gpt-5.4 vs GPT-5.6 Luna

OpenAI gpt-5.4OpenAI GPT-5.6 Luna
VendorOpenAIOpenAI
Context window1,050,0001,050,000
Max output128,000128,000
ReasoningYesYes
Tool callingYesYes
File inputYesYes
Inputtext, imagetext, image
Outputtexttext
Released2026-03-042026-07-08