IP Subnet Calculator

IP subnet searches are handled by the Subnet Calculator, which converts IPv4 CIDR notation into network, broadcast, mask, wildcard, and usable host range.

All tools
IP Subnet Calculator is available as the Subnet Calculator.

This is the same working tool under a different name. Keeping one main version means the formula, examples, FAQs, and guide link do not split into two slightly different pages.

Open Subnet Calculator
Inputs explained Result checks Example values Runs in your browser
IPv4 subnet192.168.1.0/24

192.168.1.10/24

Subnet mask
255.255.255.0
Wildcard mask
0.0.0.255
Broadcast
192.168.1.255
Usable range
192.168.1.1 - 192.168.1.254
Usable addresses
254

Formula steps

  1. Convert the IPv4 address and CIDR prefix into 32-bit values.
  2. Build the subnet mask from the prefix length.
  3. Use bitwise network and wildcard math to find network, broadcast, and usable range.

How to use the Subnet Calculator

  1. Enter the requested dates, times, grades, dimensions, network values, password options, or units.
  2. Check the assumptions shown on the page, especially school scales, payroll rules, concrete waste, subnet type, or security handling.
  3. Press the calculate button to see the answer, supporting metrics, and formula steps.
  4. Use examples, recent answers, or copy the result while keeping the estimate limits in mind.

What people use it for

Find the network and broadcast address for an IPv4 CIDR block.

Convert a prefix length such as /24 into a dotted decimal subnet mask.

Check usable host range and address count.

Practice subnetting for networking, security, or developer work.

Quick examples

Home LAN

192.168.1.10/24

Network 192.168.1.0, usable 192.168.1.1-192.168.1.254

Small subnet

10.0.5.17/28

16 total addresses

Point-to-point

172.16.0.8/31

2 usable /31 addresses

Need the guide or a nearby tool?

Need a slower walkthrough, a related calculator, or the full library? These links keep you close to the task you started.

Frequently asked questions

Plain-language answers about when to use the tool, what it does with your inputs, what to double-check, and how privacy works.

When should I use the Subnet Calculator?

Use it when your task matches one of these common needs: Find the network and broadcast address for an IPv4 CIDR block. Convert a prefix length such as /24 into a dotted decimal subnet mask. It works best when you already know the text, code, URL, mode, format, or technical setting the page asks for.

What is the Subnet Calculator doing with my inputs?

In plain language: The calculator converts IPv4 octets to a 32-bit number, builds the CIDR subnet mask, then uses bitwise network and wildcard math. The examples on the page are there so you can compare your inputs with a filled-out example before copying the answer.

What do the main Subnet Calculator inputs mean?

The main inputs are usually text, code, a URL, a number base, or a mode setting. Paste only the part you want the tool to work on and compare the output with the examples.

How should I read the Subnet Calculator answer?

Read the output next to your original input. If the tool changes format, units, encoding, spacing, or capitalization, compare a small sample before copying the whole result into another app.

What should I double-check before trusting the answer?

This tool covers IPv4 CIDR math. It does not configure routers, validate a live network, or handle IPv6 subnets. Also check the selected mode, input format, encoding, and whether the text includes private keys, passwords, or sensitive data.

Does the site save what I enter?

No. The tool runs in your browser tab. Your recent answers stay only on the page while you use it, and they are not sent to a server.

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