Blacklist Checker Tool
Check if a domain or its IP address appears on common DNS-based blacklists (DNSBLs). Identify deliverability issues before they affect your email reputation.
What are DNS blacklists?
DNS-based blacklists (DNSBLs) are real-time databases that track IP addresses and domains known to send spam or host malicious content. Mail servers query these lists during delivery to decide whether to accept, reject, or flag incoming messages. Being listed on a DNSBL can cause your emails to bounce or land in spam folders.
Why check blacklist status?
Even legitimate senders can end up on a blacklist due to a compromised account, misconfigured mail server, or a shared IP with a bad neighbor. Regular blacklist checks help you catch listing issues early, before they damage your sender reputation or disrupt business-critical email delivery.
What if my IP is listed?
First, identify the root cause: check for open relays, compromised accounts, or spam-like sending patterns. Once resolved, most blacklists offer a removal (delisting) request process. Some lists automatically delist after a cooling-off period if no further abuse is detected. Shared hosting or CDN IPs may show false positives since multiple tenants share the same address.
FAQ
Frequently asked questions
Is this blacklist checker free?+
Yes, completely free. No signup or credit card required. Check any domain against multiple DNS-based blacklists instantly.
Which blacklists do you check?+
We check against well-known DNSBLs including Spamhaus ZEN, SpamCop, Barracuda, SORBS, and the Spamhaus Domain Block List (DBL). These lists are among the most widely used by mail servers worldwide.
Why does it say my IP is on a shared hosting platform?+
If your domain resolves to a CDN (like Cloudflare or Vercel) or shared hosting IP, other tenants on the same IP may have caused a listing. In these cases, the blacklist result may not reflect your domain specifically. Contact your hosting provider if you suspect a shared-IP blacklisting is affecting your deliverability.
How do I get removed from a blacklist?+
Each blacklist has its own delisting process. Visit the blacklist provider's website (e.g., spamhaus.org) and follow their removal instructions. You will typically need to demonstrate that the underlying issue has been fixed. Automated delisting can take anywhere from a few hours to several days.
Blacklist Checker Tool is just the start.
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