BLACKLIST & SECURITY
Security Check
Check a public IPv4 address against live DNS-based blacklist sources, review reverse DNS, and inspect basic network security signals without generating fake risk scores.
LIVE SECURITY SUMMARY
Ready to check
Enter a public IPv4 address or use your current IP.
SECURITY SIGNALS
What This Check Can Tell You
Blacklist Status
See whether supported DNSBL sources return a positive listing for the checked public IPv4 address.
Reverse DNS
Review the PTR hostname returned by DNS when one is published for the public address.
Source Transparency
Every blacklist source appears individually so you can see which provider returned a positive result.
No Fake Score
SpeedMeter does not invent a trust percentage. It reports the live checks that the server was able to complete.
HOW IT WORKS
Three Steps to Check an IP
Enter or Detect IP
Use your current public IPv4 address or enter another public IPv4 address.
Query DNSBL Sources
The server reverses the IPv4 octets and queries supported DNS-based blacklist zones.
Review Live Results
See positive listings, non-listings, reverse DNS, and unavailable sources in one clear panel.
COMMON QUESTIONS
Security Check Questions
Does a clean blacklist result guarantee my IP is safe?
No. It only means the DNSBL sources successfully checked did not return a positive listing at that moment.
Why can a blacklist source show unavailable?
Some DNSBLs limit public resolvers, require registration, or may temporarily fail. SpeedMeter shows that state instead of pretending the source was checked.
Can I check private IP addresses?
No. The blacklist tool is designed for public IPv4 addresses. Private and reserved addresses are rejected because they are not internet-routable public IPs.