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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.

Network214.0.0.0/8
Usable hosts16,777,214
Subnet mask255.0.0.0
Addresses16,777,216
Network address
214.0.0.0
Broadcast address
214.255.255.255
First usable
214.0.0.1
Last usable
214.255.255.254
Usable hosts
16,777,214 (16,777,216 less the network and broadcast addresses)
Subnet mask
255.0.0.0
Wildcard mask
0.255.255.255 (Cisco ACLs, OSPF)
Prefix length
/8
Type
Public public
Old class
C (default /24)
As numbers
Hex D6000000 · Integer 3590324224 to 3607101439
Reverse DNS zone
214.in-addr.arpa
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address11010110..00000000.00000000.00000000214.0.0.0
Subnet mask11111111..00000000.00000000.00000000255.0.0.0
Network11010110..00000000.00000000.00000000214.0.0.0
Broadcast11010110..11111111.11111111.11111111214.255.255.255
Split into smaller subnets/15
/9 (2)/10 (4)/11 (8)/12 (16)/13 (32)/14 (64)/15 (128)/16 (256)/17 (512)/18 (1,024)/19 (2,048)/20 (4,096)

214.0.0.0/8 makes 128 subnets of /15.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
1214.0.0.0/15214.0.0.1 to 214.1.255.254214.1.255.255131,070
2214.2.0.0/15214.2.0.1 to 214.3.255.254214.3.255.255131,070
3214.4.0.0/15214.4.0.1 to 214.5.255.254214.5.255.255131,070
4214.6.0.0/15214.6.0.1 to 214.7.255.254214.7.255.255131,070
5214.8.0.0/15214.8.0.1 to 214.9.255.254214.9.255.255131,070
6214.10.0.0/15214.10.0.1 to 214.11.255.254214.11.255.255131,070
7214.12.0.0/15214.12.0.1 to 214.13.255.254214.13.255.255131,070
8214.14.0.0/15214.14.0.1 to 214.15.255.254214.15.255.255131,070
9214.16.0.0/15214.16.0.1 to 214.17.255.254214.17.255.255131,070
10214.18.0.0/15214.18.0.1 to 214.19.255.254214.19.255.255131,070
11214.20.0.0/15214.20.0.1 to 214.21.255.254214.21.255.255131,070
12214.22.0.0/15214.22.0.1 to 214.23.255.254214.23.255.255131,070
13214.24.0.0/15214.24.0.1 to 214.25.255.254214.25.255.255131,070
14214.26.0.0/15214.26.0.1 to 214.27.255.254214.27.255.255131,070
15214.28.0.0/15214.28.0.1 to 214.29.255.254214.29.255.255131,070
16214.30.0.0/15214.30.0.1 to 214.31.255.254214.31.255.255131,070
17214.32.0.0/15214.32.0.1 to 214.33.255.254214.33.255.255131,070
18214.34.0.0/15214.34.0.1 to 214.35.255.254214.35.255.255131,070
19214.36.0.0/15214.36.0.1 to 214.37.255.254214.37.255.255131,070
20214.38.0.0/15214.38.0.1 to 214.39.255.254214.39.255.255131,070
21214.40.0.0/15214.40.0.1 to 214.41.255.254214.41.255.255131,070
22214.42.0.0/15214.42.0.1 to 214.43.255.254214.43.255.255131,070
23214.44.0.0/15214.44.0.1 to 214.45.255.254214.45.255.255131,070
24214.46.0.0/15214.46.0.1 to 214.47.255.254214.47.255.255131,070
25214.48.0.0/15214.48.0.1 to 214.49.255.254214.49.255.255131,070
26214.50.0.0/15214.50.0.1 to 214.51.255.254214.51.255.255131,070
27214.52.0.0/15214.52.0.1 to 214.53.255.254214.53.255.255131,070
