Reverse DNS Lookup
Inspect PTR records and forward-confirmed reverse DNS for an IP address.
Reverse DNS Lookup is a technical PTR diagnostic tool. Enter a public IPv4 or IPv6 address to query its reverse DNS name, inspect PTR records, and check whether returned hostnames resolve back to the same IP address.
Reverse DNS Lookup
Enter the required values and run the tool to view results.
Recommended Next Checks
Continue the same task with related tools. When possible, your current input is carried to the next page.
IP to Hostname Lookup
Find hostnames associated with a public IP address.
IPv6 AAAA Lookup
The AAAA record type of the DNS is a 128-bit IPv6 address that maps to a hostname.
NS Lookup
Lookup NS (name server) records for the domain name in the DNS system.
DMARC Lookup
Lookup DMARC records for the domain name in the DNS system.
How to use Reverse DNS Lookup
Enter a public IP address and run the tool. The result shows the reverse DNS query name, PTR records, and forward-confirmation status for each returned hostname.
What is a PTR record?
A PTR record maps an IP address back to a hostname. IPv4 reverse DNS uses the in-addr.arpa namespace, while IPv6 reverse DNS uses the ip6.arpa namespace. Reverse DNS is normally managed by the IP address owner, hosting provider, ISP, or cloud provider.
Why forward-confirmed reverse DNS matters
Forward-confirmed reverse DNS means the IP has a PTR hostname and that hostname resolves back to the same IP address. This is useful for mail server validation, infrastructure identity checks, abuse triage, and diagnosing missing or mismatched PTR records.
Reverse DNS Tips
For mail servers, configure a meaningful PTR record and make sure the PTR hostname resolves back to the sending IP. For a simplified answer that only lists hostnames, use the IP to Hostname tool.
Related Tools
IP to Hostname Lookup
Find hostnames associated with a public IP address.
IPv6 AAAA Lookup
The AAAA record type of the DNS is a 128-bit IPv6 address that maps to a hostname.
NS Lookup
Lookup NS (name server) records for the domain name in the DNS system.
DMARC Lookup
Lookup DMARC records for the domain name in the DNS system.
DKIM Validator
Validate a DKIM selector and public key record.
Mail Server Test
Check a mail domain for MX records, public mail host addresses, PTR records, SPF, DMARC, SMTP banner, EHLO, and STARTTLS support.
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