API & DevOps
IP Subnet Calculator
Enter an IPv4 address and CIDR prefix to compute subnet mask, network and broadcast addresses, usable host range, and host count. A basic calculator for lab and ops checks.
Runs entirely in your browser. Your data never leaves this device.
- CIDR → mask
- Network & broadcast
- Host range
- Host count
- Private in-browser
Workspace
Client-side · No upload
How it works
- Enter an IPv4 address and CIDR prefix (e.g. 24).
- Review mask, network, broadcast, and hosts.
- Copy values you need.
Key features
- CIDR → mask
- Network & broadcast
- Host range
- Host count
- Private in-browser
FAQ
IPv6?
MVP is IPv4 only.
Host count?
Usable hosts exclude network and broadcast for prefixes < 31.
Private?
Yes.
Validation?
Invalid IPs show an error instead of partial results.
Keep building
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