# Claude Fable 5.2 vs GPT-5.6 Terra

> Side-by-side benchmark comparison for Claude Fable 5.2 and GPT-5.6 Terra across agentic, coding, multimodal, knowledge, reasoning, multilingual, and math tasks.

- Canonical page: https://benchlm.ai/compare/claude-fable-5-2-vs-gpt-5-6-terra
- Last updated: November 9, 2026

- Shared sourced benchmarks: 4
- 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 69.42. Conditional score ranges do not establish rank confidence.
- The clearest category separation is in agentic, where the averages are 90.7 for Claude Fable 5.2 and 60.4 for GPT-5.6 Terra.
- The biggest single benchmark swing is ARC-AGI-3 in Reasoning, with scores of 65.7% and 0.8%.
- GPT-5.6 Terra is the cheaper option on output tokens, which matters if you expect large responses or heavy interactive use.
- GPT-5.6 Terra also has the larger context window at 1.05M.

## Model Snapshot

| Property | Claude Fable 5.2 | GPT-5.6 Terra |
|----------|----------|----------|
| Creator | Anthropic | OpenAI |
| Type | Proprietary | Proprietary |
| Reasoning | Reasoning | Reasoning |
| Context | 1M | 1.05M |
| Overall Score | 91.19 | 69.42 |
| Benchmarks Covered | 30 | 38 |
| Pricing (input/output) | $8.00 / $40.00 | $2.00 / $12.00 |

## Category Breakdown

### Agentic

- Winner: Directional only
- Claude Fable 5.2 public-lane score: 90.7 (Estimated · #1/132)
- GPT-5.6 Terra public-lane score: 60.4 (Supported · #26/132)

| Benchmark | Claude Fable 5.2 | GPT-5.6 Terra | Winner |
|-----------|-----------|-----------|--------|
| Terminal-Bench 4.0 | 67.60% | Coming soon | Coming soon |
| 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 | 21.50% | Coming soon |
| Terminal-Bench 3.0 | Coming soon | 20.8% | Coming soon |
| Terminal-Bench 2.1 | Coming soon | 87.4% | Coming soon |
| BrowseComp | Coming soon | 87.5% | Coming soon |
| OSWorld 2.0 | Coming soon | 50.2% | Coming soon |
| CyberGym | Coming soon | 81.8% | Coming soon |
| ExploitGym | Coming soon | 23.2% | Coming soon |
| Toolathlon | Coming soon | 53.1% | Coming soon |
| Terminal-Bench 2.1 (Vals) | Coming soon | 77.5% | Coming soon |
| ApprenticeBench | Coming soon | 16% | Coming soon |
| MazeBench | Coming soon | 6% | Coming soon |

### Coding

- Winner: Directional only
- Claude Fable 5.2 public-lane score: 86.9 (Estimated · #1/158)
- GPT-5.6 Terra public-lane score: 61.8 (Supported · #18/158)

| Benchmark | Claude Fable 5.2 | GPT-5.6 Terra | Winner |
|-----------|-----------|-----------|--------|
| SWE-bench Pro | 93% | 63.4% | Claude Fable 5.2 |
| SWE Multilingual | 96.6% | Coming soon | Coming soon |
| SWE Multimodal | 74.1% | Coming soon | Coming soon |
| DeepSWE | 74.3% | 69.6% | Claude Fable 5.2 |
| FrontierSWE v2 | 69.9% | Coming soon | Coming soon |
| ProgramBench | 85.6% | Coming soon | Coming soon |
| FrontierCode 2.0 | 49.1% | Coming soon | Coming soon |
| CursorBench 4.0 | 60.0% | 41.3% | Claude Fable 5.2 |
| Terminal-Bench 2.1 | Coming soon | 87.4% | Coming soon |
| FrontierCode 1.1 Extended | Coming soon | 55.8% | Coming soon |
| CursorBench 3.2 | Coming soon | 64.9% | Coming soon |
| VulcanBench v3 | Coming soon | 87.0% | Coming soon |
| LiveCodeBench (Vals) | Coming soon | 85.9% | Coming soon |
| SWE-bench (Vals) | Coming soon | 95.4% | Coming soon |

