Here you will find selected questions/answers on various subject areas. If you do not find the right answer to your question about Contact Data Verifier, please contact us using the contact form.

Registration, utilization and payment

To use NCDV, register with NAVAX and data.mill

You will then receive a password by e-mail. You will then need your mail address and password for the data.mill programs to generate a license code and a so-called GUID.

NCDV is charged according to use. The more you use NCDV, the more credits will be charged by data.mill. The individual functions also cost a different number of credits. For example, checking a postal address costs 27 credits, while checking an email address costs 15 credits. Credits can be bought in the online shop of data.mill. The smallest unit is 50,000 credits, which cost EUR 75.00 (+ VAT). That means the listed above address check (27 credits) costs 0.0405 Euro, the check of the mail address 0.0225 Euro.

In the online shop you can pay either by invoice or via PayPal with credit card or other payment methods offered by PayPal. When paying via PayPal, the purchased credits will be immediately credited to the customer account, for a purchase on account only after receipt of your payment, which may take several days.

Yes, the system will automatically send you reminder emails regarding the declining credits.

Yes, if you consume more than 1 million data.mill credits per year, it is also possible to subsequently offset the credits. Please contact us for further details.

No, all data sent to data.mill will only be processed on the systems for the duration of the query (usually less than a second) and then deleted. They are also not stored in any protocol information.

Yes. Even if personal data is only for fractions of a second on our systems (for example, mail addresses or telephone numbers), there is legal processing. On request we will send you an order processing agreement according to Art. 28 GDPR.


Unless otherwise stated, features are available worldwide.
Notable restrictions are:

  • The verification of UID numbers: restricted to the EU + Switzerland
  • Checking mobile numbers: limited to GSM-based networks (about 90% of all mobile networks worldwide) except for a few network operators blocking such requests

The extension is available in german in english for the following countries:

  • Language ID 1031 Deutsch (Deutschland) DEU
  • Language ID 2055 Deutsch (Schweiz) DES
  • Language ID 3079 Deutsch (Österreich) DEA
  • Language ID 4103 Deutsch (Luxemburg) DEL
  • Language ID 5127 Deutsch (Liechtenstein) DEC
  • Language ID 2057 Englisch (Großbritannien) ENG
  • Language ID 3081 Englisch (Australien) ENA
  • Language ID 4105 Englisch (Kanada) ENC
  • Language ID 5129 Englisch (Neuseeland) ENZ
  • Language ID 6153 Englisch (Irland) ENI
  • Language ID 7177 Englisch (Südafrika) ENS
  • Language ID 8201 Englisch (Jamaika) ENJ
  • Language ID 9225 Englisch (Karibik) ENB
  • Language ID 10249 Englisch (Belize) ENL
  • Language ID 11273 Englisch (Trinidad und Tobago) ENT
  • Language ID 12297 Englisch (Simbabwe) ENW
  • Language ID 13321 Englisch (Republik Philippinen) ENP
  • Language ID 16393 Englisch (Indien) ENN
  • Language ID 17417 Englisch (Malaysia) ENM
  • Language ID 18441 Englisch (Singapur) ENE

Adress Functions

No, this exam is not possible. The address search only checks if the address exists. Even in countries with an existing registry, their data is incomplete or requires additional information that is not available (e.g. date of birth).

To a limited extent, yes. By default, NCDV returns an address in the local language, e.g. a Russian address in Cyrillic letters. However, the language can be selected via an additional parameter in the query. So "EN" brings in such cases an English variant of the address with Latin letters.

The conversion also works the other way around. If, for example, an address in Bangkok is entered in English, the result is converted by default into the respective national language and the usual alphabet, in this case Thai.

Phone Numbers

Phone numbers are brought into a standardized format. It can also be seen which area code it is and what kind of phone number it is. Unknown area codes are recognized this way. These cannot be useful phone numbers.

No, for landline numbers, this test is currently not possible via NCDV. While we are looking for opportunities, we have not yet found any that meet both telecom laws and data protection laws in Europe.

Email addresses

Some companies do a lot of work to prevent unwanted mail (spam). Therefore, their mail servers are configured so that they do not answer appropriate requests or allow the response to take so long that NCDV gives up in the meantime.

A "catch-all" domain is a special case of an unverifiable address. In this case, the company's mail server appears to accept each address and then check to see if it's deliverable. As a result, NCDV can make no statement about the deliverability.

Some mail servers require a mail to be sent in multiple attempts. It could be that a new test results in a different result some hours later.

Mail addresses in "disposable domains" are disposable addresses, which usually only exist for a few minutes and are used by some users, for example when registering on websites. An example would be mails in the domain "s-mail.com". It makes no sense to include these addresses in customer databases.

Yes, NCDV uses the web service of data.mill, which runs on internet servers and obtains information from there.

Further Services

For one-off larger data cleansing, merging of different data sources or automatic data processing please contact us. We are happy to assist you in your data cleansing project with our proven service from experienced consultants.