The closest alternative to Grok 4.20 is Qwen3 235B A22B Thinking 2507 — comparable intelligence (29.5 vs 29.7); for a cheaper option, MiniMax M3 runs $0.300/M vs $1.25/M; for more speed, gpt-oss-120b (free) hits 554 t/s; and the best open-weight substitute is MiniMax M3.
Qwen3 235B A22B Thinking 2507 is the closest alternative to Grok 4.20, with an Intelligence Index of 29.5 (Grok 4.20 scores 29.7) at $0.100 per million input tokens.
Yes — MiniMax M3 costs $0.300 per million input tokens versus $1.25 for Grok 4.20, while staying within ~8 points of its Intelligence Index.
MiniMax M3 is the strongest open-weight alternative to Grok 4.20 — downloadable from Hugging Face and self-hostable, scoring 54.7 on intelligence.