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IP subnet calculator

Type an address with its prefix or mask to see the network, its usable range and masks. Split it into smaller subnets, or look up any prefix in the reference tables.

Network150.72.0.0/16
Usable hosts65,534
Subnet mask255.255.0.0
Addresses65,536
Network address
150.72.0.0
Broadcast address
150.72.255.255
First usable
150.72.0.1
Last usable
150.72.255.254
Usable hosts
65,534 (65,536 less the network and broadcast addresses)
Subnet mask
255.255.0.0
Wildcard mask
0.0.255.255 (Cisco ACLs, OSPF)
Prefix length
/16
Type
Public public
Old class
B (default /16)
As numbers
Hex 96480000 · Integer 2521300992 to 2521366527
Reverse DNS zone
72.150.in-addr.arpa
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address10010110.01001000..00000000.00000000150.72.0.0
Subnet mask11111111.11111111..00000000.00000000255.255.0.0
Network10010110.01001000..00000000.00000000150.72.0.0
Broadcast10010110.01001000..11111111.11111111150.72.255.255
Split into smaller subnets/23

150.72.0.0/16 makes 128 subnets of /23.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
1150.72.0.0/23150.72.0.1 to 150.72.1.254150.72.1.255510
2150.72.2.0/23150.72.2.1 to 150.72.3.254150.72.3.255510
3150.72.4.0/23150.72.4.1 to 150.72.5.254150.72.5.255510
4150.72.6.0/23150.72.6.1 to 150.72.7.254150.72.7.255510
5150.72.8.0/23150.72.8.1 to 150.72.9.254150.72.9.255510
6150.72.10.0/23150.72.10.1 to 150.72.11.254150.72.11.255510
7150.72.12.0/23150.72.12.1 to 150.72.13.254150.72.13.255510
8150.72.14.0/23150.72.14.1 to 150.72.15.254150.72.15.255510
9150.72.16.0/23150.72.16.1 to 150.72.17.254150.72.17.255510
10150.72.18.0/23150.72.18.1 to 150.72.19.254150.72.19.255510
11150.72.20.0/23150.72.20.1 to 150.72.21.254150.72.21.255510
12150.72.22.0/23150.72.22.1 to 150.72.23.254150.72.23.255510
13150.72.24.0/23150.72.24.1 to 150.72.25.254150.72.25.255510
14150.72.26.0/23150.72.26.1 to 150.72.27.254150.72.27.255510
15150.72.28.0/23150.72.28.1 to 150.72.29.254150.72.29.255510
16150.72.30.0/23150.72.30.1 to 150.72.31.254150.72.31.255510
17150.72.32.0/23150.72.32.1 to 150.72.33.254150.72.33.255510
18150.72.34.0/23150.72.34.1 to 150.72.35.254150.72.35.255510
19150.72.36.0/23150.72.36.1 to 150.72.37.254150.72.37.255510
20150.72.38.0/23150.72.38.1 to 150.72.39.254150.72.39.255510
21150.72.40.0/23150.72.40.1 to 150.72.41.254150.72.41.255510
22150.72.42.0/23150.72.42.1 to 150.72.43.254150.72.43.255510
23150.72.44.0/23150.72.44.1 to 150.72.45.254150.72.45.255510
24150.72.46.0/23150.72.46.1 to 150.72.47.254150.72.47.255510
25150.72.48.0/23150.72.48.1 to 150.72.49.254150.72.49.255510
26150.72.50.0/23150.72.50.1 to 150.72.51.254150.72.51.255510
27150.72.52.0/23150.72.52.1 to 150.72.53.254150.72.53.255510
28150.72.54.0/23150.72.54.1 to 150.72.55.254150.72.55.255510
29150.72.56.0/23150.72.56.1 to 150.72.57.254150.72.57.255510
30150.72.58.0/23150.72.58.1 to 150.72.59.254150.72.59.255510
31150.72.60.0/23150.72.60.1 to 150.72.61.254150.72.61.255510
32150.72.62.0/23150.72.62.1 to 150.72.63.254150.72.63.255510
