PTR Record Checker

How to Use the PTR Record Checker

Running a reverse DNS lookup takes seconds. Follow these four steps to verify your PTR record and FCrDNS alignment.

Enter an IP address. Enter an IPv4 address (e.g. 8.8.8.8) or IPv6 address in the input field above.

Select a DNS resolver. Choose your preferred DNS resolver — Google, Cloudflare, OpenDNS, or Quad9.

Click "Lookup PTR Record". Hit the button or press Enter to run the reverse DNS lookup instantly.

Review your results. See the PTR hostname, TTL value, FCrDNS status, and full deliverability check breakdown.

What the PTR Checker Results Mean

Understanding your results helps you diagnose and fix email delivery issues faster.

PTR Hostname

The domain name mapped to your IP address. This is what receiving mail servers see when they perform a reverse DNS lookup on your sending IP.

TTL (Time to Live)

Indicates how long (in seconds) DNS resolvers cache your PTR record.

Lower TTL means faster updates and propagation. Higher TTL means fewer DNS queries but slower updates.

FCrDNS

We verify whether your PTR hostname resolves back to the same IP address using a forward lookup.

Match means FCrDNS confirmed (trusted). Mismatch signals trust and deliverability issues.

Deliverability Checks

We run multiple checks to evaluate your reverse DNS setup and flag anything that may affect inbox delivery.

Check	What it means
PTR Record Exists	Confirms a reverse DNS entry is configured for the IP. Without this, most mail servers will reject or deprioritise your email.
FCrDNS Match	Ensures the PTR hostname resolves back to the same IP via a forward A/AAAA lookup. A mismatch is treated as a spoofing signal by many receivers.
Hostname Quality	Checks whether the hostname is a stable, purpose-named host rather than a generic or dynamic-IP-style name. Generic hostnames score negatively with spam filters even when FCrDNS passes.

Check

What it means

PTR Record Exists

Confirms a reverse DNS entry is configured for the IP. Without this, most mail servers will reject or deprioritise your email.

FCrDNS Match

Ensures the PTR hostname resolves back to the same IP via a forward A/AAAA lookup. A mismatch is treated as a spoofing signal by many receivers.

Hostname Quality

Checks whether the hostname is a stable, purpose-named host rather than a generic or dynamic-IP-style name. Generic hostnames score negatively with spam filters even when FCrDNS passes.

Overall Verdict

Based on all checks, you receive one of three clear statuses.

Status	What it means
Valid & Verified	Reverse DNS is correctly configured with FCrDNS confirmed. Your sending IP is properly identified by receiving mail servers.
Valid, with a note	A PTR record exists and is forward-confirmed, but the hostname looks generic or dynamic. This is worth improving for IPs that send mail.
Not found / not confirmed	No reverse DNS entry was found, or the PTR is not forward-confirmed. This commonly causes email deliverability problems — contact your hosting provider or ISP.

Status

What it means

Valid & Verified

Reverse DNS is correctly configured with FCrDNS confirmed. Your sending IP is properly identified by receiving mail servers.

Valid, with a note

A PTR record exists and is forward-confirmed, but the hostname looks generic or dynamic. This is worth improving for IPs that send mail.

Not found / not confirmed

No reverse DNS entry was found, or the PTR is not forward-confirmed. This commonly causes email deliverability problems — contact your hosting provider or ISP.

What Is a PTR Record?

A PTR (Pointer) record is the DNS record type used for reverse DNS lookups — mapping an IP address back to a hostname. Unlike A records which go from hostname to IP, PTR records go in the opposite direction.

Reverse DNS mapping

PTR records live in the in-addr.arpa zone (IPv4) or ip6.arpa zone (IPv6). They map an IP back to a hostname — the opposite of an A record.

Critical for deliverability

Receiving mail servers check PTR records before accepting email. A missing or mismatched PTR is one of the most common causes of email being rejected or sent to spam by Gmail, Microsoft 365, and Yahoo.

