GPT Image 2.5 Dev vs Grok 4.5

OpenAI GPT Image 2.5 DevxAI Grok 4.5
VendorOpenAIxAI
Context window—500,000
Max output—2,000,000
ReasoningNoYes
Tool callingNoYes
File inputYesYes
Inputtext, imagetext, image
Outputimagetext
Released2026-09-082026-07-08