Security Tool

Subnet Calculator

Calculate subnet masks, CIDR notation, network and broadcast addresses, and usable IP ranges instantly.

IP Address

CIDR Notation

Quick Guide

Step 1: Enter an IP address (e.g., 192.168.1.0)
Step 2: Select the desired CIDR prefix (/8 to /30)
Step 3: Click Calculate to see subnet details

What is Subnet Calculator?

Subnet Calculator computes subnet masks, ranges, and CIDR notation. See also: ip-geolocation or dns-lookup.

How It Works

To use Subnet Calculator, first enter an IP address (e.g., 192.168.1.0). Then, select the desired CIDR prefix (/8 to /30). After that, click Calculate to see subnet details. The result appears instantly in your browser.

Use Cases

System administrators checking security configurations quickly
Developers validating security tokens, hashes, or headers
Security-conscious users generating strong passwords or encryption keys

Frequently Asked Questions

What is Subnet Calculator?

Subnet Calculator computes subnet masks, ranges, and CIDR notation. It runs entirely in your browser, with no sign-up and no file uploads.

How do I use Subnet Calculator?

First, enter an IP address (e.g., 192.168.1.0). Then, select the desired CIDR prefix (/8 to /30). Click Calculate to see subnet details.

Is Subnet Calculator free and private?

Yes - Subnet Calculator is completely free and requires no account. Everything runs locally in your browser, so your lookups and generated credentials never leave your device.

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