The closest alternative to GPT-5.5 is Qwen3.7 Max — comparable intelligence (56.6 vs 56.7); for a cheaper option, GPT-5.4 runs $2.50/M vs $5.00/M; for more speed, MiniMax M2.7 hits 211 t/s; and the best open-weight substitute is MiniMax M3.
Qwen3.7 Max is the closest alternative to GPT-5.5, with an Intelligence Index of 56.6 (GPT-5.5 scores 56.7) at $1.25 per million input tokens.
Yes — GPT-5.4 costs $2.50 per million input tokens versus $5.00 for GPT-5.5, while staying within ~8 points of its Intelligence Index.
MiniMax M3 is the strongest open-weight alternative to GPT-5.5 — downloadable from Hugging Face and self-hostable, scoring 54.7 on intelligence.