Enter Network Details
Example Data Table
| IP Address | CIDR | Network | Subnet Mask | Usable Hosts |
|---|---|---|---|---|
| 192.168.1.25 | /24 | 192.168.1.0 | 255.255.255.0 | 254 |
| 10.0.5.77 | /20 | 10.0.0.0 | 255.255.240.0 | 4094 |
| 172.16.9.14 | /30 | 172.16.9.12 | 255.255.255.252 | 2 |
Formula Used
Subnet mask: CIDR bits are filled with ones. Remaining bits are zeros.
Network address: IP address AND subnet mask.
Broadcast address: Network address OR wildcard mask.
Total addresses: 2^(32 - CIDR).
Usable hosts: Total addresses minus 2, except /31 and /32 cases.
How to Use This Calculator
Enter a valid IPv4 address. Then enter the CIDR prefix. Press the calculate button. The tool shows the network address, subnet mask, wildcard mask, broadcast address, host range, and binary form. Use the CSV button for spreadsheet records. Use the PDF button for quick reports.
Understanding Binary Network Conversion
Why Binary Matters
Every IPv4 address is built from 32 binary bits. These bits are split into four octets. Each octet has eight bits. Decimal numbers make addresses readable. Binary values show how routing decisions happen. Network engineers use this view to find exact subnet limits.
Network and Host Parts
A CIDR prefix separates the network part from the host part. A /24 prefix means the first 24 bits describe the network. The remaining 8 bits describe hosts. Larger prefixes create smaller networks. Smaller prefixes create larger networks.
Subnet Mask Role
The subnet mask marks network bits with ones. It marks host bits with zeros. When the IP address is compared with the mask, the network address appears. This process uses the binary AND operation. It is simple, fast, and reliable.
Broadcast and Range
The broadcast address is the highest address in the subnet. It is found by turning host bits into ones. Normal host ranges sit between the network and broadcast addresses. The first and last values are usually reserved. That is why usable hosts are often two fewer than total addresses.
Planning Better Subnets
This calculator helps plan clean network ranges. It can check whether an address belongs to a subnet. It can also help avoid overlapping ranges. Use it before assigning servers, routers, printers, cameras, or office devices.
Practical Use
Binary subnet checks are useful for troubleshooting. They help explain gateway errors. They also help confirm firewall rules. Clear subnet planning reduces routing mistakes and saves support time.
FAQs
What does this calculator find?
It finds the network address, subnet mask, wildcard mask, broadcast address, host range, total addresses, usable hosts, and binary values for an IPv4 subnet.
What is CIDR?
CIDR is a prefix number like /24. It tells how many bits belong to the network part of an IP address.
Why is binary shown?
Binary shows the real bit pattern behind the address. It helps explain how masks, networks, and broadcasts are calculated.
What is a network address?
A network address identifies the start of a subnet. It is normally not assigned to a regular device.
What is a broadcast address?
A broadcast address is the last address in a subnet. It can reach all devices inside that subnet.
Why are two addresses removed?
Most IPv4 subnets reserve the first address for the network and the last address for broadcast. These are not normal hosts.
Can I use this for private networks?
Yes. It works for private and public IPv4 addresses, including 10.x.x.x, 172.16.x.x, and 192.168.x.x ranges.
Does it support IPv6?
No. This version focuses on IPv4 binary subnet calculations. IPv6 needs a different address size and formula layout.