“Best DNS to speed up the internet” is one of the searches that brings the most readers to this site, and it deserves an answer without hype. DNS speeds up one very specific thing, doesn’t speed up everything else, and in two minutes you can find out whether it will change anything for you.
What DNS doesn’t touch
When you download a file, watch a video or play online, data flows directly between your device and the server. DNS isn’t on that path: it stepped in once, at the start, to translate the name into an address, and then stepped aside. So switching resolver doesn’t change:
- Download or upload speed. A speed test gives the same figure before and after.
- Streaming quality: the resolution you get on Netflix or YouTube is decided by your bandwidth.
- Ping in games or delay in video calls, which depend on distance to the server and your network.
- How long a large download takes once it has started.
If anyone promises a DNS that “doubles your speed”, they’re selling something.
What does change
Before connecting to any server, your device has to ask the DNS for its name. That query takes 5 to 100 milliseconds depending on the resolver and your network, and a modern website doesn’t make one: it makes dozens, because it loads fonts, scripts, images and trackers from as many domains. Many of those queries chain up before the page draws.
That’s the difference you feel. With a resolver answering in 10 ms, a page with thirty domains loses a third of a second to DNS; with one answering in 80, nearly two and a half seconds. It doesn’t download faster, but it starts a good deal sooner, and that’s the feeling of speed while browsing.
There’s a second, cruder case: ISP resolvers that drop queries. Every lost query is a second or two of waiting until the system retries. In our measurement from Madrid, DNS.WATCH dropped 77% of queries and Comodo 42%; a DNS like that makes the internet feel broken even on a perfect connection.
How to tell whether it affects you
Don’t use a download speed test: it doesn’t measure this. Use the DNS speed test, which runs five rounds of queries against seven resolvers from your browser and ranks them by real latency.
- If the best ones answer under 20 or 30 ms and your connection is fine, DNS isn’t your bottleneck. Changing it will give you encryption or filtering, not speed.
- If the fastest answers in 10 ms and you’re using one that takes 80 or more (usually the ISP’s, though the test doesn’t include it), there’s a real improvement on every page.
- If any drops queries, avoid it however fast it is when it does answer.
From Madrid, with the answer cached, Cloudflare, Quad9, CleanBrowsing and DNS4EU answered in 5 or 6 ms and Google in 7; cold, forcing full resolution, between 22 and 35. From your ISP the order may differ, and the article on the fastest DNS by region explains why.
What genuinely speeds up the internet
While you’re at it, these are the things that move the speed needle, in order of effect:
- Cable instead of Wi-Fi for anything that doesn’t move: computer, TV, console.
- 5 GHz Wi-Fi and the router away from walls and microwaves.
- Fewer devices competing: the TV streaming 4K eats everyone’s bandwidth.
- A browser with an ad blocker: fewer domains to query and fewer scripts to run. A filtering DNS does part of that for every device.
- And DNS, for the specific case above.
In short
Changing DNS is free, takes two minutes and has no side effects if you pick an unfiltered resolver. If yours is slow or drops queries, the improvement shows on every page. If it’s already fast, it’ll give you other things (encryption, privacy, filtering) but not speed. Measure before expecting miracles: the test tells you, and the guides show how to change it on each system.