What does this tool do?
The IP Class Checker instantly identifies the traditional class (A, B, C, D, or E) of an IPv4 address you enter by examining its first octet. It is a handy reference for networking students, candidates preparing for certification exams, and administrators who need a quick check of an address.
How to use it
- Enter an address, domain or value.
- View the results instantly.
- Copy the details you need.
How IP classes are determined
The class is assigned from the value of the address's first octet: 0–127 is Class A, 128–191 is Class B, 192–223 is Class C, 224–239 is Class D for multicast, and 240–255 is Class E reserved for experimental use. The tool reads this range, shows which class the address falls into, and helps you understand that class's default network and host portions at a glance.
Telling private and public addresses apart
Alongside the class, the tool also flags whether the address belongs to the RFC 1918 private ranges (10.0.0.0/8, 172.16.0.0/12, 192.168.0.0/16) or the 127.0.0.0/8 loopback range. This lets you quickly see whether an address is a globally routable public address or a private one used only inside a local network, which is useful when planning or troubleshooting a setup.
Frequently asked questions
Are IP classes still used today?
Modern networks allocate addresses with classless routing (CIDR), so classes no longer determine routing. Even so, the A/B/C concepts are still widely taught in education and exams and remain useful for understanding address ranges.
What are Class D and Class E for?
Class D (224–239) is reserved for multicast traffic and is not assigned to a single host. Class E (240–255) is held back for experimental and future use and is not used in normal network traffic.
Does the tool check IPv6 addresses?
No. The A–E class system applies only to IPv4. IPv6 has no concept of classes; its address space is defined by prefixes instead, so this tool focuses on IPv4 addresses.
Is IP Class Checker free?
Yes. IP Class Checker and all 300+ tools on MagmaNex are completely free with no signup or account required.
Is my data safe?
Yes. Everything runs locally in your browser. The data you enter is never sent to a server, stored, or shared.
Does it work on mobile?
Yes. IP Class Checker works on phones, tablets and desktops — no app download needed.
🔒 Privacy: everything runs in your browser, your data is never sent to a server.