What Is ngrok? How It Works and How to Use It

Ngrok is a reverse proxy tool that allows developers to expose their local apps, APIs, or webhook endpoints to a public URL without deploying or modifying network settings, making it particularly useful for receiving webhooks, sharing work-in-progress builds, and testing integrations that require a real HTTPS URL. It operates by running a local agent that creates an encrypted outbound connection to ngrok's cloud, assigning a public URL for the local service without needing firewall adjustments, and providing a local web interface for request inspection. While ngrok is safe and encrypted, users must manage the security of their tunnels by avoiding exposure of sensitive data and terminating sessions when not in use. Although the tool offers a free tier with limitations on usage and features, paid plans provide increased capabilities, such as custom domains and team collaboration. Ngrok is optimal for quick sharing and debugging, but for automated testing across multiple browsers and devices, a testing-cloud tunnel like TestMu AI Underpass is recommended, as it maintains privacy and facilitates extensive cross-platform testing.