How do I check if a UDP port is open online?

Enter a host and UDP port (e.g. 8.8.8.8:53) in the UDP checker. The tool sends protocol-appropriate payloads from 50+ global nodes — for example, a real DNS query to port 53 or an NTP request to port 123 — and reports whether a valid response was received from each location.

Why does UDP port testing require a payload?

Unlike TCP, UDP has no handshake. An empty packet sent to most UDP services produces no response because the application is waiting for meaningful data before replying. The tool automatically injects the correct payload for known ports (DNS/53, NTP/123, SNMP/161, game servers/27015) to get a real, meaningful response.

How do I test if my VPN UDP port is reachable?

Enter your VPN server IP and port (typically UDP 1194 for OpenVPN or UDP 51820 for WireGuard) and run the UDP check. Results from multiple global nodes will show whether your VPN port is accessible worldwide or blocked by specific ISPs or regional networks.

Can I test game server ports with this UDP checker?

Yes. For Source Engine game servers (CS:GO, TF2, Rust) on port 27015, the tool automatically sends a valid Source Engine query packet. For other game servers, you can enter a custom hex payload in the advanced options. Results show which global regions can reach your game server.

Report for gr-ath-otenet.check-host.eu:80

Name: Check-Host gr-ath-otenet.check-host.eu:80 UDP Port Reachability Check
Author: Check-Host

Info Ping HTTP TCP UDP MTR DNS

report.report_types.udp gr-ath-otenet.check-host.eu:80

Checked Apr 21, 2026 00:42:46 UTC |

| Check again |

ठिकाण	निकाल	वेळ	IP Address
Albania, Tirana	Timeout	-	62.103.245.172
Australia, Sydney	Timeout	-	62.103.245.172
Bosnia and Herzegovina, Novi Travnik	Timeout	-	62.103.245.172
Bulgaria, Sofia	Timeout	-	62.103.245.172
Canada, Montreal	Timeout	-	62.103.245.172
Switzerland, Bern	Timeout	-	62.103.245.172
Chile, Santiago	Timeout	-	62.103.245.172
China, Hohhot	Timeout	-	62.103.245.172
Germany, Nuernberg	Timeout	-	62.103.245.172
Germany, Frankfurt am Main	Timeout	-	62.103.245.172
Germany, Frankfurt am Main	Timeout	-	62.103.245.172
Germany, Limburg	Timeout	-	62.103.245.172
Germany, Frankfurt am Main	Timeout	-	62.103.245.172
Germany, Duesseldorf	Timeout	-	62.103.245.172
Denmark, Glostrup Municipality	Timeout	-	62.103.245.172
Spain, Bilbao	Timeout	-	62.103.245.172
Finland, Helsinki	Timeout	-	62.103.245.172
Finland, Helsinki	Timeout	-	62.103.245.172
France, Gravelines	Timeout	-	62.103.245.172
France, Paris	Timeout	-	62.103.245.172
United Kingdom, London	Timeout	-	62.103.245.172
Georgia, Tbilisi	UDP checks unavailable: SOCKS5 proxy does not support UDP ASSOCIATE	-	gr-ath-otenet.check-host.eu
Greece, Athens	UDP checks unavailable: SOCKS5 proxy does not support UDP ASSOCIATE	-	gr-ath-otenet.check-host.eu
Hong Kong, Hong Kong	Timeout	-	62.103.245.172
Croatia, Zagreb	Timeout	-	62.103.245.172
Hungary, Budapest	Timeout	-	62.103.245.172
Indonesia, Jakarta	Timeout	-	62.103.245.172
Israel, Petach Tikwa	Timeout	-	62.103.245.172
Israel, Netanja	Timeout	-	62.103.245.172
India, New Delhi	Timeout	-	62.103.245.172
Iceland, Reykjavik (Miðborg)	Timeout	-	62.103.245.172
Italy, Como	Timeout	-	62.103.245.172
Kuwait, Kuwait City	UDP checks unavailable: SOCKS5 proxy does not support UDP ASSOCIATE	-	gr-ath-otenet.check-host.eu
Lithuania, Pilaite	Timeout	-	62.103.245.172
Latvia, Riga	Timeout	-	62.103.245.172
Moldova, Chisinau	Timeout	-	62.103.245.172
Netherlands, Amsterdam	Timeout	-	62.103.245.172
Netherlands, Amsterdam	Timeout	-	62.103.245.172
Netherlands, Amsterdam	Timeout	-	62.103.245.172
Netherlands, Amsterdam	Timeout	-	62.103.245.172
Norway, Oslo	Timeout	-	62.103.245.172
Poland, Warsaw	Timeout	-	62.103.245.172
Romania, Bacău	Timeout	-	62.103.245.172
Romania, Bucharest	Timeout	-	62.103.245.172
Serbia, Belgrade	Timeout	-	62.103.245.172
Russia, St Petersburg	Timeout	-	62.103.245.172
Singapore, Singapore	Timeout	-	62.103.245.172
Turkey, Istanbul	Timeout	-	62.103.245.172
Taiwan, Taipei	Timeout	-	62.103.245.172
United States, Miami	Timeout	-	62.103.245.172
United States, Dallas	Timeout	-	62.103.245.172
United States, Kansas City	Timeout	-	62.103.245.172
United States, Dallas	Timeout	-	62.103.245.172
South Africa, Johannesburg	Timeout	-	62.103.245.172