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Free Blacklist Check

Check whether a public IP or hostname appears on common DNS-based blacklists that can affect email delivery and network reputation.

Common use cases

Frequently asked questions

What is a DNSBL?

A DNSBL is a DNS-based blacklist that can list IPs associated with spam, abuse, open relays, or other unwanted behavior.

Does a listing always mean abuse?

Not always. Treat listings as investigation signals and follow the listed provider’s delisting process when appropriate.

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