atomic[.]chat, a desktop app that runs LLMs locally, ran a very revealing comparison for Claude Sonnet 5, Claude Opus 4.8, Claude Sonnet 4.6, and GPT 5.5.
Claude Sonnet 5 just matched GPT 5.5 on 3 physics coding demos at 6x lower cost.
Also spent minimum number of tokens.
• Sonnet 5: 15,047 tokens, $0.15 • Opus 4.8: 23,063 tokens, $0.58 • Sonnet 4.6: 25,824 tokens, $0.39 • GPT 5.5: 31,152 tokens, $0.94