Reverse DNS

Look up the hostname (PTR record) for any IP address.

What This Tool Does

Our reverse DNS lookup tool queries PTR records to find the hostname associated with an IP address. This is the opposite of a regular DNS lookup—instead of domain to IP, it resolves IP to domain. Reverse DNS is commonly used for email server verification, network diagnostics, and identifying the owner of an IP address.

Common Use Cases

Verify email server configuration (required for reliable email delivery)
Identify the hostname of servers in network logs
Debug network issues by identifying device names
Check if reverse DNS is properly configured for your servers
Investigate suspicious IP addresses in security logs

Frequently Asked Questions

Why is reverse DNS important for email?

Many email servers check that the sending IP's reverse DNS matches the sending domain. Missing or mismatched PTR records often cause emails to be marked as spam or rejected entirely. Proper rDNS configuration is essential for email deliverability.

Why doesn't my IP have a reverse DNS record?

PTR records must be set up by whoever controls the IP address—usually your ISP or hosting provider. Many residential ISPs don't configure reverse DNS by default. Contact your provider to request PTR record setup.

Can I set my own reverse DNS?

Only the owner of the IP address block can set PTR records. For most users, this means contacting your ISP or hosting provider. Cloud providers like AWS, Azure, and GCP allow you to configure reverse DNS through their control panels.

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