As of 15 January 2024, we have withdrawn a number of APIs.

The ADMIRALTY AVCS Online Discovery API, Tidal Discovery API, Tidal Foundation API and Tidal Premium API are still available to access below.

If you have any queries or wish to discuss specific future API usage, please contact the products team.

ADMIRALTY API Developer Portal

Access on demand a selection of APIs through the ADMIRALTY API Developer Portal. In addition to a range of marine information including fishing limits, marine protected areas, port limits and more, the portal contains documentation and code snippets to help you get the most out of the API when developing and launching solutions.

AVCS Online Discovery API

The AVCS Online Discovery API provides free access to a trial version of the AVCS Online Web Map Service (WMS) and is intended for use by developers from organisations who are interested in becoming re-sellers of AVCS Online. The Discovery API provides you with Electronic Navigational Charts (ENCs) along the south coast of England. 

Tidal API

The Tidal API provides access to tidal predictions for the coastline of the British Isles and Ireland, built using accurate and reliable data from the country's largest network of tidal stations. There are three subscription options available, allowing you to build tidal height and time predictions into your own applications, according to your requirements. 

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At the UK Hydrographic Office, we specialise in marine geospatial data to support safe, secure and thriving oceans. We source, analyse and process data from seabed to surface, to help partners around the world make the best use of our marine environment.

Our suite of Application Programming Interfaces (APIs) allows you to make informed decisions and develop your own solutions, unlocking the potential of a wide range of marine data from around the UK.

You can find our selected range of APIs on the ADMIRALTY API Developer Portal, where you can discover a range of data and web services. Specific access can be requested on demand.