In this FAQ section, we aim to answer your questions regarding Phone Data Management when using DQ for Excel.

Whether you’re looking to learn more about the capabilities, the data behind the tools, the installation process, or pricing, you’ll find the answers here.

We’re committed to providing you with the information you need to make the most out of this powerful tool and elevate your customer data quality within Excel.

What is DQ for Excel?

DQ For Excel is a Microsoft Add-in that works right inside Microsoft Excel, it’s familiar and simple to use! Import data from almost any source, prepare it, master it and perfect it; then upload it back to almost any target. Process hundreds of thousands of records at once and only pay for your usage on a credit based model. 

DQ For Excel is powered by DQ on Demand, DQ Global’s Data Quality as a Service (DQaaS) Data Quality Improvement Platform. 

What is the difference between data Validation, Formatting, Verification and Authentication

Validation checks the syntactical validity of phone numbers, email addresses, I.P. address, URL’s and more. 

Formatting Corrects common formatting mistakes and ensure all your customer data follows the correct local formatting protocols to improve the quality, accuracy, and usability of your customer data. 

Verification Is the process of referencing your location data against reliable and trusted international postal authority data covering 240 Countries, to verify and add attributes like geo-codes and other useful location data. 

Authentication – Authentication is a silent process used to verify that email addresses or telephone numbers are legitimate and will deliver or dial 

Ensuring the deliverability of email addresses and dial-ability of phone numbers is essential for effective communication and maintenance of a reliable customer database. 

How can I ensure that my phone numbers will dial?

Our phone authentication capability will silently line test a telephone number to identify if it can be dialled or not and flag it accordingly 

Can I suppress phone numbers on the UK’s telephone preference list?

Yes – you can suppress individuals and businesses who have registered the UK’s Telephone Preference Service (TPS) or Corporate Telephone Preference Service (cTPS) 

How does silent phone number authentication work?

Our phone authentication service goes beyond simply checking the validity and format of a phone number, it performs a real-time line test, ‘ping, to determine if a phone number is active and will receive calls or texts. 

Can phone authentication be used to check mobile and landline numbers?

Yes, our phone authentication service can check for both mobile and landline phone numbers. However, not all countries support this capability. 

Does phone number validation work internationally?

Yes, our phone authentication capability is an international service with global coverage.  However, not all countries support this capability. 

Does phone validation work for business and personal numbers?

Yes, both business and personal phone numbers can be checked for validity. 

Can I standardise phone data?

You can standardize phone numbers and ensure they are of a common standard.

How long does it take to process?

Each service has different performance characteristics; however, it is generally very fast, and we continually optimise its performance 

How do I know how many credits have been used and remain?

Within DQ for Excel you simply check your balance under the account management section.  When you access this area, you will be shown your usage and balances.


What is the difference between DQ’s Capabilities and Solutions? 

The Capabilities consist of the DQ actions which can be performed on various types of data whilst the Solutions refer to the types of customer data the capabilities can be performed upon 

What are DQ for Excel’s capabilities?

Listed below are the capabilities (actions) that can be performed on various types of customer data to improve its quality:

  • Authenticate – Live testing of phones and emails for authenticity 
  • Compare – Compare data values in Excel 
  • Congruence -Check the alignment of data elements
  • Derive – Obtain new data from existing
  • Format – Correctly format your customer data
  • Parse– Split your phones, emails, etc. into its parts 
  • Suppress – Flag deceased, gone away, and do not call
  • Transform – Standardize your customer data
  • Validate – Check the syntax of email, phone, etc.
  • Verify – Confirm an Address exists worldwide
  • Generate – Create Phonetic Tokens for matching and Produce String Patterns for Analysis  
What are DQ for Excel’s Solutions to improve customer data?

Listed below are all the types of customer data that our capabilities (actions) can be performed upon to improve customer data quality:

  • Company – Acquire, Enrich and Refresh B2B Data
  • Country – Standardize and Derive additional country-related data
  • Email – Parse, Format, Validate, and Authenticate emails
  • Job Title – Standardize and Derive roles and levels
  • Location – Format, Verify, and Enrich international addresses
  • Person – Acquire, Format, Transform, Suppress, and Derive
  • Phone – Parse, Format, Validate and Authenticate phones
  • Postcode – Validate, Derive, and Format international postcodes
  • Website – Format, Parse and Enrich
Do you overwrite my existing phone numbers with the formatted ones?

This depends on your mapping of the output, whilst we do not recommend overwriting the original address it is possible. 
A better solution is to append the formatted phone numbers into new columns to the right of the existing phone numbers or place them in a fresh worksheet. 

Are records grouped for processing?

Records are processed in batches of 1,000 for all first party functions. 

Who can I contact for support using the application?

If you have any questions, please contact us at and we will get back to you as soon as possible. 

What elements make up an international phone dialling plan?

