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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.

Network114.167.0.0/16
Usable hosts65,534
Subnet mask255.255.0.0
Addresses65,536
Network address
114.167.0.0
Broadcast address
114.167.255.255
First usable
114.167.0.1
Last usable
114.167.255.254
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
A (default /8)
As numbers
Hex 72A70000 · Integer 1923547136 to 1923612671
Reverse DNS zone
167.114.in-addr.arpa
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address01110010.10100111..00000000.00000000114.167.0.0
Subnet mask11111111.11111111..00000000.00000000255.255.0.0
Network01110010.10100111..00000000.00000000114.167.0.0
Broadcast01110010.10100111..11111111.11111111114.167.255.255
Split into smaller subnets/23
/17 (2)/18 (4)/19 (8)/20 (16)/21 (32)/22 (64)/23 (128)/24 (256)/25 (512)/26 (1,024)/27 (2,048)/28 (4,096)

114.167.0.0/16 makes 128 subnets of /23.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
1114.167.0.0/23114.167.0.1 to 114.167.1.254114.167.1.255510
2114.167.2.0/23114.167.2.1 to 114.167.3.254114.167.3.255510
3114.167.4.0/23114.167.4.1 to 114.167.5.254114.167.5.255510
4114.167.6.0/23114.167.6.1 to 114.167.7.254114.167.7.255510
5114.167.8.0/23114.167.8.1 to 114.167.9.254114.167.9.255510
6114.167.10.0/23114.167.10.1 to 114.167.11.254114.167.11.255510
7114.167.12.0/23114.167.12.1 to 114.167.13.254114.167.13.255510
8114.167.14.0/23114.167.14.1 to 114.167.15.254114.167.15.255510
9114.167.16.0/23114.167.16.1 to 114.167.17.254114.167.17.255510
10114.167.18.0/23114.167.18.1 to 114.167.19.254114.167.19.255510
11114.167.20.0/23114.167.20.1 to 114.167.21.254114.167.21.255510
12114.167.22.0/23114.167.22.1 to 114.167.23.254114.167.23.255510
13114.167.24.0/23114.167.24.1 to 114.167.25.254114.167.25.255510
14114.167.26.0/23114.167.26.1 to 114.167.27.254114.167.27.255510
15114.167.28.0/23114.167.28.1 to 114.167.29.254114.167.29.255510
16114.167.30.0/23114.167.30.1 to 114.167.31.254114.167.31.255510
17114.167.32.0/23114.167.32.1 to 114.167.33.254114.167.33.255510
18114.167.34.0/23114.167.34.1 to 114.167.35.254114.167.35.255510
19114.167.36.0/23114.167.36.1 to 114.167.37.254114.167.37.255510
20114.167.38.0/23114.167.38.1 to 114.167.39.254114.167.39.255510
21114.167.40.0/23114.167.40.1 to 114.167.41.254114.167.41.255510
22114.167.42.0/23114.167.42.1 to 114.167.43.254114.167.43.255510
23114.167.44.0/23114.167.44.1 to 114.167.45.254114.167.45.255510
24114.167.46.0/23114.167.46.1 to 114.167.47.254114.167.47.255510
25114.167.48.0/23114.167.48.1 to 114.167.49.254114.167.49.255510
26114.167.50.0/23114.167.50.1 to 114.167.51.254114.167.51.255510
27114.167.52.0/23114.167.52.1 to 114.167.53.254114.167.53.255510
28114.167.54.0/23114.167.54.1 to 114.167.55.254114.167.55.255510
29114.167.56.0/23114.167.56.1 to 114.167.57.254114.167.57.255510
30114.167.58.0/23114.167.58.1 to 114.167.59.254114.167.59.255510
31114.167.60.0/23114.167.60.1 to 114.167.61.254114.167.61.255510
32114.167.62.0/23114.167.62.1 to 114.167.63.254114.167.63.255510
33114.167.64.0/23114.167.64.1 to 114.167.65.254114.167.65.255510
34114.167.66.0/23114.167.66.1 to 114.167.67.254114.167.67.255510
35114.167.68.0/23114.167.68.1 to 114.167.69.254114.167.69.255510
36114.167.70.0/23114.167.70.1 to 114.167.71.254114.167.71.255510
37114.167.72.0/23114.167.72.1 to 114.167.73.254114.167.73.255510
38114.167.74.0/23114.167.74.1 to 114.167.75.254114.167.75.255510
39114.167.76.0/23114.167.76.1 to 114.167.77.254114.167.77.255510
40114.167.78.0/23114.167.78.1 to 114.167.79.254114.167.79.255510
41114.167.80.0/23114.167.80.1 to 114.167.81.254114.167.81.255510
42114.167.82.0/23114.167.82.1 to 114.167.83.254114.167.83.255510
43114.167.84.0/23114.167.84.1 to 114.167.85.254114.167.85.255510
44114.167.86.0/23114.167.86.1 to 114.167.87.254114.167.87.255510
45114.167.88.0/23114.167.88.1 to 114.167.89.254114.167.89.255510
46114.167.90.0/23114.167.90.1 to 114.167.91.254114.167.91.255510
47114.167.92.0/23114.167.92.1 to 114.167.93.254114.167.93.255510
48114.167.94.0/23114.167.94.1 to 114.167.95.254114.167.95.255510
49114.167.96.0/23114.167.96.1 to 114.167.97.254114.167.97.255510
50114.167.98.0/23114.167.98.1 to 114.167.99.254114.167.99.255510
51114.167.100.0/23114.167.100.1 to 114.167.101.254114.167.101.255510
52114.167.102.0/23114.167.102.1 to 114.167.103.254114.167.103.255510
53114.167.104.0/23114.167.104.1 to 114.167.105.254114.167.105.255510
54114.167.106.0/23114.167.106.1 to 114.167.107.254114.167.107.255510
55114.167.108.0/23114.167.108.1 to 114.167.109.254114.167.109.255510
56114.167.110.0/23114.167.110.1 to 114.167.111.254114.167.111.255510
57114.167.112.0/23114.167.112.1 to 114.167.113.254114.167.113.255510
58114.167.114.0/23114.167.114.1 to 114.167.115.254114.167.115.255510
59114.167.116.0/23114.167.116.1 to 114.167.117.254114.167.117.255510
