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CIDR Calculator

Use the CIDR calculator to convert an IP address and prefix into the network range, subnet mask, and usable host count.

⌘ Runs in browser ◴ No data stored ⌁ Free
IPv4 CIDR or range input
CIDR calculation result

How to use

  1. 1 Enter an IP address with a CIDR prefix length.
  2. 2 Calculate the network address, broadcast address, subnet mask, and host range.
  3. 3 Copy the range details you need for network or cloud configuration.

Common use cases

  • CIDR calculator for 10.0.0.0/16
  • IP address to CIDR range check
  • Subnet mask and usable host calculation

Frequently asked questions

What input formats does the CIDR calculator support?

It supports IPv4 CIDR such as 192.168.1.0/24, IP + subnet mask such as 192.168.1.1 255.255.255.0, IP ranges such as 192.168.1.10 - 192.168.1.20, and mask-only inputs such as /24 or 255.255.255.0.

What results can I check?

You can view the network address, broadcast address, first and last host, total addresses, usable hosts, subnet mask, wildcard mask, IP class, and whether the address is private or reserved.

Does it calculate IPv6?

No. The current calculation logic targets IPv4 addresses and prefixes from 0 to 32.

Related workflow

CIDR CalculatorCalculate the network range first for firewall rules or allowlists. → Chmod CalculatorWhen network restrictions go with deployed files, confirm the permission mode as well. → Htpasswd GeneratorIf IP rules are not enough, prepare a server-compatible htpasswd entry for an added auth layer.