Open-source .NET CMS for building and managing websites, developed and commercially backed by a Danish company.

Umbraco is an open-source content management system originally created by Danish developer Niels Hartvig in 2005, built on the Microsoft .NET stack. The commercial entity behind it, Umbraco A/S, is headquartered in Odense, Denmark, and offers paid support, cloud hosting, and enterprise add-ons around the free open-source core.

The CMS is widely used by agencies and enterprises for corporate websites and intranets, with a large global community of developers and a partner network. Umbraco A/S also maintains a US office for the American market, but the registered legal headquarters and controlling operating entity remain in Denmark.