Subnet Calculator
Enter a base network and the number of subnets you need. The calculator finds the smallest prefix that fits and lists every subnet with its network address, broadcast, and host range.
100% client-side · no upload
| # | Network | First host | Last host | Broadcast |
|---|
How to use
- Enter your base network in CIDR notation, e.g.
192.168.0.0/22. - Enter how many subnets you need (e.g. 4).
- Click Calculate subnets to see the subnet list with all address details.
Related network tools
- IP / CIDR Calculator — get full details for a single CIDR range
- Ping Output Explainer — decode RTT, TTL, and packet loss
- Port Number Lookup — find service names for TCP/UDP ports
よくある質問
- Is this subnet calculator free?
- Yes, completely free with no signup and no usage limits.
- Does my data leave my device?
- No. All subnet calculations run in JavaScript inside your browser. Nothing is sent to any server.
- Does it work on mobile?
- Yes. The tool is mobile-first and works on iPhone Safari and Android Chrome.