GPT-5.1-Codex-Max API Pricing
OpenAI · Mid-tier · Proprietary · released 2025-12. Prices in USD per 1 million tokens. Data snapshot: 2026-09-28.
GPT-5.1-Codex-Max has held the same list price since 2026-08-15 and is the 85th cheapest of 108 Mid-tier models. Only one host, Azure, sells it, so there is no second price to shop. No Arena score is published for it, so it carries no Efficiency score and cannot hold the FinOps Friendly badge.
- Input: $1.25 per 1M tokens
- Output: $10.00 per 1M tokens
- Batch API (input/output): not published
- Prompt-cache read: $0.13
- Context window: 400K
GPT-5.1-Codex-Max market position
On blended price ($7.38 per 1M tokens at 30% input, 70% output) it is cheaper than 17% of Mid-tier models: 85th cheapest of 108, tied with 5 others. Across every category it is cheaper than 18% of priced text models in the catalogue: 227th cheapest of 281, tied with 5 others.
GPT-5.1-Codex-Max licence, size and capabilities
GPT-5.1-Codex-Max is recorded here as proprietary: access is through an API, priced by the token. Its parameter count is not published. Listed capabilities: Text, Vision, Reasoning, Code, Agents. Filling its 400K context window once costs $0.50 in input tokens at list price.
Monthly cost at 100K requests, by business use case
From the after-discounts figure (prompt caching on the cached input share, batch API for async workloads, only where the provider publishes those rates), which assumes you implement both, to the list price. One figure means no discount is published.
| Use case | Tokens (in/out) | Monthly (after discounts – list) |
|---|---|---|
| Support Ticket | 1,500 / 500 | $586 – $688 |
| Knowledge Q&A | 2,000 / 800 | $893 – $1.1K |
| Meeting Summary | 10,000 / 1,200 | $2.3K – $2.5K |
| Marketing Content | 2,500 / 1,800 | $2.1K |
| Coding Task | 3,000 / 2,000 | $2.2K – $2.4K |
| Invoice Processing | 1,500 / 600 | $737 – $788 |
| Call Summary | 2,000 / 700 | $928 – $950 |
| Agent Workflow | 6,000 / 3,000 | $3.3K – $3.8K |
GPT-5.1-Codex-Max pricing by host
A host is a company that runs the model and sells it by the token — the lab that made it, a cloud platform like Amazon Bedrock, Azure or Vertex, or an independent provider. One model, several sellers, and often several prices. This model is sold by 1 host. The price quoted above is the one we publish so that models stay comparable; it is not necessarily the cheapest way to buy this model. List prices as published on 2026-09-28 via OpenRouter — negotiated rates, committed-use discounts and provisioned capacity are not shown.
Azure is the only host with a published rate, $1.25 input / $10.00 output per 1M tokens, which is the price shown on this page.
| Host | Input $/1M | Output $/1M |
|---|---|---|
| Azure (the price shown above) | $1.25 | $10.00 |
GPT-5.1-Codex-Max price history
GPT-5.1-Codex-Max has been in our daily price archive since tracking began on 2026-08-15, when it listed at $1.25 input / $10.00 output per 1M tokens. No list price change since tracking began on 2026-08-15. Last checked against the 2026-09-28 snapshot.
Alternatives to GPT-5.1-Codex-Max
- Next cheaper Mid-tier model: GLM 5.3 Prime (Zhipu) at $7.00 blended, 5% less.
- Next more expensive: MiMo-V2.6-Pro-UltraSpeed (Xiaomi) at $7.39 blended, under 1% more.
Common questions about GPT-5.1-Codex-Max pricing
- How much does GPT-5.1-Codex-Max cost?
- GPT-5.1-Codex-Max costs $1.25 per million input tokens and $10.00 per million output tokens on the API.
- Does GPT-5.1-Codex-Max offer batch or cached pricing?
- Prompt-cache reads cost $0.13/M input tokens. No batch pricing is published.
- What would GPT-5.1-Codex-Max cost per month?
- For a support-ticket workload (1,500 input + 500 output tokens per request) at 100K requests/month, GPT-5.1-Codex-Max costs about $688 at list prices.
- Has the price of GPT-5.1-Codex-Max changed?
- GPT-5.1-Codex-Max has been in our daily price archive since tracking began on 2026-08-15, when it listed at $1.25 input / $10.00 output per 1M tokens. No list price change since tracking began on 2026-08-15. Last checked against the 2026-09-28 snapshot.
These are list prices: real cost also depends on caching, batching, negotiated discounts, marketplace agreements, and existing contracts. Get a FinOps review from OptimNow or compare all models.
Build the business case for GPT-5.1-Codex-Max in the AI ROI Calculator: add your business value on top of these costs to get ROI, break-even and payback.
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