CIDR Calculator Input
Enter CIDR notation or IP address with subnet mask
Click to load example CIDR notations
/1
/24
/32
Real-Time Features
This CIDR calculator provides 15+ advanced functionalities in real-time:
CIDR to Range
Subnet Mask
Wildcard Mask
Network Address
Broadcast Address
Usable Hosts
Binary Conversion
Hex Conversion
IP Class Detection
Network Size
First/Last IP
Subnetting Info
Previous/Next Network
CIDR Visualization
Export Results
Calculation Speed
Instant
CIDR Calculation Results
CIDR Network Visualization
Network Portion
Host Portion
Class C - Private Network
How to Use the CIDR Calculator: A Complete Guide
What is CIDR Notation?
CIDR (Classless Inter-Domain Routing) notation is a compact representation of an IP address and its associated routing prefix. It's written as an IP address, a slash ('/'), and a prefix length (e.g., 192.168.1.0/24). The prefix length indicates the number of bits used for the network portion of the address.
Key Benefits of Using Our CIDR Calculator
- Real-time Calculations: Get instant results as you type or adjust parameters
- Comprehensive Network Analysis: From subnet masks to usable host ranges
- Binary & Hexadecimal Views: See IP addresses in different formats
- Visual Network Representation: Understand network/host portions visually
- Export & Share Results: Copy all calculation results with one click
Step-by-Step Usage Guide
- Enter CIDR Notation: Type a CIDR (e.g., 10.0.0.0/8) or IP with subnet mask (e.g., 192.168.1.0 255.255.255.0)
- Adjust Subnet Bits: Use the slider to change the subnet mask bits (from /1 to /32)
- Review Results: All calculations update in real-time - network address, broadcast address, usable hosts, etc.
- Visualize Network: Check the visualization to understand network vs host portions
- Copy or Export: Use the "Copy All Results" button to save your calculations
Common CIDR Examples
| CIDR | Subnet Mask | Usable Hosts |
|---|---|---|
| 10.0.0.0/8 | 255.0.0.0 | 16,777,214 |
| 172.16.0.0/12 | 255.240.0.0 | 1,048,574 |
| 192.168.0.0/16 | 255.255.0.0 | 65,534 |
| 192.168.1.0/24 | 255.255.255.0 | 254 |
Pro Tip
For network planning, remember that each subnet requires 2 unavailable addresses: the network address (first address) and the broadcast address (last address). So a /24 network (256 total addresses) has 254 usable host addresses.