Existenz.ch Data APIs

These APIs are free for public and non-commercial usage, lovingly handcrafted by Christian Studer (Bureau für digitale Existenz). These APIs are unofficial. There is no guarantee of availability or top performance. They are actively monitored though.

Additional licencing restrictions may apply by the original data owner (For example MeteoSwiss or the BAFU).

Please don't abuse the APIs offered here. You are welcome to drop me a mail to cstuder@existenz.ch if you find them useful or need help.

For statistical purposes add &app={your app name} and optionally add &version={your app version} to all of your requests.

Do you like data to be easily accessible? Consider joining Opendata.ch, the Swiss section of the Open Knowledge Foundation.


See status.existenz.ch for basic status information.


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Available APIs

Time series APIs BAFU Hydrology API
SwissMetNet Weather Measurement API
Specialised APIs Aare.guru API
Legacy Aare API (Outdated, but still active)

Time series APIs

Time series share a common API, consisting of four methods for accessing locations, parameters, the latest values and date ranges for historical values.

BAFU Hydrology API

BAFU/FOEN (Bundesamt für Umwelt/Federal Office for the Environment) hydrology data from hydrodaten.admin.ch.

Measures water temperature, water flow and the surface height of rivers in Switzerland. No lakes though.

BAFU data needs to be credited and linked to the BAFU.

Periodicity: 10 minutes.

Open hydro API documentation Show hydro map and table

SwissMetNet Weather Measurement API

MeteoSwiss (Bundesamt für Meteorologie und Klimatologie/Federal Office of Meteorology and Climatology) offers a selection of their SwissMetNet data on the opendata.swiss portal.

Measures air temperatures, rain rate, winds, pressure, geopotentials and sunshine duration.

Note that most stations measure this 2 meters above ground, but some tower stations locate their sensors higher in the air. The parameters with suffix _tow are measured on tower stations.

Periodicity: 10 minutes.

Open smn API documentation Show smn map and table

Specialised APIs

Both old and new.

Do you need your own API? The Bureau für digitale Existenz can help.

Aare.guru API

Please refer to aareguru.existenz.ch for the APIs used by the urban swimming website and app Aare.guru.

Legacy Aare API (Outdated, but still active)

An old version of the BAFU Hydrology API is running on aare.schwumm.ch/api.

Please use the new BAFU Hydrology API instead.

Backend technology

This being a hobbyist project, boring technology is good. It's PHP and SQL.


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