> 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.md).

# OS Net API

## What is OS Net API?

The OS Net API is a RESTful service provided by OS, enabling access to high-precision GNSS (Global Navigation Satellite System) data across Great Britain. It allows you to query data from OS Net reference stations, retrieve RINEX files, monitor station health and access metadata.

OS Net makes the accurate determination of national standard coordinates easier and more efficient for land surveyors than traditional (pre-GNSS) surveying methods. It is now possible to determine precise ETRS89 coordinates for your GNSS control stations with a single GNSS receiver, without ever leaving the survey site.

These coordinates can be instantly and precisely transformed to OSGB36, National Grid and ODN height coordinates. Therefore, a greater range of mapping, engineering and environmental projects can now use precise national coordinates that were never previously possible.

This API is designed to support developers, surveyors, and geospatial professionals who require accurate positioning data for tasks such as mapping, surveying and infrastructure monitoring.

{% tabs %}
{% tab title="Features" %}
**Station metadata access**

Retrieve detailed information about OS Net reference stations, including coordinates, elevation and transformation models.

**Network health monitoring**

Access hour-by-hour and day-by-day health status of the entire OS Net or individual stations.

**RINEX file retrieval**

Download RINEX v3 files for specific stations and time periods, supporting post-processing of GNSS data.

**Temporal and spatial filtering**

Query data using flexible time windows and geographic filters to tailor results to specific needs.

**Secure access**

Supports OAuth2 and API Key authentication for secure and controlled usage.
{% endtab %}

{% tab title="Benefits" %}
**Enhanced accuracy**

Enables centimetre-level positioning accuracy by leveraging OS Net’s dense reference network.

**Operational efficiency**

Reduces time and cost in field operations by providing reliable and timely GNSS data.

**Customisable queries**

Offers fine-grained control over data retrieval through spatial and temporal parameters.

**Improved monitoring**

Facilitates proactive maintenance and diagnostics with detailed station health insights.

**Seamless integration**

RESTful design and standard formats (JSON, RINEX 3) make it easy to integrate into existing workflows and systems.
{% endtab %}

{% tab title="Summary" %}

* **Format:** JSON, RINEX 3
* **Data Source**: OS Net
* **Coverage:** Great Britain
  {% endtab %}
  {% endtabs %}

## Things to remember for OS Net API

{% hint style="success" %}
You can:

* Obtain centimetre-level positioning accuracy
* Choose the spatial and temporal parameters you receive
* Obtain detailed station health insights to facilitate proactive maintenance and monitoring
* Integrate OS Net data into existing workflows and systems
  {% endhint %}

## What's next?

<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><strong>Getting started</strong></td><td>The getting started guide provides an overview of how to get started using the OS Net API, covering the core elements on how to automate the download of OS Net RINEX.</td><td><a href="/pages/UvI679uvN76OLZ05Rofw">/pages/UvI679uvN76OLZ05Rofw</a></td></tr><tr><td><strong>Technical specification</strong></td><td>The technical specification explains the methods that you can use to call the OS Net API.</td><td><a href="/pages/76IXdJEHM3U8HuJlBzxo">/pages/76IXdJEHM3U8HuJlBzxo</a></td></tr></tbody></table>


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