What Is a PTR Record and Why It Matters for Email Deliverability

Emails hold immense value, especially for professionals, business leaders, and various organizations. It is an effective and economical communication tool to convey information, and promote a product —or service.

This is why email deliverability remains a crucial aspect for successful email communication, and the most effective email marketing initiatives. Having an email warmup service, such as Warmy.io, especially if you have a new or inactive email. But one of the most underrated features that most email users often neglect is performing a PTR (Pointer) lookup.

Without a properly configured DNS PTR record, even legitimate emails may end up in the spam folder or be outright rejected. 

This blog will explore the fundamentals of PTR records, what role they play in DNS, what it contributes to email authentication, and how it improves your email deliverability.

What Is a PTR Record?

There are two types of DNS records that you should be aware of: PTR (Pointer) records and A records.

A PTR record translates an IP address and confirms which domain name it corresponds to, while an A record maps a domain name and identifies the associated IP address.

Both exist to facilitate a seamless email authentication process and verify the legitimacy of an email server. This process is known as reverse DNS lookup.

Email providers and spam filters use reverse DNS lookup to verify that the IP address sending emails corresponds to its assigned and expected domain. In some cases, you can receive some errors, and if a PTR record is missing, misconfigured, or deemed non-legitimate, emails from that IP address may be flagged as spam or rejected altogether.

The Importance of PTR Records for Email Deliverability

Proper configuration of PTR records are critical for authenticating email, and its deliverability. Failure to configure this warrants severe repercussions. Here are the reasons why PTR records are important. 

Spam Prevention

Email servers usually perform reverse DNS lookups before confirming prior to accepting incoming emails. If they confirm that the IP address lacks a PTR record, servers on the receiving end may consider the email suspicious and will classify it as spam.

Reputable Domains 

Prominent email providers like Gmail, Outlook, and Yahoo utilize various authentication mechanisms to assess sender legitimacy. One of these mechanisms is identifying the validity of your PTR record. It is an ideal process to improve the reputation of your domain, while reducing the likelihood of your emails bouncing, or being rejected.

Compliance of Email Authentication Standards and Strict Email Servers

Some mail servers are configured to reject emails from IP addresses that lack PTR records. If your mail server does not have a correctly set up PTR record, you risk emails not being delivered at all.

It is also important to note that a DNS PTR record works alongside other email authentication protocols such as:

  • SPF (Sender Policy Framework)
  • DKIM (DomainKeys Identified Mail)
  • DMARC (Domain-based Message Authentication, Reporting & Conformance)

These records help ensure that your email server is authorized to send emails on behalf of your domain, reducing spam complaints and improving inbox placement.

PTR Record Example

To better understand how a PTR record works, let’s take a look at an example.

Forward DNS Lookup (A Record Example):

When a user enters a domain name, the A record resolves it to an IP address:

example.com → 192.168.1.10

Reverse DNS Lookup (PTR Record Example):

A PTR record does the opposite—it maps an IP address back to the hostname:

10.1.168.192.in-addr.arpa → example.com

The PTR record is stored in the reverse DNS zone and follows a specific format that includes the reversed IP address appended with .in-addr.arpa (for IPv4) or .ip6.arpa (for IPv6).

How to Perform a PTR Record Check

Ensuring that your PTR record is correctly configured is essential for maintaining good email deliverability. You can perform a PTR record check using the following methods:

1. Using Command Line Tools

On a Linux or macOS terminal, you can use the nslookup or dig command to check your PTR record:

Using nslookup:

nslookup 192.168.1.10

Using dig:

dig -x 192.168.1.10

These commands will return the associated domain name if a PTR record is properly set.

2. Using Online DNS Lookup Tools

Several online tools allow you to check your DNS PTR record, including:

You can simply input the IP address to confirm the corresponding PTR record if available. These tools can also verify if there are no PTR records for your domain’s IP address or if there are any inconsistencies in how it is configured. 

3. Checking with Your Hosting Provider

If you’re using a dedicated IP address, your hosting provider or ISP typically manages PTR records. Contact them to verify or set up your reverse DNS entry.

Setting Up a PTR Record

If your emails are getting sent because of a missing or misconfigured PTR record, you will need to follow these steps for a proper setup. 

Contacting Your ISP or Hosting Provider

Most Internet Service Providers (ISPs) manage PTR records for their clients. You can get in touch with them and request for a creation or modification of your reverse DNS record entry and configure it to match your forward DNS record. This ensures the precision of your PTR records which are the essentials for a reputable email service, and ensure email deliverability. 

Provide the Correct Information

When setting up a PTR record, ensure that:

  • The IP address is mapped to the correct domain name.
  • The forward DNS record (A record) matches the reverse DNS record (PTR record).

Verify the Changes

After the PTR record is created, perform a PTR record check using the command-line or online tools mentioned earlier to ensure it is correctly configured.

