Blacklist Checker

An email blacklist (RBL/DNSBL) is a database of IP addresses and domains known for sending spam or malicious content. Email servers query these lists to filter incoming mail and protect users from unwanted messages.

Use this tool to check your IP address or domain against 70+ major blacklists. If you're listed, the results will show which blacklists have flagged you and may provide reasons for the listing.

Common reasons include: sending spam or bulk unsolicited emails, having a compromised server or account, missing or incorrect SPF/DKIM/DMARC records, high bounce rates, spam trap hits, or sharing an IP with spammers.

Being blacklisted can severely impact email deliverability. Mail servers may reject your emails outright, mark them as spam, or delay delivery. This hurts your sender reputation and prevents legitimate emails from reaching recipients.

IP blacklists (RBL) track sending servers by IP address, while domain blacklists (DBL) track domains found in email content or headers. Both are important for email reputation. Always check both your server IP and sending domain.

First, fix the underlying issue (stop spam, secure your server, implement authentication). Then visit the blacklist's website and submit a delisting request. Some blacklists automatically delist after 24-72 hours of clean behavior.

These are email authentication protocols: SPF (Sender Policy Framework) verifies authorized sending IPs, DKIM (DomainKeys Identified Mail) adds a digital signature, and DMARC (Domain-based Message Authentication) specifies handling policies. All help prevent blacklisting.

Check weekly if you send regular emails, or daily for high-volume senders. Set up automated monitoring to receive instant alerts when you're blacklisted. Early detection allows faster remediation and minimal impact on deliverability.

Timeouts occur when a blacklist's DNS server is slow or unreachable. This is normal for a few blacklists and doesn't mean you're listed. If you see many timeouts, your network may have connectivity issues or some blacklists may be offline.

Yes! Best practices include: use double opt-in for email lists, never buy email lists, implement SPF/DKIM/DMARC, monitor bounce rates, maintain good list hygiene, use a dedicated IP for sending, and promptly handle abuse complaints.

A 'listed' status means the blacklist has actively flagged your IP/domain (bad). A 'timeout' means the DNS query didn't complete in time (neutral - not necessarily listed). Timeouts can happen due to network issues or slow blacklist servers.

No. Major blacklists like Spamhaus, SORBS, and SpamCop are more widely used by email providers. Being listed on these has a bigger impact on deliverability. Smaller or less reputable blacklists may have less strict criteria and fewer consequences.