How do DNS settings affect your internet speed so much?


You may have heard people tell you to change your DNS if your internet speed suffers. Some may even claim that changing DNS settings can actually double your internet speeds!


Your DNS settings play an incredibly important role in your browsing speeds. You regularly use DNS, even if you don’t know it. So let’s discuss what DNS is and why your DNS settings affect your internet speeds.


What is a DNS server?

DNS is a simple acronym for Domain Name System. Think of it as a huge directory that stores all the addresses on the Internet. When you enter a URL into your browser, it is translated into an IP address by your browser using DNS records.

Each device connected to the Internet has its own IP address. Without DNS servers, you would have to remember every IP address to access a specific website. But, luckily, with DNS records, the hostname is automatically translated to an IP address, and your browser sends a request to the server, which returns the resources that load your site.

There are both dynamic DNS servers and static DNS servers. The former regularly update DNS records as IP addresses change. There are several free dynamic DNS providers that you can also use.

How Your DNS Server Affects Speeds

To understand how your DNS server affects speeds, it’s important to focus on DNS records, the most important of which is the A record, which stands for “address.”

The A record maps all domain names to IP addresses. When you access a website, DNS resolves your query, translates the URL to an IP address, and then points to a server where the website is hosted.

If latency is high on a DNS server, it can slow down the website name resolution process. This may cause the website to load slower than expected.

By default, the DNS server is selected automatically, although some ISPs may use a specific DNS server geographically close to the user.

But, if the DNS servers are under a heavy traffic load, it will cause name resolution times to spike, thereby slowing down browsing performance. Likewise, if the DNS server is located a considerable distance from where you live, it will take longer to resolve queries on the website.

You can change your DNS settings to improve your internet speeds, but it’s never a one-size-fits-all solution. Ideally, you’ll want to choose a DNS server closer to you that has up-to-date records.

Websites on the Internet are distributed across servers or nodes. Many use a Content Delivery Network (CDN) such as Cloudflare or Google DNS to improve performance and load their sites faster.

Core files are distributed across the network, rather than being stored on the same server. This reduces latency and improves your website loading time.

For example, let’s say you’re based in Canada and you upload a file through a website that uses Cloudflare. If the outdated DNS A records resolve the query to a Canadian server, your speeds will be pretty good.

However, if DNS resolves your query to a server in the UK, for example, you’ll notice connection speeds slow down. Keep in mind that DNS queries generally don’t affect download speeds, but they do make websites load slower.

How to find the best DNS server

One of the best ways to find the fastest DNS server is to use Namebench. This is a simple utility tool designed by Google that allows you to quickly identify the tested DNS servers closest to your location. Here’s how it works:

1. Download and install Namebench

Once you’ve downloaded and installed Namebench, you’ll need to add the DNS server you’re using. In most cases, Namebench will automatically detect the nameservers you are using and populate them, as shown above.

It is a portable executable, so there is no need to install anything. Just download the app, extract it and it will run immediately.

2. Run the benchmark

Once you have run the benchmark, Namebench will show you the results. These results, shown below, can be a bit tricky to interpret, but ideally you just want to pay attention to the recommendations at the top. Here’s what it looks like:

If you look at the top, it indicates that the current primary DNS is the fastest, which means there is no reason to change things. You can also see the recommended configuration on the right, including primary, secondary, and tertiary server.

Next, Namebench shows you all of the DNS servers it has tested, along with the results for each. You can even see average response time and other technical details if you scroll down.

3. Change your DNS servers (if necessary)

Now, if you are connected to a slower DNS server, you can change DNS server in Windows 11 or macOS. There are several other ways to change your DNS settings also on Windows 11.

Keep in mind that you will need to change the DNS server for all connected devices. So, for example, if you’re connected to the internet using another device, like a PlayStation 5, you might also want to change the DNS.

Why DNS Servers Affect Your Internet Speeds

Arguably the most important factor is DNS lookup times, which is when your DNS resolves your query. The slower it is, the longer your website will take to load. Also, if the DNS cache was recently flushed, caching new records may take time.

DNS will check browser cache, OS cache and even send a query to the recursive DNS server (which is provided by your ISP) to resolve the query.

The Bottom Line: Should You Change Your DNS Settings?

It’s important to note that changing your DNS settings won’t always be necessary, as your ISP will usually connect you to the best performing DNS server.

But if you are traveling or connected to a DNS server that is not updated or is far away, you may experience slower speeds. Changing DNS settings will definitely help. In some cases, using a Smart DNS can also help.

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