A subnet (or subnetwork) is a logical subdivision of an IP network. The process of dividing a network into smaller networks is called subnetting, which is used to improve performance and security.

Subnet Calculator - IP & CIDR Network Tool

Q: What is the difference between a Network and Broadcast address?

The Network Address is the first IP in a subnet and identifies the network itself. The Broadcast Address is the last IP and is used to send messages to all devices on that network. Neither can be assigned to a specific device.

Q: What is a Wildcard Mask?

A wildcard mask is an inverted subnet mask used in some networking equipment (like Cisco routers) for access control lists (ACLs) to specify which parts of an IP address to match.

Q: Is the data I enter in this tool kept private?

Yes, your data is 100% private. All calculations are processed entirely within your web browser. No information is ever sent to our servers.

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Subnet Calculator

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Network Details

IP Address

Subnet Mask

/1 /32

Calculated Results

Network Address -

Broadcast Address -

Usable Host Range -

Total Hosts -

Subnet Mask -

Wildcard Mask -

IP Class -

IP Type -

About the Subnet Calculator

Our Subnet Calculator is a free online tool designed for network administrators, developers, and students to quickly work out the details of an IP network. Subnetting can be a complex and error-prone task, so we built this tool to make it fast and easy. You can enter an IP address and a subnet mask, and the calculator will instantly provide all the essential information about that network.

This tool shows you everything from the network and broadcast addresses to the range of usable IPs for your devices. It's a great way to plan your network layout, troubleshoot configuration issues, or simply learn how subnetting works. The calculations are all done in your browser, so it's fast, and your data is completely private.

How to Use the Tool

Enter an IP Address: Type the IP address you want to analyze into the "IP Address" field.
Select a Subnet Mask: You can adjust the subnet mask in two ways: move the slider or select a CIDR notation (e.g., `/24`) from the dropdown menu.
View the Results: The tool will instantly update the "Calculated Results" panel with all the information about your network, such as the network address, usable host range, and total number of hosts.

Frequently Asked Questions

What is a subnet?

A subnet (or subnetwork) is a logical subdivision of an IP network. The process of dividing a network into two or more smaller networks is called subnetting. It's used to improve performance and security by isolating network traffic and making the network more manageable.

What is CIDR notation?

CIDR (Classless Inter-Domain Routing) notation is a compact way to represent a subnet mask. It's the slash followed by a number (e.g., `/24`) that you often see after an IP address. The number indicates how many bits of the IP address are part of the network portion, which defines the size of the subnet.

What is the difference between a Network and Broadcast address?

The Network Address is the very first IP in a subnet, and it's used to identify the network itself. The Broadcast Address is the very last IP, and it's used to send messages to all devices on that network at once. Neither of these two addresses can be assigned to an individual device, which is why they are not included in the "Usable Host Range."

What is a Wildcard Mask?

A wildcard mask is essentially an inverted subnet mask. It is used in some networking equipment, particularly Cisco routers, for access control lists (ACLs). It tells the device which parts of an IP address to match. Our calculator provides this value for convenience when configuring such devices.

Is the data I enter in this tool kept private?

Yes, your data is 100% private. All IP addresses and calculations are processed entirely within your web browser using JavaScript. No information is ever sent to our servers, ensuring your network information remains completely confidential.