IP Class Checker
Enter an IP address to check its A–E class, whether it is private or public, and special uses such as loopback, link-local, and multicast. All calculations happen inside your browser.
Enter an IP address to see the result.
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IP class
-Type
-Class default mask
How to use
- Enter the IP address to check.
- The class (A–E) and private/public/special use are determined automatically.
- You can also check the default subnet mask for each class.
Frequently asked questions
What is the difference between a private and public IP?
Private IPs are used only inside internal networks — the 10.x, 172.16–31.x, and 192.168.x ranges. Public IPs are uniquely identified on the internet.
How are IP classes divided?
By the first octet: A (1–126), B (128–191), C (192–223), D (224–239, multicast), E (240–255, reserved). 127 is loopback.
Are the values I enter sent to a server?
No. All calculations happen only inside your browser, and the values you enter are never sent to or stored on any server.