IP Blacklist Check

IP Blacklist Check — is Your IP Blocked?

The 101IP IP Blacklist Check tool verifies your IP address against 12+ major spam databases and blacklists (DNSBL), including Spamhaus, SpamCop, SORBS, Barracuda and others.

Why check your IP in blacklists?

• email delivery problems — your emails may go to spam if your IP is listed;
• diagnosis of mail server configuration issues;
• checking hosting servers and VPS for spam activity;
• verifying that your IP was removed from a blacklist after delisting.

Which blacklists does 101IP check?

• Spamhaus ZEN — the most authoritative anti-spam blacklist;
• SpamCop BL — spam reports from real users;
• SORBS DNSBL — broad list with multiple categories;
• Barracuda Reputation — used by email security systems;
• UCEPROTECT, Blocklist.de, NiX Spam, WPBL, PSBL and others.

How to remove your IP from a blacklist?

Each blacklist has its own delisting procedure. Usually you need to: eliminate the spam/abuse source on your server, then submit a delisting request via the blacklist's official website. Most listings expire automatically after 1–30 days if the spam activity stops.

Bookmark 101IP and use our free IP blacklist check to monitor your IP reputation.

Frequently Asked Questions

• My IP is clean in all blacklists but emails still go to spam. What could be wrong?

  Besides IP-based blacklists, mail providers such as Gmail and Outlook also evaluate the email content, sender domain reputation and SPF/DKIM/DMARC configuration. We recommend checking your domain via the Domain Blacklist tool and verifying that your SPF record is not overly restrictive. A PTR record that contains words like "dsl" or "dynamic" can also trigger spam filters.

• Can running a Blacklist Check harm my IP or increase spam complaints?

  No. The 101IP service performs passive DNS lookups against public DNSBL databases — the same type of query that mail servers make when evaluating incoming messages. No entries are created in any blacklist and your IP is not flagged in any way. You can check any address as many times as needed.

• My IP ended up in the SORBS list even though we never sent spam. How do I get delisted quickly?

  SORBS automatically adds IP addresses from certain provider subnets, especially dynamic IP ranges. Click the delisting link next to the SORBS entry in the check results and fill out the form with a note such as "clean hosting server" or "misclassified subscriber". SORBS typically processes requests within a few hours. Make sure your PTR record does not contain "dsl" or "dynamic" as that can trigger automatic re-listing.