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Could not detect your DNS resolver Trying to detect your DNS resolver
You are using a DNS resolver on {{resolverorg}}. {{bestguess}}.
How was this detected?

Your DNS performance, right now

How fast can you get a response from your DNS resolver and from the major authoritative DNS providers through your resolver? Is this good or not so good compared to other users in your country?
No benchmark data available :(
Find out which resolver gives you best performance. Try dnsperfbench now!
Your DNS performance is good.
Maybe it can be even better with a different resolver? Try dnsperfbench now!
Your DNS performance is not good.
Find out which resolver gives you best performance. Try dnsperfbench now!
Running tests
Could not run performance tests. Why not?
Benchmark RTT
{{}} {{benchmark[cluster.rumid].median|number:'0'}} {{dnsrum_results[cluster.rumid]|number:'0'}} FAIL

Get a faster Internet: speed up your DNS!

Can you get better DNS performance with a different resolver?
Use our free, open-source DNS Performance Benchmarker tool (Linux, Mac and Windows) to find out which resolver gives you the most reliable and fastest Internet experience.

  • Benchmark your current resolver against all major public resolvers
  • Measure cache hit and cache miss performance !
  • Runs multiple tests to ensure statistical significance
  • View results per resolver and a summary

Global DNS Resolver Performance Benchmark

How fast and reliable are the popular open DNS resolvers around the globe?

Every 15 minutes, we run a test on all TurboBytes Pulse agents (>50 locations, most in people's homes).
The table below summarizes the test results of the last 24 hours, showing response times in milliseconds or % of tests that failed (Fail ratio).
= 2 or more tests failed from a single location

{{alldata.resolver_names[key]}} {{key}}
{{}} {{agent.asn}} {{getms(agent.statistics[key][metric])}} {{agent.statistics[key][metric]*100|number:0}}%

View the results of each DNS performance test run (oldest at top, newest at bottom).

{{item.timestamp|date:"yyyy-MM-dd, HH:mm:ss"}} {{item.test_id}}


Find the answers to common questions here.
Missing something or have feedback? Let us know on Twitter at @ismydnsfast


What is IsMyDNSFast?

IsMyDNSFast? helps Internet users understand the differences in performance between various DNS resolvers. Additionally, IsMyDNSFast? provides insight into global DNS resolver performance based on fresh data collected from machines connected to consumer ISP networks.

Who runs the IsMyDNSFast? website?

IsMyDNSFast? is operated by TurboBytes, a provider of Multi-CDN services.

Why did you build this site?

We built IsMyDNSFast? because we have a strong interest in Internet performance in general and specifically in DNS performance. DNS is at the heart of our Multi-CDN platform and we've been collecting data on the real-world performance of authoritative DNS providers for a few years.

The launch of Cloudflare's on April 1 2018 (nice move @eastdakota) created a lot of buzz on Twitter. People raved about the low response times and the public benchmark of has since shown is the fastest public DNS resolver from many (datacenter) locations. On the flip side, suffered from severe reachability issues.

Many questions came to mind. Is reachable from my home? If so, is Cloudflare's resolver much faster than other resolvers? And what about cache miss performance (client <> resolver <> authoritative)?

These questions sparked a few ideas, the first one being a command line tool to easily compare cache hit and cache miss performance of various resolvers. dnsperfbench was born.

Not long after we discussed the idea to run our own global dns resolver perf benchmark using TurboBytes Pulse, because most Pulse agents are in people's homes and aren't consumers the primary audience of DNS resolvers? Yes!
The tool and the Pulse powered benchmark come together on

How do you detect my current DNS resolver?

JavaScript code on this site does a request for <random> The response contains your machine's IP address and the IP address of the resolver machine that sent a query to our nameserver.

Next, the code queries the API of to know which network (ASN) both IP addresses belong too. For example, if the resolver IP belongs to AS36692 we know you are using the OpenDNS resolver. If the client IP network and resolver IP network are the same, we know you are using your ISP provided DNS resolver.

Shoutout to Ben of for providing a great service. Thanks @ipinfoio, keep up the good work!

What is dnsperfbench?

dnsperfbench is a command line tool to compare performance of DNS resolvers. By default, dnsperfbench runs tests against Google Public DNS, OpenDNS, Cloudflare's, Quad9, Norton, Comodo and Clean Browsing.

You may optionally specify IP addresses of additional resolvers to include in the benchmark, for example the IP address of your ISP's resolver.

