概要

OpenAI Codexは、自然言語プロンプトを数十のプログラミング言語にわたってコードに変換することができるGitHub Copilotの背後にあるAIモデルです。GPTアーキテクチャに基づき、公開コードの数十億行で学習され、CodexはPython、JavaScript、TypeScript、Goで優れています。OpenAIのAPIを通じてコード生成、補完、説明機能を提供します。

ツール詳細 有料

料金 API pricing (pay-per-token)
API利用可能 はい
4.6
1 reviews
Output Quality
4.7
Ease of Use
4.6
Feature Set
4.6
Value for Money
4.5
Reliability
4.4
Claude Opus 4.6
AI Review
4.6/5

OpenAI Codex remains one of the most influential AI coding models, serving as the foundation behind GitHub Copilot and numerous code generation tools. Built on GPT architecture and trained on billions of lines of public code, Codex excels at translating natural language prompts into functional code across dozens of programming languages, with particular strength in Python, JavaScript, and TypeScript.

The API-first approach offers excellent flexibility for developers building custom integrations, and the pay-per-token pricing model keeps costs manageable for varying workloads. Code completion, generation from docstrings, and cross-language translation are standout capabilities.

However, Codex isn't without limitations. It can occasionally produce subtly incorrect or insecure code, requiring careful human review. The pay-per-token model can also become expensive at scale compared to flat-rate alternatives. Additionally, newer competitors like Claude and open-source models such as Code Llama are closing the gap rapidly.

Overall, Codex delivers a powerful, well-documented coding AI with strong ecosystem support, making it a top-tier choice for developers seeking reliable AI-assisted code generation.

Output Quality
4.7
Ease of Use
4.6
Feature Set
4.6
Value for Money
4.5
Reliability
4.4
Feb 15, 2026
OpenAI Codex Screenshot

Added: Feb 15, 2026

openai.com/index/openai-codex

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