The Orchestrator › Models › OpenAI

OpenAI: GPT-5.1-Codex

GPT-5.1-Codex is a specialized version of GPT-5.1 optimized for software engineering and coding workflows. It is designed for both interactive development sessions and long, independent execution of complex engineering tasks....

Specifications

ProviderOpenAI
Model IDopenai/gpt-5.1-codex
Context window400K tokens (400,000)
Modalitiestext + image → text
TokenizerGPT
Router sourcesOpenRouter, Vercel AI Gateway
Released2025-11-13
Tracked since2026-11-14
PopularityNot in the ranked set
ReasoningMandatory

Pricing (per million tokens)

VariantSourceAPI IDInputOutputContext
standardOpenRouteropenai/gpt-5.1-codex$1.25$10.00400K
standardVercel AI Gatewayopenai/gpt-5.1-codex$1.25$10.00400K

Recorded price history

DateInput / 1MOutput / 1MContext
2026-11-14$1.25$10.00400K
2026-11-14$1.25$10.00400K

Capabilities

Vision (image input)Agentic tool useStructured outputsReasoning (always on)256K+ context windowControllable reasoningZero data retentionNo training on inputs (attested)

Trust flags come from TrustedRouter's per-provider attestations.

Supported parameters

include_reasoning, max_completion_tokens, reasoning, reasoning_effort, response_format, seed, structured_outputs, tool_choice, tools, verbosity