gpt-4o-image vs grok-4-fast-non-reasoning

OpenAI gpt-4o-imagexAI grok-4-fast-non-reasoning
VendorOpenAIxAI
Context window—2,097,152
Max output—30,000
ReasoningNoNo
Tool callingNoYes
File inputNoYes
Inputtexttext, image
Outputimage, texttext
Released—2025-08-27