what is a subnet mask

What is a Subnet Mask?

Note: Before we dive into what a subnet mask is and how it works, know that the subject can be technical and involve jargon that is hard to digest.

What is a Subnet?

Millions of networks operate on the web, and each network varies in size. The more extensive a network is, the more difficult it is to administer and ensure that it operates smoothly. The smaller a network, the easier it is to manage and maintain the network.

A network that is small, meaning it is separated into smaller pieces, those individual pieces are known as subnets. In other words, a subnet is a name given to a small network.

Why subnet a network?

Subnetting has several advantages, such as:

  • The entire network is relatively easier to manage and maintain.
  • You have control over your network.
  • You can employ the latest network security to the subnet.
  • The overall network traffic on the subnet is relatively low, meaning reduced network congestion.
  • A smaller network has improved network performance and speed.
  • By subnetting a network, you no longer require extra IP addresses from ISPs.

Although the benefits of subnetting a network are remarkable, a subnet tends to require additional hardware. This is because you’re essentially dividing the network into several pieces, and you’ll need extra resources such as routers, which will increase the cost of the entire process.

What is a Subnet Mask?

A subnet mask is a number that outlines a range of IP addresses that are available within a given network. An IP address consists of 32 binary bit numbers (4×8). That’s a long number that can get complex for many. Hence, a dot-decimal system is used to easily understand and make use of IP addresses.

An IP address is divided into two addresses – a network address and a host address. If you’re wondering what your IP is, head over to the page.

A single subnet mask bounds the number of acceptable IPs for a specific network. Several subnet masks can organize a single network into smaller networks (called subnetworks or subnets).

A subnet mask is similar to an IP address, but it’s used for internal network communication. Devices within the same subnet can conveniently communicate directly with each other, while devices on different subnets will need to communicate with the help of a router.

Here’s an example of a subnet mask: = 11000000.10101000.01111011.10000100

The subnet mask indicates the network share of the IP address. This means the subnet mask could look something like this: = 11111111.11111111.11111111.00000000

The information above can be technical, but you’re probably a technical person, which is why you’re here. Keep in mind that the IP address will change if you’re using a VPN service. To better understand the answer to the question what is a VPN? head over to the page.

Classes of IP Addresses

An Internet Protocol address is divided into three classes:

Class A, Class B, and Class C. Although two other classes exist (Class D and Class E), they are not utilized by internet users. Classes (A, B & C) each have their own default subnet mask.

Class A IP address

Class A networks use a subnet mask of and have 0-127 as their first octet. It enables 126 networks and nearly 17 million hosts per network.

Class B IP address

Class B uses a subnet mask of and has 128-191 as its first octet. This class is utilized by medium and large networks and allows 16,000 networks and 65,000 hosts per network.

Class C IP address

Class C is used for local area networks (LAN) and allows 2 million networks with 254 hosts each. Class C uses a subnet mask of and has 192-223 as its first octet.

How to Find the Subnet Mask

Finding a subnet mask is a straightforward process. Here’s how to find a subnet mask on Mac, Windows, Android, and iOS devices:

How to find a subnet mask on macOS

  • Go to System Preferences > Network
  • Select your network and click Advanced
  • Click the TCP/IP tab, and you will see your IP address and the subnet mask

How to find a subnet mask on Windows

  • Go to Control Panel > Network and Sharing Center
  • Click your network name > click Details
  • You will see the subnet mask in the details.

How to find a subnet mask on iOS

  • Go to Settings > Wi-Fi
  • Find the network you’re connected to and click the “i” icon
  • You will find the subnet mask along with other network details

How to find a subnet mask on Android

  • Go to Settings > Network & internet > WiFi
  • Select the network you’re currently connected to
  • Select Advanced and scroll down to the Network Details
  • You will find the subnet mask along with other network details

What is a Subnet Mask Calculator?

A subnet calculator enables internet users to access a range of information such as a subnet mask, the network addresses associated, the IP class, host ranges that can be utilized, and so much more. Here’s on overview:

  • You get the start and end addresses
  • You know which subnets and subnet masks are available

Similarly, an IPv4 to IPv6 converter exists that enables you to convert an IP address from IPv4 to IPv6.

Why Should You Hide Your IP Address?

Think of an IP address as your cell phone number. Having your IP address out in the open is like exposing yourself to cybercriminals. You don’t want your cell phone number to be publicly available as you’d start receiving calls and messages from unknown people.

Here are more reasons why you should hide your IP address:

  • Total anonymity when accessing geographically restricted content
  • Masks your online activities from prying eyes and your ISP
  • Ability to stay off the radar and far away from cybercriminals
  • Steer clear from third-party trackers and government surveillance
  • Online privacy and security when connecting to unsecured private and public WiFi

PureVPN’s plans come packed with exciting privacy features that mask your real IP address and encrypt your online traffic with state-of-the-art AES 256-bit encryption. The user-friendly app is compatible with nearly all devices, and you can connect up to 10 devices simultaneously.

Ather Owais Ather Owais is a tech and cybersecurity enthusiast. He is a strong advocate for online privacy and security, following technological trends and their impact on today's digital era.

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