Deliverability
Blacklist
A database of IP addresses or domains identified as sources of spam. Also called blocklist or DNSBL.
Definition
A blacklist (also called blocklist or DNSBL) is a real-time database of IP addresses and domains identified as sources of spam or malicious activity. Email servers query these lists to decide whether to accept, reject, or filter incoming messages. Being listed on a major blacklist can severely impact email deliverability. There are many blacklists, but only a handful (such as Spamhaus and Barracuda) significantly affect deliverability.
Examples
- Spamhaus SBL - lists known spam sources
- Spamcop - lists IPs reported by spam trap hits
Need help with email verification?
Check addresses through the API or clean a whole list from a CSV upload.
100 free verifications. No credit card required.