Each country has its unique system with its own set of rules and regulations. However, below is a general overview of how international telephone numbering plans work:

International Numbering Plan:

Most countries follow an international numbering plan, which includes:

  1. Country Code: Each country is assigned a unique country code by the International Telecommunication Union (ITU). For instance, the country code for the United States is “+1,” while the country code for the United Kingdom is “+44.”
  2. National Significant Number: Following the country code, there is typically a national significant number. This part of the number varies by country and can be further subdivided into regional or area codes, followed by the local subscriber number.
  3. Local Numbers: Local subscriber numbers are unique within a specific geographic area or city and are assigned by local authorities or telecommunications providers.
  4. Emergency Numbers: Most countries designate specific numbers, such as “911” in the United States, or 999 in the United Kingdom for emergency services like police, fire, and medical assistance.
  5. Special Service Codes: Certain numbers may be reserved for special services like directory assistance, customer service hotlines, and information services.
  6. Dialing Prefixes: To make domestic or international calls, you may need to use specific dialing prefixes. For instance, in the United States, you typically need to dial “1” before the area code and local number for long-distance calls.

Variable Numbering Plans:

While these elements are common, each country can have its variations. For example:

  • Some countries may not have area or regional codes.
  • Others may have variable-length local subscriber numbers.
  • Some countries use closed dialing plans, where you can only dial local numbers without the area code when calling within the same area.

It’s important to consult a local or international dialing guide when making calls to or from different countries to ensure you use the correct format.

Mobile Numbering Plans:

Mobile numbering plans often differ from fixed-line numbering plans. Mobile numbers typically have their own prefixes and are administered separately from fixed-line numbers. Mobile numbers may also have unique formats and may not be geographically bound.

Detailed information for each country’s numbering plan is typically maintained and regulated by the country’s telecommunications authority or regulatory body. If you need specific information for a particular country, it’s best to consult with local telecommunications providers or regulatory agencies.

What is a valid phone number?

The validity of a phone number varies depending on the country and the specific rules or conventions for phone numbers within that region.

However, there are some general guidelines and principles to consider when determining what constitutes a valid phone number:

  1. Country-specific format: Phone numbers are usually formatted differently in different countries. They may have varying numbers of digits, different area codes, and other regional variations. For example, in the United States, valid phone numbers typically have ten digits (excluding the country code), such as (555) 555-5555.
  2. Country code: International phone numbers include a country code, which is a prefix that helps identify the country the number is associated with. For example, the country code for the United States is +1 and the United Kingdom is +44
  3. Numeric characters: Phone numbers typically consist of numeric digits (0-9). Some phone systems allow additional characters such as spaces, hyphens, or parentheses to improve readability, but these are often not included when verifying the numeric portion of a phone number.
  4. No special characters: Phone numbers should not contain letters, special characters, or punctuation marks. They are primarily numerical.
  5. Length restrictions: Phone numbers have minimum and maximum length restrictions that vary by country and region. It’s essential to check the specific rules for the country in question.
  6. Validity of area codes: In many countries, specific area codes are reserved for particular regions or purposes. A valid phone number should adhere to the established area code rules for the given location.
  7. Emergency numbers: In many countries, certain phone numbers (e.g., 911 in the United States and 999 in the United Kingdom) are reserved for emergency services and should not be used for general communication.
  8. Mobile and landline numbers: Different rules may apply to mobile phone numbers and landline numbers, so it’s important to consider the type of phone number you are dealing with.

It’s crucial to verify phone numbers according to the specific rules and conventions of the country in question.

If you are designing a system or application that requires phone number to be valid, you should use the phone validate capability and format phone numbers based on the international dialing rules and standards, such as the ITU E.164 recommendation.

Which Countries does the validate, format and authenticate capabilitycover?

The validate, format, and authenticate services cover 240+ countries worldwide.

Are mobile, landline/fixed line and VoIP lines covered

Yes, our services can support any type of number: mobile, landline/fixed line, VoIP, etc.

What is the accuracy of phone authentication

With a multi-level approach that includes validation and authentication of phone numbers, we seek to ensure the highest level of dial-ability achievable for each telephone number.

Can a phone number be identified as landline or mobile?

Yes, it is possible to identify whether a phone number is associated with a landline or a mobile device.

The ability to make this determination depends on the specific numbering plan and regulations in the country or region where the phone number is registered, as some phone numbers may be associated with Voice over IP (VoIP) services, making it challenging to categorize them as strictly landline or mobile.

Can I identify a location from a phone number?

Yes, we can often identify the general location i.e. the town associated with a phone number, particularly the area code or the prefix, but determining an exact physical location (such as an address) solely from a phone number is not possible.


Written by Martin Doyle

Martin is CEO and founder of DQ Global, a Data Quality Software company based in the UK. With an engineering background, Martin previously ran a CRM Software business. He has gained a wealth of knowledge and experience over the years and has established himself as a Data Quality Improvement Evangelist and an industry expert.

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