Claude Fable 5.1 vs GPT-Image-2.5 (Sunburst)

A direct, empirical evaluation of Claude Fable 5.1 (Anthropic) against GPT-Image-2.5 (Sunburst) (OpenAI).

Claude Fable 5.1

Developed by Anthropic · Proprietary Frontier parameters

Full-repository software refactoring, agentic tool workflows, formal verification, and 1.5M-token needle retrieval.

GPT-Image-2.5 (Sunburst)

Developed by OpenAI · Proprietary Multimodal DiT parameters

High-fidelity typographic rendering, raytracing reflection accuracy, sketch-to-image conditioning, and localized comment inpainting.