Protocol Overview
IPv4 uses a 32-bit address space, enabling ~4.3 billion unique identifiers. It operates at the Network Layer (Layer 3) of the OSI model.
32-bit
Address Size
4.29B
Max Addresses
4 Octets
Format
0–255
Octet Range
Structure: Network ID · Subnet ID · Host ID
IP Address Classes
IPv4 is divided into 5 classes based on the leading bits of the first octet.
| Class | Range | Default Mask | Use |
|---|---|---|---|
| A | 1 – 126 | /8 | Large Networks |
| B | 128 – 191 | /16 | Medium Networks |
| C | 192 – 223 | /24 | Small Networks |
| D | 224 – 239 | — | Multicast |
| E | 240 – 255 | — | Experimental |
Syntax Validator
Validates IPv4 format and identifies its class and type.
Status
Class
Type
Default Mask
Mask Calculator
Enter a CIDR prefix to get full mask details.
Subnet Mask
Wildcard Mask
Total Addresses
Usable Hosts
Network Bits
Host Bits
Binary Block Solver
Computes the full subnet range from a base IP and prefix.
Network Address
First Usable Host
Last Usable Host
Broadcast Address
Total Addresses
Usable Hosts
Subnet Mask
Live Binary Translator
Real-time decimal → binary conversion. Enter IP + prefix to see network bits vs host bits.
Network Bits
Host Bits
00000000
0
00000000
0
00000000
0
00000000
0
ISP Address Allocation Planner
Allocates sequential subnets to customer groups starting from a base network.