How to Check for DNS Leaks on Mac and iOS: A Step-By-Step Guide (Don't Skip This!)

Over the past two years, DNS leak issues have been mentioned by more and more people. Many users clearly have a proxy enabled, yet platforms are still able to identify their real location. In most cases, this is closely related to DNS leaks.

This is especially common among users of macOS or iOS devices. The system settings may look clean and network access works normally, but DNS requests quietly go through the local network, without the user noticing at all.

In this article, based on my own hands-on experience with macOS and iOS devices, I’ll walk you through the complete process of DNS leak detection, common pitfalls, and how to properly prevent DNS leaks afterward.

I. What Is a DNS Leak? Why macOS and iOS Users Are More Likely to Miss It

DNS is like the “phonebook of the internet.” When you visit a website, the system first queries a DNS server to find the corresponding IP address.

A DNS leak means that even though you are using a proxy or IP tool, DNS requests are still being sent through your local or ISP DNS servers.

As a result, even if your IP appears to be overseas, DNS information still exposes your real location. Platforms can easily detect abnormal environments through comprehensive analysis.

macOS and iOS users are more prone to this issue mainly because:

•  The system’s default DNS has high priority

•  Safari and Chrome enable DoH (encrypted DNS) in certain versions

•  Some proxy tools do not fully take over DNS requests

II. The Correct Steps for DNS Leak Detection on macOS / iOS

1️⃣ Connect Your Proxy or IP Tool Properly (Prerequisite)

Make sure that:

•  The network is successfully connected

•  The IP address has switched to the target region

•  Multiple proxy tools are not enabled at the same time

It’s recommended to restart your browser or network connection before testing to avoid cache interference.

2️⃣ Use a Professional DNS Leak Detection Tool

Method 1: DNS Leak Detection Platforms

Typical steps include:

•  Open a DNS leak test page

•  Click “Standard Test” or “Extended Test”

•  Check the returned DNS server list

Focus on two key points:

•  The country/region of the DNS servers

•  Whether local ISP names appear

If you see entries like “China Telecom / China Unicom”, it basically confirms a DNS leak.

Method 2: Check Together with Browser Fingerprint Detection (Highly Recommended)

In many cases, DNS leaks are not exposed alone but are identified by platforms together with browser fingerprint data.

This is when you can use the ToDetect Fingerprint Checker:

•  Verify whether DNS and IP are consistent

•  Check WebRTC, timezone, language, and system information

•  Assess whether the overall environment is “clean”

If the DNS region does not match the IP or timezone, the risk level increases significantly.

III. Common DNS Leak Scenarios on macOS / iOS

The following situations are pitfalls that most people have encountered:

•  Only changing the IP and ignoring DNS

•  Direct access using Safari’s default settings

•  DNS being overwritten after using public Wi-Fi on iOS

•  Secure DNS (DoH) enabled in Chrome

•  Proxy tools without “DNS takeover” enabled

Especially on iOS, even if you manually change DNS settings, the system may automatically revert to default after network switching.

IV. Practical Tips for Preventing DNS Leaks on macOS / iOS

Method 1: Use Proxy Tools That Support DNS Takeover

When choosing a proxy or IP tool, make sure it supports at least the following:

•  Custom DNS configuration

•  Forced use of remote DNS

•  Ability to disable WebRTC

This is the most hassle-free solution for DNS leak prevention.

Method 2: Manually Set Secure DNS (Advanced)

macOS users can go to: System Settings → Network → Current Network → DNS

Manually add trusted overseas DNS servers, such as:

•  1.1.1.1

•  8.8.8.8

iOS users can modify DNS settings in the Wi-Fi details page (be sure to select “Manual”).

Note: Manual DNS settings are only a supplement and cannot 100% prevent leaks; they must still be used together with a proxy.

Method 3: Test Together with Browser Fingerprint Environments

DNS leak prevention is not an isolated issue. After setting up an environment, it’s recommended to:

•  Run a DNS leak test

•  Use the ToDetect Fingerprint Checker to review the full fingerprint

•  Ensure IP, DNS, timezone, and language are logically consistent

This is a step many experienced users perform routinely.

Final Thoughts: DNS Leak Detection Must Be Viewed from Multiple Dimensions

DNS leak detection is not a one-time task, but a detail that needs repeated verification.

Especially on macOS and iOS, system updates, network changes, and browser version updates can all reintroduce vulnerabilities into an otherwise secure setup.

It’s recommended to perform DNS leak detection together with browser fingerprint detection. Each time an environment is set up, run the ToDetect Fingerprint Checker once to confirm that IP, DNS, timezone, and language are logically consistent before officially using the environment. Hopefully, this guide helps you avoid unnecessary detours.