Subnet Highlighter — Link

Subnet Highlighter automatically scans every page and highlights all CIDR subnet masks — both IPv4 (/0–/32) and IPv6 (/0–/128). Hover over any highlighted mask to instantly see detailed network information.

IPv4 shows:
- Network & broadcast address, first/last host
- Total IPs, usable hosts, subnet mask, wildcard
- Binary mask representation
- Class (A/B/C), Private/Public (RFC1918)
- Parent network, host offset, reverse DNS zone (PTR)
- Subnets if split into /28, /29, /30

IPv6 shows:
- Network address, first/last host
- Total addresses (as power of 2)
- Type: Global Unicast, Link-local, ULA, Multicast, Loopback
- Parent network, reverse DNS zone (ip6.arpa)
- Subnets if split

IPv4 masks are highlighted in yellow, IPv6 in blue. Works on any page including wikis, monitoring dashboards, NOC tools, and RIPE/BGP looking glasses.