Windows XP or Windows 2000
Run the command prompt (usually under Start > Run)
In the Run window field, type cmd
Type ipconfig /all
Macintosh OS X
Open the System Preferences application.
Click the Network icon
In the Show: drop down, select Network Status
Look for the Built-in Ethernet item, or other applicable network interface
The IP address is shown next in the area to the right
Macintosh OS 9
The following will always work for fixed-IP-address machines (i.e., ethernet or "premium" dialup); they will work for normal "dynamically-assigned IP address" dialup machines only while the connection is running.
(Shortcut) If you are using NCSA Telnet:
Choose Show Network Numbers from the Network menu, OR
When you type a command requiring your IP address, press command-I (or choose Send IP number from the Network menu) instead of typing the number-- it will be typed for you.
If your Mac uses MacTCP
MacTCP will show up in the Control Panels
Open it -- the IP address is displayed there, labeled as such.
If your Mac uses Open Transport
TCP/IP will show up in the Control Panels
Open it -- the IP address is displayed there, labeled as such.
Windows 98/ME
Press Start
Choose Run
Type winipcfg
Unix
In a terminal window, use the command
ifconfig -a
or, if not found,
/usr/sbin/ifconfig -a
You may get a variety of responses back. The one you're looking for is one that includes the words "BROADCAST" and "inet," where "inet" introduces the IP address -- e.g.,
le0: flags=<863UP,BROADCAST,NOTRAILERS,RUNNING,MULTICAST> mtu 1500 inet 128.8.10.95 netmask ffffff00 broadcast 128.8.10.255
Using the Web
Here is a webpage provided by Networking and Telecommunications Services that will tell you your hostname and IP address: http://noc.net.umd.edu/cgi-bin/netmgr/whoami
