EU CAPTCHA is a test intended to distinguish human from machine input. It prevents the use of bots/machines (e.g. for automated account creation) in the framework of services provided by EU Institutions.
Distributed under the EUPL-1.2 licence, EU CAPTCHA is available from the EC Gitlab as an open source API and can therefore be used by everyone (public or private entities) for securing web services through a user friendly and multilingual solution.

The API supports three types of CAPTCHA:

• Alphanumeric CAPTCHA with audio transcription;
• Image rotation CAPTCHA.
• Sliding CAPTCHA.

Why EU CAPTCHA?

Several CAPTCHA solutions exist on the market, either provided as components or as services. Unfortunately, they all have one or more of the following shortcomings:

• They provide an insufficient level of security with a high rate of false positives;
• They provide an insufficient level of user friendliness with a high rate of false negatives;
• They are not or insufficiently maintained;
• They do not support internationalisation or multilingualism and, in particular, they do not support all official languages of the European Union;
• They do not support users with disabilities;
• They do not have a licensing model that is compatible with EUPL and, in particular, they cannot be distributed as part of systems provided by public administrations;
• They raise ethical concerns because they collect private data or provide puzzles whose resolution creates commercial value.

The objectives of the action initiated under the ISA programme for providing EU-CAPTCHA are:

1. providing (for free) an open source component, operable as a service;
2. a secure and user friendly solution;
3. multilingual with support for all official languages from the European Union;
4. accessible by users with disabilities;
5. compliant with the highest level of data protection rules and best practices;
6. maintained with continuous support for subsequent versions of the Java Virtual Machine.

More information: https://code.europa.eu/eu-captcha/EU-CAPTCHA