Use DNS to Fix a Web Page Not Loading in Your Browser

Learn how to test and change your DNS configuration

A man in a server rack

PhotoAlto/Frederic Cirou / Getty Images

There are many reasons why a web page may not load successfully in your browser. Sometimes the problem is one of compatibility, such as occurs when a website’s developers use proprietary coding techniques that not every browser knows how to interpret. You can check for this type of issue by using a different browser to visit the website in question. That’s one of the reasons why it's a good idea to keep SafariFirefox, and Chrome web browsers handy. If a page loads in one browser but not another, you know it’s a compatibility problem.

One of the most likely causes of a web page not loading is a wrongly configured or poorly maintained DNS (Domain Name Server) system by your ISP (Internet Service Provider). Most internet users have the DNS system assigned to them by their ISP. Sometimes, this is done automatically; sometimes, an ISP gives you the DNS server’s internet address to manually enter into your Mac’s network settings. In either case, the problem is usually at the ISP’s end of the connection.

DNS is a system that makes it possible for users to use easily remembered names for websites and other internet services, rather than the harder-to-remember numeric IP addresses assigned to websites. For example, it is a lot easier to remember www.lifewire.com than 207.241.148.80, which is one of Lifewire.com’s IP addresses. If the DNS system is having problems translating www.lifewire.com to the correct IP address, then the website won’t load. You may see an error message or only part of the website may display.

That doesn’t mean there is nothing you can do. You can confirm whether your ISP’s DNS system is working correctly. If it isn’t, or even if it is, you can change your DNS settings to use a more robust server than the one your ISP recommends.

Testing Your DNS

Mac OS offers various ways to test and confirm whether an operational DNS system is available to you. Here's one of those methods:

  1. Launch Terminal, located at /Applications/Utilities/.

  2. Type or copy and paste the following command into the Terminal window.

    host www.lifewire.com
  3. Press the return or enter key after you enter the line above.

If your ISP’s DNS system is working, you should see the following two lines returned in the Terminal application:

www.lifewire.com is an alias for dynwwwonly.lifewire.com.​dynwwwonly.lifewire.com has address 208.185.127.122​

What is important is the second line, which verifies that the DNS system was able to translate the website’s name into an actual numeric internet address, in this case, 208.185.127.122. (The IP address you see may be different, but it will be in the same or similar format).

Try the host command if you’re having problems accessing a website. Don’t worry about the number of lines of text that are returned; it varies from website to website. What’s important is that you do not see a line that says:

Host your.website.name not found

If you see a website not found result, and you’re sure you entered the website’s name correctly and that there really is a website by that name, then you can be reasonably sure that, at least for the moment, your ISP’s DNS system is having problems.

Use a Different DNS

The easiest way to fix an ISP’s malfunctioning DNS is to substitute a different DNS for the one provided. One excellent DNS system is run by a company called OpenDNS (now part of Cisco), which offers free use of its DNS system. OpenDNS provides complete instructions for making the changes to Mac’s network setting, but if you’re having DNS issues, you may not be able to access the OpenDNS website. Here is the quick scoop on how to make the changes yourself.

  1. Launch System Preferences by clicking on the System Preferences icon in the Dock, or choosing the System Preferences item from the Apple menu.

    Screen shot of Mac System Preferences window
    Mac System Preferences.  Coyote Moon, Inc.
  2. Click the Network icon in the System Preferences window.

  3. Select the connection you are using for internet access. For almost everyone, this is Wi-Fi or Built-In Ethernet.

    Screen shot of System Preferences Network screen
    System Preferences Network screen.  Coyote Moon, Inc. 
  4. Click the Advanced button.

  5. Select the DNS tab.

    Screen shot of Network_DNS tab
    Network DNS tab.  Coyote Moon, Inc.
  6. Click the plus (+) button below the DNS Servers field and enter the following DNS address:

    208.67.222.222

  7. Repeat the above steps and enter a second DNS address, shown below:

    208.67.220.220

  8. Click the OK button.

  9. Click the Apply button.

  10. Close the Network preferences pane.

Your Mac now has access to the DNS services provided by OpenDNS, and the wayward website should now load properly.

This method of adding the OpenDNS entries keeps your original DNS values. If you want, you can reorder the list, moving the new entries to the top of the list. The DNS search starts with the first DNS server in the list. If the site is not found in the first entry, the DNS lookup calls on the second entry. This continues until the lookup is made or all the DNS servers in the list have been exhausted.

If the new DNS servers you added are performing better then your original ones, move the new entries to the top of the list by selecting and dragging it to the top.