Opus 5 vs. Fable 5: What does half the price buy?

The New Stack · 2 months ago · 43 ● 5 sources

Anthropic released Claude Opus 5 at half the price of Claude Fable 5 ($5/$25 per million tokens versus $10/$50), claiming comparable performance despite stating Fable 5 remains more capable overall. The author tested both models on three reasoning-heavy tasks—bug diagnosis, financial analysis, and conflicting claims evaluation—spending $6.67 on Opus 5 and $11.76 on Fable 5 for similar token output. Opus 5 excels at catching individual details and facts (26 of 27 errors found) while Fable 5 performs better at higher-level reasoning and synthesis, making model choice dependent on whether the task requires detail accuracy or conceptual understanding.