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IP Subnet Calculator

Network class
IP Address
Prefix Length:
IP Address:



IP Subnet Calculator tool is a tool for calculating network values. It uses network class, IP address, and subnet mask to calculate and return a list of data regarding IPv4 and IPv6 subnets.

IP Subnet Calculator is a useful tool that can help from freshly newbies to seasoned IT pros to troubleshoot and manage their network.

An IP Subnet Calculator is a tool that may be used to compute the number of subnets in a bigger network, the number of hosts that can fit in a subnet, and the size of all the subnets.

IP calculators allow us to perform all of the calculations, such as decimal to binary conversions, without having to do so manually. IP Subnet Calculator makes dividing a network into subnets much faster and easier.

The IP Calculator tool is used for troubleshooting, configuring network addressing or designing subnets and supernets.

IPTP Networks’ IP Subnet Calculator also comes with a random IP address ready to be calculated, which is useful when teaching binary values, studying how to subnet, or passing CompTIA Network+ exam.

IPTP Networks’ IP Calculator supports both IPv4 and IPv6.

Here are the easy and simple steps to use IPTP Network’s IP calculator tool.



A step-by-step guide to use IPTP Networks’ IPv4 Subnet Calculator.

To use IPv4 Subnet Calculator:

Choose the preferred Network class, which is determined by its first bits, by clicking either three options:

  1. Class A (8 bits), B (16 bits) and C (24 bits).
  2. Select the target Subnet from the dropbox according to the Network class you chose.
  3. Enter the IP address. An example IP address is already in place and can be used immediately.

Hit the Calculate button to view the result list of all the network and IP address values.

The necessary data IPv4 Subnet Calculator needs to calculate:

IP address: IPv4 address uses a 32-bit address and can support 232 IP addresses. IPv4 has 4 groups of numbers – called octets. Each octet ranges between 0 and 255 and is separated by dots (.).

Network class: Network is divided into Class A, Class B and Class C. Class A network uses the first 8 bits of the IP address as its “network part.”, while Class B uses the first 16 bits and Class C uses the first 24 bits.

Subnet: Subnet includes two parts: The subnet mask, followed by the CIDR notation.

IPTP Networks’ IP Calculator supports both IPv4 and IPv6.

Here are the easy and simple steps to use IPTP Network’s IP calculator tool.



A step-by-step guide to use IPTP Networks’ IPv6 Subnet Calculator.

To use IPv4 Subnet Calculator:

  1. Select the target Prefix Length in the dropbox. Choose from the range of /1 to /128.
  2. Enter the IP address. An example IPv6 address is ready to use.
  3. Once you are done, you can click the Calculate button.

The IPv6 Subnet Calculator only requires 2 properties:

• Prefix Length: IPv6 prefix-length is the same as the IPv4 subnet mask. It is in four octets written as an integer between 1 through 128.

• IP Address: IPv6 is written in hexadecimal format, with colons (:) between 8 groups of 16 bits, for a total of (8 x 16 = 128) bits. The IPv6 address is represented as x:x:x:x:x:x:x:x, ranges from 0000:0000:0000:0000:0000:0000:0000:0000 to ffff:ffff:ffff:ffff:ffff:ffff:ffff:ffff.


Calculator tool will use that information to calculate and display comprehensive information about:

