Plan Your Network in Seconds
Enter any IPv4 address and CIDR prefix to see the complete subnet breakdown: netmask, network address, broadcast, first and last usable host, and total host count. Essential for network design, firewall rules, and DHCP configuration.
CIDR Basics
/24 = 256 addresses (254 usable, netmask 255.255.255.0). Each lower prefix doubles the size: /23 = 512, /22 = 1024. /30 is the smallest usable subnet (2 hosts, for point-to-point links).
Reserved Addresses
Network address (all-zero host) and broadcast (all-ones host) aren't assignable. So /24 gives you 254 usable addresses, not 256. /31 is a special case for point-to-point (RFC 3021).
FAQ
Does it support IPv6?
Not yet. IPv6 prefix lengths work differently — we'll add an IPv6 tool soon.
Try Also
Why Use This IP Subnet Calculator?
The IP Subnet Calculator runs entirely in your browser, which means three things matter for you. First, it's instant — there's no server round-trip, no upload, no waiting on someone else's queue. Second, it's private — nothing you enter ever leaves your device, which makes it safe for sensitive numbers, draft copy, or files you don't want sitting on a third party's servers. Third, it's free forever — no signup, no email capture, no "basic vs. pro" upsell. Open the page, get the answer, close the tab.
Common Use Cases
- Everyday lookups when you need a fast, reliable answer without installing an app
- Cross-checking results from another tool or spreadsheet when accuracy matters
- Quick reference during work calls, school assignments, or planning sessions
- Sharing the link with a colleague or friend who needs the same answer
- Bookmarking for repeat tasks that come up regularly throughout the week
Privacy & How Your Data Is Handled
Every calculation and every transformation in the IP Subnet Calculator runs locally in your browser using standard JavaScript. We don't upload your input to any server, we don't log it, and we don't pass it to a third-party API. The tool works the same whether you're on a fast home connection or completely offline once the page has loaded. If you want to verify this for yourself, open your browser's network tab and run the tool — you won't see any outbound request carrying your data.
Frequently Asked Questions
Is the IP Subnet Calculator really free?
Yes. Every tool on ClickSolveTools is free with no signup, no email capture, no paywalled "pro" features, and no usage limits. We don't sell your data and we don't run ads inside the tool itself.
Does the IP Subnet Calculator work on my phone?
Yes. The IP Subnet Calculator is mobile-first and works in any modern browser on iOS, Android, Windows, Mac, Linux, and ChromeOS. Inputs are touch-friendly, the layout is fully responsive, and nothing requires a desktop-only feature to function.
Do I need to sign up or install anything?
No. There's no account, no extension, no app to download. Open the page in any browser, use the tool, and close the tab when you're done. Your usage isn't tied to a profile.
Is my data safe?
Everything runs locally in your browser. We don't transmit your inputs, calculations, or files to any server. You can use the tool with full confidence even for sensitive information.