Claude Fable 5 vs GPT-6 Luna
Claude Fable 5 (Anthropic) and GPT-6 Luna (OpenAI) compared on benchmarks, pricing, context window, and use-case rankings.
- GPT-6 Luna is cheaper on input tokens — $0.10 vs $10.00 per 1M.
- GPT-6 Luna has a larger context window (1.1M vs 1M tokens).
- Claude Fable 5 ranks higher for coding (96th vs 81th percentile).
| Attribute | Claude Fable 5 | GPT-6 Luna |
|---|---|---|
| Scores | ||
| Intelligence (ECI) | 163 | — |
| Coding | 96 | 81 |
| Math | 96 | — |
| Reasoning & Knowledge | 89 | 69 |
| Agentic & Tools | 94 | — |
| Specifications | ||
| Developer | Anthropic | OpenAI |
| Family | Claude | GPT |
| Released | Jun 9, 2026 | Sep 22, 2026 |
| Parameters | — | — |
| Availability | API access | — |
| Context window | 1M | 1.1M |
| Price — $/M input | $10.00 | $0.10 |
| Price — $/M output | $50.00 | $0.50 |
| Inputs | text, image, file | file, image, text |
| Outputs | text | text |
| Benchmarks | ||
| AIME 2024/2025 | 100% | — |
| APEX | 64% | — |
| ARC-AGI | 99% | — |
| ARC-AGI-2 | 89% | — |
| GPQA Diamond | 86% | — |
| Humanity's Last Exam | 56% | 39% |
| SciCode | 61% | 55% |
| SimpleBench | 82% | — |
| SimpleQA Verified | 71% | — |
| WebDev Arena | 1628 | — |
| WeirdML | 92% | — |
| τ²-bench | 99% | — |
Use-case scores are 0–100 percentile composites across each area’s benchmarks, ranked against every model from the past year. Highlighted cells lead each row. Open a model for the full picture.
Frequently asked questions
Which is cheaper, Claude Fable 5 or GPT-6 Luna?
GPT-6 Luna is cheaper on input tokens at $0.10 per million, versus $10.00 (representative OpenRouter pricing).
Which has a larger context window, Claude Fable 5 or GPT-6 Luna?
GPT-6 Luna supports up to 1.1M tokens, compared with 1M for the other.
Which is better for coding, Claude Fable 5 or GPT-6 Luna?
Across coding benchmarks like SWE-bench Verified and Terminal-Bench, Claude Fable 5 ranks higher — 96th vs 81th percentile among the models tracked on Model Beat.
Want a different match-up? Open the compare tool to add or swap models.
More comparisons
Benchmarks & model data from Epoch AI (CC BY); pricing & specs from OpenRouter. ECI = Epoch Capabilities Index.