OpenAI: GPT-5.1-Codex
The OpenAI GPT-5.1-Codex is designed to process both text and images, with an impressive context length of 400,000 tokens, making it capable of handling complex tasks that require deep understanding and analysis. It supports reasoning and tools integration, enhancing its utility for a wide range of applications. For those seeking a robust model at a moderate cost, GPT-5.1-Codex might be worth considering. With pricing at $1.25 per million input tokens and $10.0 per million output tokens, it offers a balanced approach to budget-conscious users, though its blended benchmark score of 58.0 across one independent benchmark suggests there is still room for improvement in terms of performance validation.
Benchmark results
Independent, published benchmarks. Blended score 58.0 across 1 benchmark, last refreshed 2026-08-13. How scoring works →
| Benchmark | Measures | Score |
|---|---|---|
| AI Index | broad capability composite | 58.7 |
- Model ID
- openai/gpt-5.1-codex
- Vendor
- openai
- Released
- November 2025
- Tokenizer
- GPT
- Input Modalities
- text, image
- Output Modalities
- text
- Max Output
- 128,000 tokens
- Tool Calling
- ✓ supported
- Structured Output
- ✓ supported
- Reasoning Mode
- ✓ supported
- Vision
- ✓ accepts images
- Audio
- no
- Moderated
- no
What it costs in practice
Computed from the current $1.25/M input and $10.00/M output rates. Run your own numbers →
| Job | Tokens | Cost |
|---|---|---|
| Summarize a 50-page report | 30k in / 1.5k out | $0.05 |
| Classify 1,000 customer emails | 500k in / 50k out | $1.12 |
| A month of a busy support chatbot | 5M in / 2M out | $26.25 |
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Quick answers
- How much does OpenAI: GPT-5.1-Codex cost?
- $1.25 per million input tokens and $10.00 per million output tokens.
- What is OpenAI: GPT-5.1-Codex's context window?
- 400,000 tokens, roughly 600 pages of text in a single request.
- Does OpenAI: GPT-5.1-Codex support tool calling?
- It supports tool calling, structured output, a reasoning mode.
- Can OpenAI: GPT-5.1-Codex process images?
- Yes, it accepts image input.