PTR record presence
Check whether the IP address has a reverse DNS PTR record.
100% Free • No Signup • Live DNS
Reverse DNS Checker
Check PTR records and forward-confirmed reverse DNS for mail servers and sending IPs — PTR is set by your hosting provider, not your domain DNS panel.
Related checks: Mail reputation involves blacklist status, MX records and SPF.
Free PTR lookup • Live DNS • No signup
Reverse DNS checks require an IP address. If you only have a domain, use DNS Lookup to find its IP first.
Find IP with DNS LookupWhy reverse DNS matters for mail
Many mail systems check PTR records and forward-confirmed reverse DNS (FCrDNS) as part of sender reputation. A missing PTR, generic hostname or mismatch between reverse and forward DNS can cause delivery delays, spam folder placement or rejected connections — even when SPF and DKIM look fine.
What this checker validates
One check reviews PTR records, hostname resolution and forward-confirmed reverse DNS.
PTR hostname
Show the hostname returned by the reverse DNS lookup.
Forward confirmation
Verify whether the PTR hostname resolves back to the original IP.
Mail server suitability
Review whether the reverse DNS setup is suitable for mail server reputation.
IPv4 and IPv6 support
Check reverse DNS for supported IPv4 and IPv6 addresses.
DNS errors
Separate missing PTR records from lookup timeouts and DNS errors.
Common reverse DNS issues this tool can detect
Find PTR and reverse DNS problems that may affect email reputation or server trust.
PTR & hostname
- PTR record missing for the IP
- PTR hostname does not resolve
- Reverse DNS lookup timed out
Forward-confirmed rDNS
- FCrDNS failed — hostname mismatch
- PTR resolves to a different IP
- Multiple PTR records returned
Mail server hostname
- Generic or unclear PTR hostname
- IPv6 reverse DNS not configured
- Hostname unsuitable for mail sending
Configuration review
- PTR set by provider, not domain DNS
- Forward check passes but needs review
- Mail reputation context to verify
For blacklist or MX side-checks, use Blacklist Checker and MX Lookup.
How reverse DNS checking works
Reverse DNS starts with an IP address and finds the hostname assigned to it.
Enter an IP address
We validate the IPv4 or IPv6 address and prepare the reverse DNS lookup.
Query PTR record
The tool checks the reverse DNS PTR record for the IP address.
Verify forward match
We resolve the returned hostname and check whether it points back to the original IP.
When to check reverse DNS
- Setting up a new mail server
- After changing VPS or IP address
- When mail deliverability problems start
- Post-migration server verification
- Before bulk or transactional sending
- Periodic mail infrastructure review
Understanding reverse DNS results
A PTR record maps an IP to a hostname. Forward-confirmed rDNS means that hostname resolves back to the same IP — mail systems often expect this for sending servers.
FCrDNS pass
PTR exists and the hostname resolves back to the same IP.
PTR missing
No reverse record — common for residential IPs; problematic for mail servers.
Mismatch
PTR hostname resolves to a different IP (forward-confirmed rDNS failed).
Generic hostname
PTR uses a provider default name — acceptable for some hosts but worth reviewing for mail.
PTR changes are requested from your hosting provider or IP owner. Use Get Help if you need assistance reviewing rDNS for mail delivery.
Preparing reverse DNS lookup…
Need help fixing PTR or reverse DNS?
Send us your IP or domain report and we’ll review the issue.
Learn more: What is reverse DNS?
PTR records are controlled by the IP owner or hosting provider, not your domain DNS panel. How we check
Frequently asked questions
Reverse DNS maps an IP address back to a hostname using a PTR record.
A PTR record is a DNS record used for reverse lookups. It links an IP address to a hostname.
Many mail systems check reverse DNS as part of email reputation and anti-spam filtering. A missing or mismatched PTR record can affect mail delivery.
Forward-confirmed reverse DNS means the PTR hostname resolves back to the same IP address.
Usually no. Reverse DNS is controlled by the IP owner or hosting provider, so you may need to configure it through your VPS or server provider.
No. The Reverse DNS Checker is free and does not require signup.