Email Blacklist Checker

Check if your domain or IP address is listed on major email blacklists (DNSBLs). Being blacklisted can severely impact your email deliverability and sender reputation.

Check Email Blacklists

Check if your domain or IP is listed on major email blacklists

About email blacklists

Email blacklists (DNSBLs) are real-time databases of IP addresses and domains known for sending spam. Major email providers check these lists to filter incoming mail.

Most impactful blacklists:

Spamhaus - Used by most major providers
Barracuda - Common in enterprise
SpamCop - User-reported spam
SORBS - Aggregated spam sources

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About this tool

This free utility is designed to help email marketers and developers improve their deliverability and campaign performance. At Sequenzy, we believe in providing transparent, helpful tools for the community.

Frequently Asked Questions

An email blacklist (DNSBL) is a real-time database of IP addresses and domains known to send spam. Email servers check these lists and may reject or filter emails from listed senders.

The most impactful blacklists are Spamhaus (SBL, XBL, PBL), Barracuda, SORBS, SpamCop, and CBL. Being listed on Spamhaus can block delivery to a large portion of the internet.

Each blacklist has its own removal process. First, fix the issue that caused listing (spam complaints, compromised server, etc.). Then submit a delisting request through the blacklist's website. Most have self-service removal.

Common causes include: high spam complaint rates, sending to purchased lists, compromised email accounts, poor list hygiene (too many bounces), or sharing an IP with spammers on shared hosting.

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