28214.54.0.0/15214.54.0.1 to 214.55.255.254214.55.255.255131,070
29214.56.0.0/15214.56.0.1 to 214.57.255.254214.57.255.255131,070
30214.58.0.0/15214.58.0.1 to 214.59.255.254214.59.255.255131,070
31214.60.0.0/15214.60.0.1 to 214.61.255.254214.61.255.255131,070
32214.62.0.0/15214.62.0.1 to 214.63.255.254214.63.255.255131,070
33214.64.0.0/15214.64.0.1 to 214.65.255.254214.65.255.255131,070
34214.66.0.0/15214.66.0.1 to 214.67.255.254214.67.255.255131,070
35214.68.0.0/15214.68.0.1 to 214.69.255.254214.69.255.255131,070
36214.70.0.0/15214.70.0.1 to 214.71.255.254214.71.255.255131,070
37214.72.0.0/15214.72.0.1 to 214.73.255.254214.73.255.255131,070
38214.74.0.0/15214.74.0.1 to 214.75.255.254214.75.255.255131,070
39214.76.0.0/15214.76.0.1 to 214.77.255.254214.77.255.255131,070
40214.78.0.0/15214.78.0.1 to 214.79.255.254214.79.255.255131,070
41214.80.0.0/15214.80.0.1 to 214.81.255.254214.81.255.255131,070
42214.82.0.0/15214.82.0.1 to 214.83.255.254214.83.255.255131,070
43214.84.0.0/15214.84.0.1 to 214.85.255.254214.85.255.255131,070
44214.86.0.0/15214.86.0.1 to 214.87.255.254214.87.255.255131,070
45214.88.0.0/15214.88.0.1 to 214.89.255.254214.89.255.255131,070
46214.90.0.0/15214.90.0.1 to 214.91.255.254214.91.255.255131,070
47214.92.0.0/15214.92.0.1 to 214.93.255.254214.93.255.255131,070
48214.94.0.0/15214.94.0.1 to 214.95.255.254214.95.255.255131,070
49214.96.0.0/15214.96.0.1 to 214.97.255.254214.97.255.255131,070
50214.98.0.0/15214.98.0.1 to 214.99.255.254214.99.255.255131,070
51214.100.0.0/15214.100.0.1 to 214.101.255.254214.101.255.255131,070
52214.102.0.0/15214.102.0.1 to 214.103.255.254214.103.255.255131,070
53214.104.0.0/15214.104.0.1 to 214.105.255.254214.105.255.255131,070
54214.106.0.0/15214.106.0.1 to 214.107.255.254214.107.255.255131,070
55214.108.0.0/15214.108.0.1 to 214.109.255.254214.109.255.255131,070
56214.110.0.0/15214.110.0.1 to 214.111.255.254214.111.255.255131,070
57214.112.0.0/15214.112.0.1 to 214.113.255.254214.113.255.255131,070
58214.114.0.0/15214.114.0.1 to 214.115.255.254214.115.255.255131,070
59214.116.0.0/15214.116.0.1 to 214.117.255.254214.117.255.255131,070
60214.118.0.0/15214.118.0.1 to 214.119.255.254214.119.255.255131,070
61214.120.0.0/15214.120.0.1 to 214.121.255.254214.121.255.255131,070
62214.122.0.0/15214.122.0.1 to 214.123.255.254214.123.255.255131,070
63214.124.0.0/15214.124.0.1 to 214.125.255.254214.125.255.255131,070
64214.126.0.0/15214.126.0.1 to 214.127.255.254214.127.255.255131,070
65214.128.0.0/15214.128.0.1 to 214.129.255.254214.129.255.255131,070
66214.130.0.0/15214.130.0.1 to 214.131.255.254214.131.255.255131,070
67214.132.0.0/15214.132.0.1 to 214.133.255.254214.133.255.255131,070
68214.134.0.0/15214.134.0.1 to 214.135.255.254214.135.255.255131,070
69214.136.0.0/15214.136.0.1 to 214.137.255.254214.137.255.255131,070
70214.138.0.0/15214.138.0.1 to 214.139.255.254214.139.255.255131,070
