Skip to main content

Raymii.org Logo (IEC resistor symbol)logo

Quis custodiet ipsos custodes?
Home | About | All pages | RSS Feed | Gopher

IPv4 Address Conversion Tricks

Published: 01-09-2013 | Author: Remy van Elst | Text only version of this article


Table of Contents


Theory

Did you know that http://3515693643/ is a valid link? Why? Because this is thedecimal form of the binary IP address. Normally we represent IP addresses as10.0.0.1, 4 blocks of numbers. Those numbers are actually binary octetsrepresented in decimal, therefore they can never be more than 255. If we takethe whole binary number of all blocks, and convert that to base 10, we get aresult like above, which in turn is a working network address.

If you like this article, consider sponsoring me by trying out a Digital OceanVPS. With this link you'll get $100 credit for 60 days). (referral link)

This "feature" is documented in the inet_aton(3) manpage.

I've written a little javascript based converter so you can try it out yourself.

Example

Take the IP address 209.141.58.75. As a binary octets that would be:1101000.11000110.10011101.001001011. That whole number (without the dots),converted back to decimal in turn is: 3515693643.

And, that is a working network address:

$  ping 3515693643PING 3515693643 (209.141.58.75): 56 data bytes64 bytes from 209.141.58.75: icmp_seq=0 ttl=47 time=180.208 ms64 bytes from 209.141.58.75: icmp_seq=1 ttl=47 time=197.890 ms

Example Converter

IP-JS.png

Go to the converter

Tags: articles, binary, decimal, ip, ipv4, math, network, octal