CIDR Calculator – Free Online Tool
Calculate CIDR blocks, subnet masks, IP ranges, and host counts.
Network
192.168.1.0
Broadcast
192.168.1.255
Subnet Mask
255.255.255.0
First Host
192.168.1.1
Last Host
192.168.1.254
Total Hosts
254
Prefix Length
/24
Example
Input
192.168.1.0/24
Output
Subnet: 255.255.255.0 | Range: 192.168.1.1–192.168.1.254 | Hosts: 254
The /24 prefix defines a subnet with 254 usable host addresses.
How to Use CIDR Calculator
- 1
Enter CIDR
Type a CIDR block (e.g., 192.168.1.0/24).
- 2
View Details
See subnet mask, IP range, broadcast address, and host count.
- 3
Copy
Copy the results.
Common Use Cases
- ✦Planning network subnets
- ✦Calculating firewall rules
- ✦Sizing AWS VPC subnets
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https://buildutilities.com/share/cidr-calculatorFrequently Asked Questions
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