IP · BLACKLIST · SPAM DATABASES

IP Blacklist Checker

Test an IP against leading spam blacklists and RBLs. Handy for troubleshooting email delivery problems or verifying a formerly compromised IP.

~/pingie - ip-blacklist
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Provide an IPv4 or IPv6 address to test it against blacklist databases.

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IP blacklist checker: Test any address against major DNSBLs

When an IP address lands on a DNS-based blackhole list (DNSBL), mail servers that consult that list will reject or filter messages from it. The Pingie IP blacklist checker queries multiple DNSBLs simultaneously and reports exactly which lists flag a given address, so you can trace a deliverability problem to its source.

The tool works by reversing the octets of an IPv4 address (or the hex nibbles of an IPv6 address) and performing a DNS lookup against each blacklist zone. A valid DNS response means the IP is listed. An NXDOMAIN response means it is not. No guesswork is involved; the result reflects what a receiving mail server would see in real time.

Why a blacklisted IP address disrupts email delivery

Mail transfer agents check incoming connections against DNSBLs before accepting a message. If the sending IP appears on even one list that the receiving server trusts, the message may be rejected, deferred, or silently dropped. A blacklist ip address checker lets you confirm whether that is happening before you spend time debugging other parts of your mail stack.

Being listed does not always mean the IP is actively sending spam. Shared hosting environments can have an IP flagged because of another tenant on the same server. The Spamhaus PBL, for example, lists dynamic and residential IP ranges by policy, not because of observed spam. Knowing which list flagged the address tells you whether you need to delist or simply route mail through a dedicated relay.

Blacklists checked and what each one covers

The tool queries eight major blacklists in a single run. Each list has a different scope, so the combination gives a broad picture of how the IP is perceived across the email ecosystem.

  • Spamhaus ZEN (zen.spamhaus.org): A combined zone that merges the SBL, XBL, and PBL into one query.
  • Spamhaus SBL (sbl.spamhaus.org): Lists IPs confirmed as spam sources or controlled by spam operations.
  • Spamhaus XBL (xbl.spamhaus.org): Covers IPs running exploits, malware, or open proxies used to send spam.
  • Spamhaus PBL (pbl.spamhaus.org): Flags dynamic and residential ranges that should not send mail directly to the internet.
  • Barracuda (b.barracudacentral.org): Maintained by Barracuda Networks based on spam trap and complaint data.
  • SpamCop (bl.spamcop.net): Built from spam reports submitted by SpamCop users.
  • SURBL (multi.surbl.org): Focuses on IPs associated with URLs found in spam messages.
  • SpamRATS (dnsbl.spamrats.com): Identifies IPs sending unsolicited mail or exhibiting suspicious sending patterns.

Results show the overall blacklisted status, how many lists the IP appears on out of the total checked, and a per-list breakdown of listed or clean for each zone.

How to check an IP address for blacklist listings

The process takes a few seconds and requires only the IP address you want to test.

  1. Navigate to the IP Blacklist Checker from the tool menu.
  2. Enter an IPv4 or IPv6 address in the input field.
  3. Click Check . The tool queries all eight blacklist zones and collects the DNS responses.
  4. Review the results: the overall status at the top, the count of lists the IP appears on, and the individual result for each blacklist.

If the IP is listed on one or more zones, each blacklist has its own delisting process. The per-list results tell you exactly which operators to contact, which saves time compared to guessing or checking lists one by one manually.

When to use this tool

A check ip black list lookup is useful in several common situations for email administrators and network operators.

  • Investigating a sudden drop in email deliverability or bounce rate increase.
  • Verifying a new sending IP before putting it into production.
  • Confirming that a previously listed IP has been removed after a delisting request.
  • Auditing shared hosting or VPS IPs inherited from a previous tenant.
  • Troubleshooting mail rejection errors that reference DNSBL lookups in the bounce message.

For a fuller picture of your email authentication setup, pair this tool with the DMARC checker and the DKIM checker . Blacklist status covers the sending IP, while DMARC and DKIM cover domain-level authentication.

How this ip blacklist check tool compares to manual lookups

Checking a single DNSBL manually means running a reverse-DNS query against one zone at a time. For eight lists that is eight separate operations, and the results need to be interpreted individually. This tool consolidates all eight queries into one request and presents the output in a single structured view.

