OpenAI: GPT-5.3-Codex
The OpenAI GPT-5.3-Codex is a multifaceted AI model that supports three input modalities: text, image, and file. It has a significant context length of 400,000 tokens, allowing for in-depth analysis and understanding. Additionally, it can be used with tools, and its reasoning capabilities make it suitable for complex tasks. Given its price point, the OpenAI GPT-5.3-Codex may be worth considering for users who require a high level of performance across various benchmarks. Its blended benchmark score of 64.4 across one independent benchmark indicates competitive standing in its class. However, at $1.75 per million input tokens and $14.0 per million output tokens, it is not the most cost-effective option, particularly for those on a tight budget or with limited computational resources.
Benchmark results
Independent, published benchmarks. Blended score 64.4 across 1 benchmark, last refreshed 2026-09-07. How scoring works →
| Benchmark | Measures | Score |
|---|---|---|
| AI Index | broad capability composite | 60.9 |
- Model ID
- openai/gpt-5.3-codex
- Vendor
- openai
- Released
- February 2026
- Tokenizer
- GPT
- Input Modalities
- text, image, file
- Output Modalities
- text
- Max Output
- 128,000 tokens
- Tool Calling
- ✓ supported
- Structured Output
- ✓ supported
- Reasoning Mode
- ✓ supported
- Vision
- ✓ accepts images
- Audio
- no
- Moderated
- yes
What it costs in practice
Computed from the current $1.75/M input and $14.00/M output rates. Run your own numbers →
| Job | Tokens | Cost |
|---|---|---|
| Summarize a 50-page report | 30k in / 1.5k out | $0.07 |
| Classify 1,000 customer emails | 500k in / 50k out | $1.58 |
| A month of a busy support chatbot | 5M in / 2M out | $36.75 |
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Quick answers
- How much does OpenAI: GPT-5.3-Codex cost?
- $1.75 per million input tokens and $14.00 per million output tokens.
- What is OpenAI: GPT-5.3-Codex's context window?
- 400,000 tokens, roughly 600 pages of text in a single request.
- Does OpenAI: GPT-5.3-Codex support tool calling?
- It supports tool calling, structured output, a reasoning mode.
- Can OpenAI: GPT-5.3-Codex process images?
- Yes, it accepts image input.