About Subnet Calculator
Calculate IPv4 and IPv6 subnet details instantly. Enter any IP address with CIDR notation to see network address, broadcast, usable host range, netmask, and wildcard mask. Essential tool for network administrators and developers.
How to Use
- 1Select IPv4 or IPv6 mode
- 2Enter the IP address
- 3Adjust the CIDR prefix with slider or presets
- 4View calculated network details
- 5Copy addresses as needed
Key Features
- IPv4 and IPv6 support
- CIDR notation input
- Network and broadcast addresses
- First and last usable host
- Subnet mask and wildcard mask
- IP class identification (IPv4)
- Private/public detection
- Binary representation
- IPv6 expansion and compression
Common Use Cases
Frequently Asked Questions
What is CIDR notation?
CIDR (Classless Inter-Domain Routing) uses a suffix like /24 to indicate how many bits are the network portion. /24 = 255.255.255.0 netmask.
Why are there fewer usable hosts than total IPs?
For IPv4 subnets larger than /31, the first IP is the network address and the last is broadcast, leaving 2 fewer usable host addresses.
Privacy First
All processing happens directly in your browser. Your files never leave your device and are never uploaded to any server.
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