Network and IP address calculator
The netmask in "bits format" is also known as mask in CIDR format (CIDR=Classless Inter-Domain Routing).
Converters for Network and IP address
Subnet Mask Converter (dotted decimal to bits format)
Subnet Mask Converter (bits format to dotted decimal)
Number of required addresses to netmask converter
Convert dotted decimal IP-address or mask to binary and hex
Convert hex IP-address or mask dotted decimal
Calculate the bit-complement of an IP-address (invert)
Convert a Network Mask to amount of usable addresses
Convert decimal to binary and hex |
Convert binary to decimal and hex |
Convert hex to decimal and binary |
IP Multicast address ranges
All multicast addresses can easily be recognized because they start with the bit pattern "1110".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
Mask Hosts Usable Netmask Hex Mask /30 4 2 255.255.255.252 fffffffc this is 1/64 of a Class C net /29 8 6 255.255.255.248 fffffff8 this is 1/32 of a Class C net /28 16 14 255.255.255.240 fffffff0 this is 1/16 of a Class C net /27 32 30 255.255.255.224 ffffffe0 this is 1/8 of a Class C net /26 64 62 255.255.255.192 ffffffc0 this is 1/4 of a Class C net /24 256 254 255.255.255.0 ffffff00 this is a Class C net /23 512 510 255.255.254.0 fffffe00 these are 2 Class C net /22 1024 1022 255.255.252.0 fffffc00 these are 4 Class C net /21 2048 2046 255.255.248.0 fffff800 these are 8 Class C net /20 4096 4094 255.255.240.0 fffff000 these are 16 Class C net /19 8192 8190 255.255.224.0 ffffe000 these are 32 Class C net /18 16384 16382 255.255.192.0 ffffc000 these are 64 Class C net /17 32768 32766 255.255.128.0 ffff8000 these are 128 Class C net /16 65536 65534 255.255.0.0 ffff0000 these are 256 Class C net = Class B net
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© Guido Socher, Version: 2008-09-14
© Guido Socher, Version: 2008-09-14