OpenAI: GPT-5.3-Codex
Analysis Summary
OpenAI: GPT-5.3-Codex sits in the Professional tier on our leaderboard, ranked #6 of 565 published models on overall intelligence. At $1.75 input and $14.00 output per 1M tokens, it is among the most expensive on the market. It offers a generous context window for extended reasoning and code review and supports tool use, function calling, vision, and reasoning.
Editorial notes
GPT-5.3-Codex from OpenAI delivers frontier coding and reasoning with strong agentic performance, vision support, a 400K context window, and reliable tool use for complex business automation.
Assessed May 31, 2026
Rankings consider pricing, capabilities, benchmarks, and real-world applicability and are refreshed as new models launch. Feedback?
Performance Profile
How OpenAI: GPT-5.3-Codex compares
OpenAI: GPT-5.3-Codex ranks #11 of 371 AI models we track for overall intelligence, #7 of 308 for coding, #13 of 283 for agentic tasks. Its 400K-token context window is larger than 86% of the models we list. At $1.75 per million input tokens it is cheaper than 17% of comparable models.
About OpenAI: GPT-5.3-Codex
GPT-5.3-Codex is OpenAIās most advanced agentic coding model, combining the frontier software engineering performance of GPT-5.2-Codex with the broader reasoning and professional knowledge capabilities of GPT-5.2. It achieves state-of-the-art results..
Capabilities
Performance Indices
Source: Artificial Analysis
Benchmark Scores
Intelligence
Technical
Content
Benchmark data from Artificial Analysis and Hugging Face
How does OpenAI: GPT-5.3-Codex stack up?
Compare side-by-side with other professional models.
Model Information
| OpenRouter ID |
openai/gpt-5.3-codex
|
| Provider | openai |
| Release Date | February 24, 2026 |
| Context Length | 400,000 tokens |
| Max Completion | 128,000 tokens |
| Status | Active |
Pricing
| Token Type | Cost per 1M tokens | Cost per 1K tokens |
|---|---|---|
| Input | $1.75 | $0.001750 |
| Output | $14.00 | $0.014000 |
Live Performance
Live endpoint metrics, refreshed every 30 minutes.
Leaderboard Categories
External Resources
Frequently asked questions about OpenAI: GPT-5.3-Codex
How much does OpenAI: GPT-5.3-Codex cost?
OpenAI: GPT-5.3-Codex costs $1.75 per million input tokens and $14.00 per million output tokens.
What is the context window of OpenAI: GPT-5.3-Codex?
OpenAI: GPT-5.3-Codex has a context window of 400,000 tokens (400K).
Is OpenAI: GPT-5.3-Codex good for coding?
On our coding benchmark index, OpenAI: GPT-5.3-Codex ranks #7 of 308 models, placing it in the top quartile of the field for code generation and debugging.
What can OpenAI: GPT-5.3-Codex do?
OpenAI: GPT-5.3-Codex supports image/vision input, tool use, and function calling.
Who created OpenAI: GPT-5.3-Codex?
OpenAI: GPT-5.3-Codex is developed by OpenAI and was released on February 24, 2026.
