IP networks and subnets calculator
Online utility for IP address calculations including netmask, broadcast and network addresses, wildcard mask, usable ranges, address format conversion etc. Accepts IP-s in hex/dec and also as one unsigned int number.

Inputs data - host#

IP decimal
(many formats)
3 238 121 7
IP hex
(many formats)
03 ee 79 07
IP integer
(unsigned int)
IP classA (1 - 126)

Inputs data - network#

network class
first octet legal values0 - 255
network bits0
mask bits
(net + subnet)
subnet bits
network mask
host mask
maximum subnets
hosts per subnet

Results - details about subnets#

subnet address0.0.0.0
subnet broadcast address255.255.255.255
host range0.0.0.1 -
subnet bitmaphhhhhhhh.hhhhhhhh.hhhhhhhh.hhhhhhhh

Some facts#

  • Your IP address is: [unknown ip].
  • The IP address identifies the network interface, the group of interfaces (broadcast, multicast), or the entire network (subnet).
  • The IP addresses work on the third level of the OSI (network level).
  • The IP address does not identify physical device (computer) in the unique way. Multiple computers can share the same IP address and assigned address can change (dynamic IP).
  • IPv4 address (IP version 4) is the basis of the internet. Despite the appearance of IPv6, most of the services still use the IPv4 version.
  • The IPv4 address is a 32-bit integer number. Most often it is represented as 4 bytes separated by a dot. For example IP address of calculla website is*.

    *) This address may have changed since the time when this text was written.

What is the meaning of each calculator field ?#

  • Inputs data (host) - Enter IP address in any format for further calculations here. Just fill any of the "host" fields and other fields in this section will be filled automatically with a converted value.
    • IP decimal (many formats) - IP address as four decimal numbers (from 0 to 255) separated by dots e.g.
    • IP hex (many formats) - IP address as hexadecimal number. You can enter four dot-separated numbers (e.g. aa.bb.cc.dd) or one 32-bit hex (e.g. aabbccdd) here.
    • IP integer (unsigned int) - IP address as 32-bit unsigned integer number eg. 2864434397.
    • IP class - calculated class of your IP address goes here (A,B,C,D). This field has historical meaning only, because IP classes are not in use anymore.

  • Inputs data (network) - data in these section determine how your IP adress will be splitted into network (subnet) and host parts.
    • network class - use this field if you're going to apply division based on network classes (A,B,C).
    • first octet legal values - this field shows range of values, which can occur at the begin of IP address. This field depends on selected network class.
    • network bits - number of bits reserved for network part according to selected network class.
    • bity maski (net + subnet) - total number of bits used to address network including subnet. If we remove these bits, we'll got host bits only.
    • subnet bits - number of bits reserved for subnet.
    • network mask - bit mask allowing us to get network part from final IP address (bitwise AND operation).
    • host mask (wildcard) - bit mask allowing us to get host part from final IP address (bitwise AND operation).
    • maximum subnets - the maximum number of subnetworks possible to address. This value depends on number of subnet bits.
    • hosts per subnet - the maximum number of hosts within sigle subnet. This value depends on number of host bits.

  • Results - details about subnets
    • subnet address - this is one of two special (reserved) addresses within created subnetwork. This address is related to the subnetwork itself and it's used by network devices internally.
    • subnet broadcast address - second special (reserved) address. If we send packet to this address, it will be delivered to all hosts within subnetwork.
    • hosts range - range of final IP addresses assigned to hosts within created subnet.
    • subnet bitmap - diagram-like display of what are the roles of selected bits within final IP address. The meaning of used symbols is:
      • n - network bits,
      • s - subnet bits,
      • h - host bits.
      Also, one (class A), two (class B) or three (class C) bits are reserved to encode network class if used.

History of changes, improvements and fixes to this calculator#

2015.02.07 New implementation: This calculator has been rewritten. The previous implementation was server-side (made in PHP). Each time the new value was entered or any button clicked, the full website reload was triggered. Current implementation works fully client-side - it's written in JavaScipt. No more reloads !

Tags and links to this website#

What tags this calculator has#


This is permalink. Permalink is the link containing your input data. Just copy it and share your work with friends:

Links to external sites (leaving Calculla?)#

Ancient version of this site - links#

In December 2016 the Calculla website has been republished using new technologies and all calculators have been rewritten. Old version of the Calculla is still available through this link: v1.calculla.com. We left the version 1 of Calculla untouched for archival purposes.
Direct link to the old version:
"Calculla v1" version of this calculator
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