GPT-5.1-Codex-Max API Cost Calculator
Estimate your monthly API costs for GPT-5.1-Codex-Max from Openai.
Pricing per 1M tokens
Pricing last verified: Mar 21, 2026
30-Day Price History
Solid line: input price · Dashed line: output price
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Cost Breakdown
Compare with Similar Models
| Model | Input/1M | Output/1M |
|---|---|---|
| GPT-5 Openai | $1.25 | $10.00 |
| GPT-5 Chat Openai | $1.25 | $10.00 |
| GPT-5 Codex Openai | $1.25 | $10.00 |
| GPT-5.1 Openai | $1.25 | $10.00 |
| GPT-5.1 Chat Openai | $1.25 | $10.00 |
Frequently Asked Questions
How much does GPT-5.1-Codex-Max cost per token?
GPT-5.1-Codex-Max is priced at $1.25 per 1M input tokens and $10.00 per 1M output tokens. Use the calculator above to estimate your monthly costs based on your usage volume.
What is the context window for GPT-5.1-Codex-Max?
GPT-5.1-Codex-Max has a context window of 400K tokens (400,000 tokens). The maximum output length is 128K tokens.
Does GPT-5.1-Codex-Max support image inputs (vision)?
Yes, GPT-5.1-Codex-Max supports vision/image inputs. You can send images as part of your prompts.
Does GPT-5.1-Codex-Max support function calling (tool use)?
Yes, GPT-5.1-Codex-Max supports function calling (also called tool use). You can define custom functions that the model can invoke as part of its responses.
How does GPT-5.1-Codex-Max compare to similar models?
GPT-5.1-Codex-Max costs $1.25 input and $10.00 output per 1M tokens. GPT-5.1-Codex-Max is competitively priced compared to GPT-5.1 Chat ($1.25 input / $10.00 output per 1M tokens). See the "Compare with Similar Models" table above, or visit the GPT-5.1 Chat page at /tools/cost-calculator/openai/gpt-5-1-chat.