gpt-5.1-codex — API, Pricing & Context Window | Vivgrid
gpt-5.1-codex — API, Pricing & Context Window
gpt-5.1-codex on Vivgrid: a Codex-tuned coding model on the Responses API with a 400K context window and three-region geo-distributed acceleration.
gpt-5.1-codex is OpenAI's Codex-tuned 5.1 coding model, designed for agentic software engineering through the Responses API. It is a well-rounded, cost-effective option for everyday coding agents.
Vivgrid accelerates gpt-5.1-codex across AMER, EMEA, and APAC — the broadest reach in the Codex line — with a 400K-token context window for project-scale sessions.
Specifications
| Provider | OpenAI |
| Model ID | gpt-5.1-codex |
| Best for | Coding |
| Context window | 400,000 tokens |
| Max output | 128,000 tokens |
| Modalities | Text, Image, Audio |
| Tool / function calling | Yes |
| Knowledge cutoff | 2024-09 |
| Acceleration | ⚡ Geo-Distributed — AMER, EMEA, APAC |
Pricing
Pricing in USD per 1M tokens, matching the provider's rates.
| Input | Cached input | Output |
|---|---|---|
| $1.25 | $0.125 | $10.00 |
Quick start
Call gpt-5.1-codex through Vivgrid's unified, OpenAI-compatible endpoint. Get an API key from the Vivgrid Console.
curl https://api.vivgrid.com/v1/responses \
-H "Authorization: Bearer $VIVGRID_API_KEY" \
-H "Content-Type: application/json" \
-d '{\n "model": "gpt-5.1-codex",\n "input": "Refactor this function and explain the change.",\n "stream": true\n }'
Ideal use cases
- Day-to-day coding agents on the Responses API
- Globally distributed teams needing low latency in three regions
- Automated edits, reviews, and test generation
- Tool-calling workflows that chain editor and shell actions
Related models
- gpt-5.1-codex-max — extended-effort variant
- gpt-5.2-codex — the next Codex generation
- gpt-5.1 — general-purpose 5.1 model