GPT-5-Codex
Summary
GPT-5-Codex is a proprietary language model from OpenAI, released on 15 Sept 2025. It accepts text and images and generates text, with a 400K-token context window and up to 128K output tokens per response. As of 4 Oct 2026, the lowest listed API price is $1.25 per million input tokens and $10 per million output tokens (Azure AI Foundry), across 2 providers we track.
Coding-optimized GPT model for repository edits, reviews, and agentic software work
Last verified 4 Oct 2026. Every figure on this page links to its source.
Specifications
| Developer | OpenAI |
|---|---|
| Release date | 15 Sept 2025 [models.dev] |
| Status | Generally available [models.dev] |
| Weights | Proprietary (API only) [models.dev] |
| Context window | 400K (400,000 tokens) [models.dev] |
| Max output | 128K tokens [models.dev] |
| Knowledge cutoff | 30 Sept 2024 [models.dev] |
| Input | Text and images [models.dev] |
| Output | Text [models.dev] |
| Reasoning mode | Yes [models.dev] |
| Tool calling | Yes [models.dev] |
GPT-5-Codex API pricing by provider
USD per million tokens. Sorted by input price.
| Provider | Input | Output | Cached input | Context | Source |
|---|---|---|---|---|---|
| Azure AI Foundry gpt-5-codex | $1.25 | $10 | $0.13 | 400K | models.dev, 4 Oct 2026 |
| Vercel AI Gateway openai/gpt-5-codex | $1.25 | $10 | $0.13 | 400K | models.dev, 4 Oct 2026 |
Frequently asked questions
What is the context window of GPT-5-Codex?
GPT-5-Codex has a context window of 400,000 tokens (400K) and can generate up to 128,000 tokens in a single response, according to models.dev.
How much does the GPT-5-Codex API cost?
GPT-5-Codex is listed from $1.25 per million input tokens and $10 per million output tokens (Azure AI Foundry). Prices last verified 4 Oct 2026.
Is GPT-5-Codex open source?
No. GPT-5-Codex is a proprietary model; OpenAI has not released its weights. It is available through APIs including Azure AI Foundry, Vercel AI Gateway.
When was GPT-5-Codex released?
OpenAI released GPT-5-Codex on 15 Sept 2025, according to models.dev.
Which providers offer GPT-5-Codex?
We track GPT-5-Codex on 2 providers: Azure AI Foundry, Vercel AI Gateway.
Change history
No changes detected since we started tracking this model. We re-check every source daily.