Free, privacy-respecting tools to inspect, diagnose, and secure your internet connection.
Get geolocation, ISP, ASN, and hostname for any IP.
Resolve a domain name to its IP addresses.
Look up registration details for a domain or IP.
Check if an IP is on common DNSBL spam lists.
Detect DNS queries leaking outside your VPN.
Find IPs leaking through WebRTC in your browser.
Test if a TCP port is open on a given host.
Measure your download, upload, and ping.
Compute CIDR ranges, masks, and host counts.
Trace the origin of an email from its headers.