GPT-5 Codex
GPT-5 Codex is worth evaluating for coding, rag, and agents when its provider route and context window match the workload.
Use it for
- Teams evaluating coding, rag, and agents
- Workloads that can use a 400k context window
- Buyers comparing 2 tracked provider routes
Do not use it for
- Workloads where another current model has stronger sourced task evidence
- Family
- GPT-5
- Released
- 2025-10-01
- Context
- 400k
- Architecture
- Decoder Only
- Knowledge cutoff
- 2024-09
- Specialization
- code
- Openness
- Proprietary
- License
- ProprietaryCommercial use: conditional
- Weights
- Not released
- Code
- Unknown
- Training
- Pretrained
Cheapest of 2 routes · OpenRouter · cache read $0.130
About
GPT-5 Codex is OpenAI's coding-specialized variant of GPT-5, optimized for software engineering workflows, code generation, and agentic coding tasks at 400K context.
GPT-5 Codex is a proprietary model in the GPT-5 family. The structured metadata tracks a 400k-token context window, multimodal input, function calling, tool use, structured outputs, and code execution. This page tracks provider routes through Vercel AI Gateway and OpenRouter, with the cheapest tracked route listed at $1.25 input and $10 output per 1M tokens. No headline benchmark score is tracked for GPT-5 Codex yet.
Top use-case fit: coding, agents, and build tasks
Coding
Included by capability and metadata signals in the decision map.
RAG
Included by capability and metadata signals in the decision map.
Agents
Included by capability and metadata signals in the decision map.
Provider price ladder
Compare all 2Compare API pricing across 2 providers for input and output tokens, batch, and cached reads when available.
| Provider | Input / 1M | Output / 1M | Cache | Route |
|---|---|---|---|---|
| OpenRouter | $1.25 | $10.00 | read $0.130 | Serverless |
| Vercel AI Gateway | $1.25 | $10.00 | read $0.125 | Serverless |
Capabilities
Benchmark peer barsfor Coding
No task-mapped benchmark peers are available for this model yet.
Migration checks
No linked migration route is available for this model yet.
Frequently asked questions
What is the context window of GPT-5 Codex?
GPT-5 Codex has a context window of 400k tokens.
How much does GPT-5 Codex cost?
GPT-5 Codex is available at $1.25/1M input tokens through Vercel AI Gateway.
When was GPT-5 Codex released?
GPT-5 Codex was released on 2025-10-01.
Which providers offer GPT-5 Codex?
GPT-5 Codex is available from 2 providers: Vercel AI Gateway, OpenRouter.
Cheapest of 2 routes · OpenRouter · cache read $0.130