A Practical Guide to Preventing DNS Leaks: Step-by-Step Configuration

DNS leaks have become an important indicator affecting anonymity and privacy security. You may have installed an IP tool or configured a proxy and feel that you can stay invisible on the internet.

But as long as DNS is still exposed, every website you visit, every redirect you make, and even your real network environment can be easily tracked.

Next, I will explain how to completely fix DNS leaks, along with a detailed hands-on DNS leak protection configuration guide.

1. What is a DNS leak? Why is it so dangerous?

DNS (Domain Name System) is essentially the “address book of the internet.” When you open a website, the browser first uses DNS to look up the real IP address of the server.

If your system, browser, or apps still use the local DNS server for resolution, then even if you're connected to an IP tool, your “websites visited” will be exposed to your ISP or other third parties.

Especially now, many detection websites combine browser fingerprinting + DNS leak testing. Once DNS is exposed, your overall anonymity drops instantly.

2. How to perform DNS Leak Tests?

1. Online DNS Leak Tests

Using professional detection sites, they can quickly analyze where your DNS queries originate. If they still point to your local ISP, then a leak exists.

Here we recommend a more comprehensive tool: ToDetect Fingerprint Detection Tool (integrates “DNS Leak Test + Fingerprint Identification + WebRTC Check”).

It can check DNS leaks + browser fingerprinting in one run, detecting DNS leaks, WebRTC leaks, Canvas fingerprints, system fingerprints, and other identifiers.

Tools like this simulate real browsing environments, so the results match your actual exposure level more accurately.

2. System-level / Terminal-level Testing

For Linux, macOS, and Windows, you can use terminal commands to check whether DNS queries go through the proxy tunnel and confirm whether DNS servers match your intended configuration.

3. Practical Solutions to Completely Fix DNS Leaks (Most Important)

Solution A: Change DNS at the System Level (Basic but Necessary)

On Windows: Open “Network and Sharing Center” → Click your current network → “Properties” → Check IPv4 → “Properties”

Set DNS, for example:

• 1.1.1.1 / 1.0.0.1 (Cloudflare)

• 8.8.8.8 / 8.8.4.4 (Google)

• Or use DNS-over-HTTPS (DoH)

Note: Changing DNS alone cannot fully prevent leaks—it is only the first step.

Solution B: Force DNS Proxying in IP Tools or Proxies (Most Effective)

Whether you use Clash, V2Ray, Trojan, OpenVPN, or WireGuard, you must enable options like “Force DNS Proxy” or “Fake-IP”.

1. V2Ray / XRay

We recommend using a dokodemo-door inbound to intercept port 53:

This ensures your system’s DNS requests are fully intercepted by the proxy.

2. WireGuard

In the [Interface] block, add: DNS = 1.1.1.1

Also ensure AllowedIPs contains all traffic: 0.0.0.0/0

Otherwise DNS queries will bypass the tunnel.

Solution C: Browser-level DNS Leak Prevention (Often Overlooked)

Chrome / Edge / Brave

Path: Settings → Privacy & Security → Secure DNS → Enable Secure DNS. Recommended: Cloudflare or custom DoH provider.

Firefox: Comes with DNS-over-HTTPS built-in. Path: Settings → Privacy & Security → Enable DoH

Special reminder: For maximum privacy, disable WebRTC to avoid local IP leaks.

Solution D: Verify with Fingerprint Detection Tools (Mandatory)

After configuring everything, you must run tests again—otherwise you may only “think” it works.

Use the ToDetect Fingerprint Detection Tool, which not only detects DNS leaks but also:

Canvas fingerprints, WebGL fingerprints, font fingerprints, browser fingerprint correlation, IP leaks, WebRTC leaks

You can clearly see whether your DNS protection truly works. This is often overlooked: Configuring without verifying is just self-deception.

Summary: Three Layers of Protection to Fully Stop DNS Leaks

Completely fixing DNS leaks is not done by adjusting a single setting. It requires a combination: Encrypted system DNS, Proxy takeover of DNS, Browser leak blocking, and final verification using professional tools.

As long as you follow the steps above and use the ToDetect Fingerprint Detection Tool to test DNS leaks and browser fingerprints, you can effectively plug most information leak points.