GPT-5.1 vs Claude Sonnet 4.6

OpenAI GPT-5.1Anthropic Claude Claude Sonnet 4.6
VendorOpenAIAnthropic Claude
Context window400,0001,000,000
Max output128,000128,000
ReasoningYesYes
Tool callingYesYes
File inputYesYes
Inputtext, imagetext, image
Outputtexttext
Released2025-11-122026-02-16