33150.72.64.0/23150.72.64.1 to 150.72.65.254150.72.65.255510
34150.72.66.0/23150.72.66.1 to 150.72.67.254150.72.67.255510
35150.72.68.0/23150.72.68.1 to 150.72.69.254150.72.69.255510
36150.72.70.0/23150.72.70.1 to 150.72.71.254150.72.71.255510
37150.72.72.0/23150.72.72.1 to 150.72.73.254150.72.73.255510
38150.72.74.0/23150.72.74.1 to 150.72.75.254150.72.75.255510
39150.72.76.0/23150.72.76.1 to 150.72.77.254150.72.77.255510
40150.72.78.0/23150.72.78.1 to 150.72.79.254150.72.79.255510
41150.72.80.0/23150.72.80.1 to 150.72.81.254150.72.81.255510
42150.72.82.0/23150.72.82.1 to 150.72.83.254150.72.83.255510
43150.72.84.0/23150.72.84.1 to 150.72.85.254150.72.85.255510
44150.72.86.0/23150.72.86.1 to 150.72.87.254150.72.87.255510
45150.72.88.0/23150.72.88.1 to 150.72.89.254150.72.89.255510
46150.72.90.0/23150.72.90.1 to 150.72.91.254150.72.91.255510
47150.72.92.0/23150.72.92.1 to 150.72.93.254150.72.93.255510
48150.72.94.0/23150.72.94.1 to 150.72.95.254150.72.95.255510
49150.72.96.0/23150.72.96.1 to 150.72.97.254150.72.97.255510
50150.72.98.0/23150.72.98.1 to 150.72.99.254150.72.99.255510
51150.72.100.0/23150.72.100.1 to 150.72.101.254150.72.101.255510
52150.72.102.0/23150.72.102.1 to 150.72.103.254150.72.103.255510
53150.72.104.0/23150.72.104.1 to 150.72.105.254150.72.105.255510
54150.72.106.0/23150.72.106.1 to 150.72.107.254150.72.107.255510
55150.72.108.0/23150.72.108.1 to 150.72.109.254150.72.109.255510
56150.72.110.0/23150.72.110.1 to 150.72.111.254150.72.111.255510
57150.72.112.0/23150.72.112.1 to 150.72.113.254150.72.113.255510
58150.72.114.0/23150.72.114.1 to 150.72.115.254150.72.115.255510
59150.72.116.0/23150.72.116.1 to 150.72.117.254150.72.117.255510
60150.72.118.0/23150.72.118.1 to 150.72.119.254150.72.119.255510
61150.72.120.0/23150.72.120.1 to 150.72.121.254150.72.121.255510
62150.72.122.0/23150.72.122.1 to 150.72.123.254150.72.123.255510
63150.72.124.0/23150.72.124.1 to 150.72.125.254150.72.125.255510
64150.72.126.0/23150.72.126.1 to 150.72.127.254150.72.127.255510
65150.72.128.0/23150.72.128.1 to 150.72.129.254150.72.129.255510
66150.72.130.0/23150.72.130.1 to 150.72.131.254150.72.131.255510
67150.72.132.0/23150.72.132.1 to 150.72.133.254150.72.133.255510
68150.72.134.0/23150.72.134.1 to 150.72.135.254150.72.135.255510
69150.72.136.0/23150.72.136.1 to 150.72.137.254150.72.137.255510
70150.72.138.0/23150.72.138.1 to 150.72.139.254150.72.139.255510
71150.72.140.0/23150.72.140.1 to 150.72.141.254150.72.141.255510
72150.72.142.0/23150.72.142.1 to 150.72.143.254150.72.143.255510
73150.72.144.0/23150.72.144.1 to 150.72.145.254150.72.145.255510
74150.72.146.0/23150.72.146.1 to 150.72.147.254150.72.147.255510
75150.72.148.0/23150.72.148.1 to 150.72.149.254150.72.149.255510
76150.72.150.0/23150.72.150.1 to 150.72.151.254150.72.151.255510
77150.72.152.0/23150.72.152.1 to 150.72.153.254150.72.153.255510
78150.72.154.0/23150.72.154.1 to 150.72.155.254150.72.155.255510
79150.72.156.0/23150.72.156.1 to 150.72.157.254150.72.157.255510
80150.72.158.0/23150.72.158.1 to 150.72.159.254150.72.159.255510
81150.72.160.0/23150.72.160.1 to 150.72.161.254150.72.161.255510
