There are many agencies that deliver scuba diving certifications. Most major agencies recognized levels from most of the other ones. Some committees are also formed to ensure equivalence of levels. This allows individuals to start with an agency and continue with another one.
Online validations systems for diving agency
Here are a list of links to the pages or systems for verifying divers and or dive professionals credentials. Agencies are listed in alphabetical order.
Access to the certification and information
Not many agencies are providing this information and with new laws such as the GDPR in Europe, we might see less. For most this data is accessible to professionals affiliated with their respective agencies. Recently most agencies have been providing their divers with certification in an electronic format. Divers can carry their certifications on their mobile devices and can log in the system of the agencies they are certified with.