Claude Fable 5 vs Claude Opus 4.8
Head to head on 40 shared benchmarks, with price, context window, and release dates.
Benchmark scores
42evals · sort by any column, ⤢ to expand fullscreen
| Model | |||||||||||||||||||||||||||||||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Claude Fable 5 Anthropic | 17.4% | 83.9% | 38.6% | 71.8% | 90.0% | 1340elo | 1933elo | 83 | 78.0% | 56.3% | 29.3% | 29.8% | 1932elo | 92.6% | 66.0% | 55.5% | 63.5% | 13.3% | 81.4% | 78.6% | 80.0% | 59.9% | 88.5% | 93.9% | 87.3% | 56.1% | 88.5% | 68.9% | 85.0% | 95.0% | 51.9% | 60.2% | 80.3% | 76.9% | 88.0% | 62.9% | 66.0% | 74.2% | 90.4% | 98.5% | - | - | 69.4% |
| Claude Opus 4.8 Anthropic | 15.5% | 80.4% | 14.5% | 66.7% | 67.0% | 1281elo | 1835elo | 80.8 | 40.0% | 53.9% | 13.4% | 22.5% | 1890elo | 92.0% | 56.9% | 48.7% | 62.2% | 10.4% | 80.1% | 79.3% | 78.3% | 67.4% | 81.4% | 84.3% | 89.7% | 53.2% | 85.8% | 69.9% | 83.4% | 69.0% | 54.8% | 53.5% | 69.2% | 75.6% | 82.7% | 58.3% | 60.9% | 70.9% | 82.7% | 94.4% | 47.2% | 91.8% | 63.4% |
2 / 2 models
| Attribute | Claude Fable 5 Anthropic | Claude Opus 4.8 Anthropic |
|---|---|---|
| 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. | Claude Opus 4.8 (Adaptive Reasoning, Max Effort) is an AI model from Anthropic. |
| Family | Claude | Claude |
| Params | - | - |
| Open weights | closed | - |
| License | - | - |
| Released | 9 Jun 2026 | 28 May 2026 |
| Context | 1,000,000 | 1,000,000 |
| Input $/1M | $10.00 | $5.00 |
| Output $/1M | $50.00 | $25.00 |
| Cache read $/1M | $1.000 | $0.500 |
| Cache write $/1M | $12.500 | $6.250 |
| Speed | 66 tok/s | 0 tok/s |
| Latency | 49.62 s | 0.00 s |
| Modalities | text, image, file | text, image, file |
| Providers | - | - |
| Publisher | Anthropic | Anthropic |
| Reported scores | Finance Agent (v2)56.3% IFBench63.5% (AA) Swebenchpro80.3% LiveBench - Math93.9% (LiveBench) LiveBench - Coding78.6% (LiveBench) |
FAQ
- Is Claude Fable 5 or Claude Opus 4.8 better?
- Across the 40 benchmarks both models report on Sophon, Claude Fable 5 leads on 35 of them. Which one is "better" depends on the benchmark - the table above shows every shared score.
- How do Claude Fable 5 and Claude Opus 4.8 compare on GPQA Diamond?
- Claude Fable 5 scores 92.6% and Claude Opus 4.8 scores 92.0% on GPQA Diamond.
- Which is cheaper, Claude Fable 5 or Claude Opus 4.8?
- Claude Opus 4.8 is cheaper at $25.00 per million output tokens against $50.00 for Claude Fable 5 - about 2.0x.
- When were Claude Fable 5 and Claude Opus 4.8 released?
- Claude Fable 5 was released 9 Jun 2026 by Anthropic. Claude Opus 4.8 was released 28 May 2026 by Anthropic.
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