This script is designed to check if phone numbers exist in WhatsApp. It analyzes the numbers specified in the phones.csv file and classifies them into existing numbers in WhatsApp (exist_phones) and non-existing numbers (not_exist_phones). This checker is designed to check numbers for whatsapp installed on them. Validate any numbers from any country. Identify which phone numbers are active and those that are not able to receive whatsapp messages. Optimize your resources and save time and money.
- Make sure you have Node.js installed.
- Clone the repository or download the source files of the script.
- open the
phones.csvfile. - Write down the phone numbers you need to check. One line - one phone.
This tool was created using our public API that you can access too with your Whapi.Cloud account. It takes 3 steps to get started to use WhatsApp API with Whapi.Cloud. You will need a phone with WhatsApp Business or regular WhatsApp. Access is granted for 5 days free of charge. Pair your number via QR code in your account
In the file
config.jsonyou need to insert the token from your personal account Whapi.Cloud, as well as the number you want to check. It also shows the limits we recommend to use.daily_limitis how many checks are left (Filled automatically), andrefreshed_limitis how much of the limit is set on refresh.last_limit_refreshshows the date the limits were last updated (Filled automatically). Thedelayargument determines the frequency of checks. Andchecks_per_delayis responsible for the number of numbers that will be checked during the check.
Open a terminal or command prompt in the folder with the script.
Run the following commands to install the necessary dependencies and compile the script:
npm i
Run the script with the command:
npm run start
When the script finishes, you will get two files with results: invalid.csv and valid.csv, where numbers will be filtered accordingly.
The invalid.csv file will contain numbers that do not have WhatsApp.
The valid.csv file will contain numbers that have WhatsApp.
The unlimited.csv file may appear if there are numbers left that are outside the daily limit you have set in the settings. This will allow you to continue working on checking numbers using this file.
WhatsApp number checking works by verifying whether a phone number is registered on the WhatsApp platform. From a user perspective, this is similar to what happens when you try to start a chat with a phone number in WhatsApp: if the number is not registered, WhatsApp clearly indicates that the user is not on WhatsApp. Whapi.Cloud performs this check programmatically via an API channel. Instead of using the WhatsApp user interface, the API communicates with WhatsApp through an active, linked WhatsApp session using real-time sockets. The connected WhatsApp number sends a lightweight availability request and receives a response indicating whether the target number exists on WhatsApp.
Like any activity on WhatsApp, very aggressive or unnatural behavior — such as checking large volumes of numbers instantly without pauses — can increase the risk of restrictions or account bans. WhatsApp actively monitors usage patterns. To reduce this risk, Whapi.Cloud provides configurable limits in both the web interface and the open-source checker script. You can control batch size, delays between checks, and overall speed to keep activity within safe and realistic patterns.
If you prefer not to connect your own WhatsApp number or want to avoid operational risks, you can order a done-for-you bulk number check. In this case, our team processes your list using our infrastructure and delivers clean results without requiring you to run checks yourself. Contact our team to find out more and order this service: care@whapi.cloud
https://support.whapi.cloud/help-desk/getting-started/getting-started
Registration. The first step is to register on the Whapi.Cloud website and create an account. It's free and doesn't require you to enter a credit card. After registration you will immediately have access to a test channel with a small limitation. Wait for it to start (it usually takes about a minute). You will need to connect your phone for Whatsapp automation. It is from the connected phone that messages will be sent. The big advantage of the service is that it takes only a couple of minutes to launch and start working.
To connect your phone, use the QR code available when you click on your trial channel in your personal account. Then open WhatsApp on your mobile device, go to Settings -> Connected devices -> Connect device -> Scan QR code.
In the second and third steps, the service will ask you to customize the channel: write its name for your convenience, set webhooks, change settings. All these steps can be skipped, and we will come back to webhooks a little later. After launching, you will find in the center block under the information about limits, your API KEY, that is Token. This token will be used to authenticate your API requests. Generally, it's added to the request headers as a Bearer Token or simply as a request parameter, depending on the API method you're using.