60114.167.118.0/23114.167.118.1 to 114.167.119.254114.167.119.255510
61114.167.120.0/23114.167.120.1 to 114.167.121.254114.167.121.255510
62114.167.122.0/23114.167.122.1 to 114.167.123.254114.167.123.255510
63114.167.124.0/23114.167.124.1 to 114.167.125.254114.167.125.255510
64114.167.126.0/23114.167.126.1 to 114.167.127.254114.167.127.255510
65114.167.128.0/23114.167.128.1 to 114.167.129.254114.167.129.255510
66114.167.130.0/23114.167.130.1 to 114.167.131.254114.167.131.255510
67114.167.132.0/23114.167.132.1 to 114.167.133.254114.167.133.255510
68114.167.134.0/23114.167.134.1 to 114.167.135.254114.167.135.255510
69114.167.136.0/23114.167.136.1 to 114.167.137.254114.167.137.255510
70114.167.138.0/23114.167.138.1 to 114.167.139.254114.167.139.255510
71114.167.140.0/23114.167.140.1 to 114.167.141.254114.167.141.255510
72114.167.142.0/23114.167.142.1 to 114.167.143.254114.167.143.255510
73114.167.144.0/23114.167.144.1 to 114.167.145.254114.167.145.255510
74114.167.146.0/23114.167.146.1 to 114.167.147.254114.167.147.255510
75114.167.148.0/23114.167.148.1 to 114.167.149.254114.167.149.255510
76114.167.150.0/23114.167.150.1 to 114.167.151.254114.167.151.255510
77114.167.152.0/23114.167.152.1 to 114.167.153.254114.167.153.255510
78114.167.154.0/23114.167.154.1 to 114.167.155.254114.167.155.255510
79114.167.156.0/23114.167.156.1 to 114.167.157.254114.167.157.255510
80114.167.158.0/23114.167.158.1 to 114.167.159.254114.167.159.255510
81114.167.160.0/23114.167.160.1 to 114.167.161.254114.167.161.255510
82114.167.162.0/23114.167.162.1 to 114.167.163.254114.167.163.255510
83114.167.164.0/23114.167.164.1 to 114.167.165.254114.167.165.255510
84114.167.166.0/23114.167.166.1 to 114.167.167.254114.167.167.255510
85114.167.168.0/23114.167.168.1 to 114.167.169.254114.167.169.255510
86114.167.170.0/23114.167.170.1 to 114.167.171.254114.167.171.255510
87114.167.172.0/23114.167.172.1 to 114.167.173.254114.167.173.255510
88114.167.174.0/23114.167.174.1 to 114.167.175.254114.167.175.255510
89114.167.176.0/23114.167.176.1 to 114.167.177.254114.167.177.255510
90114.167.178.0/23114.167.178.1 to 114.167.179.254114.167.179.255510
91114.167.180.0/23114.167.180.1 to 114.167.181.254114.167.181.255510
92114.167.182.0/23114.167.182.1 to 114.167.183.254114.167.183.255510
93114.167.184.0/23114.167.184.1 to 114.167.185.254114.167.185.255510
94114.167.186.0/23114.167.186.1 to 114.167.187.254114.167.187.255510
95114.167.188.0/23114.167.188.1 to 114.167.189.254114.167.189.255510
96114.167.190.0/23114.167.190.1 to 114.167.191.254114.167.191.255510
97114.167.192.0/23114.167.192.1 to 114.167.193.254114.167.193.255510
98114.167.194.0/23114.167.194.1 to 114.167.195.254114.167.195.255510
99114.167.196.0/23114.167.196.1 to 114.167.197.254114.167.197.255510
100114.167.198.0/23114.167.198.1 to 114.167.199.254114.167.199.255510
101114.167.200.0/23114.167.200.1 to 114.167.201.254114.167.201.255510
102114.167.202.0/23114.167.202.1 to 114.167.203.254114.167.203.255510
103114.167.204.0/23114.167.204.1 to 114.167.205.254114.167.205.255510
104114.167.206.0/23114.167.206.1 to 114.167.207.254114.167.207.255510
105114.167.208.0/23114.167.208.1 to 114.167.209.254114.167.209.255510
106114.167.210.0/23114.167.210.1 to 114.167.211.254114.167.211.255510
107114.167.212.0/23114.167.212.1 to 114.167.213.254114.167.213.255510
108114.167.214.0/23114.167.214.1 to 114.167.215.254114.167.215.255510
109114.167.216.0/23114.167.216.1 to 114.167.217.254114.167.217.255510
110114.167.218.0/23114.167.218.1 to 114.167.219.254114.167.219.255510
111114.167.220.0/23114.167.220.1 to 114.167.221.254114.167.221.255510
112114.167.222.0/23114.167.222.1 to 114.167.223.254114.167.223.255510
113114.167.224.0/23114.167.224.1 to 114.167.225.254114.167.225.255510
114114.167.226.0/23114.167.226.1 to 114.167.227.254114.167.227.255510
115114.167.228.0/23114.167.228.1 to 114.167.229.254114.167.229.255510
116114.167.230.0/23114.167.230.1 to 114.167.231.254114.167.231.255510
117114.167.232.0/23114.167.232.1 to 114.167.233.254114.167.233.255510
118114.167.234.0/23114.167.234.1 to 114.167.235.254114.167.235.255510
119114.167.236.0/23114.167.236.1 to 114.167.237.254114.167.237.255510
120114.167.238.0/23114.167.238.1 to 114.167.239.254114.167.239.255510
121114.167.240.0/23114.167.240.1 to 114.167.241.254114.167.241.255510
122114.167.242.0/23114.167.242.1 to 114.167.243.254114.167.243.255510
123114.167.244.0/23114.167.244.1 to 114.167.245.254114.167.245.255510
124114.167.246.0/23114.167.246.1 to 114.167.247.254114.167.247.255510
125114.167.248.0/23114.167.248.1 to 114.167.249.254114.167.249.255510
126114.167.250.0/23114.167.250.1 to 114.167.251.254114.167.251.255510
127114.167.252.0/23114.167.252.1 to 114.167.253.254114.167.253.255510
128114.167.254.0/23114.167.254.1 to 114.167.255.254114.167.255.255510

