Networking & IT Tools

IPv4 Address Class Identifier

Enter an IPv4 address to identify its classful network class and default subnet mask.

Class C

Default mask: 255.255.255.0 (/24)

Class C: small networks, up to 254 hosts each.

This classful addressing scheme (Class A/B/C/D/E) predates CIDR and is rarely used to route traffic today, but it's still a common reference for understanding legacy documentation and default subnet masks.

How to use this tool

  1. 1Enter an IPv4 address.
  2. 2See its classful network class (A-E) and default subnet mask.

Frequently asked questions

Is classful addressing still used today?+

Modern networks use classless (CIDR) addressing, but classful classes are still a common reference point for understanding default masks and legacy documentation.

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