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What is Reverse DNS?
Perform reverse DNS lookups to find the hostname associated with an IP address. Reverse DNS (rDNS/PTR records) is crucial for email deliverability, security verification, and network troubleshooting.
Key Features
How to Use Reverse DNS
Enter an IP address
Click Submit to lookup
View the hostname associated with the IP
Verify reverse DNS configuration
Common Use Cases
Tips & Best Practices
Ensure your mail server IP has a valid PTR record
The PTR hostname should match your mail server HELO name
Missing reverse DNS can cause emails to be marked as spam
Frequently Asked Questions
Why is reverse DNS important for email?
Many mail servers reject emails from IPs without proper reverse DNS. It's a basic spam prevention check.
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