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

About this tool

A network is written as an address and a prefix length, such as 192.168.1.0/24: the first 24 bits name the network and the rest number the devices on it. The calculator works out where the network starts and ends, how many devices it holds, its subnet and wildcard masks, and the reverse DNS zone to ask your provider for.

It also splits a network into equal smaller ones (one per VLAN or site), turns a range of addresses into the fewest CIDR blocks for a firewall rule, and lists every IPv4 prefix length and the common IPv6 ones in reference tables.

Common questions

Why are two addresses lost in every IPv4 subnet?

The first address names the network and the last is the broadcast address, so a /24 has 256 addresses but 254 for devices. A /31 (a link between two routers) and a /32 (one host) are the exceptions.

What size of IPv6 network should a LAN use?

Always /64. Devices pick their own address within it (SLAAC), which needs the full 64 bits. A site usually gets a /48 or /56 from its provider, which holds 65,536 or 256 LANs.

What is a wildcard mask?

The subnet mask turned inside out: 255.255.255.0 becomes 0.0.0.255. Cisco access lists and OSPF use it to say which bits must match.

Which ranges can I use inside an office?

IPv4: 10.0.0.0/8, 172.16.0.0/12 and 192.168.0.0/16. IPv6: unique local addresses from fd00::/8, though most networks use the public prefix from their provider.