CIDR / Subnet Calculator

CIDR / Subnet Calculator lets you calculate network address, broadcast, and usable host range from a cidr block online. Open the tool, provide your input, and get the result in a few seconds. No download, no account, and no hidden costs.

IP Address

CIDR Prefix (/0–32)

Tip: pasting a full block like 192.168.1.0/24 into the IP field splits it automatically.

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Why use CIDR / Subnet Calculator?

CIDR / Subnet Calculator is a focused utility in the Security Tools category, built to do one job well: calculate network address, broadcast, and usable host range from a cidr block. There are no bloated installers, no aggressive upsells, and no confusing pricing tiers. When you use our cidr / subnet calculator tool, you get a focused experience centered on results. Calculate network address, broadcast, and usable host range from a CIDR block. The interface stays out of your way so you can complete the task and move on, whether that means shipping code, submitting a university paper, or sending a client deliverable before end of day. We keep the interface simple and the defaults sensible, with attention to keyboard and screen-reader accessibility. Bookmark this page and return whenever you need CIDR / Subnet Calculator, it will always be free.

Key benefits

100% free cidr / subnet calculator with no subscription or trial limits
Works on Windows, macOS, iOS, Android, and Linux devices
Runs in any modern browser with no plugins or extensions
Privacy-first processing, your data is not sold to advertisers
Faster than installing dedicated security tools software

Features

Clean, distraction-free interface optimized for productivity
No account creation or email verification required
Responsive layout for desktop, tablet, and mobile screens
Regular updates and reliability improvements
Part of a suite of 120+ free tools on The Tools Kit

Popular use cases

Everyday security tools tasks without installing dedicated software
Student assignments, research, and coursework support
Small business operations without expensive software licenses
Quick fixes when you are on a shared or locked-down computer

How to use CIDR / Subnet Calculator

1
Open CIDR / Subnet Calculator
Navigate to the CIDR / Subnet Calculator page on The Tools Kit using any modern web browser.
2
Provide your input
Add the file, text, or values that CIDR / Subnet Calculator needs to work with.
3
Run the tool
Click the primary action button and wait a few seconds for processing to complete.
4
Save or copy results
Download the output file or copy the result to your clipboard for immediate use.

Frequently asked questions

Is CIDR / Subnet Calculator really free?

Yes. The Tools Kit provides CIDR / Subnet Calculator at no cost. There are no paywalls or watermarks.

Do I need to create an account?

No account is required. Open the tool and start working immediately.

Is my data secure?

We process inputs to deliver results and do not permanently store your files or sensitive content.

Can I use this on mobile?

Yes. All our tools are mobile-friendly and work in Safari, Chrome, and other major mobile browsers.

Do I need to install anything?

No. CIDR / Subnet Calculator runs in your web browser, so there is nothing to download or install.

Last reviewed: July 2026

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