IP Blacklist Check
Check a public IP against spam, abuse, and attack-related DNS blocklists.
About this tool
Check whether a public IP address appears on widely used DNS blocklists (DNSBL/RBL). These lists flag sources of spam, compromised hosts, brute-force attacks, port scans, and other abusive traffic — the same reputation signals mail servers and firewalls consult.
What you get
- Overall verdict: clean or listed, with category hints (spam, attacks, abuse)
- Per-list status across spam, attack, and bot/proxy blocklists
- Human-readable listing reasons when a provider publishes return codes
- Permalink and Recheck for repeated lookups
How to use
Your IP is prefilled when possible. Enter any public IPv4 or IPv6 address and click Check blacklists. A clean result on these lists does not guarantee good reputation everywhere — and a listing may be temporary or disputed.
FAQ
How to check if an IP is blacklisted?
Enter an IPv4 address to query multiple DNS-based blocklists for spam and abuse listings, with an overall clean or listed verdict.
Why would an IP address be on a blocklist?
Outbound spam, compromised hosts, open relays, or attack traffic trigger listings—mail and security filters then reject connections from that IP.
How to test email server IP reputation?
Check the sending IP before troubleshooting delivery failures—a listed IP explains bounces and spam-folder placement.
What to do if my IP is blacklisted?
Fix the root cause (compromise, open relay, spam source), then follow each list's delisting process after traffic is clean.
By using this tool you agree to our Terms of Use and Privacy Policy. Results are provided as-is without warranty.