GPT-5.5 vs Gemini 3.5 Flash

OpenAI GPT-5.5Google Gemini 3.5 Flash
VendorOpenAIGoogle
Context window1,050,0001,048,576
Max output128,00065,536
ReasoningYesYes
Tool callingYesYes
File inputYesYes
Inputtext, imagetext, image, video, audio, file
Outputtexttext
Released2026-04-232026-05-19