OpenAI: GPT-5.3-Codex
OpenAI's GPT-5.3-Codex is an advanced AI model capable of processing text, images, and files, with a context length of 400,000 tokens and the ability to reason and handle tools, making it versatile for complex tasks. However, structured output support is not available, which might limit its use in specific applications. Given its blended benchmark score of 73.4 across one independent test, this model competes well in general AI tasks. Its pricing at $1.75 per million input tokens and $14 per million output tokens positions it as a higher-cost option compared to some alternatives but offers robust performance for those needing extensive processing capabilities.
Benchmark results
Independent, published benchmarks. Blended score 73.4 across 1 benchmark, last refreshed 2026-07-23. How scoring works →
| Benchmark | Measures | Score |
|---|---|---|
| AI Index | broad capability composite | 73.0 |
- 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.