Blacklist & DNSBL checker
Enter any domain or IP address to check it against major spam blacklists and DNSBLs. See instantly whether you are listed on Spamhaus, Barracuda, SpamCop, and more.
Frequently asked questions
What is a DNSBL?
A DNSBL (DNS-based Blackhole List) is a real-time database that uses DNS queries to check whether an IP address or domain is associated with spam, malware, or other abusive behavior. Mail servers consult DNSBLs to decide whether to accept or reject incoming email.
Why is my IP blacklisted?
Your IP may be blacklisted because it was used to send spam, host malware, or participate in a botnet. Shared hosting environments can also cause blacklisting if another user on the same IP sends spam. Compromised accounts or misconfigured mail servers are other common causes.
How do I get delisted from a blacklist?
First, identify and fix the root cause (e.g., stop spam, patch vulnerabilities, secure compromised accounts). Then visit the blacklist provider's website and follow their removal or delisting request process. Most providers offer a self-service removal form. Some lists automatically delist IPs after a period of clean behavior.
Which blacklists do you check?
We check major DNSBLs including Spamhaus ZEN, Spamhaus DBL, Barracuda, SpamCop, SORBS, CBL, SURBL, URIBL, and JustSpam. For IP addresses we query IP-based blocklists, and for domains we query domain-based blocklists plus selected IP lists.
More free tools
Link safety checker
Check any URL for spam, phishing, and malware.
Full URL audit
Run link safety, headers, DNS, WHOIS, and SSL in one go.
Bulk URL checker
Check up to 10 links at once and export results as CSV.
Email validator
Validate email addresses: syntax, MX records, disposable detection.
URL unwrapper
See the full redirect chain of short links without clicking.
DNS lookup
Look up A, AAAA, MX, TXT, CNAME, and NS records for any domain.
WHOIS lookup
Find domain registration details: registrar, dates, and nameservers.
HTTP header checker
View HTTP response headers and security headers for any URL.
SSL certificate checker
Check SSL/TLS certificate details, expiry, and chain validity.
IP geolocation lookup
Look up IP address location, ISP, network info, and detect proxies.
URLhaus malware check
Check if a URL or domain is associated with malware distribution.
Password strength checker
Check password strength in your browser. Nothing is sent to our servers.
VirusTotal scanner
Scan URLs and domains against 70+ security engines via VirusTotal.
Domain report
Full safety, SSL, DNS, WHOIS & headers report for any domain.