GPT-5.1 is the latest frontier-grade model in the GPT-5 series, offering stronger general-purpose reasoning, improved instruction adherence, and a more natural conversational style compared to GPT-5. It uses adaptive reasoning to allocate c…
Model details →OpenAI: GPT-5.1 vs OpenAI: GPT-5.1-Codex-Max
OpenAI: GPT-5.1 and OpenAI: GPT-5.1-Codex-Max are evenly matched on 6 axes — pick the one whose provider, latency, or licensing fits your stack.
GPT-5.1-Codex-Max is OpenAI’s latest agentic coding model, designed for long-running, high-context software development tasks. It is based on an updated version of the 5.1 reasoning stack and trained on agentic workflows spanning software e…
Model details →Side-by-side comparison
| Capability | OpenAI: GPT-5.1 | OpenAI: GPT-5.1-Codex-Max | Winner |
|---|---|---|---|
| Context window Maximum number of input tokens the model can attend to in a single request. | 400K | 400K | Tie |
| Input price (per 1M) Cost per million input tokens billed by the provider. | $1.25 | $1.25 | Tie |
| Output price (per 1M) Cost per million output tokens billed by the provider. | $10.00 | $10.00 | Tie |
| Tool / function calling First-class support for emitting structured tool calls. | Yes | Yes | Tie |
| Vision input Accepts image inputs alongside text. | Yes | Yes | Tie |
| Reasoning mode Internal chain-of-thought / extended-thinking support. | Yes | Yes | Tie |
Frequently asked questions
Is OpenAI: GPT-5.1 better than OpenAI: GPT-5.1-Codex-Max?
OpenAI: GPT-5.1 and OpenAI: GPT-5.1-Codex-Max are evenly matched on 6 axes — pick the one whose provider, latency, or licensing fits your stack.
What's the price difference between OpenAI: GPT-5.1 and OpenAI: GPT-5.1-Codex-Max?
Input: $1.25 vs $1.25 per 1M tokens. Output: $10.00 vs $10.00 per 1M tokens.
What context windows do OpenAI: GPT-5.1 and OpenAI: GPT-5.1-Codex-Max support?
OpenAI: GPT-5.1 supports up to 400K tokens. OpenAI: GPT-5.1-Codex-Max supports up to 400K tokens.
Do both OpenAI: GPT-5.1 and OpenAI: GPT-5.1-Codex-Max support tool calling?
OpenAI: GPT-5.1: yes. OpenAI: GPT-5.1-Codex-Max: yes.