### Reasoning

- Winner: Claude Fable 5.2
- Claude Fable 5.2 public-lane score: 90.7 (Supported · #1/157)
- GPT-5.6 Terra public-lane score: 69.1 (Supported · #18/157)

| Benchmark | Claude Fable 5.2 | GPT-5.6 Terra | Winner |
|-----------|-----------|-----------|--------|
| ARC-AGI-3 | 65.7% | 0.8% | Claude Fable 5.2 |
| ARC-AGI-3 Provider Adapter | 94.90% | Coming soon | Coming soon |
| STEM Professor Bench | 61.8% | Coming soon | Coming soon |
| ARC-AGI-2 | Coming soon | 83.9% | Coming soon |
| ARC-AGI-1 | Coming soon | 96.50% | Coming soon |

### Multimodal & Grounded

- Winner: Directional only
- Claude Fable 5.2 public-lane score: 89.8 (Estimated · #1/67)
- GPT-5.6 Terra public-lane score: 68.9 (Supported · #15/67)

| Benchmark | Claude Fable 5.2 | GPT-5.6 Terra | 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 | 92.26% | Coming soon |
| ParseBench | Coming soon | 67.06% | Coming soon |
| MMMU-Pro | Coming soon | 80.7% | Coming soon |
| MMMU-Pro w/ Python | Coming soon | 82% | Coming soon |

### Knowledge

- Winner: Claude Fable 5.2
- Claude Fable 5.2 public-lane score: 97.6 (Supported · #1/179)
- GPT-5.6 Terra public-lane score: 68.2 (Supported · #20/179)

| Benchmark | Claude Fable 5.2 | GPT-5.6 Terra | 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 |
| GPQA | Coming soon | 92.9% | Coming soon |
| GPQA-D | Coming soon | 92.9% | Coming soon |
| HLE-Verified | Coming soon | 51.1% | Coming soon |
| LABBench2 | Coming soon | 81.2% | Coming soon |
| HealthBench Professional | Coming soon | 57.7% | Coming soon |
| HealthBench Hard | Coming soon | 32.7% | Coming soon |
| GPQA Diamond (Vals) | Coming soon | 90.9% | Coming soon |
| MMLU-Pro (Vals) | Coming soon | 86.7% | Coming soon |

### Multilingual

- Winner: Not comparable
- Claude Fable 5.2 public-lane score: Coming soon
- GPT-5.6 Terra public-lane score: Coming soon

| Benchmark | Claude Fable 5.2 | GPT-5.6 Terra | 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
- GPT-5.6 Terra public-lane score: 87.1 (#42/157)

### Mathematics

- Winner: Not comparable
- Claude Fable 5.2 public-lane score: Coming soon
- GPT-5.6 Terra public-lane score: 86.6 (Unranked · 3 rankable rows)

| Benchmark | Claude Fable 5.2 | GPT-5.6 Terra | Winner |
|-----------|-----------|-----------|--------|
| FrontierMath (legacy) | Coming soon | 84.9% | Coming soon |
| FrontierMath v2 (Tiers 1-3) | Coming soon | 84.900% | Coming soon |
| FrontierMath v2 (Tier 4) | Coming soon | 68.300% | Coming soon |

## FAQ

### Which is better overall, Claude Fable 5.2 or GPT-5.6 Terra?

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 GPT-5.6 Terra?

The widest category gap is in agentic, where the averages are 90.7 for Claude Fable 5.2 and 60.4 for GPT-5.6 Terra.

### 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 GPT-5.6 Terra cover on BenchLM?

GPT-5.6 Terra currently has 38 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)
- [GPT-5.6 Terra vs Claude Fable 5.1](/compare/claude-fable-5-1-vs-gpt-5-6-terra)
- [Claude Fable 5.2 vs Claude Fable 5](/compare/claude-fable-vs-claude-fable-5-2)
- [GPT-5.6 Terra vs Claude Fable 5](/compare/claude-fable-vs-gpt-5-6-terra)

## Explore More

- [Claude Fable 5.2 profile](/models/claude-fable-5-2)
- [GPT-5.6 Terra profile](/models/gpt-5-6-terra)
- [Compare Pricing](/llm-pricing)
- [Alternative Finder](/tools/alternative-finder)
- [LLM Selector](/tools/llm-selector)
- [Overall Rankings](/best/overall)