Side-by-side comparison of pricing, 12 benchmarks, and generation speed.
| Metric | Claude Fable 5 (Adaptive Reasoning, Max Effort, Opus 4.8 Fallback) | GPT-5.5 (xhigh) |
|---|---|---|
| Input ($/M tokens) | $12.5 | $5 |
| Output ($/M tokens) | $50 | $30 |
Data from Artificial Analysis API — 12 benchmarks
GPT-5.5 (xhigh) is cheaper overall. Its blended price (3:1 input/output ratio) is $11.25/M tokens vs $21.88/M for Claude Fable 5 (Adaptive Reasoning, Max Effort, Opus 4.8 Fallback).
Claude Fable 5 (Adaptive Reasoning, Max Effort, Opus 4.8 Fallback) wins 5 out of 12 benchmarks compared to 2 for GPT-5.5 (xhigh). See the detailed benchmark chart above for per-category results.
Claude Fable 5 (Adaptive Reasoning, Max Effort, Opus 4.8 Fallback) generates tokens faster at 61 tok/s vs 55 tok/s. However, GPT-5.5 (xhigh) has lower time-to-first-token (78.70s vs 90.38s).
Choose based on your priorities: GPT-5.5 (xhigh) for lower cost, Claude Fable 5 (Adaptive Reasoning, Max Effort, Opus 4.8 Fallback) for stronger benchmark performance, and Claude Fable 5 (Adaptive Reasoning, Max Effort, Opus 4.8 Fallback) for faster generation. For latency-sensitive apps, check the TTFT comparison above.