Grok 4.5 vs o4-mini

xAI Grok 4.5OpenAI o4-mini
VendorxAIOpenAI
Context window500,000200,000
Max output2,000,000100,000
ReasoningYesYes
Tool callingYesYes
File inputYesYes
Inputtext, imagetext, image
Outputtexttext
Released2026-07-082025-04-16