Ports·1883
1883
mqtt
TCP · 0x075B

Port 1883 — mqtt

Messaging

Port 1883 carries MQTT messaging over TCP. Above 1023, so an ordinary user can open it. Its encrypted twin is 8883.

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
MQTT messaging (mqtt)
Kind
Messaging
Protocol
TCP
Range
Registered
Root needed
No
Hexadecimal
0x075B
Binary
0000011101011011
Two bytes
7 · 91
Encrypted twin
8883

Same kind

Passing messages along, or queueing them 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 1883 used for?

MQTT messaging (mqtt) uses it, over TCP.

Q. Does opening port 1883 need root?

No. It is above 1023, so an ordinary user can open it.

Q. Which range does port 1883 fall in?

Registered (1024–49151). In hex it is 0x075B.

Q. Is there an encrypted version of port 1883?

Port 8883 does the same thing wrapped in TLS.