OpenAI: GPT-5.1-Codex-Mini
Analysis Summary
OpenAI's GPT-5.1-Codex-Mini is a multimodal coding model with a 400K context window, vision, tool use, and function calling. Its measured mathematics, coding, instruction-following, long-context, and agentic results show a strong technical profile, while its lower pricing supports more frequent engineering use than the full Codex model.
It fits code generation, test writing, repository analysis, debugging, and structured development agents. The model's general intelligence remains below frontier systems, and its agentic result is less compelling than its coding performance, so autonomous execution should use clear tool permissions and verification. It is also better suited to technical output than nuanced client-facing prose.
Adopt it as a cost-conscious coding and engineering-agent choice. Reserve larger flagship models for ambiguous architecture, difficult reasoning, and high-stakes review.
Assessed September 7, 2026
Editorial notes
GPT-5.1-Codex-Mini delivers strong coding and tool-use results with a 400K context, vision, and lower pricing than the full Codex model. It is a strong volume engineering option, with general reasoning below flagship level.
Rankings consider pricing, capabilities, benchmarks, and real-world applicability and are refreshed as new models launch. Feedback?
DFO Verdict
GPT-5.1-Codex-Mini delivers strong coding and tool-use results with a 400K context, vision, and lower pricing than the full Codex model. It is a strong volume engineering option, with general reasoning below flagship level.
Benchmark scores
Magenta = intelligence · Ink = technical/agentic · Cyan = content & long-context · Grey = community benchmarks. Data: Artificial Analysis, Hugging Face.
24 Intelligence Index·91.7 Math Index
How OpenAI: GPT-5.1-Codex-Mini compares
OpenAI: GPT-5.1-Codex-Mini ranks #131 of 435 AI models we track for overall intelligence. Its 400K-token context window is larger than 75% of the models we list. At $0.25 per million input tokens it is cheaper than 52% of comparable models.
Dark bar = input · light bar = output, scaled to the priciest peer.
1M tokens ≈ 8 full-length novels or ~2,500 pages of business documents in a single request.
Strongest on business fit. The pulled-in technical corner is the trade-off, and if the shape matters more than the price, this is your model.
Compare shapes side-by-side →Pricing
| Token Type | Cost per 1M tokens | Cost per 1K tokens |
|---|---|---|
| Input | $0.25 | $0.000250 |
| Output | $2.00 | $0.002000 |
What would OpenAI: GPT-5.1-Codex-Mini cost your business?
Pick the job that looks most like yours, then fine-tune with the sliders. Estimates update live.
A website chatbot handling around 100 customer conversations a day, a few short messages each.
Full calculator with 756 models → Price Calculator
These numbers get smaller with the right architecture.
We route routine calls to cheap models and save OpenAI: GPT-5.1-Codex-Mini for the hard ones. Most clients cut their estimate by 60-80%.
Talk to our teamAbout OpenAI: GPT-5.1-Codex-Mini
GPT-5.1-Codex-Mini is a smaller and faster version of GPT-5.1-Codex
Frequently asked questions about OpenAI: GPT-5.1-Codex-Mini
How much does OpenAI: GPT-5.1-Codex-Mini cost?
OpenAI: GPT-5.1-Codex-Mini costs $0.25 per million input tokens and $2.00 per million output tokens.
What is the context window of OpenAI: GPT-5.1-Codex-Mini?
OpenAI: GPT-5.1-Codex-Mini has a context window of 400,000 tokens (400K).
What can OpenAI: GPT-5.1-Codex-Mini do?
OpenAI: GPT-5.1-Codex-Mini supports image/vision input, tool use, and function calling.
Who created OpenAI: GPT-5.1-Codex-Mini?
OpenAI: GPT-5.1-Codex-Mini is developed by OpenAI and was released on November 13, 2025.