CIDR /32Private (RFC 1918)
/32 Subnet Mask (255.255.255.255) - Usable Hosts & CIDR | ipcalc.net
Everything about /32 subnets: Subnet mask 255.255.255.255, wildcard mask 0.0.0.0, 1 usable hosts, binary breakdown, and Cisco configuration templates.
Enter any notation: 192.168.1.1/24, 10.0.0.1 255.255.255.0, or plain IP
Subnet Mask Prefix: /32Netmask: 255.255.255.255
Presets:
32-Bit Subnet Boundary Visualizer
Click any bit position to adjust the CIDR prefix boundary
Network (32 bits)
Host (0 bits)
Octet 1192Mask: 255
11111111
Octet 2168Mask: 255
11111111
Octet 31Mask: 255
11111111
Octet 40Mask: 255
11111111
Usable Hosts
1
Total IPs: 1
Network Address
192.168.1.0
Prefix: /32
Usable Host Range
192.168.1.0
192.168.1.0
Broadcast Address
N/A (Host Route)
Host Route
Detailed Subnet Breakdown
Private (RFC 1918)Subnet Mask
255.255.255.255
Wildcard Mask (Cisco ACL)
0.0.0.0
Hexadecimal IP / Mask
0xC0A80100 / 0xFFFFFFFF
Integer / Decimal IP
3232235776
IP Class & Routing
Class C • Classless Inter-Domain Routing (CIDR)
Reverse DNS (in-addr.arpa)
0.1.168.192.in-addr.arpa
Cisco IOS Command Templates
ip address 192.168.1.0 255.255.255.255
access-list 1 permit 192.168.1.0 0.0.0.0
Technical Subnet Specifications
Prefix Length/32
Dotted Decimal Subnet Mask255.255.255.255
Wildcard Mask (Inverse)0.0.0.0
Total Available IP Addresses1
Usable Host Capacity1 hosts
Network Bits vs Host Bits32 Network / 0 Host
Binary Subnet Mask11111111.11111111.11111111.11111111
Cisco IOS Configuration
Copy-paste templates for Cisco router and switch interface setup:
! Configure Interface
interface GigabitEthernet0/0/1
ip address 192.168.1.0 255.255.255.255
no shutdown
! Access-Control List
access-list 10 permit 192.168.1.0 0.0.0.0
Tip: Wildcard mask is computed by inverting the subnet mask (
~mask).Typical Network Use Cases for /32
A /32 network block provides 1 total IP addresses with 1 usable host interfaces.
Designated Role: Single Host / Loopback.
Host Route Note: /32 addresses specify an exact single host interface, commonly utilized for router Loopback0 management interfaces and BGP router IDs.
Frequently Asked Questions: /32 (255.255.255.255)
Authoritative answers to common /32 subnetting, host capacity, and networking questions.
Q1What is a /32 subnet mask and how many hosts does it support?
A /32 subnet mask (255.255.255.255) designates an individual single host route. It provides exactly 1 IP address (192.168.1.0) with no broadcast or network range, commonly configured on router Loopback interfaces, VPN client tunnel endpoints, or firewall host rules.
Q2What is the subnet mask and wildcard mask for /32?
The dotted-decimal subnet mask for a /32 prefix is 255.255.255.255. The corresponding wildcard mask (used in Cisco ACLs and OSPF network statements) is 0.0.0.0. In binary, the subnet mask consists of 32 network bits (1s) followed by 0 host bits (0s).
Q3What is a /32 subnet typically used for in network design?
A /32 subnet is typically deployed for single host / loopback. In enterprise and cloud environments (such as AWS VPCs or Azure VNets), /32 allocations provide the optimal balance between host capacity and address conservation.
Q4What does /32 mean in CIDR notation?
Classless Inter-Domain Routing (CIDR) notation expresses the subnet mask as a forward slash followed by the prefix length. A /32 prefix indicates that the first 32 bits of the 32-bit IPv4 address are locked for network identification, leaving the remaining 0 bits available for addressing host interfaces.