CIDR Calculator
Calculate CIDR subnet masks, usable IP ranges, broadcast IPs, and total host counts.
Runs entirely in your browser - your files are never uploaded
What is CIDR Calculator?
CIDR Calculator is a free, web-based utility designed for instant, local network tools tasks. It allows users to compute, format, convert, or edit data directly in their browser without installing software or registering an account.
- 100% Free & Unlimited Usage
- 0% File Uploads (100% Client-Side Privacy)
- Instant Real-Time Calculations
- Mobile, Tablet & Desktop Compatible
How to use CIDR Calculator
Select or Enter Input
Provide your source file or type your values into CIDR Calculator.
Configure Settings
Adjust parameters, formatting options, or units in real-time.
Get Instant Output
Download the final processed file or copy the generated output.
About the CIDR Calculator
The CIDR Calculator computes network address parameters from any IPv4 address and CIDR prefix length (e.g. 192.168.1.0/24 or 10.0.0.0/16).
Get complete breakdowns of subnet masks, wildcard masks, first/last usable IP addresses, broadcast addresses, total host capacity, IP class, and binary representations.
Frequently asked questions
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