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 8.8.8.8:53

Info Ping HTTP TCP UDP MTR DNS

report.report_types.udp 8.8.8.8:53

report.used_payload:

0x241a010000010000000000000377777706676f6f676c6503636f6d0000010001

Checked Apr 20, 2026 15:01:38 UTC |

| Check again |

Location	Result	Time	IP Address
Albania, Tirana	OPEN	77.0 ms	8.8.8.8
Australia, Sydney	OPEN	4.0 ms	8.8.8.8
Bosnia and Herzegovina, Novi Travnik	OPEN	38.0 ms	8.8.8.8
Bulgaria, Sofia	OPEN	1.0 ms	8.8.8.8
Canada, Montreal	OPEN	2.0 ms	8.8.8.8
Switzerland, Bern	OPEN	2.0 ms	8.8.8.8
Chile, Santiago	OPEN	2.0 ms	8.8.8.8
China, Hohhot	OPEN	13.0 ms	8.8.8.8
Germany, Nuernberg	OPEN	4.0 ms	8.8.8.8
Germany, Frankfurt am Main	OPEN	4.0 ms	8.8.8.8
Germany, Frankfurt am Main	OPEN	3.0 ms	8.8.8.8
Germany, Limburg	OPEN	2.0 ms	8.8.8.8
Germany, Frankfurt am Main	OPEN	3.0 ms	8.8.8.8
Germany, Duesseldorf	OPEN	9.0 ms	8.8.8.8
Denmark, Glostrup Municipality	OPEN	34.0 ms	8.8.8.8
Spain, Bilbao	OPEN	38.0 ms	8.8.8.8
Finland, Helsinki	OPEN	36.0 ms	8.8.8.8
Finland, Helsinki	OPEN	13.0 ms	8.8.8.8
France, Gravelines	OPEN	10.0 ms	8.8.8.8
France, Paris	OPEN	46.0 ms	8.8.8.8
United Kingdom, London	OPEN	6.0 ms	8.8.8.8
Georgia, Tbilisi	UDP checks unavailable: SOCKS5 proxy does not support UDP ASSOCIATE	-	8.8.8.8
Greece, Athens	UDP checks unavailable: SOCKS5 proxy does not support UDP ASSOCIATE	-	8.8.8.8
Hong Kong, Hong Kong	OPEN	9.0 ms	8.8.8.8
Croatia, Zagreb	OPEN	170.0 ms	8.8.8.8
Hungary, Budapest	OPEN	44.0 ms	8.8.8.8
Indonesia, Jakarta	OPEN	16.0 ms	8.8.8.8
Israel, Petach Tikwa	OPEN	47.0 ms	8.8.8.8
Israel, Netanja	OPEN	49.0 ms	8.8.8.8
India, New Delhi	OPEN	2.0 ms	8.8.8.8
Iceland, Reykjavik (Miðborg)	Timeout	-	8.8.8.8
Kuwait, Kuwait City	UDP checks unavailable: SOCKS5 proxy does not support UDP ASSOCIATE	-	8.8.8.8
Lithuania, Pilaite	OPEN	176.0 ms	8.8.8.8
Latvia, Riga	OPEN	173.0 ms	8.8.8.8
Moldova, Chisinau	OPEN	138.0 ms	8.8.8.8
Netherlands, Amsterdam	OPEN	6.0 ms	8.8.8.8
Netherlands, Amsterdam	OPEN	11.0 ms	8.8.8.8
Netherlands, Amsterdam	OPEN	1.0 ms	8.8.8.8
Netherlands, Amsterdam	OPEN	1.0 ms	8.8.8.8
Norway, Oslo	OPEN	43.0 ms	8.8.8.8
Poland, Warsaw	OPEN	18.0 ms	8.8.8.8
Romania, Bacău	OPEN	37.0 ms	8.8.8.8
Romania, Bucharest	OPEN	61.0 ms	8.8.8.8
Serbia, Belgrade	OPEN	178.0 ms	8.8.8.8
Russia, St Petersburg	OPEN	6.0 ms	8.8.8.8
Singapore, Singapore	OPEN	1.0 ms	8.8.8.8
Turkey, Istanbul	OPEN	9.0 ms	8.8.8.8
Taiwan, Taipei	Timeout	-	8.8.8.8
United States, Miami	OPEN	0.0 ms	8.8.8.8
United States, Dallas	OPEN	27.0 ms	8.8.8.8
United States, Kansas City	OPEN	21.0 ms	8.8.8.8
United States, Dallas	OPEN	3.0 ms	8.8.8.8
South Africa, Johannesburg	OPEN	173.0 ms	8.8.8.8