CIDR / 子网计算器

输入一个CIDR块来计算子网详情，包括网络地址、广播地址、可用范围和子网掩码。所有处理均在您的浏览器中完成。

CIDR Notation

Common Subnets

About CIDR / Subnet Calculator

CIDR (Classless Inter-Domain Routing) notation combines an IP address with a prefix length to define a network. This tool calculates all subnet details from a CIDR block. All processing runs in your browser.

Network Address: The first address in the subnet, identifies the network itself.
Broadcast Address: The last address in the subnet, used for broadcasting to all hosts.
Usable Range: Addresses available for host assignment (excludes network and broadcast).
Subnet Mask: Determines which bits identify the network vs. host portion.