Experimental Features

Experimental features can change; don't depend on them.

Determining Your External IP Address via DNS Lookup

You can use sslip.io's DNS servers (ns.nip.io) to determine your public IP address by querying the TXT record of ip.nip.io:

dig @ns.nip.io txt ip.nip.io +short    # sample reply "2607:fb90:464:ae1e:ed60:29c:884c:4b52"
dig @ns.nip.io txt ip.nip.io +short -4 # forces IPv4 lookup; sample reply "172.58.35.231"
dig @ns.nip.io txt ip.nip.io +short -6 # forces IPv6 lookup; sample reply "2607:fb90:464:ae1e:ed60:29c:884c:4b52"

This feature was inspired by Google's DNS lookup, i.e. dig txt o-o.myaddr.l.google.com @8.8.8.8 +short. There are also popular HTTP-based services for determining your public IP address:

A big advantage of using DNS queries instead of HTTP queries is bandwidth: querying ns.nip.io requires a mere 594 bytes spread over 2 packets; Querying https://icanhazip.com/ requires 8692 bytes spread out over 34 packets—over 14 times as much! Admittedly bandwidth usage is a bigger concern for the one hosting the service than the one using the service.

Determining The Server Version of Software

You can determine the server version of the nip.io software by querying the TXT record of version.status.nip.io:
dig @ns-ovh.nip.io version.status.nip.io txt +short
  "5.0.0"
  "2025/08/30-19:52:37-0700"
  "afb37dd"

The first number, ("4.1.0"), is the version of the nip.io DNS software, and is most relevant. The other two numbers are the date compiled and the most recent git hash, but those values can differ across servers due to the manner in which the software is deployed.

Server Metrics

You can retrieve metrics from a given server by querying the TXT records of metrics.status.nip.io
  dig @ns-ovh.nip.io metrics.status.nip.io txt +short
    "Uptime: 13940"
    "Blocklist: 2025-11-07 08:08:50-08 3,773,2"
    "Queries: 58116774 (4169.1/s)"
    "TCP/UDP: 457/58259316"
    "Answer > 0: 18236428 (1308.2/s)"
    "A: 15664900"
    "AAAA: 119999"
    "TXT Source: 3"
    "TXT Version: 3"
    "PTR IPv4/IPv6: 8/0"
    "NS DNS-01: 147"
    "Blocked: 13421"
       
Explanation of Metrics
Uptime
The time since the DNS server has been started, in seconds
Blocklist
The first value ("2023-10-04 07:37:50-07") is the date the blocklist was last downloaded. The following three numbers are the number of CIDR matches that are blocked (e.g. 86.106.104.0/24), the number of IP addresses that are blocked (e.g. 212.64.214.54), and the number of strings that are blocked (e.g. "raiffeisen" is a string that is blocked if it appears in the queried hostname). The blocklist can be found here
Queries
This consists of two numbers: The first is the raw number of DNS queries that the server has responded to since starting operation, and the second is the first number divided by the uptime (i.e. queries/second)
TCP/UDP
This is the number of queries received on the TCP protocol versus the UDP protocol. The sum should equal the number of queries. DNS typically uses the UDP protocol
Answer > 0
This consists of two numbers: the first is the number of queries we responded to with at least one record in the answer section, and the second is the first number divided by the uptime (i.e. queries/second). Note that the number of responses with an answer record is typically a fourth the size of the overall responses. This is normal. One reason for this disparity is that often both the IPv4 (A) and IPv6 (AAAA) records will be checked, but only one reply will have a record in the answer section . For example, browsing to "127.0.0.1.nip.io" generates two lookups, one with an answer (IPv4), and one without (IPv6). Another reason is that lookups follow a chain, e.g. looking up "127.0.0.1.nip.io" may generate up to four queries for A records ("1.nip.io", "0.1.nip.io", "0.0.1.nip.io" and "127.0.0.1.nip.io"), only the last of which returns a record in the answer section. Pro-tip: if you want to shave milliseconds off name resolution, use dashes not dots in your hostname (e.g. "10-9-9-30.nip.io" instead of "10.9.9.30.nip.io")
A
The number of responses which included an A (IPv4) record in the answer section since starting operation (e.g. "dig 127.0.0.1.nip.io")
AAAA
The number of responses which included an AAAA (IPv6) record in the answer section since starting operation (e.g. "dig --1.nip.io aaaa")
TXT Source
The number of responses which included a TXT record of the querier's IP address since starting operation (e.g. "dig @ns.nip.io ip.nip.io txt")
TXT Version
The number of responses which included a TXT record of the DNS's servers version since starting operation (e.g. "dig @ns-hetzner.sslip.io version.status.nip.io txt")
PTR IPv4/IPv6
This consists of two numbers; the first is the number of responses to IPv4 PTR queries (1.0.0.127.in-addr.arpa. → 127-0-0-1.sslip.io.), the second, IPv6 PTR queries
NS DNS-01
The number of responses which included a delegation of the NS (name server) to satisfy a certificate authority's DNS-01 challenge. This lookup is used for generating wildcard certificates from Let's Encrypt and other certificate authority. Technically this is not a "successful" query in that we don't return a record in the ANSWER section, but we do return an NS record in the AUTHORITY section. (e.g. "dig @ns-ovh.nip.io _acme-challenge.192.168.0.1.nip.io. soa")
Blocked
The number of responses which were blocked because we've received a takedown notice. A blocked response is an A or AAAA record to a website which notifies the user that the site they're trying to visit has been blocked because it's unsafe.