network address calculator / ip address calculator

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Show network, broadcast, first and last address for a given network:

IP/Netmask bits: /

result:

Usable addresses:
Mask:
Network:
First usable:
Last usable:
Broadcast:

The netmask in “bits format” is also known as mask in CIDR format (CIDR=Classless Inter-Domain Routing).

Converters for Network and IP addresses

Subnet Mask Converter -- dotted decimal to bits format (CIDR)

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Subnet Mask Converter -- bits format to dotted decimal

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Number of required addresses to netmask converter

number of addresses needed:

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mask: / dotted dec. mask:
usable amount of addresses:

Convert dotted decimal IP-address or mask to binary and hex



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Convert hex IP-address or mask dotted decimal



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dotted decimal:
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Calculate the bit-complement of an IP-address (invert)

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Convert a Network Mask to amount of usable addresses

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Usable amount of addr: Total number of addr:
Netmaks in dotted decimal format:

Convert decimal to binary and hex

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Convert binary to decimal and hex

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Convert hex to decimal and binary

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IP Multicast address ranges

All multicast addresses can easily be recognized because they start with the bit pattern "1110". This originates from the classful network design of the early Internet when this group of addresses was designated as a Class D.

224.0.0.0 - 224.0.0.255 Well-known multicast addresses, control channels
224.0.1.0 - 238.255.255.255 Globally-scoped (Internet-wide) multicast addresses
239.0.0.0 - 239.255.255.255 Local multicast addresses

Special and private address ranges

Private address ranges are not routed on the Internet and can be freely allocated in any private network. NAT (network address translation) is required when connecting such a network to the Internet.

Private network addresses (RFC1597/RFC1918 addresses):
10.0.0.0 - 10.255.255.255 A 24-bit block, /8, class A network
172.16.0.0 - 172.31.255.255 A 20-bit block, /12, set of 16 contiguous class B network numbers
192.168.0.0 - 192.168.255.255 A 16-bit block, /16, set of 255 contiguous class C network numbers

Special addresses:
127.0.0.0 - 127.255.255.255 Special address range for the localhost. You can normally not use those addresses for anything else. 127.0.0.1 is generally assigned to the loopback device
0.0.0.0 Special host address commonly reserved for the default route

Overview of common subnets and masks

/CIDR MaskHostsUsable NetmaskHex Maskcomments
/32 11255.255.255.255ffffffffthis is 1/128 of a Class C net
/30 42255.255.255.252fffffffcthis is 1/64 of a Class C net
/29 86255.255.255.248fffffff8this is 1/32 of a Class C net
/28 1614255.255.255.240fffffff0this is 1/16 of a Class C net
/27 3230255.255.255.224ffffffe0this is 1/8 of a Class C net
/26 6462255.255.255.192ffffffc0this is 1/4 of a Class C net
/25 128126255.255.255.128ffffff80
/24 256254255.255.255.0ffffff00this is a Class C net
/23 512510255.255.254.0fffffe00these are 2 Class C net
/22 10241022255.255.252.0fffffc00these are 4 Class C net
/21 20482046255.255.248.0fffff800these are 8 Class C net
/20 40964094255.255.240.0fffff000these are 16 Class C net
/19 81928190255.255.224.0ffffe000these are 32 Class C net
/18 1638416382255.255.192.0ffffc000these are 64 Class C net
/17 3276832766255.255.128.0ffff8000these are 128 Class C net
/16 6553665534255.255.0.0ffff0000these are 256 Class C net = Class B net

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