gpt-5-nano vs Doubao-Seedream-4.5

OpenAI gpt-5-nanoByteDance Doubao-Seedream-4.5
VendorOpenAIByteDance
Context window400,000
Max output128,000
ReasoningYesNo
Tool callingYesNo
File inputYesYes
Inputtext, imagetext, image
Outputtextimage
Released2025-08-072025-12-02