82150.72.162.0/23150.72.162.1 to 150.72.163.254150.72.163.255510
83150.72.164.0/23150.72.164.1 to 150.72.165.254150.72.165.255510
84150.72.166.0/23150.72.166.1 to 150.72.167.254150.72.167.255510
85150.72.168.0/23150.72.168.1 to 150.72.169.254150.72.169.255510
86150.72.170.0/23150.72.170.1 to 150.72.171.254150.72.171.255510
87150.72.172.0/23150.72.172.1 to 150.72.173.254150.72.173.255510
88150.72.174.0/23150.72.174.1 to 150.72.175.254150.72.175.255510
89150.72.176.0/23150.72.176.1 to 150.72.177.254150.72.177.255510
90150.72.178.0/23150.72.178.1 to 150.72.179.254150.72.179.255510
91150.72.180.0/23150.72.180.1 to 150.72.181.254150.72.181.255510
92150.72.182.0/23150.72.182.1 to 150.72.183.254150.72.183.255510
93150.72.184.0/23150.72.184.1 to 150.72.185.254150.72.185.255510
94150.72.186.0/23150.72.186.1 to 150.72.187.254150.72.187.255510
95150.72.188.0/23150.72.188.1 to 150.72.189.254150.72.189.255510
96150.72.190.0/23150.72.190.1 to 150.72.191.254150.72.191.255510
97150.72.192.0/23150.72.192.1 to 150.72.193.254150.72.193.255510
98150.72.194.0/23150.72.194.1 to 150.72.195.254150.72.195.255510
99150.72.196.0/23150.72.196.1 to 150.72.197.254150.72.197.255510
100150.72.198.0/23150.72.198.1 to 150.72.199.254150.72.199.255510
101150.72.200.0/23150.72.200.1 to 150.72.201.254150.72.201.255510
102150.72.202.0/23150.72.202.1 to 150.72.203.254150.72.203.255510
103150.72.204.0/23150.72.204.1 to 150.72.205.254150.72.205.255510
104150.72.206.0/23150.72.206.1 to 150.72.207.254150.72.207.255510
105150.72.208.0/23150.72.208.1 to 150.72.209.254150.72.209.255510
106150.72.210.0/23150.72.210.1 to 150.72.211.254150.72.211.255510
107150.72.212.0/23150.72.212.1 to 150.72.213.254150.72.213.255510
108150.72.214.0/23150.72.214.1 to 150.72.215.254150.72.215.255510
109150.72.216.0/23150.72.216.1 to 150.72.217.254150.72.217.255510
110150.72.218.0/23150.72.218.1 to 150.72.219.254150.72.219.255510
111150.72.220.0/23150.72.220.1 to 150.72.221.254150.72.221.255510
112150.72.222.0/23150.72.222.1 to 150.72.223.254150.72.223.255510
113150.72.224.0/23150.72.224.1 to 150.72.225.254150.72.225.255510
114150.72.226.0/23150.72.226.1 to 150.72.227.254150.72.227.255510
115150.72.228.0/23150.72.228.1 to 150.72.229.254150.72.229.255510
116150.72.230.0/23150.72.230.1 to 150.72.231.254150.72.231.255510
117150.72.232.0/23150.72.232.1 to 150.72.233.254150.72.233.255510
118150.72.234.0/23150.72.234.1 to 150.72.235.254150.72.235.255510
119150.72.236.0/23150.72.236.1 to 150.72.237.254150.72.237.255510
120150.72.238.0/23150.72.238.1 to 150.72.239.254150.72.239.255510
121150.72.240.0/23150.72.240.1 to 150.72.241.254150.72.241.255510
122150.72.242.0/23150.72.242.1 to 150.72.243.254150.72.243.255510
123150.72.244.0/23150.72.244.1 to 150.72.245.254150.72.245.255510
124150.72.246.0/23150.72.246.1 to 150.72.247.254150.72.247.255510
125150.72.248.0/23150.72.248.1 to 150.72.249.254150.72.249.255510
126150.72.250.0/23150.72.250.1 to 150.72.251.254150.72.251.255510
127150.72.252.0/23150.72.252.1 to 150.72.253.254150.72.253.255510
128150.72.254.0/23150.72.254.1 to 150.72.255.254150.72.255.255510

