Subnet Calculator

= 42 GoCalc

Calculate network details from an IP address and CIDR notation or subnet mask.Updated 2026-03-16

Network Address
Broadcast Address
Subnet Mask
Wildcard Mask
Usable Host Range
Usable Hosts
IP Class
CIDR Notation

Common Subnets

CIDRSubnet MaskHosts

How to Use Subnet Calculator

  1. Review the step-by-step explanation
  2. Click Calculate to see the breakdown
  3. Fill in the required values above
  4. Adjust optional parameters for precision

Frequently Asked Questions

What is CIDR notation?

CIDR (Classless Inter-Domain Routing) notation uses a slash and number (e.g., /24) to indicate how many bits are used for the network portion of an IP address.

What is a wildcard mask?

A wildcard mask is the inverse of a subnet mask, used in access control lists (ACLs). It's calculated by subtracting each octet of the subnet mask from 255.

Is my data safe?

Yes. All calculations happen in your browser. No data is sent to any server.

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