Carbon currently has 9 sourced benchmark scores on BenchLM.

## Related Comparisons

- [Claude Fable 5.1 vs Claude Fable 5](/compare/claude-fable-vs-claude-fable-5-1)
- [Gemini 4 Carbon vs Claude Fable 5](/compare/claude-fable-vs-gemini-4-carbon)
- [Claude Fable 5.1 vs Gemini 4 Argon](/compare/claude-fable-5-1-vs-gemini-4-argon)
- [Gemini 4 Carbon vs Gemini 4 Argon](/compare/gemini-4-argon-vs-gemini-4-carbon)

## Explore More

- [Claude Fable 5.1 profile](/models/claude-fable-5-1)
- [Gemini 4 Carbon profile](/models/gemini-4-carbon)
- [Compare Pricing](/llm-pricing)
- [Alternative Finder](/tools/alternative-finder)
- [LLM Selector](/tools/llm-selector)
- [Overall Rankings](/best/overall)