I came across a tweet complaining about 24 using 2.718.281.828 as an IP address, which obviously wouldn't work. Others responded that using a non-functional IP address is like using 555 for phone numbers.

Is there an equivalent of phone number's 555 (or more specifically, 555-0100 through 555-0199 in the US) used for fictitious IP addresses in tv and movies?

  • I used "realism" as a tag, but it's more trying to avoid being real. Any suggestions?
    – Golden Cuy
    Jun 2, 2014 at 0:55
  • 3
    Actually, some commands will take ip addresses like that, and simply 'add' them together, so becomes Therefor although it may not work verbatim in all programs, it does point to a real address, namely
    – Shelvacu
    Jun 2, 2014 at 7:54
  • 3
    The thing about 555 is phone calls are intrusive. Only *4 people are ever going to check an ip address used in a movie by pinging it or whatever, so it doesn't matter if you use a real one. *That's a fact.
    – user9930
    Jun 2, 2014 at 12:19
  • 20
    Has anyone else noticed that IP is the number e?
    – CDspace
    Jun 2, 2014 at 17:43
  • 2
    Slightly unrelated but interesting is that example.net, example.org and example.com are reserved by the IANA for documentation purposes: iana.org/domains/reserved Jun 3, 2014 at 13:25

4 Answers 4


There was a follow up tweet about this:

The IP address equivalent of 555 phone numbers is actually well documented in RFC5737. e.g. is TV safe. https://www.rfc-editor.org/rfc/rfc5737#section-3

Which links to

  1. Documentation Address Blocks

The blocks (TEST-NET-1), (TEST-NET-2), and (TEST-NET-3) are provided for use in

I don't know what is commonly used in the TV or movie industry, though.

  • 1
    And we have an RFC for apparently no propose...
    – Braiam
    Jun 2, 2014 at 21:08
  • 5
    @Braiam providing a safe IP address that is known to be unused for documentation purposes has no purpose? If you want to lord it over the RFCs, it's easier to point to those published on 4/1 as being superfluous and a waste of time.
    – Nick T
    Jun 2, 2014 at 22:02
  • 1
    Don't forget the my fav website. example.com
    – Reactgular
    Jun 2, 2014 at 22:20
  • How about any address starting with 127.?
    – supercat
    Jun 2, 2014 at 23:21
  • 1
    @Braiam just because it has less purpose than RFC2324 doesn't make it useless.
    – Anthony
    Jun 3, 2014 at 3:30

It is most common to use addresses containing octets outside the possible range of 0 to 255 for a "555-1234"-esque IPv4 analog.

While using valid-looking, "approved" ranges is OK, if an actor need say them aloud they might not be that great. Plus, from the TEST-NET's Andrew mentions, .0.'s aren't cool, and .100. could appear "too ideal". If users are at all familiar with IP addresses (not uncommon nowadays) anything starting with 192.168., the most common block for consumer private networks, could break an audience's suspension of disbelief.


  • In 24 Jack gave Chloe an IP address starting with 292
  • Rizzoli and Isles traced an email message back to an IP address like ""
  • The Net featuring Sandra Bullock
  • Person of Interest chat sessions and more below


  • That first image is actually from a Person of Interest episode called "Root Cause", that whole show is about a hacker and ex-CIA agent and it's also full of fake IPs. Jun 2, 2014 at 21:51
  • 3
    Seeing something bigger than 255 seriously breaks suspension of disbelief though.
    – ithisa
    Jun 3, 2014 at 2:43
  • "UN*X" is now officially an operating system! (Or maybe they didn't want to use a trademark, just like the rest of us)
    – Golden Cuy
    Jun 3, 2014 at 5:08
  • @AndrewGrimm they probably didn't want to pay SCO licensing fees :P
    – Nick T
    Jun 3, 2014 at 5:55
  • Somehow I don't think that "port 42" was an accident... Jan 25, 2016 at 4:02

Well, you could use ones that are firewall-based, like 192.168.xxx.xxx or 10.1.x.x... those ones are fine because they are internal, and are based on router setups (it'd only connect people to a router on their own network).

Or, assuming we are still talking IPv4 only (I have no idea what you'd do for IPv6 as I'm totally unfamiliar with its format, though it's probably simple math), just break out the rules and use any number beyond 255. Since all IP addresses have to contain 4 numbers less than 2^8 (8 bits of 0 or 1, in case you were wondering what that root is. It's the number of combinations you can get with 8 bits), use something like 300.129.231.56.

I'd guess you probably already know that based on your initial question, so if that's the case, I'd use a firewall-reserved one like 192.168.x.x or 10.1.x.x. There probably are other reserved ones, I just don't know them.

  • Unfortunately, some programs resolve invalid IP addresses to valid IP addresses as mentioned in the comments of the question. Jun 2, 2014 at 16:31
  • You're not wrong, but it's still technically misuse, even if it's not a problem. The TEST-NET IPs mentioned in Andrew Grimm's answer were created for exactly these situations. Jun 2, 2014 at 19:21

Adding to the answer by @Andrew: For IPv6 it's 2001:DB8::/32 according to RFC 3849.

You must log in to answer this question.

Not the answer you're looking for? Browse other questions tagged .