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GPT-5.6 Sol Ultra loses to GPT-5.5 on physics at 3x cost
GPT-5.6 Sol Ultra loses to GPT-5.5 on physics at 3x cost
Jul 9, 2026♥ 375⇄ 27232.6k views
Reusable takeaways
- ›GPT-5.6 Sol Ultra used 32.9K tokens ($0.33) vs GPT-5.5 12.4K tokens ($0.11) for same physics prompts.
- ›Sol Ultra's physics quality was worse than GPT-5.5 on truck flip and train derailment tests.
- ›Grok 4.5 failed two of three tests, only succeeded on train derailment.
How to reproduce
Prompt: 'build three self-contained HTML5 canvas scenes with real physics demos: a monster truck backflipping onto a parked car, a stunt car jumping six buses into a brick wall, a train derailing off a broken bridge into the water.' Models: GPT-5.6 Sol Ultra, Opus 4.8, GPT-5.5, Grok 4.5. Compare token usage, cost, and output quality.
✓ ×2claim
GPT-5.6 Sol Ultra produces weaker physics simulations than GPT-5.5 despite higher cost and token usage.