How do I preview and test a WhatsApp transactional message?

Introduction

The Test tab is available as soon as the Content step is approved. This tab allows you to run a proof test to validate the message's appearance and the integration of personalization fields on smartphones before the campaign is published.

Sending a test

Since sending WhatsApp messages relies on the NMP API, it is recommended to test both the visual rendering and the data transmission.

• Send a test message on WhatsApp: Enter the test phone number(s) in international format (e.g., +33612345678) in the field Test Recipients, then click Send a Test. The message is sent instantly to the WhatsApp app on the target phone.

• Customization Management: If your template includes personalization fields (e.g., {rdv_date}}), you can set test values to verify the display:

  • Manual entry: Enter the desired value directly into the text fields dedicated to each variable.

  • JSON input: For more complex or technical scenarios, you can switch to JSON mode to inject the exact object that will be sent during actual API calls. This makes it easy to detect any formatting errors before going live.

  Note: The mobile preview in the center of the screen updates automatically based on the values you enter.

• Test an API call: It is also possible to run a test directly via the API using the information available in the API Guide (test endpoint URL, message code and cURL call example).

Conclusion

Once the tests have been validated on your mobile device, you can move on to step How to publish a WhatsApp campaign?.