How to Test if Your Proxy is Leaking DNS: 2026 Setup Guide

You configured a proxy. Traffic is routing through it. IP check passes. Job done?

Not necessarily.

DNS leaks are one of the most common ways a proxy setup can expose your real location and ISP while appearing to work correctly. Your IP changes, but your DNS queries still go home.

This guide covers:

What a DNS leak actually is at the network level

How to detect one reliably

How to fix it across different proxy configurations

Programmatic detection methods with code examples

What Is a DNS Leak?

When you type a domain into your browser, a DNS resolver translates it into an IP address.

Normally this happens through your ISP's DNS server.…