GMX is a German webmail service with free and paid accounts. An account includes up to ten email addresses, an organiser with calendar, contacts, an online office suite and cloud storage with device synchronisation, backup and file sharing. Security covers a spam filter, antivirus and two-factor authentication. GMX offers a mobile app and the Mail Collector, which brings several mail accounts together in one place. Besides webmail, IMAP and POP3 are available. The free tier is funded by advertising. The service is delivered as SaaS.
GMX belongs to the Mail & Media segment of United Internet, a listed German company; the website names 1&1 Mail & Media GmbH as the publisher. According to United Internet, the applications run in company-owned data centres, and email and cloud data are stored exclusively in Germany under German and European data protection rules. No open-source licence is stated for the service. For a European organisation this means a German supplier with no foreign parent company and data storage inside the EU.