Is Grok 4.1 Fast Reasoning or Grok 4.20 Reasoning cheaper?
Grok 4.1 Fast Reasoning is cheaper ($0.029 / 1M tokens input / $0.072 / 1M tokens output) vs Grok 4.20 Reasoning ($0.181 / 1M tokens input / $0.362 / 1M tokens output). Actual cost depends on your input/output token mix — estimate it with the pricing calculator.