Free Online Network Diagnostic Tools

Six browser-based tools for network troubleshooting, security auditing, and performance testing.

How to Choose the Right Network Tool

The right network diagnostic tool depends on the problem you are troubleshooting. Each tool is designed for a specific category of network issue, and using them together can give you a complete picture of what is happening on your network.

Connectivity Issues

If a website or server is unreachable, start with DNS Lookup to verify the domain resolves correctly. If DNS is fine, run a Traceroute to see where packets are being dropped. Use the Port Scanner to confirm the target service port is open and not blocked by a firewall.

Performance Problems

For slow connections, run a Speed Test to measure your actual bandwidth and latency. If speeds are lower than expected, a Traceroute can reveal which network hop is introducing the most delay.

Security Auditing

Before deploying a server, use the Port Scanner to verify only intended ports are exposed. Check your SSL configuration to ensure TLS is properly set up and certificates are valid. Use IP Lookup to investigate suspicious IP addresses in your access logs.