For each resolver, dnsperfbench first runs runs a few tests for a specific FQDN, to ensure the resolver has the response in cache. Next, dnsperfbench runs 15 cache hit tests (we call this ResolverHit) and 15 cache miss tests against several major authoritative DNS providers.

Once done, the tool shows the results per resolver (median and mean RTT and % tests that failed) and computes an overall performance score per resolver. The lower the score, the better was the resolver's performance.

It's easy to download & run dnsperfbench. Try it !

Why is dnsperfbench a great tool?

  1. Measures not just cache hit performance but also cache miss performance
  2. Runs multiple tests to ensure statistical significance
  3. Free and open-source with a 'do whatever you want with it' license

How do I use dnsperfbench?

dnsperfbench runs on the command line, without arguments or with one+ optional arguments. View the information about the arguments on Github.

Where can I download dnsperfbench?

The source code is on Github. You may compile dnsperfbench from source, run from Docker or download the latest release (Linux, Mac, Windows).

Is the source code open, free to use and on Github?

Yes, the code is on Github and has the MIT license.

How do 'Your DNS performance, right now' tests work?

TurboBytes monitors performance of recursive and authoritative DNS using real user measurements (RUM), using JavaScript code executing in the browser. This code executes on this website when the page loads, and the results are presented on screen. The Introducing RUM for DNS article on the TurboBytes blog provides a thorough explanation of how our RUM for DNS works.

What is the benchmark data?

The benchmark data consists of the median response time of each DNS endpoint based on measurement data collected from other users' browsers in the past 24 hours. When this page loads, the browser requests the benchmark data from our server. From this request we see your IP address and the server returns the benchmark data based on measurements from other users in the same country / on the same network.

How is the big Yes or No computed?

The page computes a performance score based on the tests that ran in your browser ("Now"): multiply the ResolverHit response time by 5 (to give it a higher weight), add up all response times and add 1000 ms for a failed test.

The page also computes a performance score based on the benchmark data ("Benchmark"): compute the sum of the median value of all endpoints, where the ResolverHit median response time is multiplied by 5.

If the Now score is lower than the Benchmark score, the page shows a big green Yes! or else a big red No.

Why did the performance tests fail to run?

RUM for DNS tests don't run if Do Not Track is set. The tests run only in modern Chrome, Opera and Safari browsers and in Firefox 60+ but not in IE and Edge browsers.

Load this site in a different browser if you're curious to see the RUM for DNS results for you.

What is ResolverHit?

The ResolverHit test involves the client sending a query to the resolver for This record has a one day TTL and we use it in our RUM for DNS monitoring so most resolvers should serve the response from cache.

Why is ResolverHit data sometimes missing?

Our JavaScript code on this page fetches an object from and gets the DNS Lookup Time from the browser's Resource Timing API. If the DNS Lookup Time is below 4 milliseconds, we know the response came from browser/OS/router cache or it came from a resolver cache that is very close by (aka: datacenter). In both cases, we label the DNS Lookup Time as invalid and don't show it on this page.

What is NS1-Route53?

More and more companies use two DNS providers for their domains, including Etsy, Linkedin and eBay. In case one of the DNS providers is performing badly (DDoS, ...), many recursive resolvers will quickly figure out the other provider is better and send queries to that other provider. This is called SRTT. Many resolvers do SRTT and you can read more about it on the TurboBytes blog at Why You Should Use Two DNS Providers.

TurboBytes uses NS1 and AWS Route53 as the primary DNS providers in its Multi-CDN platform, and logically we track the performance of not just each provider but also of the combo.

Will you add more authoritative DNS providers?

We expect to add a few more in the future. We welcome all global DNS providers to participate, the more the better!

Why did you build yet another resolver performance benchmark?

We believe a DNS resolver performance benchmark should run from people's homes, not datacenters, and because most of our TurboBytes Pulse agents are in homes it was an easy decision to build the IsMyDNSFast? website.

The second reason to build this site and the dnsperfbench tool is provide users insight into both cache hit and cache miss performance of DNS resolvers. Probably most queries to resolvers are a cache hit, but cache miss performance is important nevertheless.

How is your benchmark different from

dnsperf runs their tests from more locations (~200), but these are all/mostly datacenters. The main audience of public DNS resolvers is consumers and these people don't live in datacenters, right?. IsMyDNSFast? tests using >50 Pulse agents and by far most of these are in people's homes.

Can I see weekly or monthly data?

No, but maybe in the future.