NanoGPTGPT 5.1 Codex model ID, context window & pricing
gpt-codex
Quick facts
Model ID openai/gpt-5.1-codex
Source NanoGPT
Context Window 400000
Pricing $1.25 input / $10.00 output per 1M tokens
Capabilities reasoning
Model overview
GPT 5.1 Codex is an AI model from NanoGPT with 400000 token context window and text, image input support.
Published pricing is $1.25 input and $10.00 output per 1M tokens.
- Workloads that use text, image inputs with text outputs.
- Reasoning-heavy prompts where stepwise problem solving matters.
Model ID openai/gpt-5.1-codex
Provider NanoGPT
Family gpt-codex
Status -
Knowledge Cutoff -
Release Date 2025-11-13
Input Modalities text, image
Output Modalities text
Context Window 400000
Input Limit 400000
Output Limit 128000
Tool Calling No
Reasoning Yes
Structured Output No
Temperature Control -
Open Weights No
Input Cost / 1M tokens $1.25
Output Cost / 1M tokens $10.00
Reasoning Cost / 1M tokens -
Cache Read Cost / 1M tokens -
Cache Write Cost / 1M tokens -