Monitor Email Deliverability

Regularly monitor your email deliverability metrics, including bounce rates and spam complaints, to confirm that your PTR record is functioning as expected. You can also acquire some tips on how to improve it and ensure a reputable domain. 

Some Common Issues You Should Know with PTR Records

You can encounter tons of issues when setting up a PTR record. The good thing is most of them are resolvable. Here are the following issues that you can encounter. 

Missing PTR Record

Some ISPs do not set up PTR records by default, leading to deliverability problems. Always verify and request a PTR record setup if necessary.

Misconfigured Forward and Reverse DNS Records

A common misconfiguration occurs when the A record and PTR record do not match. Ensure that both point to the same domain.

Shared IP Addresses

If you are using a shared IP address, configuring a PTR record may be challenging since multiple domains use the same IP. Consider using a dedicated IP for better control over email authentication.

Slow DNS Propagation

Changes to PTR records may take time to propagate across DNS servers. Allow up to 24-48 hours for updates to take full effect.

Employing Warmy.io To Verify Your Domain Name Settings

A fully configured PTR record is just one of the many necessities you need to employ to guarantee a reputable and trustworthy email domain. However, proper configuration of PTR records are not sufficient to maintain a healthy email domain and may lack the properties needed to implement actual email deliverability. 

Warmy.io is known for its free email deliverability test, but it also contributes to your reverse DNS lookup by providing free SPF and DMARC records generators, two essential email protocols that work alongside PTR records configuration.

Warmy.io is also an ideal tool for your overall email system needs. It provides features such as:

Email Warmups

Having new, inactive, or dormant email addresses that suddenly send a high volume of messages can be a red flag for many ISPs. This is because these emails lack an established reputation, making ISPs question their authenticity, which can result in them being blacklisted and sent to spam.

Warmy’s email warm-up process prevents your emails from being marked as spam by gradually increasing the sending volume. With our email warmups, you can send up to 5,000 emails per day in a way that avoids suspicion and helps build a reputable email domain.

Warmy automates this process, making it easier to establish credibility with email service providers.

Email Seed List

To guarantee that your email is ready, you can try Warmy’s email seed list.

Warmy’s email seed list can be integrated into your email client to enhance email performance testing.

Our seed list provides genuine email addresses from Gmail and Outlook, which act as “seeds” to improve the testing of your email deliverability. Simply send your emails to these addresses, and in no time, you’ll be able to warm up your email faster, attain professional standing, and improve the reputation and credibility of your email’s deliverability, while addressing any potential issues that may arise.

DNS Records Testing 

Sometimes your emails get sent to spam, not because of your content nor because of non-compliance with proper email etiquettes. In some cases, there are just some misconfigurations in your Domain Name System (DNS). If you are hosting a large number of emails, then you can subscribe to Warmy’s DNS records testing which can help you verify and test up to 100 DNS that ensures your mail server has a healthy setting. 

Email Placement Data

Warmy offers inbox placement data that provides you with a simple report, or data of where your emails are landing when you send emails to prominent email service providers such as Google, Yahoo, or Outlook. 

Overall Customer Success Support, and Deliverability Consultant

We made sure that navigating our services is a breeze, but we understand if you will need consultation in areas such as deliverability or how to properly utilize our services. We offer 24/7 Zoom calls, and chat support that will not only help you navigate through our system, but make sure that you achieve your long-term goals, and obtain reputable emails through our email deliverability.

Sign up for the 7-day free trial, or book a demo and witness your email engagement soar!

Picture of Daniel Shnaider

Article by

Daniel Shnaider

Picture of Daniel Shnaider

Article by

Daniel Shnaider

Get the week’s
best marketing content

Get the week’s
best marketing content

Ensure your email success

Mailbox Temperature

500 /day

Related Post

Two vertical rounded bars, one orange and one red, beside the text: From Europe to APAC: Mastering Global Email Deliverability in 2024–2025 with 2025 highlighted in blue.

Mastering Global Email Deliverability in 2024–2025

In today’s interconnected world, email as a communication channel is a double-edged sword. It’s easy, quick and allows businesses to

Abstract orange and red rounded bars on the left with dark blue text on the right reading: Are Blacklists Killing Your Emails? A Deep Dive into How They Influence Email Providers 2025.

Are Blacklists Killing Your Emails? A Deep Dive into How They Influence Email Providers

In 2025, email remains one of the best ways to reach prospects and customers. But deliverability isn’t guaranteed—especially if your

Bar chart with four ascending colored bars in yellow, orange, and red. Text reads: How to Avoid Email Blocks: Lessons from MS365s Deliverability Research 2025.

How to Avoid Email Blocks: Lessons from MS365’s Deliverability Research

Email deliverability—crucial yet often elusive goal for businesses aiming to connect with their audience. But there’s a harsh reality: As

The Email Deliverability Playbook: 5 Key Trends That Will Define Inbox Success in 2025

Welcome to the new email landscape where email deliverability has never been more important—or more complex. With inbox providers tightening