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Toolspire

Internet & Network Tools

Port Number Lookup

Port Number Lookup is part of Toolspire and is ready as soon as this page loads. 443 is HTTPS on TCP. 22 is SSH. 53 is DNS on TCP and UDP. The list is the common services people ask about. A number that is missing was not probed; it is just not in the list.

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On this page

What you can do here

Number or name

443 returns one row. Typing mysql returns 3306. A partial name can return several rows, listed in the detail.

Protocol on the row

DHCP is labelled UDP. HTTPS is labelled TCP. DNS is labelled TCP/UDP because both are real.

A short note, not a scan

Each row says what the port is for. The page never sends a packet to an address you did not type, and there is no address box.

The sequence

How to use the Port Number Lookup

  1. 1

    Type the number or the service

    Use 443, or https, or ssh. The match is the list on this page, not a live host.

  2. 2

    Read the protocol

    A firewall rule that says TCP 53 does not cover ordinary DNS queries, which are UDP. The row says which one the service usually uses.

  3. 3

    Treat a miss as “not in the list”

    Thousands of registered ports are absent. Absence is not a closed port and not an unused port.

Worth knowing

  • Port Number Lookup on Toolspire: 443 TCP is HTTPS. That is the port a browser uses for a site with TLS.
  • 22 TCP is SSH, including SFTP and Git over SSH. 53 is DNS, usually UDP, and TCP when the answer is large.
  • Mail is split on purpose: 25 is server-to-server SMTP, 587 is submission from a mail app, 465 is SMTPS.
  • The list is fixed. Nothing is contacted, and port 1 returning no row does not mean a host has that port closed.

A pocket list, not a port scan

People search a port because a log, a firewall rule or an error named a number. The useful answer is the service name and whether it is TCP, UDP or both. This page answers from a short list of those well-known services: the web, mail, DNS, SSH, databases and a few admin ports. It does not contact an IP address, it does not discover what is listening, and it does not suggest how to reach a service you do not administer. Redis on 6379 and MongoDB on 27017 are included with the note that they should not face the public internet.

FAQ

Questions about Port Number Lookup

Where does Port Number Lookup run?

Port Number Lookup runs in this tab on Toolspire. What you type or drop in is not sent to us and is not stored on a server.

What is port 443?

HTTPS on TCP. It is HTTP inside TLS, the port a browser uses for a secure site.

What is port 22?

SSH on TCP. File transfer with SFTP and Git over SSH use it too.

Why are there three SMTP ports?

Port 25 is how mail servers hand mail to each other. Port 587 is how a person’s mail app submits a message. Port 465 is SMTP wrapped in TLS from the start. They are not interchangeable.

Does a missing port mean it is closed?

No. The page did not look at a computer. The number is simply not one of the named rows.

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