CIDR Calculator

A CIDR describes an IPv4 network range. The CIDR Calculator computes everything you need from a single CIDR - network address, netmask, wildcard mask, broadcast address, first and last usable host, and total/usable address counts.

It is handy when writing NetworkPolicy ipBlock rules or sizing Service/ Pod CIDRs. All calculation runs locally with no dependencies and no network calls.

The input is validated: a valid IPv4 address plus a 0-32 prefix. Problems are reported in a clear panel. Everything runs locally and nothing is uploaded.

• Full network info - network, netmask, wildcard, broadcast.
• Host range - first/last usable host.
• Counts - total and usable addresses.
• Binary view - network and netmask in binary.
• Validation - IPv4 + 0-32 prefix checked.
• Copy / Download / Print - take the table anywhere.

1. Enter a CIDR like 10.0.0.0/24.
2. Compute and read the table.
3. Copy or download the result.

Example 1 - /24. 10.0.0.0/24 -> 256 addresses, 254 usable.

Example 2 - /16. 192.168.0.0/16 -> 65536 addresses.

Example 3 - /32. 10.1.1.1/32 -> single host.

• Accurate - correct network math.
• Private - all in the browser.
• Useful - for NetworkPolicy CIDRs.
• Clear output - table with binary.
• Validated - bad input rejected.
• Copy, download or print - take it anywhere.