# GPT-5.3 Codex Spark

> GPT-5.3 Codex Spark is a proprietary language model from OpenAI, released on 5 Feb 2026. It accepts text, images and PDFs and generates text, with a 128K-token context window and up to 32K output tokens per response. As of 4 Oct 2026, the lowest listed API price is $1.75 per million input tokens and $14 per million output tokens (OpenAI API), across 1 provider we track.

Source page: https://www.aimodel.directory/models/gpt-5-3-codex-spark
Last verified: 4 Oct 2026

## Specifications

- **Developer:** OpenAI
- **Release date:** 5 Feb 2026 (source: models.dev, https://github.com/sst/models.dev/blob/dev/providers/openai/models/gpt-5.3-codex-spark.toml)
- **Status:** Generally available (source: models.dev, https://github.com/sst/models.dev/blob/dev/providers/openai/models/gpt-5.3-codex-spark.toml)
- **Weights:** Proprietary (API only) (source: models.dev, https://github.com/sst/models.dev/blob/dev/providers/openai/models/gpt-5.3-codex-spark.toml)
- **Context window:** 128K (128,000 tokens) (source: models.dev, https://github.com/sst/models.dev/blob/dev/providers/openai/models/gpt-5.3-codex-spark.toml)
- **Max output:** 32K tokens (source: models.dev, https://github.com/sst/models.dev/blob/dev/providers/openai/models/gpt-5.3-codex-spark.toml)
- **Knowledge cutoff:** 31 Aug 2025 (source: models.dev, https://github.com/sst/models.dev/blob/dev/providers/openai/models/gpt-5.3-codex-spark.toml)
- **Input:** Text, images and PDFs (source: models.dev, https://github.com/sst/models.dev/blob/dev/providers/openai/models/gpt-5.3-codex-spark.toml)
- **Output:** Text (source: models.dev, https://github.com/sst/models.dev/blob/dev/providers/openai/models/gpt-5.3-codex-spark.toml)
- **Reasoning mode:** Yes (source: models.dev, https://github.com/sst/models.dev/blob/dev/providers/openai/models/gpt-5.3-codex-spark.toml)
- **Tool calling:** Yes (source: models.dev, https://github.com/sst/models.dev/blob/dev/providers/openai/models/gpt-5.3-codex-spark.toml)
- **Structured output:** Yes (source: models.dev, https://github.com/sst/models.dev/blob/dev/providers/openai/models/gpt-5.3-codex-spark.toml)

## API pricing (USD per 1M tokens)

| Provider | Input | Output | Cached input | Context |
|---|---|---|---|---|
| OpenAI API | $1.75 | $14 | $0.17 | 128K |

## FAQ

### What is the context window of GPT-5.3 Codex Spark?

GPT-5.3 Codex Spark has a context window of 128,000 tokens (128K) and can generate up to 32,000 tokens in a single response, according to models.dev.

### How much does the GPT-5.3 Codex Spark API cost?

Through OpenAI API, GPT-5.3 Codex Spark costs $1.75 per million input tokens and $14 per million output tokens. Prices last verified 4 Oct 2026.

### Is GPT-5.3 Codex Spark open source?

No. GPT-5.3 Codex Spark is a proprietary model; OpenAI has not released its weights. It is available through APIs including OpenAI API.

### When was GPT-5.3 Codex Spark released?

OpenAI released GPT-5.3 Codex Spark on 5 Feb 2026, according to models.dev.

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Data licensed CC BY 4.0. Cite as: AI Model Directory, "GPT-5.3 Codex Spark", https://www.aimodel.directory/models/gpt-5-3-codex-spark