GPT-5 Codex Model Specs, Costs & Benchmarks (July 2026)
GPT-5 Codex, developed by OpenAI, features a context window of 400K tokens. The model costs $1.25 per million tokens for input and $10.00 per million tokens for output. It was released on September 23, 2025, and has achieved impressive scores in various benchmarks.
Access GPT-5 Codex & 210+ other AI models all in one platformTry Magica for free
Overview
 GPT-5 Codex | |
|---|---|
Model Provider The organization behind this AI's development | OpenAI |
Input Context Window Maximum input tokens this model can process at once | 400K tokens |
Output Token Limit Maximum output tokens this model can generate at once | 128K tokens |
Release Date When this model first became publicly available | September 23, 2025 10 months ago September 23rd, 2025 |
Knowledge Cutoff Latest training-data date reported by the provider | September 30, 2024 |
Pricing
| GPT-5 Codex | |
|---|---|
Input Token Cost Cost per million input tokens | $1.25 per million tokens |
Output Token Cost Cost per million output tokens | $10.00 per million tokens |
Web Search Cost Additional cost for each web search operation | $0.01 per search |
Cache Read Cost Cost to reuse cached input tokens | $0.13 per million tokens |
Capabilities & Features
| GPT-5 Codex | |
|---|---|
Input Types Supported input formats | textimage |
Output Types Supported output formats | text |
Tokenizer Text encoding system | GPT |
Key Features Advanced capabilities | ✓ Function Calling✓ Structured Output✓ Reasoning Mode✓ Content Moderation |
Reasoning Controls Defaults and configurable reasoning effort | Always enabled |
Benchmarks
| GPT-5 Codex | |
|---|---|
Best Design Arena Score Highest human-preference Elo score across design arenas | 1,138 Elo (#26 in Webapps (52.4% win rate)) |
Compare This Model
See how GPT-5 Codex compares with other top models
Compare GPT-5 Codex with top models in each category:
🚀Programming
Best models for coding and development
🎨Creative & Roleplay
Models optimized for creative writing
📢Marketing
Content creation and marketing tasks
💻Technology
Technical analysis and explanations
🔬Science
Scientific research and analysis
🌐Translation
Multilingual translation tasks
