無料IPサブネット計算機オンライン｜Absolutool
Calculate network details from an IP address and CIDR prefix.
Quick Examples
CIDR Reference Table
How to Use
- Enter an IP address (e.g., 192.168.1.0).
- Select a CIDR prefix (/0 to /32).
- Click Calculate to see network details.
- Click Copy Results to copy all values.
Frequently Asked Questions
What is CIDR notation?
CIDR (Classless Inter-Domain Routing) notation like /24 defines how many bits of the IP address identify the network. A /24 means the first 24 bits are the network part, leaving 8 bits (256 addresses) for hosts.
What is the difference between network and broadcast address?
The network address is the first address in a subnet (all host bits are 0). The broadcast address is the last (all host bits are 1). Neither can be assigned to a host.
Does this support IPv6?
This tool currently supports IPv4 subnetting only. IPv6 subnet calculation may be added in a future update.