Phone Number Validation

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Hi Everyone, I need to develop a service which tells me whether a given phone number is in service and is valid or not. It can be international number. This is basically to clean the list of leads we have. Is there any service which can give me the required information?

I currently have an international numbering plan database which only tells me if the given phone number is in valid format up to a certain area code. But I need to know whether it will ring or not. Any help will be appreciated.


Best Ragards Rizwan H Qureshi

V: +44 (0) 7544180726

4 thoughts on - Phone Number Validation

  • Hi!

    I am doing something similar. Country codes are available from ITU-T. Country codes are available for every country, except for the North American Numbering Plan, which covers essentially North America. NANP numbers have a simple structure (with little oddities), which is not generally valid outside their domain, so it is difficult to check the validity of numbers
    (unless you are willing to work through the regulations of every country you want to cover).

    For example, a complete German phone number, including the equivalent of NPA and NXX, can be between 5 and 15 digits. The system is (almost) strictly hierarchical, but requires detailed knowledge, i.e. you do need an algorithm that figures out the area code. There are also separate number ranges for mobile phone numbers.

    In practice there can be more than 15 numbers, depending on the country, and whether the regulators are not particularly strict in enforcing a specific length of phone numbers (for ISDN

    Generally, you cannot know whether dialing a number will ring the other end, or not. If all channels are already occupied for a T1 or E1 connection, the last exchange station will already signal unavailability, i.e. “user busy” may be signaled by the user or the network.


  • Sounds like a service that spammers have been searching for since Alex called Tommy and asked him to “Come here.”

    Such a service is impossible. There is no way to tell if a number will be answered without actually calling it. Even then you don’t know whether an out of service is temporary or permanent.

  • There is exactly one way to find out whether or not a given telephone number will answer: Dial it.