Claude Fable 5 vs gpt-oss-120b
Head to head on 18 shared benchmarks, with price, context window, and release dates.
Benchmark scores
53evals · sort by any column, ⤢ to expand fullscreen
| Model | ||||||||||||||||||||||||||||||||||||||||||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Claude Fable 5 Anthropic | 71.8% | 90.0% | 1933elo | 83 | 92.6% | 55.5% | 63.5% | 81.4% | 78.6% | 80.0% | 59.9% | 88.5% | 93.9% | 87.3% | 60.2% | 76.9% | 62.9% | 98.5% | - | - | 17.4% | - | - | 83.9% | 38.6% | 1340elo | 78.0% | 56.3% | 29.3% | 29.8% | 1932elo | - | 66.0% | 13.3% | - | - | - | 56.1% | 88.5% | - | - | 68.9% | 85.0% | 95.0% | 51.9% | - | - | 80.3% | 88.0% | - | 66.0% | 74.2% | 90.4% | 69.4% |
| gpt-oss-120b OpenAI | 58.2% | 13.0% | 959elo | 35.8 | 67.2% | 5.9% | 58.3% | 51.0% | 60.2% | 38.8% | 50.3% | 48.6% | 68.9% | 39.2% | 36.0% | 71.6% | 5.3% | 45.0% | 41.8% | 66.7% | - | 38.9% | 7.6% | - | - | - | - | - | - | - | - | 57.6 | - | - | 70.7% | 1.62 | 1.53 | - | - | 80.0% | 77.5% | - | - | - | - | 97.9% | 26.0% | - | - | 65.6% | - | - | - | 49.6% |
2 / 2 models
| Attribute | Claude Fable 5 Anthropic | gpt-oss-120b OpenAI |
|---|---|---|
| Description | Claude Fable 5 is Anthropic's most capable widely released model, built for the most demanding reasoning and long-horizon agentic work. Shares its base model with the invitation-only Claude Mythos 5. | GPT-Oss 120b is an AI model from OpenAI, released with open weights. |
| Family | Claude | GPT |
| Params | - | - |
| Open weights | closed | open |
| License | - | apache-2.0 |
| Released | 9 Jun 2026 | 5 Aug 2025 |
| Context | 1,000,000 | 131,072 |
| Input $/1M | $10.00 | $0.15 |
| Output $/1M | $50.00 | $0.60 |
| Cache read $/1M | $1.000 | $0.030 |
| Cache write $/1M | $12.500 | - |
| Speed | 66 tok/s | 186 tok/s |
| Latency | 49.62 s | 0.50 s |
| Modalities | text, image, file | text |
| Providers | - | - |
| Publisher | Anthropic | OpenAI |
| Reported scores | Finance Agent (v2)56.3% IFBench63.5% (AA) Swebenchpro80.3% LiveBench - Math93.9% (LiveBench) LiveBench - Coding78.6% (LiveBench) | GPQA Diamond67.2% (AA) Humanity's Last Exam (HLE)5.9% (AA) LiveCodeBench70.7% (AA) MMLU-Pro77.5% (AA) SciCode36.0% (AA) |
FAQ
- Is Claude Fable 5 or gpt-oss-120b better?
- Across the 18 benchmarks both models report on Sophon, Claude Fable 5 leads on 18 of them. Which one is "better" depends on the benchmark - the table above shows every shared score.
- How do Claude Fable 5 and gpt-oss-120b compare on GPQA Diamond?
- Claude Fable 5 scores 92.6% and gpt-oss-120b scores 67.2% on GPQA Diamond.
- Which is cheaper, Claude Fable 5 or gpt-oss-120b?
- gpt-oss-120b is cheaper at $0.60 per million output tokens against $50.00 for Claude Fable 5 - about 83.3x.
- When were Claude Fable 5 and gpt-oss-120b released?
- Claude Fable 5 was released 9 Jun 2026 by Anthropic. gpt-oss-120b was released 5 Aug 2025 by OpenAI.
Comparing something else? Build your own side-by-side.