Free Email Blacklist Checker
Instantly check whether a domain's mail server IPs are listed on any of 7 major DNSBLs.
Need to monitor this across every client domain you manage? ActiScan does bulk scanning, scoring, and white-labeled reporting for MSPs.
How to Use the Blacklist Checker
Enter a domain
No http:// prefix – just the domain itself (e.g. company.com).
Click Check
ActiScan resolves the domain's mail server IPs and queries each one against 7 DNSBLs, live.
Read the result
A pass/warn/fail status plus exactly which list(s), if any, flagged an IP.
What Your Result Means
Listed – critical/high severityFailA mail server IP was found on Spamhaus, SpamCop, or Barracuda. Outbound mail from this domain is likely being rejected or sent straight to spam right now – delisting should happen as soon as possible.
Listed – medium severityWarnA mail server IP was found only on a lower-impact list (SORBS, PSBL, Invaluement, or SPFBL). Deliverability impact is usually smaller, but it's still worth requesting delisting.
Not listedPassNone of the domain's mail server IPs turned up on any of the 7 DNSBLs checked.
Not applicableInfoShown when the domain has no MX records, its mail server hostnames didn't resolve to an IPv4 address, or – most commonly – mail is hosted on a shared platform like Google Workspace or Microsoft 365. Checking a shared IP's reputation wouldn't tell you anything about this one tenant, so the check is skipped.
What is an Email Blacklist?
An email blacklist – more precisely a DNSBL, or DNS-based Blacklist – is a published list of IP addresses that mail providers consult before accepting inbound email. If a mail server's sending IP shows up on one, receiving servers may reject the message outright or route it straight to spam, regardless of how well SPF, DKIM, and DMARC are configured on the sending domain.
This checker looks up the domain's MX records, resolves each mail server hostname to its IPv4 address(es), then queries every address against 7 DNSBLs using the same reversed-IP DNS lookup those lists use themselves. If mail is hosted on a large shared platform, the check is skipped – a single tenant on Google Workspace or Microsoft 365 doesn't control that shared IP's reputation, so a listing there wouldn't be actionable anyway.
DNSBLs This Checker Queries
| DNSBL | Severity | Delisting page |
|---|---|---|
| Spamhaus | Critical | check.spamhaus.org/ |
| SpamCop | High | www.spamcop.net/bl.shtml |
| Barracuda | High | www.barracudacentral.org/rbl/removal-request |
| SORBS | Medium | www.sorbs.net/lookup.shtml |
| PSBL | Medium | psbl.org/remove |
| Invaluement | Medium | www.invaluement.com/removal/ |
| SPFBL | Medium | spfbl.net/en/ |
Why Domains Get Blacklisted – and How Delisting Works
The usual causes are a compromised mailbox or account sending spam without the owner's knowledge, a misconfigured or open mail relay, sharing an IP with a bad neighbor on cheap hosting, or a legitimate sender simply pushing volume or content that trips a DNSBL's spam filters.
Delisting isn't a single universal process – each DNSBL operator runs its own removal request form (see the table above), typically expects you to have already fixed the underlying cause, and can take anywhere from minutes to a few days to take effect once submitted. There is no one-click fix that clears every list at once.
Next Steps After Your Check
Listed on a DNSBL?
Start with whichever list(s) your result named – each has its own delisting request form.
See delisting links ↑Want to catch it before clients complain?
ActiScan monitors blacklist status on a schedule and alerts you the moment something changes.
Start free trial →Check the rest of your email authentication
A clean blacklist result doesn't mean SPF, DKIM, and DMARC are set up correctly.
Check your DMARC record →Frequently Asked Questions
Is this blacklist checker free?
Yes – check any domain's mail servers against all 7 DNSBLs for free, no signup required.
Which blacklists does it check?
Spamhaus, SpamCop, Barracuda, SORBS, PSBL, Invaluement, and SPFBL – every IP address the domain's mail servers resolve to is queried against all 7.
Why does my result say the check doesn't apply to my domain?
Usually because mail is hosted on a shared platform like Google Workspace, Microsoft 365, Mimecast, or Proofpoint – the provider manages that shared IP's reputation, not you. It can also mean the domain has no MX records at all.
What's the difference between a fail and a warn result?
Fail means an IP was found on at least one higher-severity list (Spamhaus, SpamCop, or Barracuda). Warn means it only turned up on a lower-severity list (SORBS, PSBL, Invaluement, or SPFBL).
How long does delisting take once I request it?
It varies by operator – anywhere from minutes to a few days after you submit a removal request and, if required, fix whatever caused the listing in the first place.