IPv4 CIDR reference (/0 to /32)

IPv4 prefix lengths
PrefixSubnet maskWildcardAddressesUsable hostsSizeTypical use
/00.0.0.0255.255.255.2554,294,967,2964,294,967,29416,777,216 × /24
/1128.0.0.0127.255.255.2552,147,483,6482,147,483,6468,388,608 × /24
/2192.0.0.063.255.255.2551,073,741,8241,073,741,8224,194,304 × /24
/3224.0.0.031.255.255.255536,870,912536,870,9102,097,152 × /24
/4240.0.0.015.255.255.255268,435,456268,435,4541,048,576 × /24
/5248.0.0.07.255.255.255134,217,728134,217,726524,288 × /24
/6252.0.0.03.255.255.25567,108,86467,108,862262,144 × /24
/7254.0.0.01.255.255.25533,554,43233,554,430131,072 × /24
/8255.0.0.00.255.255.25516,777,21616,777,21465,536 × /24Old class A; 10.0.0.0/8
/9255.128.0.00.127.255.2558,388,6088,388,60632,768 × /24
/10255.192.0.00.63.255.2554,194,3044,194,30216,384 × /24
/11255.224.0.00.31.255.2552,097,1522,097,1508,192 × /24
/12255.240.0.00.15.255.2551,048,5761,048,5744,096 × /24172.16.0.0/12
/13255.248.0.00.7.255.255524,288524,2862,048 × /24
/14255.252.0.00.3.255.255262,144262,1421,024 × /24
/15255.254.0.00.1.255.255131,072131,070512 × /24
/16255.255.0.00.0.255.25565,53665,534256 × /24Old class B; 192.168.0.0/16
/17255.255.128.00.0.127.25532,76832,766128 × /24
/18255.255.192.00.0.63.25516,38416,38264 × /24
/19255.255.224.00.0.31.2558,1928,19032 × /24
/20255.255.240.00.0.15.2554,0964,09416 × /24
/21255.255.248.00.0.7.2552,0482,0468 × /24
/22255.255.252.00.0.3.2551,0241,0224 × /24Large office or guest Wi-Fi (1,022 hosts)
/23255.255.254.00.0.1.2555125102 × /24Larger office LAN (510 hosts)
/24255.255.255.00.0.0.2552562541 × /24Typical office LAN (old class C)
/25255.255.255.1280.0.0.1271281261/2 of a /24Smaller LAN or VLAN
/26255.255.255.1920.0.0.6364621/4 of a /24Smaller LAN or VLAN
/27255.255.255.2240.0.0.3132301/8 of a /24Small VLAN, phones, cameras
/28255.255.255.2400.0.0.1516141/16 of a /24Small VLAN, phones, cameras
/29255.255.255.2480.0.0.7861/32 of a /24Small fixed public block (5 usable)
/30255.255.255.2520.0.0.3421/64 of a /24Point-to-point (old style)
/31255.255.255.2540.0.0.1221/128 of a /24Point-to-point link (RFC 3021)
/32255.255.255.2550.0.0.0111/256 of a /24One host

