Secure Localhost Testing With UnderPass

A GUI application that helps you test locally hosted pages or privately hosted projects on 3000+ browsers for desktop and mobile.

live interactive browser testing tools

One Click Launch To Trigger LambdaTest Tunnel

No need to launch tunnel through CLI anymore. UnderPass will automatically execute the tunnel binary to establish a secure connection for testing locally hosted pages on LambdaTest.
Underpass Documentation

Test Websites with Private Certificate

Underpass enable MITM (Man-in-the-middle) for website with self signed certificates. You can now test locally hosted or privately hosted websites using self signed certificates on your own system or internal network.
live interactive browser testing tools
Test using Proxy

Localhost Testing Behind Proxy

Perform Localhost testing to test websites hosted behind proxies. You can define PROXY HOST, PROXY PORT, PROXY USER and PROXY PASSWORD for your remote server, office network or even a local machine.

Detailed Verbose Logs

Found an error while you launched the tunnel through UnderPass? Enable Verbose and get detailed logs for your LambdaTest Tunnel and troubleshoot any technical errors.
Detailed Verbose Logs
Test Using Shared Tunnel

Test Using Shared Tunnel

No need to create separate instances for individual users for a single project. You can create a shared tunnel for the team and users can launch it using UnderPass in a single click.

Select Connection Modes

UnderPass by default auto detects the best possible connection modeto ensure best testing speeds possible. Depending on external envrionments like network, Underpass optimizes the connection for the best transfer speeds and best testing experience.
Select Connection Modes

More Reasons To Love Underpass

A dedicated desktop application with features that will make your local testing experience smoother and help you ship products faster.

Integrated developer tools

Set Advance Configurations

Find Detailed Logs for your LambdaTest Tunnel using advanced configurations.
automated browser testing tools to test locally hosted websites

Easy Access To Local Directory

Select or change the local file path directly from the UnderPass app with a single click.
Geolocation Testing

Select Your Environment

Test your web pages or apps on local environment with faster & deploy quality builds using UnderPass.
24/7 Support Chatbox

24/7 Support From Our Tech Experts

Our tech experts are available on our support 24*7. You can get in touch with us by filling up the contact form, messaging in-app, or through call. You can also write to us at .
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