Claude Sonnet 4.6 vs GPT-5.1

Anthropic Claude Sonnet 4.6OpenAI GPT-5.1
VendorAnthropicOpenAI
Context window1,000,000400,000
Max output128,000128,000
ReasoningYesYes
Tool callingYesYes
File inputYesYes
Inputtext, imagetext, image
Outputtexttext
Released2026-02-162025-11-12