Comparing 2 models
Claude Fable 5.1 vs GPT-6 Astra
Benchmarks through
Verdict
Claude Fable 5.1 places higher on 21 of the 23 tasks where both are ranked. GPT-6 Astra accepts 1.1x more context.
- Choose Claude Fable 5.1 for Competition Math (#1), Tool & Function Calling (#1), Math & Reasoning (#1).
- Choose GPT-6 Astra for Grounded RAG (#2), Image Understanding (#5).
Built from the published task rankings below; ranks come from each task's own weighted benchmarks, so a win on one task says nothing about another.
Measured head to head
Benchmarks both models were run on
| Evaluation | Claude Fable 5.1 | GPT-6 Astra | Source |
|---|---|---|---|
| FrontierMath Tiers 1-3 (Epoch AI) | 90.2% ± 1.8 | 93.7% ± 1.4 | source · 2026-09-01 |
| LiveBench Agentic Coding | 66.1% | 57.3% | source · 2026-10-16 |
| LiveBench Coding | 86.4% | 80.4% | source · 2026-10-16 |
| LiveBench Data Analysis | 80.3% | 83.0% | source · 2026-10-16 |
| LiveBench Instruction Following | 73.0% | 75.6% | source · 2026-10-16 |
| LiveBench Language | 89.5% | 89.4% | source · 2026-10-16 |
| LiveBench Math | 97.0% | 96.8% | source · 2026-10-16 |
| LiveBench Reasoning | 91.7% | 92.7% | source · 2026-10-16 |
| LMArena Agent | 14.1 | 13.7 | source · 2026-10-14 |
| LMArena Agent Bash Recovery | 11.6 | 5.5 | source · 2026-10-08 |
| LMArena Agent Steerability | 14.7 | 14.6 | source · 2026-10-14 |
| LMArena Agent Task Outcome | 15.7 | 12.5 | source · 2026-10-14 |
| LMArena Agent Tool Hallucination | 0.6 | 0.6 | source · 2026-10-14 |
| LMArena Creative Writing | 1508 Elo | 1421 Elo | source · 2026-10-15 |
| LMArena Instruction Following | 1517 Elo | 1455 Elo | source · 2026-10-15 |
| LMArena Long Query | 1523 Elo | 1461 Elo | source · 2026-10-15 |
| LMArena Math | 1528 Elo | 1465 Elo | source · 2026-10-15 |
| LMArena Search Factuality | 1222 Elo | 1240 Elo | source · 2026-10-13 |
| LMArena Text | 1502 Elo | 1477 Elo | source · 2026-10-15 |
| LMArena Text Factuality | 1498 Elo | 1466 Elo | source · 2026-10-15 |
| LMArena Vision | 1286 Elo | 1286 Elo | source · 2026-10-09 |
| LMArena Vision Diagrams | 1326 Elo | 1311 Elo | source · 2026-10-09 |
| LMArena Vision OCR | 1302 Elo | 1302 Elo | source · 2026-10-09 |
| LMArena WebDev | 1743 Elo | 1780 Elo | source · 2026-10-13 |
| LMArena WebDev Image-to-Web | 1720 Elo | 1731 Elo | source · 2026-10-09 |
| OTIS Mock AIME (Epoch AI) | 100% ± 0 | 100% ± 0 | source · 2026-09-01 |
| SimpleQA Verified (Epoch AI) | 70.8% ± 1.4 | 75.6% ± 1.4 | source · 2026-09-01 |
| Terminal-Bench (4.0) | 57.9% | 58.2% | source · 2026-10-16 |
Values are as published by each evaluator, in its own units; rows from different evaluators are not on a common scale.
task evidence
How they place when the question changes
Lower ranks are better. “Best” marks the strongest option in this shortlist for that task.