Tools that check only one or two lists can miss listings that affect deliverability at specific mail providers. Covering Spamhaus, Barracuda, SpamCop, SURBL, and SpamRATS together reflects the range of lists that major mail infrastructure actually consults. If you also need to investigate routing or network ownership for a flagged IP, the ASN lookup can show which autonomous system the address belongs to.

FAQ

A DNSBL (DNS-based Blackhole List) publishes flagged IP addresses through the DNS system. When a mail server receives a connection, it reverses the connecting IP's octets and queries a blacklist zone. If the DNS response returns a valid record, the IP is listed and the server can reject or filter the message. If the response is NXDOMAIN, the IP is not on that list. Each blacklist operator sets its own criteria for listing and delisting.

The tool queries eight zones: Spamhaus ZEN (the combined SBL, XBL, and PBL), Spamhaus SBL, Spamhaus XBL, Spamhaus PBL, Barracuda, SpamCop, SURBL, and SpamRATS. These cover the major lists that mail servers and spam filters commonly consult. The per-list results show which specific zones flagged the address, so you know exactly where to submit a delisting request.

No. The Spamhaus PBL (Policy Block List) lists dynamic and residential IP ranges by policy, not because of observed spam activity. Internet service providers submit their dynamic address pools to the PBL to signal that those IPs should not send mail directly to the internet. If your home or office connection is on the PBL, the correct fix is to route outbound mail through your ISP's or email provider's SMTP relay, not to request removal from the PBL.

Yes. On shared hosting, many accounts share the same IP address. If another tenant on the same server sends spam or runs malware, the IP can be listed on one or more DNSBLs, affecting all accounts that share it. The blacklist ip address checker will confirm whether the IP is listed and on which zones. If you are on shared hosting and the IP is flagged, contact your host or consider moving to a dedicated IP.

Delisting requires contacting each blacklist operator separately, because every list runs its own removal process. Some lists delist automatically after a period of clean sending. Others require you to submit a request through a web form and demonstrate that the underlying issue (spam, malware, or misconfiguration) has been resolved. The per-list results from this tool identify which zones to contact, which is the first step in any delisting effort.

This tool performs reverse DNS lookups against DNSBL zones to determine whether a specific IP address is flagged as a spam source. It operates at the network layer. The DMARC checker retrieves and parses the DMARC DNS record for a domain, which governs how receiving servers handle messages that fail SPF or DKIM alignment. One checks IP reputation; the other checks domain-level authentication policy. Both affect deliverability but at different points in the mail acceptance process.

Yes. The tool accepts both IPv4 and IPv6 addresses. For IPv6, the lookup reverses the full hex nibble representation of the address before querying each blacklist zone, which is the standard method DNSBLs use to index IPv6 addresses. Not all blacklists maintain comprehensive IPv6 coverage, so results may vary by zone, but the tool queries each list and reports whatever response it receives.

Each check queries the live DNS zones of the blacklist operators at the moment you run it. The tool does not cache results between sessions. This means the data reflects the current state of each list at the time of the query. Because blacklist data can change as operators add or remove entries, running the check again after a delisting request will show the updated status.

An error on a specific blacklist entry usually means the DNS query to that zone timed out or returned an unexpected response. This can happen if the blacklist operator's DNS infrastructure is temporarily unavailable or if the zone is undergoing maintenance. It does not indicate that the IP is listed or clean on that zone. Running the check again after a short wait will typically resolve transient DNS errors.

The tool processes the IP address to perform the DNSBL lookups and return results. For details on what data is retained and how it is handled, refer to the privacy policy . As a general practice, avoid entering IP addresses that are not yours or that you do not have authorization to test.

DNSBL listings are one cause of rejection but not the only one. If the IP is clean across all eight zones, the issue may be with your domain's authentication records. Check whether your SPF, DKIM, and DMARC records are correctly configured. The DKIM checker can verify your signing record, and the DMARC checker can confirm your policy record is publishing correctly. Bounce messages often contain the specific rejection reason, which helps narrow down the cause.

Checking a single DNSBL manually means constructing the reversed IP string, appending the zone, and running a DNS query, then repeating that for every list you want to cover. This tool runs all eight queries in one operation and presents the results in a single view with a clear listed or clean status per zone. That consolidation matters because a deliverability problem could stem from any one of the eight lists, and missing a listing means missing the cause.