One-click convert CIDR notation to IP address ranges with subnet mask, host count, and network details
Zero Dependencies · Works Offline📝 CIDR Input
What is CIDR to IP Range Converter?
The CIDR to IP Range Converter is a free online networking tool that instantly converts CIDR notation (e.g., 192.168.1.0/24) to IP address ranges, displaying subnet mask, network address, broadcast address, and usable host count. Supports IPv4 and IPv6 with batch processing for multiple CIDRs. Perfect for network engineers, DevOps, and developers for IP address planning and subnetting. All calculations happen locally in your browser — no data is ever uploaded to a server.
Core Features
- CIDR Parsing: Automatically parses CIDR notation, calculates network address, broadcast address, IP range
- Subnet Mask: Generates corresponding subnet mask and wildcard mask
- Host Count: Precisely calculates usable hosts, handling /31 and /32 special cases
- Batch Processing: Supports multiple lines for bulk CIDR calculation
- IPv4/IPv6: Supports both IPv4 and IPv6 addresses
How to Use
1. Enter CIDR notation in the input box, e.g., 192.168.1.0/24, one per line.
2. Click "Calculate" or use Ctrl+Enter.
3. View results: IP range, subnet mask, host count, etc.
4. Click "Copy Results" or download as CSV file.
Use Cases
Network Planning
Network engineers quickly calculate subnet ranges and available hosts during IP address planning.
Firewall Configuration
DevOps convert CIDR to specific IP ranges when configuring firewall rules.
Cloud Service Configuration
Verify CIDR ranges when configuring VPCs and subnets on AWS, Azure, and other cloud platforms.
Technical Background
CIDR (Classless Inter-Domain Routing) was introduced in 1993, replacing traditional Class A/B/C network classification. CIDR uses Variable Length Subnet Masks (VLSM), formatted as IP/prefix length. The prefix length indicates the number of network bits — e.g., /24 means 24 network bits and 8 host bits. Usable hosts = 2^(32-prefix) - 2 (subtracting network and broadcast addresses), though /31 networks (point-to-point links) have 2 usable addresses and /32 has 1. RFC 4632 defines CIDR usage specifications in detail.
❓ FAQ
What is CIDR notation?
A method for IP address allocation formatted as IP/prefix length, e.g., 192.168.1.0/24 means the first 24 bits are the network portion.
Does it support IPv6?
Yes. The tool supports both IPv4 and IPv6 CIDR notation.
How is usable host count calculated?
Usable hosts = 2^(32-prefix) - 2, with special rules for /31 and /32.
Is my data uploaded?
No. All calculations happen locally in your browser.
Does it support batch conversion?
Yes. Enter multiple CIDRs, one per line.