IP in CIDR Checker
Check whether an IPv4 address belongs to a CIDR subnet. Verify network boundaries for routing and firewall rules in your browser.
Results
Enter your values and select check membership to see the result.
Check a network boundary
Use this tool when reviewing an allowlist, a route or a firewall rule. Enter one IPv4 address and a CIDR network. Membership includes every address in the block, including its network and broadcast addresses.
A match is a mathematical address comparison. It does not confirm that a device is online, that an address is assigned, or that a firewall permits traffic. This tool accepts IPv4; use the IP utilities for IPv6 formatting.
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