  • Network Address: The first part of the subnet mask and is the same with the first part of the IP address.
  • Broadcast Address: The last address on the subnet. It is used to send data (broadcast) to every host on that subnet.
  • Total Number of Hosts: Total number of addresses available on the network.
  • Usable Host IP Range: It refers to the range of IP addresses that can be assigned to hosts. The range starts with the address right after the network address and ends at one address before the broadcast address.
  • Number of Usable Hosts: The addresses that can be assigned to hosts. The total number of addresses without the first address (the network address) and the last address (the broadcast address).
  • Wildcard Mask: Wildcard masks refers to the inverted bits of the subnet mask to be used with routing protocols (OSPF) and access control lists (ACLs).
  • Binary Subnet Mask: Subnet mask in binary format.
  • IP Class: IP addresses are categorized into five classes, ranging from Class A to E. Class D is for multicasting and Class E is for future use.
  • CIDR Notation: IP address is written with a number of bits (CIDR number), with a forward-slash (/) in between.
  • IP Type: Show whether the IP address is public (on the Internet) or private (local networks).
  • Binary ID: IP address in binary format, which consists of only 0s and 1s.
  • Integer ID: IP address in integer format, which consists of numbers from 0 – 9.
  • Hex ID: IP address in hexadecimal format, which starts with the “0x”, and consists of numbers from 0 – 9 and letters from A – F.
  • In-addr.arpa: A domain name for reverse DNS lookup. It is the IP addresses in the reverse order. For example, when looking up the IP address of, the returned result is
  • IPv4 Mapped Address: IPv4 Mapped Address is used to present a 32-bit IPv4 address as a 128-bit IPv6 address. Its format starts with 80 “0” bits, followed by 16 bits set in 1s (“FFFF” in hexadecimal), and ends with the original 32-bit IPv4 address written in hexadecimal format.
  • 6to4 Prefix: 6to4 is an IPv4 to IPv6 migration scheme. 6to4 addresses always start with 2002, followed by the original 32-bit IPv4 address written in hexadecimal format. IPv4 Subnet Calculator will also return the data about all the possible networks for that IP address (Network Address, Usable Host Range, Broadcast Address).


  • IP Address: It shows the IP address, followed by the prefix length. The IP address length is shortened, usually by omitting the 0s.
  • Full IP Address: The IPv6 address is written fully in 32-bits without shortening the length.
  • Total IP Addresses: Total number of usable host addresses available on that IPv6 network.
  • Total /64 Networks: Total number of /64 subnets on that network (in IPv6, the default subnet mask is /64).
  • Network: This represents the network address. It is the subnet mask’s first three sets of numbers (the first 48 bits) written in CIDR notation.
  • IP Range: the range of IPv6 addresses that can be assigned to hosts.

A subnet, or a subnetwork, is a subdivision of an IP network. Subnets are formed when a network is divided into two or more linked networks.

Subnetting is the act of creating subnets. Subnetting is used to minimize traffic and improve network speeds. Network speeds will be boosted when separating a big network into numerous smaller networks, thus lowering the number of paths required to locate a single device.

Devices also have a subnet mask, which defines whatever IP address part belongs to the network or the device. To connect to other networks, a gateway is needed. When a device communicates with another device on a different network, the information is routed to the gateway and then to its final destination.

The Internet Protocol (IP) is a data-transfer protocol that allows devices to communicate over the Internet. IPv4 is a 32-bit address, whereas IPv6 is 128-bit. Each device has its IP address, which is drawn from the IPv4 or IPv6 pool, and consists of two parts: the host (the client) and the network (the server).

The network part identifies a specific network and the host part identifies the node (a device). CIDR (Classless Inter-Domain Routing) assigns networks and devices unique IDs. The network address is the same for all hosts in a subnetwork, whereas the host address is unique.

A block of IP addresses is represented by CIDR (Classless Inter-Domain Routing). A CIDR IP address is similar to a regular IP address, except that it ends with a slash and a number, called the IP network prefix.

Subnetwork has three most commonly used classes, which are Class A, B, and C. Each class relates to a specific range of IP addresses and has a default subnet mask.

The below table provides information about the IPv4 subnet:

Class A
Prefix size/
CIDR Notation
Network maskUsable Hosts
Class A
Prefix size/
CIDR Notation
Network maskUsable Hosts
Class B
Prefix size/
CIDR Notation
Network maskUsable Hosts
Class C
Prefix size/
CIDR Notation
Network maskUsable Hosts

IPTP also provides IP addresses together with our network solutions.

Please take a look at our Network services for further information.


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