5353
mdns
UDP · 0x14E9
Port 5353 — mdns
Name lookup
Port 5353 carries Multicast DNS over UDP. Above 1023, so an ordinary user can open it.
1024–49151. Meant to be applied for, though some numbers here are custom by habit.
Where it sits in 65535
A port number is 16 bits, so it stops at 65535. The narrow band at the left is everything up to 1023.
065535
- Service
- Multicast DNS (mdns)
- Kind
- Name lookup
- Protocol
- UDP
- Range
- Registered
- Root needed
- No
- Hexadecimal
- 0x14E9
- Binary
- 0001010011101001
- Two bytes
- 20 · 233
Same kind
Turning names into addresses, or looking people and machines up.
Ports next to it
How to read this
- A port number is 16 bits, so it runs 0 to 65535. There is no port 65536.
- Opening anything at or below 1023 needs root on Unix.
- Plain and encrypted often live on different numbers — 80 and 443, for one.
- Numbers like 3000 and 8080 were never registered; those are marked as custom.
Frequently asked questions
Q. What is port 5353 used for?
Multicast DNS (mdns) uses it, over UDP.
Q. Does opening port 5353 need root?
No. It is above 1023, so an ordinary user can open it.
Q. Which range does port 5353 fall in?
Registered (1024–49151). In hex it is 0x14E9.
Q. Does port 5353 have a twin?
Not a separate one. It either was encrypted from the start or negotiates TLS on the same number.