For $9.95 one time, you can purchase version 2 of GRC's famous DNS Benchmark, receive all future improvements for free, use it for the rest of your life, and support this and all of GRC's services and other freeware:

Buy DNS Benchmark

Click to purchase the hugely improved
v2 DNS Benchmark for $9.95 USD.

v2 is SIGNIFICANTLY improved

v1 of GRC's DNS Benchmark has been downloaded 9,744,498 times since its 2009 release, years ago. But v1 has grown old. So we spent a year creating v2 of the DNS Benchmark which will be maintained as a commercial product going forward.

Why v2?

Proper Resolver Ranking: v1's DNS resolver ranking is wrong for the modern Internet – v2 corrects this. v1 exclusively prioritizes resolver caching performance over all other (uncached) lookup performance. This made sense back in 2009 when most web pages were served by their own domains. But the Internet has diversified, with modern web pages served from scores of different remote domains requested by your browser. Therfore, the uncached lookup of new domains is at least as important as cached lookup, and all DNS queries should be considered and treated equally. v2 does this to deliver comparisons that are correct for today.

IPv6: The Internet's support for IPv6 (the replacement for IPv4) is advancing slowly, but all operating systems and networks now support IPv6. This means that benchmarking the performance of the Internet's IPv6 DNS servers has become important since that's what many systems are already using today and will be using tomorrow. v2 fully supports benchmarking IPv6 servers alongside IPv4 nameservers, and...

DoH & DoT: Traditional IPv4 & IPv6 are not encrypted; they offer no security and no privacy. But modern DNS can be encrypted to prevent your ISP or your employer from monitoring your DNS lookups to determine where you go on the Internet and which websites you access. It is known that ISPs sell this information about their own customers. (It's legal and in the “fine print.”) v2 fully supports benchmarking DoH (DNS over HTTPS) and DoT (DNS over TLS) resolvers. v2 can compare the performance of IPv4, IPv6, DoH & DoT DNS side-by-side. This allows you to choose which encrypted services respond fastest from your location.

Much More Accuracy: Today's Internet is much larger and much busier than the Internet of 2009. Packets move across many more routers and are delayed by much more buffering. This significantly increases reply-timing “jitter”. v2 compensates for this by testing every DNS resolver 5 times more — 250 query-sets instead of only 50 — by default. This can be changed to 1x, 5x, 10x, 20x, 50x or 100x. The result are more stable, repeatable and accurate resolver benchmarks and comparisons.

Updated and Larger Built-in Resolver List: v1 received an update after 10 years to add the Quad9 resolvers. v2 contains a fully updated and expanded built-in list of 126 IPv4 resolvers, 43 IPv6 resolvers, 81 DoH resolvers and 60 DoT resolvers. Additionally, the custom list builder quickly scans through 4,909 possibly-faster resolvers for inclusion into the most comprehensive DNS Benchmark ever.

v2 includes many new features that were original goals (like those above)
and many that occurred to us during its year-long development.
One of our favorite surprise features is...

Automatic Slow Resolver Sidelining: v2 doesn't waste time benchmarking resolvers that will never be able to compete. Any resolver loaded into the benchmark is given 10 opportunities to reply within a maximum time. (This defaults to a generous 50 milliseconds but can be changed by its user.) Resolvers that are never able to return a reply quickly are “sidelined” so that no time is wasted benchmarking them more thoroughly. The sidelining status of any resolver may also be toggled by its user.

Save Benchmark Results: v2 contains the same “Conclusions” tab which contributed to the popularity of v1. But v1 never had an option to save the benchmark's results as a simple file showing the resolver ranking, name and performance. v2 allows its results to be saved as either a simple space-padded text file or as a spreadsheet readable CSV (comma separated values) file.

Faster -and- Slower Operation: v2 allows its query-issuing speed to be changed because network speed differs and extra layers, such as VPNs, can require slower operation. v2 defaults to spacing resolver queries 20 milliseconds apart, but that may be changed in either direction for faster or slower operation.

Advanced “Jitter-Aware” Statistics: As noted above, the Internet has become a great deal more “jittery” as it has grown in size and complexity. v2 carefully determines and takes the certainty of its measurements into account.

Selectively Benchmark Specific Protocols: Even though v2 supports all DNS protocols, you might wish (for example) to focus only upon DoH to choose the best resolver for your browser's built-in DoH support. At benchmark time, when v2 sees differing protocols, it confirms that you wish to benchmark them all and offers to benchmark only one class of resolvers.

Individually Enable/Disable Protocols: Even though v2 supports IPv6 resolvers, many ISPs only offer IPv4 service. v2 allows you to individually enable or disable benchmarking for each class of resolver. You can disable IPv6 and it will remain disabled until you re-enable it.

Pin Resolvers to Top: By default, the resolvers your system is currently using are sorted by performance along with all other resolvers. But some users wish to keep an eye on their system's resolvers and not go scrolling to find them. v2 allows the system's resolvers and any individual resolvers to be “pinned” to the top of the resolver list.

DNSSEC domain signing verification: “DNS SECurity” allows DNS records to be cryptographically signed to prevent them from being altered or spoofed. Although it is not yet widely used, v2 supports the display of DNSSEC-aware resolvers by coloring them green. When DNSSEC becomes important, you and v2 will be ready.

Up to 500 Resolvers at Once: There's normally no need to simultaneously benchmark hundreds of resolvers at the same time. But if you wish to, v2 can handle up to 500.

Windows 10 & 11 Aware: v2 runs on Windows 7, 8, 10, 11 and beyond. (It also runs nicely on Linux under WINE.) Windows 10 & 11 added native shadows and screen scaling that confused v1 so we have fixed that for v2.

Benchmark progress monitor: As shown by the screenshot below, v2 displays the work completed and remaining in total queries, as a percentage and as time. The traditional progress bar is nice, but especially for longer runs it can be nice to see the numbers.

Nameserver Page Cloning: Any of the four Nameserver pages may be “cloned” to its own static snapshot freestanding window for comparison or record keeping.

And MANY More: v2 has many additional new features. It has many pop-up notifications to guide and assist its user by asking how many samples should be taken, which protocols should be used, how fast the benchmark should run, options to add missing system resolvers, reminders to save changed resolver lists, reminders when local resolvers are missing.

Owners of the $9.95 DNS Benchmark will never be asked to pay anything again. No subscription nonsense or future upgrade costs. When you buy it you own it for life, and your support of this software encourages its continuing development.

Buy DNS Benchmark

Click to purchase the hugely improved
v2 DNS Benchmark for $9.95 USD.

What about the v1 freeware?

Where's the original version 1 DNS Benchmark?

The DNS Benchmark documentation pages (below) are being updated to reflect the many improvements made to v2. Many of these pages will not align with v1's original operation and features.

GRC's DNS Benchmark Pages:

1 Version 2 DNS Benchmark     1 DNS Benchmark Introduction     2 Features & Operation Walkthrough     3 System Menu Options & Commands     4 Command-Line Operation Reference     5 Building a Custom Nameserver List     6 DNS Benchmark Resource Files     7 Configuring your DNS Nameservers     8 Benchmark Questions & Answers     9 DNS Benchmark Version History   10 Running GRC Apps under WINE   11 DNS Spoofability Test Introduction

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Last Edit: Dec 17, 2025 at 21:01 (52.80 days ago)

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