Caller ID Lookup: How to check caller ID and is it free?

Last Update : 03.11.23 • Publication : 18.08.23 • Reading :

Over 7 billion people have cell phones and every second, thousands of calls are made. The sound of incoming calls is now a big part of our daily lives. But with the convenience of instant communication comes the frustration of unknown caller disrupting our routines.

For individuals, unknown calls are a nuisance; for businesses, they're a significant challenge. In the business world, where time directly translates to value, not knowing who's on the other end can be costly.

But thanks to Caller ID Lookup, you can find out who called and regain control of your phone and stop wasting time on unnecessary or unwanted calls. 

What is Caller ID Lookup?

Caller ID (Caller Identification) Lookup is a digital service that lets you reveal the essential information behind a caller's number. These services are also known as "Reverse phone number lookup", "Caller ID Check" or sometimes mistakenly "Phone Number Lookup". This technology enables users to identify the person calling.

What Caller ID Lookup services are available?

Theses services come in various forms to cater to different user preferences and technological requirements. Let's explore the three primary types available:


APIs are designed for developers and businesses who want to integrate this functionality into their own applications or services. APIs provide a standardized way for external systems to request and receive caller information. Developers can access the service's database and retrieve data to display within their applications.

Caller ID API

This solution requires some development knowledge to set up, but allows real-time searches and is compatible with any system.


Good news : If you're looking for a reliable solution, discover our Caller ID API that allows you to search a dataset of over 350 millions phone numbers and get results in less than 20ms.
Additionally, we also provide the complementary reverse service —a phone number lookup API for retrieving phone numbers using names, addresses, and more.

Mobile Applications

Mobile applications are designed to be installed and used directly on smartphones and other mobile devices. These apps perform real-time lookups and provide caller information instantly. Users can receive detailed insights about incoming calls directly on their device screens.

Mobile App Caller ID

These applications have the advantage of being real-time, but they are only compatible with smartphones. In the case of companies with fixed-line telephones, these will be of no use.

Web Applications

Web-based services function through internet browsers, allowing users to access the service from any device with an internet connection. These web applications offer similar functionalities to mobile apps but are not limited to a specific platform.

Web Caller ID Lookup

Users can visit the service's website, make a quick search to identify unknown callers, and receive detailed information about the caller. But these applications have the disadvantage of not being real-time, as they require human input.

What data is associated to it?

These services determine which phone number belongs to which company based on 3 main type of information retrieved during the lookup process:

  • Caller's Name: One of the primary pieces of information is the caller's name, if available.
  • Location: Identify the geographical location associated with the incoming number.
  • Business name: For business phone numbers, It can often provide details about the organization or company associated with the caller.

Depending on your business-specific needs, some services, like ours, have additional options and can provide you with more b2b data associated with the phone number (not only the business name and location).  Find more information here: Business Search API.

This may include more contact data, such as e-mail addresses, and information on revenues, URLs, company size, or legal status.

How are Caller ID Lookup tools used?

The tools offer a multitude of practical applications that cater to diverse needs and situations. Let's explore some of the key usages of these tools, demonstrating how they can be invaluable assets in various scenarios:

  • Avoiding Spam Calls: Identify spam and scam calls. The tool make a phone number search in the database and can quickly indicate if it's a known spam number, allowing you to avoid potential scams. Some services offer auto block spam calls.

Block Spam

  • Identifying Important Contacts: Through the service, you can find out which phone number belongs to which company, ensuring you recognize important business contacts and don't miss crucial opportunities.
  • Filtering Robocalls: Flag robocalls, which are automated calls delivering pre-recorded messages.
  • Enhancing Customer Service: When a customer calls a support line, the system can retrieve their information, allowing agents to address the caller by name and quickly access their history with the company.
  • Blocking Unwanted Callers: Identify persistent telemarketing calls and block these numbers on your phone.

By offering real-time information about incoming callers, these tools empower users to manage their calls effectively, protect their privacy, and enhance their overall calling experience.



Yes, there are both paid and free Caller ID Lookup services available. Many mobile apps and web applications offer basic functionality at no cost. But even though these free services can be reliable, they are generally manual searches, with a limited number of searches per day. Useful for identifying a missed call, useless for filtering calls in real time.

What is reverse Caller ID Lookup?

Reverse Caller ID Lookup is the process of searching for the identity and information of a caller using their phone number, as opposed to the traditional method of searching for a name and finding the associated phone number.


Using Reverse phone number lookup Lookup services to identify incoming callers is generally legal and safe, as the information is sourced from publicly available databases. However, it is essential to ensure that the service used complies with privacy regulations and use the service responsibly.


Free Phone Number Lookup tools can help users identify spam callers. However, while paid services might offer the capability to block or report these numbers directly, most free services do not provide such options. Even so, identifying spam or scam numbers can still enable users to take measures to avoid these calls in the future.

How to choose a reliable Reverse Phone Lookup Service?

When selecting a Reverse Phone Lookup service, consider factors such as the service's reputation, user reviews, data sources, and data accuracy. Additionally, opt for services that prioritize user privacy and data security to safeguard your personal information while using the service.

How accurate are Caller ID Lookup Tools?

While the accuracy of these tools can vary based on the source of their data, many reputable services offer a high degree of accuracy. It's essential to choose a well-reviewed and trusted service for the most accurate results.

Marc Wahba
Author Marc Wahba

Meet Marc, the co-founder and CTO of Infobel. He is in charge of software development. In 1991, he obtained a degree in civil electromechanical engineering from the Polytechnic Faculty and later earned a master's degree in management from the Solvay School of Brussels. Along with his brother, he founded Infobel in 1995, which was the first online directory to offer an online white pages directory. Marc's innovative mindset has led to the launch of new data products and services that have become a global success, serving clients all over the world.