Subnet Calculator — Calculate IP Subnets & CIDR Ranges Free
Calculate subnet mask, network address, broadcast address, and host range from any IP address and CIDR prefix. Free, instant subnet calculator.
Enter IP address with CIDR notation, e.g. 10.0.0.0/8 or 172.16.0.0/12
Frequently Asked Questions
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What is Subnet Calculator — IP Subnet & CIDR Calculator Free Online?
A subnet calculator takes an IP address and CIDR prefix (e.g., 192.168.1.0/24) and calculates the subnet mask, network address, broadcast address, first and last usable host IPs, and total number of usable hosts. Subnetting is fundamental to network administration, cloud infrastructure (AWS VPCs, Azure VNets), and firewall rule configuration.
How to Use Subnet Calculator — IP Subnet & CIDR Calculator Free Online
- 1Enter an IP address (e.g., 192.168.1.0).
- 2Enter the CIDR prefix length (e.g., 24 for /24).
- 3View the calculated subnet mask, network address, and broadcast address.
- 4Check the usable host range and total host count.
Key Features
- Subnet mask calculation
- Network and broadcast address
- First and last usable host IPs
- Total usable host count
- Supports IPv4 CIDR notation
Benefits
- Plan network segmentation for home and enterprise networks
- Configure cloud VPC and subnet ranges correctly
- Verify firewall rules cover the intended IP ranges
- Learn subnetting concepts with instant feedback
Why Use Irreva for Subnet Calculator — IP Subnet & CIDR Calculator Free Online?
Plan network segmentation for home and enterprise networks
Configure cloud VPC and subnet ranges correctly
Verify firewall rules cover the intended IP ranges
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