With this online UDP port scanner you can scan an IP address for open UDP ports. Use this UDP port scan tool to check what services (dns, tftp, ntp, snmp, mdns, upnp) are running on your server, test if your firewall is working correctly, view open UDP ports. This port scanner runs a UDP scan on an IP address using Nmap port scanner. Do not scan IPs that you do not own, this action may be triggered and blocked by security services.