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📡 UDP Port Checker

Check if a UDP port is open (best effort check).

â„šī¸ About UDP Port Checker

The UDP Port Checker performs a 'best effort' test to see if a UDP service (like DNS or NTP) is responding. Unlike TCP, UDP is connectionless, making it harder to verify if a port is truly open without service-specific packets.

📖 How to use UDP Port Checker

  1. 1. Enter the host and UDP port.
  2. 2. Click 'Run Tool'.
  3. 3. Note that 'Filtered' often means the port is open but the service didn't respond to an empty packet.

❓ Frequently Asked Questions

Is UDP scanning accurate?

UDP scanning is inherently less reliable than TCP scanning because it relies on the absence of an ICMP 'Destination Unreachable' message.

What is port 53?

Port 53 is the standard port for DNS (Domain Name System) traffic.

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