openai
OpenAI: GPT-5.1-Codex
openai/gpt-5.1-codex
For $1, you can send approximately:
~12.7messages
How do we get this number?
One message = ~7,000 input tokens + ~7,000 output tokens
Input cost per message7,000 x $1.25/M = $0.008750
Output cost per message7,000 x $10.00/M = $0.070000
Total cost per message$0.078750
Messages for $112.70
Context window
400k
tokens
Max response
128k
tokens
Input price
$1.25
per million tokens
Output price
$10.00
per million tokens
Modalities
Input:textInput:imageOutput:text
Description
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....