​​The Cambridge Crystallographic Data Centre (CCDC).
The CCDC websites use cookies. By continuing to browse the site you are agreeing to our use of cookies. For more details about cookies and how to manage them, see our  cookie policy.

How do I determine what my IP address is?


​Some CCDC software and services require you to give us details of your IP address (or a range of IP addresses). There are two main types of IP address information that we may require:

External IP address

This is the IP address that the outside world will see when you access a website or web service from your computer. As such, this is useful information for CCDC when you need to access services such as WebCSD. Your external IP address will often be affected by use of a firewall or proxy server.

The easiest way to determine your external IP address is to visit a website that tells you your IP address. If you run a Google search for 'what is my IP address', Google will usually tell you directly in the search results, and you should otherwise see plenty of websites listed that do this.

Local IP address

Your local IP address identifies your computer or device on your local network. Your local IP address may be used by locally installed CCDC software on your computer, such as the CSD Portfolio. In this case the software needs to know about its local environment and may not require any further internet access at all.

Your local IP address can be different to your external IP address (as detailed above), or if you have a direct connection to the internet it could be the same. Determining your local IP address is a little trickier than for your external IP address and the method varies between operating systems:


1. Click on the Start menu and type cmd and then enter.
2. A command line window will open. Type ipconfig and press enter.
3. You'll see a lot of information, but the line you want to look for is "IPv4 Address." The number across from that text is your local IP address.


1. Open a console window and type /sbin/ifconfig
2. You will see a lot of information, but the line you want to look for is "inet addr". The number next to that is your local IP address.

Alternatively type hostname -I

Mac OS X:

1. Open System Preferences (via the Apple menu at the top left hand corner of your screen).
2. When System Preferences opens, click on the icon labelled Network.
3. You should see a few options on the left with labels like Wi-Fi, Ethernet, Bluetooth, etc. The ones with green dots have IP addresses assigned to them. Click the one on top (if it isn't already selected) and look to the right. There should be a sentence that reads something like "Wi-Fi is connected to Chocolate and has the IP address XXX.XXX.XXX.XXX." The number at the end of that sentence is your local IP address. 

Providing an IP range for a large number of devices

Providing a range of external or local IP addresses can allow access for a large number of users to CCDC software and services. The details given above can provide individual IP addresses and could be used to determine a small range, but for large scale ranges we would recommend you first discuss with your systems administrators what range(s) would cover your access requirements to ensure CCDC provide the correct access for you.