OpenAI: Codex Mini

Image input Text input Text output
Author's Description

codex-mini-latest is a fine-tuned version of o4-mini specifically for use in Codex CLI. For direct use in the API, we recommend starting with gpt-4.1.

Key Specifications
Cost
$$$$$
Context
200K
Released
May 16, 2025
Speed
Ability
Reliability
Supported Parameters

This model supports the following parameters:

Reasoning Structured Outputs Response Format Seed Max Tokens Tool Choice Tools Include Reasoning
Features

This model supports the following features:

Response Format Tools Reasoning Structured Outputs
Performance Summary

OpenAI: Codex Mini, a fine-tuned version of o4-mini for Codex CLI, demonstrates moderate speed performance, ranking in the 38th percentile across benchmarks. Its pricing is positioned at premium levels, falling into the 9th percentile. A standout feature is its exceptional reliability, achieving a 100% success rate with minimal technical failures. The model exhibits strong performance in several key areas. It achieves perfect accuracy in both Ethics and Reasoning benchmarks, with the latter also being the most accurate model at its price point and speed. General Knowledge is also a strength, with 99.5% accuracy. Furthermore, it shows high proficiency in Instruction Following (91st percentile), Mathematics (86th percentile), and Coding (94th percentile). A notable weakness is its performance in the Hallucinations benchmark, where it scored only 54.0% accuracy, indicating a tendency to provide answers rather than acknowledge uncertainty for fictional concepts. Email Classification is solid at 98.0% accuracy.

Model Pricing

Current Pricing

Feature Price (per 1M tokens)
Prompt $1.5
Completion $6
Input Cache Read $0.375

Price History

Available Endpoints
Provider Endpoint Name Context Length Pricing (Input) Pricing (Output)
OpenAI
OpenAI | openai/codex-mini 200K $1.5 / 1M tokens $6 / 1M tokens
Benchmark Results
Benchmark Category Reasoning Strategy Free Executions Accuracy Cost Duration
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