Network Address Calculator: Subnet & IP Planning Tool

April 26, 2026

🌐 Network Address Calculator

Calculate subnets, host ranges, broadcast addresses, CIDR blocks & IP segmentation for any network

⚡ Quick Presets
🔧 Calculator Inputs
✅ Calculation Results
📋 CIDR Quick Reference
/24
Most Common LAN
254
Hosts per /24
/30
P2P Links
16M+
Hosts in /8
/64
IPv6 LAN Block
3
RFC 1918 Ranges
/32
Single Host Route
4.29B
Total IPv4 Space
📐 IPv4 CIDR Subnet Table
CIDR Subnet Mask Total Addresses Usable Hosts Typical Use Case
/8255.0.0.016,777,21616,777,214Large enterprise / ISP block
/16255.255.0.065,53665,534Campus or large branch
/20255.255.240.04,0964,094Cloud VPC, data center VLAN
/22255.255.252.01,0241,022Proxmox cluster, large VLAN
/23255.255.254.0512510Medium-large office
/24255.255.255.0256254Home LAN, standard office
/25255.255.255.128128126Half-subnet, DMZ
/26255.255.255.1926462Guest WiFi, IoT
/27255.255.255.2243230Small team VLAN
/28255.255.255.2401614IoT segment, small VLAN
/29255.255.255.24886Management VLAN
/30255.255.255.25242Point-to-point links
/31255.255.255.25422*P2P (RFC 3021)
/32255.255.255.25511Host route / loopback
🔒 RFC 1918 Private Address Ranges
Range CIDR Block Total IPs Common Use
10.0.0.0 – 10.255.255.25510.0.0.0/816,777,216Enterprise / data center
172.16.0.0 – 172.31.255.255172.16.0.0/121,048,576Branch offices, cloud VPCs
192.168.0.0 – 192.168.255.255192.168.0.0/1665,536Home / SOHO networks
169.254.0.0/16APIPA65,536Auto-assigned (no DHCP)
127.0.0.0/8Loopback16,777,216Local host testing
📡 Network Standards & Addressing Reference
Standard / Protocol Value / Range Notes
IPv4 Address Space0.0.0.0 – 255.255.255.25532-bit, ~4.29 billion addresses
IPv6 Address Space128-bit340 undecillion addresses
VLSM (RFC 1878)Variable Length Subnet MaskEfficient IP allocation
CIDR (RFC 4632)Classless Inter-Domain RoutingReplaces classful A/B/C
Default GatewayUsually .1 or .254First or last usable host
Broadcast AddressLast IP in blockNot assignable to hosts
Network AddressFirst IP in blockNot assignable to hosts
Usable Hosts Formula2^(32-prefix) - 2Subtract network + broadcast
Subnet Count Formula2^(new bits borrowed)Bits borrowed from host portion
📋 Common Network Project Sizing
Scenario Recommended CIDR Usable Hosts Growth Headroom
Home Lab (1-10 devices)/28144 spare after 10 devices
Home Network (10-50 devices)/24254200+ spare after 50 devices
Small Office (50-100 devices)/24 or /23254 / 510Comfortable growth
Medium Business (100-500 devices)/221,022500+ spare capacity
Proxmox 3-Node Cluster/24 management + /22 VM254 + 1,022VMs on /22, mgmt on /24
IoT Segment/26 or /2762 / 30Isolated from main LAN
Point-to-Point Uplink/302Exactly 2 usable IPs
Cloud VPC (AWS/GCP)/16 VPC, /24 subnets65,534 / 251*AWS reserves 5 IPs per subnet
💡 Tip: Always plan for growth. Use the 20% overhead setting — if you need 50 hosts today, your block should support at least 60. A /26 (62 hosts) fits 50 devices with only 12 spare. Upgrading to a /25 (126 hosts) gives much better long-term flexibility at no extra cost since IP space is free on private networks.
💡 Tip: Isolate network segments with VLANs + separate subnets. Assign IoT, guest WiFi, and management devices to separate /26 or /28 subnets. This limits broadcast domains, improves security, and makes firewall rules simpler. Use the CIDR table above to match each segment size to a right-sized block rather than dumping everything on one /24.

network address is a separate mark that helps to recognize a node or host in a network. This address can be physical or only logical. One wants that network addresses stay unique through the whole net, even so some nets allow to use local or own addresses, that are not necessarily unique.

On same net each device has an identical network address, that forms part of its IP-address. For instance, in IP-address 172.20.18.125 the section “172.20” show the network address. The other parts form the node address, that belongs only to one particular machine in that net.

Network Address and IP Address Basics

Imagine it similarly to a number, here are a network section and a host section, only that in IP the amount of codes in parts ranges.

IP-address stores two main parts: network address and host address. Network addresses help to locate the subnet, where sits the device. Host address show exactly what computer or device it is.

The network address simply is the starting address of net, used for calling that network part. All IP-addresses that has identical network section, belongs to one same segment.

One usually writes IP-addresses in dot-decimal form, four codes, separated by spots, for instance 192.168.123.132. Under the surface, both the IP-address and the subnet mask is 32-bit strings from ones and zeros. Dot-decimal writing helps only folks.

The mask always lays ones below and zeros up. First parts point, which bits belong to network address, while other parts show, which bits are special fore the host.

Number after slash points the prefix length. For instance, /16 show, that 16 bits form the network part and 16 bits the host address. In a subnet the network address is the first, and the broadcast address the last.

Do not assign them to devices. Like this in 192.168.1.0/24 avoid using 192.168.1.0 or 192.168.1.255 for hosts.

network address does not work as IP-address for host. It simply calls the subnet. Together with subnet mask it well helps to describe networks in tables of routing and in protocols.

NAT, or Network Address Translation, allows private IP-nets to reach the internet by changing internal private addresses to outside public addresses. Routers care about that mapping. Private IP stays internal in local net, while public IP passes through the whole internet.

DNS is a system, that turns memorable domain names into numerical addresses, so that one easily finds network resources. Domain names are marks, separated by spots, where every mark does not pass 63 signs. There are also broadcast addresses for sending messages to all devices, multicast addresses for talking in a group and anycast addresses, thatdeliver packages to the nearest in group.

Network Address Calculator: Subnet & IP Planning Tool

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