Download
OpenAI .NET is the official client library for calling the OpenAI REST API from C# and other .NET languages, with first-class support for modern .NET patterns. It provides strongly typed clients across API areas (chat, audio, images, embeddings, moderations, batches, files, models, vector stores, responses, realtime, assistants) and works with .NET Standard 2.0 while the examples use .NET 8. You install it via NuGet and authenticate with an API key, ideally through environment variables or configuration rather than hardcoding. Every synchronous method has an async counterpart, and the library offers convenient streaming primitives for chat completions so you can process tokens as they arrive. It supports tool/function calling, structured outputs via JSON schema, audio input/output, image generation, embeddings, Whisper transcription, and assistants with retrieval augmented generation.
Features
- Strongly typed clients for chat, audio, images, embeddings, moderations, files, models, batches, vector stores, realtime, responses, assistants
- Async and streaming APIs for low-latency, token-by-token processing
- Tool calling and structured outputs with JSON schema constraints
- Audio input/output, Whisper transcription, and TTS support
- DI-friendly design, OpenAIClient factory, and protocol methods for raw access
- Built-in retries and testing support with model factories and virtual methods
Project Samples
