IPv4 Subnet Calculator

Enter any IP address with CIDR notation or subnet mask to instantly calculate network address, broadcast address, usable host range, wildcard mask, IP class, and binary representation. No external requests — all calculations run in your browser.

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── Subnet Results ──────────────────────────────
IP Address
Subnet Mask
CIDR Notation
Network Address
Broadcast Address
First Usable Host
Last Usable Host
Usable Hosts
Wildcard Mask
IP Class
IP Type
── Binary Representation ──────────────────────
IP Address
Subnet Mask
Network
Broadcast
── CIDR Quick Reference ────────────────────────────────
CIDRSubnet MaskUsable HostsWildcardCommon Use
/8255.0.0.016,777,2140.255.255.255Class A / large ISP blocks
/16255.255.0.065,5340.0.255.255Class B / enterprise LANs
/24255.255.255.02540.0.0.255Standard home / office LAN
/25255.255.255.1281260.0.0.127Split /24 in half
/26255.255.255.192620.0.0.63Small dept segment
/27255.255.255.224300.0.0.31Very small segment
/28255.255.255.240140.0.0.15Server cluster / DMZ
/29255.255.255.24860.0.0.7Point-to-point + extras
/30255.255.255.25220.0.0.3WAN point-to-point links
/31255.255.255.25420.0.0.1Unnumbered P2P (RFC 3021)
/32255.255.255.25510.0.0.0Host route / loopback
── Reserved IPv4 Address Ranges ──────────────────────
RangeCIDRPurposeRFC
10.0.0.0 – 10.255.255.255/8Private (Class A)RFC 1918
172.16.0.0 – 172.31.255.255/12Private (Class B)RFC 1918
192.168.0.0 – 192.168.255.255/16Private (Class C)RFC 1918
127.0.0.0 – 127.255.255.255/8LoopbackRFC 5735
169.254.0.0 – 169.254.255.255/16Link-Local (APIPA)RFC 3927
100.64.0.0 – 100.127.255.255/10Shared Address Space (CGNAT)RFC 6598
224.0.0.0 – 239.255.255.255/4MulticastRFC 5771
240.0.0.0 – 255.255.255.255/4Reserved / BroadcastRFC 1112