23.7
Intelligence Index
Above 79% of 106 other free models
Op
GPT-5.1-Codex
GPT-5.1-Codex is a specialized version of GPT-5.1 optimized for software engineering and coding workflows. It is designed for both interactive development sessions and long, independent execution of complex engineering tasks....
- Input
- text
- image
- Output
- text
Providers
Available through 1 free provider. Use the model ID and API settings below to connect.
Vercel AI Gateway
VAVercel AI Gateway
* The provider match may differ from this model. Check its docs for details.
Benchmarks
Compare scores and explore results by category.
Bars show scores from other free models on this site. The marker shows this model’s score. Comparisons include only models with a score for that index.
Scores from Artificial AnalysisFrequently asked questions
Free access, setup, and what to expect.
Free API access for GPT-5.1-Codex is listed through Vercel AI Gateway, but a specific request or token allowance isn’t available in the listed data. Check the GPT-5.1-Codex provider pricing and rate limits for what’s included and any account requirements.
To use GPT-5.1-Codex, choose one of the listed GPT-5.1-Codex API providers and follow the provider’s account and API-key setup guide. Copy the GPT-5.1-Codex model ID and connection settings for your chosen provider into your app or API client. Model IDs can differ between providers. API requests go directly to the provider; Free Models is a comparison site.
GPT-5.1-Codex accepts text and image as listed input formats. Listed output formats include text. Image or audio input support does not imply image or audio generation. Check the chosen provider’s GPT-5.1-Codex documentation for supported file types and request formats.
GPT-5.1-Codex has a listed context window of 400K tokens. Tokens are small pieces of content rather than a word count. Instructions, conversation history, and other inputs use context space, and the response also needs room. The maximum output length for GPT-5.1-Codex may be smaller than the context window and can vary by provider.
GPT-5.1-Codex has both reasoning and tool calling listed as supported capabilities. Reasoning enables additional processing for complex problems. Tool calling allows a model to request functions that your app executes. Check the chosen provider’s documentation for capability availability and setup.
Review the listed GPT-5.1-Codex benchmark results to compare performance on measured tasks. Compare scores within the same benchmark: coding indexes, Elo ratings, and win rates measure different things. The index comparison charts include only scored free models listed on Free Models. Evaluate GPT-5.1-Codex on examples from your own task alongside context size and provider limits.