What is an IP Blacklist?
An IP blacklist, also known as a Real-time Blackhole List (RBL) or DNSBL, is a database of IP addresses, domains, or IPv6 addresses known for sending spam, hosting malware, or engaging in other abusive activities. Being listed can prevent email delivery or block access to services.
Why Check Blacklist Status?
- Ensure your emails reach inboxes and avoid spam filters.
- Maintain a good reputation for your IP or domain.
- Detect if your server has been compromised or misused.
- Prevent downtime or blocks from major providers.
How It Works
This tool queries multiple RBL databases by performing DNS lookups. If the lookup returns a specific response (e.g., 127.0.0.x), the IP/domain is listed. We check against comprehensive lists including Spamhaus, SORBS, UCEPROTECT, and more, updated for 2025.