Controlled by your IP owner

PTR records are set by whoever owns the IP address block — your hosting provider or ISP — not your domain registrar. To add or update a PTR record, contact your provider directly.

Common PTR Record Errors and How to Fix Them

Most PTR problems fall into four categories. Here's what each means and the exact steps to resolve it.

No PTR record

Missing reverse DNS

The IP has no PTR entry in the in-addr.arpa zone. This is the most common cause of email rejection by major providers — Gmail, Microsoft 365, and Yahoo all require a valid PTR.

Contact your hosting provider or ISP and request a PTR record pointing to your mail server hostname.

FCrDNS mismatch

PTR hostname doesn't resolve back

A PTR record exists, but the returned hostname doesn't resolve back to the original IP via an A/AAAA record, or resolves to a different IP. FCrDNS fails and receivers treat this as suspicious.

Ensure the A record for your PTR hostname points exactly to the same IP that holds the PTR record.

Generic hostname

PTR resembles a dynamic/residential IP

Your PTR exists and FCrDNS passes, but the hostname pattern resembles a dynamically assigned IP (e.g. pool-71-124-0-1.nycmny.fios.verizon.net). Spam filters score this negatively.

Request a custom PTR from your provider that matches your mail hostname (e.g. mail.yourdomain.com).

PTR / EHLO mismatch

PTR hostname differs from EHLO banner

Your SMTP server announces one hostname in EHLO, but the PTR record on its sending IP points to a different hostname. Many spam filters treat this inconsistency as a misconfiguration signal.

Align your PTR hostname with the hostname your mail server uses in its EHLO/HELO announcement.

Frequently Asked Questions

What is a PTR record?

A PTR (Pointer) record is the DNS record type used for reverse DNS lookups — mapping an IP address back to a hostname. Unlike A records (hostname → IP), PTR records go in the opposite direction (IP → hostname). They live in a special area of DNS called the reverse DNS tree: the in-addr.arpa zone for IPv4 and ip6.arpa for IPv6.

Can I set my own PTR record?

Not directly through your domain’s DNS zone. PTR records are controlled by the owner of the IP address block, which is your hosting provider or ISP — not the domain owner. You need to contact your provider and request a custom PTR that points to your mail server hostname. Most reputable hosting providers support this for dedicated IPs, and cloud providers (AWS, GCP, Azure) allow PTR configuration through their console or support.

How long does it take for a PTR record to propagate?

PTR records propagate just like any other DNS record. Once your provider sets or updates the PTR, propagation typically takes 15 minutes to a few hours depending on the TTL of the reverse zone and DNS resolver caching. Use this tool to confirm the new PTR is visible once propagation completes.

Why does my email go to spam even though I have a PTR record?

A PTR record alone is not sufficient. FCrDNS must also pass — meaning the hostname in your PTR record must resolve back to the original IP via an A/AAAA record. If they don’t match, many mail servers treat it the same as having no PTR. Additionally, generic or dynamic-IP-style PTR hostnames (e.g. pool-71-192-0-1.nycmny.fios.verizon.net) still attract spam scoring even when FCrDNS passes. Make sure your PTR hostname, forward A record, and EHLO/HELO banner are all consistent — and that SPF, DKIM, and DMARC are also configured.

What is FCrDNS and why does it matter?

FCrDNS (Forward-Confirmed Reverse DNS) is a two-step check: first, the PTR record for an IP returns a hostname; second, that hostname is looked up via A/AAAA record to confirm it resolves to the original IP. Both must succeed for FCrDNS to pass. Receiving mail servers use FCrDNS to verify the PTR isn’t just an orphaned record — it confirms the IP and hostname are genuinely linked in both directions, which is a strong indicator of a legitimate mail server.

Is a PTR record the same as reverse DNS?

Yes — PTR records are the DNS record type used to implement reverse DNS. The terms are used interchangeably. A “reverse DNS lookup” or “rDNS lookup” is the act of querying a PTR record for an IP address, which returns the associated hostname.