How to Read the Data Columns in Public DNS Server List

The Public DNS Server List table has six columns: IP, ASN, Country, City, Reliability, and Speed. Each row describes one public DNS server that is reachable over IPv4 or IPv6. The list spans more than 160 countries and is continuously monitored to confirm servers stay online and responsive. Reading the columns correctly lets you compare servers on location, operator, and measured performance instead of guessing from the IP alone.

IP

The IP column holds the server's address. It can be an IPv4 address such as 172.64.36.255 or an IPv6 address such as 2610:a1:1018::5. This is the value you enter when configuring a DNS resolver on a device or router.

• IPv4 addresses are the four-number form and are the most widely compatible.
• IPv6 addresses are longer and use colons; they only work if your network and device support IPv6.
• A single provider can appear multiple times with different IPs, as Cloudflare does with 172.64.36.255 and 172.64.47.147.

ASN

ASN stands for Autonomous System Number. It identifies the network that owns or announces the IP address, usually together with the organization name. Examples from the list include AS13335 Cloudflare, Inc. and AS16276 OVH SAS.

• The ASN tells you who actually operates the server, which may differ from the country shown.
• The same organization can appear under several ASNs across different regions.
• ASN is useful for spotting servers that belong to the same provider even when their IPs look unrelated.

Country and City

These two columns give the server's geographic location.

• Country is the nation where the server is registered or located, such as United States, Russia, or Japan.
• City narrows it further, for example Chicago, New York, or St Petersburg.
• Location matters for latency: a server physically closer to you usually responds faster, though routing and peering can change that.

Reliability

Reliability is a percentage showing how consistently the server responded during monitoring. Higher is better.

• 98.44 % (Selectel, St Petersburg) and 97.22 % (Whiz to Coho, Hillsboro) indicate very stable servers.
• Values in the 50–60 % range, such as 52.93 % for a Cloudflare entry, mean the server was reachable only about half the time during checks.
• Treat this as a stability signal, not a guarantee of future uptime.

Speed

Speed is reported in milliseconds (ms) and reflects measured response time. Lower is better.

• 5 ms and 5.5 ms entries are extremely fast.
• 28 ms to 61.5 ms is typical for well-connected servers.
• Very high values such as 1208.5 ms or 1380.75 ms indicate slow responses and are usually poor choices.

Putting the Columns Together

Use the columns as a combined filter rather than judging any single one:

1. Pick servers in a country or city near you to keep latency low.
2. Check Reliability to avoid servers that frequently drop offline.
3. Compare Speed in milliseconds and prefer the lower numbers.
4. Use ASN to confirm which organization runs the server if that matters to you.

For example, a row with 98.44 % reliability and 91.22 ms speed is a stronger candidate than one with 52.93 % reliability, even if both are in the same country.