Calculate network, broadcast, mask and usable hosts for any IPv4 CIDR.
| Network Address | 192.168.1.0 |
| Broadcast Address | 192.168.1.255 |
| Subnet Mask | 255.255.255.0 |
| CIDR Notation | /24 |
| Wildcard Mask | 0.0.0.255 |
| First Usable Host | 192.168.1.1 |
| Last Usable Host | 192.168.1.254 |
| Total Addresses | 256 |
| Usable Hosts | 254 |
| Binary Mask | 11111111.11111111.11111111.00000000 |
Was this tool helpful?
86% · 116 people found this tool helpful
Designing or auditing a network means turning CIDR notation into something you can act on: network address, broadcast, usable host range, subnet mask and total hosts. This calculator does the binary math for you. Enter an IPv4 address with a prefix length (or a mask) and you get every property you need to plan VLANs, configure firewalls, or document an environment. No data leaves the page — the calculation runs entirely in your browser.
Fill in the input fields — the subnet calculator accepts numbers, dates, or units depending on the mode.
Pick the operation or unit you want (add, subtract, percentage, convert) using the toggles above the inputs.
The answer updates instantly as you type; no need to click a "calculate" button.
Copy the result to your clipboard or take a screenshot for reports, invoices, or homework.
Doing this calculation by hand every time is a waste of your attention. Subnet Calculator keeps the math boring and correct so you can focus on the decision it feeds into. The formulas are transparent, the inputs are forgiving, and every result is deterministic — the same inputs always produce the same answer, which matters when you need to defend a number to a client or a manager. Toolzer's design philosophy is simple: privacy-first (no tracking, no accounts), performance-first (the page is interactive in under a second on a 3G connection), and honesty-first (no fake ratings, no dark patterns, no upsells). Subnet Calculator follows the same rules as every other utility on the site. You can bookmark this page, share the URL with a colleague, or pin it to your browser's toolbar — the experience will be identical every visit, and it will keep working even if you're on airplane Wi-Fi. Real people use this tool for real work — freelancers cleaning up client deliverables, sysadmins triaging tickets, students finishing assignments — and it is tuned for those workflows, not for demo videos.
The first 24 bits are the network, leaving 8 bits for hosts — 256 addresses total, 254 usable after reserving network and broadcast.
The first is the network identifier, the last is the broadcast address. Neither can be assigned to a host on IPv4 networks.
Yes — RFC 3021 allows /31 for point-to-point links and uses both addresses for hosts. Most modern routers support it.
Pick non-overlapping private ranges per environment (10.x for prod, 192.168.x for lab, 172.16.x for VPN), and document every allocation.
No. Every utility on Toolzer is free, anonymous, and works in any modern browser without registration.
Yes. Whenever the tool can produce an answer entirely in the browser, the data never leaves your device.
Yes. The interface is fully responsive and works on iOS Safari, Android Chrome, and every modern mobile browser.
Yes. Every Toolzer page has a clean permanent URL you can bookmark or share.
Your public IP address is the unique number your internet provider assigns to your connection so servers kn…
IP geolocation maps an IPv4 or IPv6 address to a country, region, city, ISP and ASN using public WHOIS plus…
DNS lookup is how every domain on the internet turns into the IP address your browser actually connects to.
Ping measures how long a small network packet takes to reach a host and come back.
Every network card on earth carries a 48-bit MAC address whose first half identifies the manufacturer throu…