OpenAI model
GPT-5.1-Codex-Max API cost calculator
GPT-5.1-Codex-Max costs $1.25 per 1M input tokens and $10 per 1M output tokens on the OpenAI API, with a 400K-token context window. A typical request (2K input, 500 output tokens) costs $0.0075 — about $225/month at 1,000 requests per day. Use the calculator below to model your exact workload.
Find me a cheaper modelWhat real workloads cost on GPT-5.1-Codex-Max
| Workload | Tokens (in / out) | Per request | Per 1K requests |
|---|---|---|---|
| Chatbot message | 500 / 300 | $0.0036 | $3.63 |
| RAG query with context | 4,000 / 500 | $0.01 | $10.00 |
| Document summarization | 20,000 / 1,000 | $0.04 | $35.00 |
| Agent coding session | 100,000 / 5,000 | $0.17 | $175 |
GPT-5.1-Codex-Max vs other OpenAI models
| Model | Input /1M | Output /1M | Context |
|---|---|---|---|
| GPT-5.1-Codex-Max | $1.25 | $10 | 400K |
| GPT-5.6 Luna Pro | $0.20 | $1.20 | 1.1M |
| GPT-5.6 Luna | $0.20 | $1.20 | 1.1M |
| GPT-5.6 Terra Pro | $2 | $12 | 1.1M |
| GPT-5.6 Terra | $2 | $12 | 1.1M |
Frequently asked questions
How much does GPT-5.1-Codex-Max cost per 1M tokens?
According to current pricing data, GPT-5.1-Codex-Max costs $1.25 per 1M input tokens and $10 per 1M output tokens. Processing 1M tokens each way costs $11.25.
What does a typical API request to GPT-5.1-Codex-Max cost?
A typical request with 2,000 input tokens and 500 output tokens costs $0.0075. At 1,000 requests per day that is $7.50 daily, or about $225 per month.
What is GPT-5.1-Codex-Max's context window?
GPT-5.1-Codex-Max supports a 400K-token context window (400,000 tokens).
Does GPT-5.1-Codex-Max support prompt caching?
Yes. Cached input tokens cost $0.13 per 1M — a 90% discount versus the standard input rate, which matters for agents and chat apps that resend the same system prompt.
What is a cheaper alternative to GPT-5.1-Codex-Max?
Ling-2.6-flash from Inclusionai is currently the cheapest comparable option at $0.01 per 1M input tokens versus $1.25 for GPT-5.1-Codex-Max — roughly 125x cheaper on input.
Prices may differ from OpenAI's official pricing page for batch, tiered, or fine-tuned usage. Compare all current prices on the live model pricing dashboard, see GPT-5.1-Codex-Max vs Ling-2.6-flash pricing, or run GPT-5.1-Codex-Max head-to-head against other models in the side-by-side comparison playground.
Pricing data via the OpenRouter models API.