# Claude Fable 5.1 vs DeepSeek V4.1 Flash

> Side-by-side benchmark comparison for Claude Fable 5.1 and DeepSeek V4.1 Flash across agentic, coding, multimodal, knowledge, reasoning, multilingual, and math tasks.

- Canonical page: https://benchlm.ai/compare/claude-fable-5-1-vs-deepseek-v4-1-flash
- Last updated: September 10, 2026

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

## Quick Verdict

Pick Claude Fable 5.1 if you want the stronger benchmark profile. DeepSeek V4.1 Flash 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 84.38 to 55.
- The biggest single benchmark swing is ProgramBench in Coding, with scores of 87.6% and 20.3%.
- DeepSeek V4.1 Flash 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 | DeepSeek V4.1 Flash |
|----------|----------|----------|
| Creator | Anthropic | DeepSeek |
| Type | Proprietary | Open Weight |
| Reasoning | Reasoning | Reasoning |
| Context | 1M | 1M |
| Overall Score | 84.38 | null |
| Benchmarks Covered | 24 | 21 |
| Pricing (input/output) | $10.00 / $50.00 | $0.30 / $1.20 |

## Category Breakdown

### Agentic

- Winner: Coming soon
- Claude Fable 5.1 public-lane score: 80.1 (Supported · #1/152)
- DeepSeek V4.1 Flash public-lane score: Coming soon

| Benchmark | Claude Fable 5.1 | DeepSeek V4.1 Flash | Winner |
|-----------|-----------|-----------|--------|
| Terminal-Bench 4.0 | 55.80% | 31.20% | 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% | 54.8% | DeepSeek V4.1 Flash |
| 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 |
| Terminal-Bench 2.1 | Coming soon | 90.6% | Coming soon |
| terminalBench3 | Coming soon | 30% | Coming soon |
| CyberGym | Coming soon | 88.1% | Coming soon |
| ExploitGym | Coming soon | 15.3% | Coming soon |
| HLE w/ tools | Coming soon | 63.9% | Coming soon |
| Agents' Last Exam | Coming soon | 31.8% | Coming soon |

### Coding

- Winner: Coming soon
- Claude Fable 5.1 public-lane score: 84.2 (Supported · #1/151)
- DeepSeek V4.1 Flash public-lane score: Coming soon

| Benchmark | Claude Fable 5.1 | DeepSeek V4.1 Flash | 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% | 74.2% | DeepSeek V4.1 Flash |
| FrontierSWE v2 | 56.3% | Coming soon | Coming soon |
| ProgramBench | 87.6% | 20.3% | Claude Fable 5.1 |
| cursorBench32 | 73.4% | Coming soon | Coming soon |
| LiveCodeBench (Vals) | 90.5% | Coming soon | Coming soon |
| Codeforces | Coming soon | 3471.0 | Coming soon |
| Terminal-Bench 2.1 | Coming soon | 90.6% | Coming soon |
| terminalBench3 | Coming soon | 30% | Coming soon |
| NL2Repo | Coming soon | 65.4% | Coming soon |

### Multimodal & Grounded

- Winner: Coming soon
- Claude Fable 5.1 public-lane score: Coming soon
- DeepSeek V4.1 Flash public-lane score: Coming soon

| Benchmark | Claude Fable 5.1 | DeepSeek V4.1 Flash | Winner |
|-----------|-----------|-----------|--------|
| Chartography (tools) | Coming soon | 78.9% | Coming soon |
| BabyVision w/ Python | Coming soon | 89.6% | Coming soon |
| ZeroBench w/ Python | Coming soon | 49.0% | Coming soon |

### Reasoning

- Winner: Coming soon
- Claude Fable 5.1 public-lane score: 79.4 (#2/18)
- DeepSeek V4.1 Flash public-lane score: Coming soon

| Benchmark | Claude Fable 5.1 | DeepSeek V4.1 Flash | Winner |
|-----------|-----------|-----------|--------|
| ARC-AGI-1 | 97.50% | Coming soon | Coming soon |
| ARC-AGI-2 | 90% | Coming soon | Coming soon |

### Knowledge

- Winner: Coming soon
- Claude Fable 5.1 public-lane score: 86.8 (Supported · #1/182)
- DeepSeek V4.1 Flash public-lane score: Coming soon

| Benchmark | Claude Fable 5.1 | DeepSeek V4.1 Flash | Winner |
|-----------|-----------|-----------|--------|
| HLE | 65% | 36.8% | Claude Fable 5.1 |
| 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 | Coming soon | 90.9% | Coming soon |
| GPQA-D | Coming soon | 90.9% | Coming soon |

### Mathematics

- Winner: Coming soon
- Claude Fable 5.1 public-lane score: Coming soon
- DeepSeek V4.1 Flash public-lane score: Coming soon

| Benchmark | Claude Fable 5.1 | DeepSeek V4.1 Flash | Winner |
|-----------|-----------|-----------|--------|
| Apex | Coming soon | 65.6% | Coming soon |

## FAQ

### Which is better overall, Claude Fable 5.1 or DeepSeek V4.1 Flash?

Claude Fable 5.1 is ahead overall on BenchLM right now.

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

Claude Fable 5.1 currently has 24 sourced benchmark scores on BenchLM.

### How many benchmarks does DeepSeek V4.1 Flash cover on BenchLM?

DeepSeek V4.1 Flash currently has 21 sourced benchmark scores on BenchLM.

## Related Comparisons

- [Claude Fable 5.1 vs Claude Fable 5](/compare/claude-fable-vs-claude-fable-5-1)
- [DeepSeek V4.1 Flash vs Claude Fable 5](/compare/claude-fable-vs-deepseek-v4-1-flash)
- [Claude Fable 5.1 vs GPT-6 Astra](/compare/claude-fable-5-1-vs-gpt-6-astra)
- [DeepSeek V4.1 Flash vs GPT-6 Astra](/compare/deepseek-v4-1-flash-vs-gpt-6-astra)

## Explore More

- [Claude Fable 5.1 profile](/models/claude-fable-5-1)
- [DeepSeek V4.1 Flash profile](/models/deepseek-v4-1-flash)
- [Compare Pricing](/llm-pricing)
- [Alternative Finder](/tools/alternative-finder)
- [LLM Selector](/tools/llm-selector)
- [Overall Rankings](/best/overall)