> For the complete documentation index, see [llms.txt](https://docs.os.uk/os-apis/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.os.uk/os-apis/accessing-os-apis/os-net-api/technical-specification.md).

# Technical specification

The **OS Net API** provides programmatic access to Ordnance Survey’s high-precision GNSS reference network across Great Britain. It enables developers and geospatial professionals to retrieve station metadata, monitor network health, and download RINEX v3 data files for post-processing and analysis.

This API is ideal for applications in surveying, mapping, infrastructure monitoring, and any domain requiring centimetre-level positioning accuracy.

## Base URL

```
https://api.os.uk/positioning/osnet/v1
```

### Authentication

The API supports the following authentication methods:

* **OAuth2** (Client Credentials flow)
* **API Key in Query Parameter**
* **API Key in Header**

### OS Net API

Operations providing access to OS Net:

<table data-view="cards"><thead><tr><th></th><th></th><th data-hidden data-card-target data-type="content-ref"></th></tr></thead><tbody><tr><td><h4><strong>Stations</strong></h4></td><td>Returns a list of OS Net stations, optionally filtered by time and location.</td><td><a href="/os-apis/accessing-os-apis/os-downloads-api/technical-specification/opendata-products.md">OpenData products</a></td></tr><tr><td><h4><strong>Rinex</strong></h4></td><td>Return list of years with available RINEX data.</td><td><a href="/os-apis/accessing-os-apis/os-downloads-api/technical-specification/download-an-opendata-product.md">Download an OpenData product</a></td></tr><tr><td><h4>Rinex Zip</h4></td><td>Provides an endpoint to download many RINEX files as a single zip archive.</td><td><a href="/os-apis/accessing-os-apis/os-net-api/technical-specification/rinex-zip.md">Rinex Zip</a></td></tr><tr><td><h4>Models</h4></td><td>Defines the request parameters and response objects used by the OS Net API.</td><td><a href="/os-apis/accessing-os-apis/os-net-api/technical-specification/models.md">Models</a></td></tr></tbody></table>


---

# Agent Instructions
This documentation is published with GitBook. GitBook is the documentation platform designed so that both humans and AI agents can read, navigate, and reason over technical content effectively. Learn more at gitbook.com.

## Querying This Documentation
If you need additional information that is not directly available in this page, you can query the documentation by asking a question.

Perform an HTTP GET request on the following URL with the `ask` and `goal` query parameters:

```
GET https://docs.os.uk/os-apis/accessing-os-apis/os-net-api/technical-specification.md?ask=<question>&goal=<user_goal>
```

`ask` is the immediate question: it should be specific, self-contained, and written in natural language.
`goal` is what the user is ultimately trying to achieve, the reason they need the answer. Sharing it helps GitBook give you a better, more relevant answer. A goal is most helpful when it describes the outcome the user wants rather than restating the question. For example, with `ask=how do I create an API token`, a goal like `automate deployments from our CI pipeline` lets GitBook tailor the answer to that use case.

The response will contain a direct answer to the question and relevant excerpts and sources from the documentation.

Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.