Email Blacklist & IP Reputation Checker
Scan your dedicated mail server IP or sending domain across major real-time anti-spam blocklists (Spamhaus, Barracuda, SpamCop, Invaluement, SORBS). Verify your inbox deliverability status in seconds.
What is an Email DNSBL (DNS Blocklist)?
A DNS-based Blackhole List (DNSBL or RBL) is a real-time database maintained by cybersecurity organizations that tracks IP addresses and domains associated with sending unsolicited bulk email, hosting malware relays, or exhibiting compromised botnet behavior.
Whenever a mail transfer agent (like Gmail or Microsoft Outlook) receives an inbound SMTP connection from your IP address, it queries these blocklists in milliseconds. If your IP address is flagged, the receiving server will reject your message with an SMTP 554 5.7.1 Service unavailable: Client host blocked error or send it straight to the spam folder.
How to Remove an IP from a Blacklist (Delisting Steps)
- Identify the Root Cause: Check if a compromised account on your server was sending unauthorized mail, if your list has high bounce rates, or if you lacked valid Forward-Confirmed Reverse DNS (FCrDNS).
- Fix Authentication & SPF/DKIM: Ensure your SPF, DKIM, and DMARC records are fully validated and aligned before requesting removal.
- Submit a Delisting Request: Click the direct delist links in the results table above. Most major blocklists (such as Spamhaus and Barracuda) allow automated removal once the root issue is resolved.
- Leverage Automated Failover: In CentricSell Mail, if your custom VPS IP is ever flagged, our smart router automatically diverts overflow traffic to secondary cloud ESPs (Amazon SES, SendGrid) so your customer communications are never interrupted.
Automate Deliverability & IP Reputation in 5 Minutes
Stop manually wrestling with DNS records and server configs. CentricSell Mail runs automated pre-flight deliverability checks, provisions dedicated servers over SSH, and routes traffic across Amazon SES, SendGrid, and Mailgun.