xAI's Grok models, including Grok 4.20 and Grok 4.1 Fast, are available through API with pricing ranging from $0.20 input / $0.50 output per 1M tokens for Grok 4.1 Fast to $2.00 input / $6.00 output per 1M tokens for Grok 4.20, and also integrated into X Premium+ subscriptions.