Basecamp Bench

TLDR Dev · 5 days ago

A benchmark tested five AI models (Anthropic's Fable 5, OpenAI's GPT-5.6 Sol and GPT-5.5, SpaceX's Grok 4.5, and Google's Gemini Pro 3.1) by having them build a frontend and backend for a Basecamp project from scratch. Fable 5 scored highest on both frontend and backend tracks, while Grok 4.5 completed both builds in 37 minutes for $9.30, offering the best speed-to-cost ratio despite visible polish gaps. The results show significant performance variation across models, with frontend work revealing larger gaps than backend work, suggesting that achieving high-quality UI polish remains a differentiator between leading AI models.