# Claude Fable 5.2 vs Gemini 3.8 Flash

> Side-by-side benchmark comparison for Claude Fable 5.2 and Gemini 3.8 Flash across agentic, coding, multimodal, knowledge, reasoning, multilingual, and math tasks.

- Canonical page: https://benchlm.ai/compare/claude-fable-5-2-vs-gemini-3-8-flash
- Last updated: November 9, 2026

- Shared sourced benchmarks: 6
- HTML indexing: indexable
- Ranking lane: BenchAlign v5.8

## Quick Verdict

Claude Fable 5.2 leads by point estimate. Conditional score ranges do not establish rank confidence. Choose using the category evidence and your own workload tests.

## Summary

- Claude Fable 5.2 has the higher overall point estimate 91.19 to 66.61. Conditional score ranges do not establish rank confidence.
- The clearest category separation is in knowledge, where the averages are 97.6 for Claude Fable 5.2 and 69.1 for Gemini 3.8 Flash.
- The biggest single benchmark swing is ARC-AGI-3 Provider Adapter in Reasoning, with scores of 94.90% and 35.00%.
- Gemini 3.8 Flash is the cheaper option on output tokens, which matters if you expect large responses or heavy interactive use.

## Model Snapshot

| Property | Claude Fable 5.2 | Gemini 3.8 Flash |
|----------|----------|----------|
| Creator | Anthropic | Google |
| Type | Proprietary | Proprietary |
| Reasoning | Reasoning | Reasoning |
| Context | 1M | 1M |
| Overall Score | 91.19 | 66.61 |
| Benchmarks Covered | 30 | 36 |
| Pricing (input/output) | $8.00 / $40.00 | $0.75 / $3.75 |

## Category Breakdown

### Agentic

- Winner: Directional only
- Claude Fable 5.2 public-lane score: 90.7 (Estimated · #1/132)
- Gemini 3.8 Flash public-lane score: 64.7 (Supported · #17/132)

| Benchmark | Claude Fable 5.2 | Gemini 3.8 Flash | Winner |
|-----------|-----------|-----------|--------|
| Terminal-Bench 4.0 | 67.60% | 19.10% | Claude Fable 5.2 |
| Terminal-Bench-Science 0.1 | 74.6% | Coming soon | Coming soon |
| AutomationBench | 51.4% | Coming soon | Coming soon |
| OSWorld 2.1 Offline | 89.3% | Coming soon | Coming soon |
| WANDR | 82.1% | Coming soon | Coming soon |
| Remote Labor Index | 41.3% | Coming soon | Coming soon |
| RoboDojo Sim | 64.9% | Coming soon | Coming soon |
| DRACO | 87.7% | Coming soon | Coming soon |
| Terminal-Bench 4.1 | Coming soon | 18.20% | Coming soon |
| Finance Agent v2 | Coming soon | 61.4% | Coming soon |
| Terminal-Bench 2.1 | Coming soon | 89.4% | Coming soon |
| OSWorld 2.0 | Coming soon | 59.0% | Coming soon |
| Terminal-Bench 2.1 (Vals) | Coming soon | 81.3% | Coming soon |
| ApprenticeBench | Coming soon | 24% | Coming soon |
| Hermes Index | Coming soon | 38.1% | Coming soon |
| Hermes Bench | Coming soon | 62.2% | Coming soon |
| MazeBench | Coming soon | 4% | Coming soon |

### Coding

- Winner: Directional only
- Claude Fable 5.2 public-lane score: 86.9 (Estimated · #1/158)
- Gemini 3.8 Flash public-lane score: 59.9 (Supported · #20/158)

| Benchmark | Claude Fable 5.2 | Gemini 3.8 Flash | Winner |
|-----------|-----------|-----------|--------|
| SWE-bench Pro | 93% | Coming soon | Coming soon |
| SWE Multilingual | 96.6% | Coming soon | Coming soon |
| SWE Multimodal | 74.1% | Coming soon | Coming soon |
| DeepSWE | 74.3% | 73.8% | Claude Fable 5.2 |
| FrontierSWE v2 | 69.9% | 19.6% | Claude Fable 5.2 |
| ProgramBench | 85.6% | Coming soon | Coming soon |
| FrontierCode 2.0 | 49.1% | Coming soon | Coming soon |
| CursorBench 4.0 | 60.0% | 39.6% | Claude Fable 5.2 |
| ScarfBench | Coming soon | 66.0% | Coming soon |
| Terminal-Bench 2.1 | Coming soon | 89.4% | Coming soon |
| CursorBench 3.2 | Coming soon | 69.2% | Coming soon |
| LiveCodeBench (Vals) | Coming soon | 89.5% | Coming soon |
| SWE-bench (Vals) | Coming soon | 80.0% | Coming soon |
| Bug Hunt Bench | Coming soon | 18.0 fixes | Coming soon |

### Reasoning

- Winner: Claude Fable 5.2
- Claude Fable 5.2 public-lane score: 90.7 (Supported · #1/157)
- Gemini 3.8 Flash public-lane score: 64.5 (Supported · #23/157)

| Benchmark | Claude Fable 5.2 | Gemini 3.8 Flash | Winner |
|-----------|-----------|-----------|--------|
| ARC-AGI-3 | 65.7% | 10.4% | Claude Fable 5.2 |
| ARC-AGI-3 Provider Adapter | 94.90% | 35.00% | Claude Fable 5.2 |
| STEM Professor Bench | 61.8% | Coming soon | Coming soon |
| ARC-AGI-1 | Coming soon | 98.50% | Coming soon |
| ARC-AGI-2 | Coming soon | 89.2% | Coming soon |

