QUICK VERDICT — JULY 25, 2026
● For 90% of tasks: Claude Opus 5 — matches Fable 5 at half the price
● For production coding (SWE-bench verified): Fable 5 — 80.4% #1, Opus 5 unpublished on this benchmark
● Default on Claude Max: Opus 5 (as of July 24)
● Effort control: Opus 5 (5-level toggle) — Fable 5 has no effort control
● Batch API: Opus 5 $2.50/$12.50/M — Fable 5 $5/$25/M
● One honest caveat: Anthropic reports higher hallucination rate on Opus 5 vs Opus 4.8 on one factual benchmark
| Feature | Claude Opus 5 | Claude Fable 5 |
|---|
| Input price /1M | $5 | $10 |
| Output price /1M | $25 | $50 |
| Batch API /1M | $2.50/$12.50 | $5/$25 |
| SWE-bench Pro | Not published | 80.4% #1 |
| Frontier-Bench v0.1 | 43.3% | Ahead on some tasks |
| Effort control | 5-level toggle | None |
| Context | 1M | 1M |
| Claude Max default | Yes (as of Jul 24) | 50% weekly limits |
The Decision Framework
Use Claude Opus 5 for: Daily AI work, writing, analysis, research, agentic tasks, mixed workloads where the 5-level effort toggle lets you dial cost vs quality per request. The new Claude Max default for a reason — Anthropic built it to be the everyday model. At $5/$25/M with a Batch API at $2.50/$12.50/M, it is the most cost-efficient Anthropic model with frontier-adjacent intelligence.
Use Claude Fable 5 for: Production code changes where SWE-bench Pro 80.4% accuracy is specifically required, and where you can justify 2× the cost. Fable 5 is still the only Anthropic model with a published and independently-verified SWE-bench Pro score. If your engineering team has validated that Fable 5 passes your code review bar and Opus 5 has not yet been tested — stay on Fable 5 until you complete that test.
One caveat on Opus 5: Anthropic's own documentation reports a higher hallucination rate on Opus 5 vs Opus 4.8 on one factual benchmark. For factual retrieval tasks — customer support, knowledge base queries, fact-checking — run your own eval before switching from Opus 4.8 or Fable 5.
Last updated July 25, 2026. Related: Claude Opus 5 full launch review → · Claude Opus 5 vs GPT-5.6 Sol →