tellows API – Partnership Program

tellows API – Partnership Program

Become a partner with the largest community phone number reverse search platform worldwide and benefit from our extensive database including millions of phone numbers. Gain access to our database for reported scam numbers in over 50 countries worldwide. Use our API for real-time requests and protect your company and customers with the knowledge of our data.

What is tellows?

  • tellows is a community project operating in over 50 countries worldwide as a leading phone number resource
  • Users rate phone numbers using our score model: the tellows score
  • Reported numbers display how trustworthy the number is and provide helpful information for other users
  • Our blacklist contains all of the negatively reported numbers
  • More than 7 million users visit tellows monthly
  • Numbers on tellows receive over 20.000 comments monthly
  • tellows is available for desktop, smartphones and tablets
  • The tellows app for real-time identification of callers is available for iOS and Android
what is tellows

Who uses tellows?

Over 7 Million users in over 50 countries use tellows every month. People who have been contacted by unknown callers look up the number in our database. They can leave a comment and warn other users. Others gain helpful information and learn how to deal with these phone calls.

tellows ABC markets worldwide – differentiated by the amount of visitors and reported numbers:

  • A markets are the most important tellows markets with 4.4m visits / month covering 80% of the total community; Germany, United Kingdom, Italy and France are the most important markets.
  • B markets are between 40.000 and 100.000 visitors / month
  • C markets contain less than 40.000 visits monthly
A markets B markets
Germany United States
Italy Taiwan
Indonesia Portugal
Brazil South Africa
United Kingdom Switzerland
France Poland
Spain Japan
Mexico Austria

tellows score

score calculation

The tellows score is classified by our community on a scale from 1 (where 1 is trustworthy) to 9 (where 9 is untrustworthy) and entails harassment calls including aggressive advertising. To calculate the scores, tellows uses a complex algorithm to arrange individual numbers, considering several factors and the users’ opinion. Therefore, all tellows users can see from a quick glance, whether the person calling is a trustworthy caller or not.

tellows API for blacklist integration

Our API solution provides you with all of the relevant data about phone numbers from tellows with just one request. Our live-API is suitable for integration into phone systems or app solutions. You can specify your output with several request parameters including the limitation to the country, language, tellows score and amount of comments. Our API documentation provides all necessary info about the scorelist API.

Receive data with the following details:

  • Phone Number
  • tellows score
  • Number of comments
  • Number of search requests
  • Caller type
  • Caller name (assigned by users)
  • Area (including ZIP code, city, country code)
  • Comments for each phone number
  • Set language for the result output
  • Deeplink to phone number
  • Filter results by score, country, comments or search requests

tellows caller types

Data Lifecycle of the Blacklist

Lifespan of Numbers on the Blacklist

what is tellows

The blacklist contains all numbers that have been reported or searched for within the last 30 days. One third of the numbers have a very short lifespan. The chosen criteria turn the blacklist into an up-to-date resource that only contains active numbers.

The API allows you to receive all relevant numbers in one request.

For more information contact us

tellows API Adapts to Your Needs

tellows API doc

The Scorelist API includes all currently reported phone numbers and its details defined with the parameters, to receive an up-to date blacklist in a CSV format. The scorelist API is the most purchased type of API in the tellows shop, as it provides stable protection by flexible access. This API is especially designed for Apps and PBX which work with a daily up-to-date blacklist.

The Live API provides real-time caller protection with live data, which includes all details about a phone number. Once the blacklist is downloaded, the Live API can be used to gather further information for every number on the blacklist with all possible caller names, caller types or comments etc. This service can be integrated into lookup services or widgets that need to provide live-data.

The Reputation API / Company API allows companies to track the caller history and customer satisfaction of company operatives. It is possible to target certain keywords that are associated with the company or track a list of numbers that are assigned to the company. Monitor the caller quality with the help of the tellows ratings. This service is especially designed for companies operating call centers or sales employees performing outbound calls. With the help of the tellows data, the service quality and reputation can be improved.

Add Comments to tellows with our Live API. In order to increase the database and let other users benefit from your solutions, you can send back ratings to tellows with your built application or software and help expand the tellows database. Comments and ratings reported by your software or application will be featured with your brand name.

More information about the tellows API on Medium

tellows Shop Products & Partners

Several companies, app developers and enterprises already use the tellows API. The tellows data has also been used for scientific research in the media and for university studies. The products and services of the tellows partners can be obtained in our shop, on the company homepage or in the app store.

tellows API Key for Developers

Thanks to the tellows API Key, programmers and telecommunications device developers are now able to query the tellows database through a telecommunications device (e.g. Asterisk). Regardless of whether you want to use the API Key as a real time block list or just to identify calls. Thanks to the great interest for the tellows score lists, we now want to offer the possibility of a real-time caller protection. With the help of the API Key and a suitable phone system this is no longer a problem.

For private usage the Live API key can be obtained in the tellows shop. Feel free to present us your developments in order to get featured on our website and earn yourself a free API-key for a limited time.

For small and medium sized enterprises we offer a API key accoring to the amount of channels in use. Visit our shop for more information.

Full Partner Portfolio

Contact Us

If you are interested in a partnership, please send us a message with your company details, your field of application and your use for the tellows data. We are happy to answer your questions.

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