Zeugnischeck

The "Witness Check" app:

In view of prices under ten euros for a master craftsman's certificate with seal and signatures, which are freely advertised on the websites of Chinese companies, abuse is likely to increase further in the future. An increasing number of forged master craftsman's certificates are not only being presented in chambers of crafts, which usually first have to be verified by calling the issuing chamber.

With the help of our "Zeugnischeck" app, a submitted master craftsman's certificate or a master craftsman's certificate can be checked quickly and easily. All you have to do is enter the data from the certificate or send it by scan:
• Surname, first name and date of birth of the examinee
• Issuing chamber of crafts, craft, completion date and all four partial grades (or exemptions).

If the certificate has a QR code that already contains this data, entering the data can be replaced by a scan. Even the smallest changes to the input lead to a completely different hash value. A conclusion from a hash value to the associated input data is only possible with decades of computing effort.

No personal data is stored either in the app or on the database with which the app communicates. The database only contains the hash values ​​of the valid test certificates. These result from the application of a mathematical one-way function to the data in the test certificates. Even if someone knows a valid hash value, they cannot determine the associated certificate data.