📖 What is this tool?
CIDR Calculator computes network addresses, broadcast addresses, subnet masks, wildcard masks and usable host counts from any CIDR notation input like 192.168.1.0/24. Essential for network engineers, DevOps and cloud infrastructure planning.
💡 Example
Output
Network: 192.168.1.0
Broadcast: 192.168.1.255
Subnet Mask: 255.255.255.0
Usable Hosts: 254
🛠️ Common Use Cases
- Calculate subnet ranges for network planning
- Configure VPC CIDR blocks in AWS or GCP
- Determine how many hosts fit in a subnet
- Verify firewall rule IP ranges
- Plan IP address allocation for data centers
❓ Frequently Asked Questions
What does /24 mean in CIDR notation? ▾
/24 means 24 bits are used for the network portion, leaving 8 bits for hosts. This gives 2^8 = 256 addresses, with 254 usable hosts (excluding network and broadcast addresses).
What is the difference between /16 and /24? ▾
A /16 network has 65,536 addresses (65,534 usable), while /24 has 256 (254 usable). The smaller the prefix number, the larger the network.
What is a wildcard mask? ▾
A wildcard mask is the inverse of a subnet mask. It's used in access control lists (ACLs) and routing protocols like OSPF to specify which bits to match.
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