### Multimodal & Grounded

- Winner: Directional only
- Claude Fable 5.2 public-lane score: 89.8 (Estimated · #1/67)
- Gemini 3.8 Flash public-lane score: 70.3 (Supported · #13/67)

| Benchmark | Claude Fable 5.2 | Gemini 3.8 Flash | Winner |
|-----------|-----------|-----------|--------|
| Chartography (no tools) | 73.4% | Coming soon | Coming soon |
| Chartography (tools) | 91.6% | Coming soon | Coming soon |
| OfficeQA | 83.4% | Coming soon | Coming soon |
| OfficeQA Pro | 72.9% | Coming soon | Coming soon |
| BenchCAD 2.1 | 75.4% | Coming soon | Coming soon |
| BenchCAD 2.1 (tools) | 83.5% | Coming soon | Coming soon |
| ExtractBench (LlamaIndex) | Coming soon | 80.71% | Coming soon |
| ParseBench | Coming soon | 71.20% | Coming soon |
| CharXiv w/o tools | Coming soon | 86.2% | Coming soon |
| LVBench | Coming soon | 87.1% | Coming soon |

### Knowledge

- Winner: Claude Fable 5.2
- Claude Fable 5.2 public-lane score: 97.6 (Supported · #1/179)
- Gemini 3.8 Flash public-lane score: 69.1 (Supported · #18/179)

| Benchmark | Claude Fable 5.2 | Gemini 3.8 Flash | Winner |
|-----------|-----------|-----------|--------|
| HLE | 74.2% | Coming soon | Coming soon |
| HLE w/o tools | 73.2% | Coming soon | Coming soon |
| PhysicianBench | 64.4% | Coming soon | Coming soon |
| HLE-Verified | Coming soon | 54.9% | Coming soon |
| LABBench2 | Coming soon | 86.2% | Coming soon |
| BioMysteryBench (human-solvable) | Coming soon | 88.8% | Coming soon |
| BioMysteryBench (human-difficult) | Coming soon | 56.5% | Coming soon |
| GPQA Diamond (Vals) | Coming soon | 94.4% | Coming soon |
| MMLU-Pro (Vals) | Coming soon | 90.2% | Coming soon |

### Multilingual

- Winner: Not comparable
- Claude Fable 5.2 public-lane score: Coming soon
- Gemini 3.8 Flash public-lane score: Coming soon

| Benchmark | Claude Fable 5.2 | Gemini 3.8 Flash | Winner |
|-----------|-----------|-----------|--------|
| GMMLU | 96.0% | Coming soon | Coming soon |
| MILU | 94.1% | Coming soon | Coming soon |

### Instruction Following

- Winner: Not comparable
- Claude Fable 5.2 public-lane score: Coming soon
- Gemini 3.8 Flash public-lane score: Coming soon

| Benchmark | Claude Fable 5.2 | Gemini 3.8 Flash | Winner |
|-----------|-----------|-----------|--------|
| Gray Swan IPI (15 attempts) | Coming soon | 5.5% | Coming soon |

### Mathematics

- Winner: Not comparable
- Claude Fable 5.2 public-lane score: Coming soon
- Gemini 3.8 Flash public-lane score: 66.2 (Unranked · 2 rankable rows)

| Benchmark | Claude Fable 5.2 | Gemini 3.8 Flash | Winner |
|-----------|-----------|-----------|--------|
| FrontierMath v2 (Tiers 1-3) | Coming soon | 68.421% | Coming soon |
| FrontierMath v2 (Tier 4) | Coming soon | 21.951% | Coming soon |

## FAQ

### Which is better overall, Claude Fable 5.2 or Gemini 3.8 Flash?

Claude Fable 5.2 has the higher overall point estimate. Conditional score ranges do not establish rank confidence.

### Where is the biggest gap between Claude Fable 5.2 and Gemini 3.8 Flash?

The widest category gap is in knowledge, where the averages are 97.6 for Claude Fable 5.2 and 69.1 for Gemini 3.8 Flash.

### How many benchmarks does Claude Fable 5.2 cover on BenchLM?

Claude Fable 5.2 currently has 30 sourced benchmark scores on BenchLM.

### How many benchmarks does Gemini 3.8 Flash cover on BenchLM?

Gemini 3.8 Flash currently has 36 sourced benchmark scores on BenchLM.

## Related Comparisons

- [Claude Fable 5.2 vs Claude Fable 5.1](/compare/claude-fable-5-1-vs-claude-fable-5-2)
- [Gemini 3.8 Flash vs Claude Fable 5.1](/compare/claude-fable-5-1-vs-gemini-3-8-flash)
- [Claude Fable 5.2 vs Claude Fable 5](/compare/claude-fable-vs-claude-fable-5-2)
- [Gemini 3.8 Flash vs Claude Fable 5](/compare/claude-fable-vs-gemini-3-8-flash)

## Explore More

- [Claude Fable 5.2 profile](/models/claude-fable-5-2)
- [Gemini 3.8 Flash profile](/models/gemini-3-8-flash)
- [Compare Pricing](/llm-pricing)
- [Alternative Finder](/tools/alternative-finder)
- [LLM Selector](/tools/llm-selector)
- [Overall Rankings](/best/overall)