IPv6 prefix reference

IPv6 prefix lengths
PrefixAddresses/64 LANs/48 sitesNibbleTypical use
/342,535,295,865,117,307,932,921,825,928,971,026,432 (2^125)2,305,843,009,213,693,95235,184,372,088,832NoAll global unicast (2000::/3)
/165,192,296,858,534,827,628,530,496,329,220,096 (2^112)281,474,976,710,6564,294,967,296Yes
/20324,518,553,658,426,726,783,156,020,576,256 (2^108)17,592,186,044,416268,435,456YesLarge provider allocation (RIPE minimum for some)
/29633,825,300,114,114,700,748,351,602,688 (2^99)34,359,738,368524,288NoRIPE allocation to a provider (often)
/3279,228,162,514,264,337,593,543,950,336 (2^96)4,294,967,29665,536YesProvider allocation (RIPE default)
/364,951,760,157,141,521,099,596,496,896 (2^92)268,435,4564,096Yes
/40309,485,009,821,345,068,724,781,056 (2^88)16,777,216256Yes
/4419,342,813,113,834,066,795,298,816 (2^84)1,048,57616Yes
/481,208,925,819,614,629,174,706,176 (2^80)65,5361YesOne site or organisation (RIPE PI / assignment)
/5275,557,863,725,914,323,419,136 (2^76)4,096Yes
/564,722,366,482,869,645,213,696 (2^72)256YesSmall site or home (common provider assignment)
/60295,147,905,179,352,825,856 (2^68)16YesSome home broadband (16 LANs)
/6418,446,744,073,709,551,616 (2^64)1YesOne LAN or VLAN (needed for SLAAC)
/7272,057,594,037,927,936 (2^56)1/256 of a /64Yes
/80281,474,976,710,656 (2^48)1/65,536 of a /64Yes
/964,294,967,2961/4,294,967,296 of a /64YesEmbeds an IPv4 address (NAT64)
/11265,5361/281,474,976,710,656 of a /64Yes
/1202561/72,057,594,037,927,936 of a /64Yes
/124161/1,152,921,504,606,846,976 of a /64Yes
/12641/4,611,686,018,427,387,904 of a /64No
/12721/9,223,372,036,854,775,808 of a /64NoPoint-to-point link (RFC 6164)
/12811/18,446,744,073,709,551,616 of a /64YesOne host or loopback

Private and special ranges

IPv4

Special-purpose ranges
RangeNameWhat it is
255.255.255.255/32Limited broadcastEvery host on the local network
0.0.0.0/8This networkNot routed; 0.0.0.0 means "any address" in settings
10.0.0.0/8Private (RFC 1918)Office and home networks; not routed on the internet
100.64.0.0/10Shared address space (CGNAT)Used by providers behind carrier-grade NAT (RFC 6598)
127.0.0.0/8LoopbackThis computer
169.254.0.0/16Link-local (APIPA)Self-assigned when no DHCP server answers
172.16.0.0/12Private (RFC 1918)Office and home networks; not routed on the internet
192.0.0.0/24IETF protocol assignmentsSpecial uses such as DS-Lite
192.0.2.0/24Documentation (TEST-NET-1)For examples; never used on a network
192.88.99.0/246to4 relay (deprecated)Formerly anycast for 6to4
192.168.0.0/16Private (RFC 1918)Office and home networks; not routed on the internet
198.18.0.0/15BenchmarkingNetwork equipment testing (RFC 2544)
198.51.100.0/24Documentation (TEST-NET-2)For examples; never used on a network
203.0.113.0/24Documentation (TEST-NET-3)For examples; never used on a network
224.0.0.0/4MulticastOne-to-many traffic, such as IPTV and routing protocols
240.0.0.0/4ReservedFuture use; not usable on most systems

IPv6

Special-purpose ranges
RangeNameWhat it is
::/128UnspecifiedNo address; :: means "any address" in settings
::1/128LoopbackThis computer
::ffff:0:0/96IPv4-mappedAn IPv4 address written as IPv6
64:ff9b::/96NAT64IPv4 addresses reached through a NAT64 gateway
100::/64Discard onlyTraffic sent here is dropped (RFC 6666)
2001:db8::/32DocumentationFor examples; never used on a network
2001::/32TeredoIPv6 tunnelled over IPv4 UDP
2002::/166to4IPv6 tunnelled over IPv4 (largely retired)
3fff::/20DocumentationFor examples (RFC 9637)
fc00::/7Unique local (ULA)Private IPv6, like RFC 1918; usually fd00::/8
fe80::/10Link-localEvery IPv6 interface has one; not routed
ff00::/8MulticastOne-to-many traffic; replaces broadcast
2000::/3Global unicastPublic internet addresses