DNS Benchmark: How to Test and Choose the Fastest DNS
DNS Benchmark is a benchmark utility which is developed to analyze open DNS servers’ speed and other response-time related parameters to let you decide which DNS server should be used. According to the developer, it is built to check “How fast and reliable your ISP’s DNS server is, when compared to other open DNS servers”? It conducts several tests and generates a detailed report, which lets you do DNS server reliability and speed comparisons.
Compatibility note: The tool is portable (no install), tiny, and works on all modern Windows versions (including Windows 10/11). It can also run on macOS/Linux via WINE. See the developer page for details: GRC DNS Benchmark.
Under the Nameserver tab, it lists a multitude of public DNS resolvers alongside your ISP-provided DNS. To start off with checking the fastest response, enable Sort Fastest First (left sidebar) and click Run Benchmark to conduct a test. It may take some time to check all the listed DNS servers’ response times.
After the test is finished, click any DNS name in the list to see a breakdown of response-time parameters. You’ll see three core measures:
- Cached – lookups served from a resolver’s cache.
- Uncached – fresh lookups that must be resolved on the internet.
- DotCom – resolver performance when going to the authoritative
.comnameservers.
There are four tabs—Name, Owner, Status, and Response Time—to view all the information about each server’s behavior.
Under Response Time, DNS Benchmark plots histograms for each parameter so you can visually compare consistency and latency.
The right-click context menu presents useful options to filter and manage the list. You can remove dead/slow DNS servers, copy an address to the clipboard, sort by different metrics, set graph scale, save the list as an image, and more.
Modern Tips for Accurate Results
- Build a custom list: After an initial run, use System ► Build Custom Nameserver List to scan a large global catalog and create a “fastest 50” tailored to your location. This gives more relevant results than the default starter list.
- Account for DoH/DoT & browser DNS: Many browsers can send DNS over HTTPS/TLS and may ignore your system resolver. Temporarily disable browser DoH/secure DNS while testing, or test from apps that use the system DNS, so you’re benchmarking what your OS will actually use.
- Test at different times: Congestion varies by time of day. Run multiple benches (morning/evening) and prefer servers that are both fast and consistent.
- Favor reliability & policy, not just speed: Popular choices include Cloudflare (1.1.1.1), Google Public DNS (8.8.8.8), and Quad9 (9.9.9.9). Quad9 additionally blocks known malicious domains by default; Cloudflare emphasizes privacy; Google offers broad anycast reach. Choose by your needs (speed, security blocking, privacy posture).
- Windows 11 & multiple interfaces: If your PC uses both Ethernet and Wi-Fi, confirm which adapter’s DNS you’re tuning, and repeat benchmarks if you switch networks.
Who Is It For?
A useful tool to analyze DNS server response time and compare your ISP’s provided DNS servers with public resolvers on the internet. Power users can validate stability and consistency; casual users can follow the Sort Fastest First plus Build Custom List flow to pick a sensible default.
DNS Benchmark supports all current versions of Windows, and also works under WINE on macOS/Linux for quick tests.
What’s New in This Update
- Added Windows 10/11 and WINE compatibility notes, with a link to the developer page.
- Included guidance on browser DoH/DoT and how it can bypass system DNS (affects benchmarking accuracy).
- Recommended building a custom nameserver list for location-relevant results.
- Provided up-to-date examples of reputable public DNS providers with links (Cloudflare, Google, Quad9) and what differentiates them.
- Light edits for clarity; preserved original structure and intent.
Last updated: October 15, 2025
Have you guys ever covered Steve Gibson’s other apps? He is the creator of such fine tools as SpinRite which is basically the only option when wanting a low-level data recovery tool. Really the best, saved my ass more than I care to admit.