71214.140.0.0/15214.140.0.1 to 214.141.255.254214.141.255.255131,070
72214.142.0.0/15214.142.0.1 to 214.143.255.254214.143.255.255131,070
73214.144.0.0/15214.144.0.1 to 214.145.255.254214.145.255.255131,070
74214.146.0.0/15214.146.0.1 to 214.147.255.254214.147.255.255131,070
75214.148.0.0/15214.148.0.1 to 214.149.255.254214.149.255.255131,070
76214.150.0.0/15214.150.0.1 to 214.151.255.254214.151.255.255131,070
77214.152.0.0/15214.152.0.1 to 214.153.255.254214.153.255.255131,070
78214.154.0.0/15214.154.0.1 to 214.155.255.254214.155.255.255131,070
79214.156.0.0/15214.156.0.1 to 214.157.255.254214.157.255.255131,070
80214.158.0.0/15214.158.0.1 to 214.159.255.254214.159.255.255131,070
81214.160.0.0/15214.160.0.1 to 214.161.255.254214.161.255.255131,070
82214.162.0.0/15214.162.0.1 to 214.163.255.254214.163.255.255131,070
83214.164.0.0/15214.164.0.1 to 214.165.255.254214.165.255.255131,070
84214.166.0.0/15214.166.0.1 to 214.167.255.254214.167.255.255131,070
85214.168.0.0/15214.168.0.1 to 214.169.255.254214.169.255.255131,070
86214.170.0.0/15214.170.0.1 to 214.171.255.254214.171.255.255131,070
87214.172.0.0/15214.172.0.1 to 214.173.255.254214.173.255.255131,070
88214.174.0.0/15214.174.0.1 to 214.175.255.254214.175.255.255131,070
89214.176.0.0/15214.176.0.1 to 214.177.255.254214.177.255.255131,070
90214.178.0.0/15214.178.0.1 to 214.179.255.254214.179.255.255131,070
91214.180.0.0/15214.180.0.1 to 214.181.255.254214.181.255.255131,070
92214.182.0.0/15214.182.0.1 to 214.183.255.254214.183.255.255131,070
93214.184.0.0/15214.184.0.1 to 214.185.255.254214.185.255.255131,070
94214.186.0.0/15214.186.0.1 to 214.187.255.254214.187.255.255131,070
95214.188.0.0/15214.188.0.1 to 214.189.255.254214.189.255.255131,070
96214.190.0.0/15214.190.0.1 to 214.191.255.254214.191.255.255131,070
97214.192.0.0/15214.192.0.1 to 214.193.255.254214.193.255.255131,070
98214.194.0.0/15214.194.0.1 to 214.195.255.254214.195.255.255131,070
99214.196.0.0/15214.196.0.1 to 214.197.255.254214.197.255.255131,070
100214.198.0.0/15214.198.0.1 to 214.199.255.254214.199.255.255131,070
101214.200.0.0/15214.200.0.1 to 214.201.255.254214.201.255.255131,070
102214.202.0.0/15214.202.0.1 to 214.203.255.254214.203.255.255131,070
103214.204.0.0/15214.204.0.1 to 214.205.255.254214.205.255.255131,070
104214.206.0.0/15214.206.0.1 to 214.207.255.254214.207.255.255131,070
105214.208.0.0/15214.208.0.1 to 214.209.255.254214.209.255.255131,070
106214.210.0.0/15214.210.0.1 to 214.211.255.254214.211.255.255131,070
107214.212.0.0/15214.212.0.1 to 214.213.255.254214.213.255.255131,070
108214.214.0.0/15214.214.0.1 to 214.215.255.254214.215.255.255131,070
109214.216.0.0/15214.216.0.1 to 214.217.255.254214.217.255.255131,070
110214.218.0.0/15214.218.0.1 to 214.219.255.254214.219.255.255131,070
111214.220.0.0/15214.220.0.1 to 214.221.255.254214.221.255.255131,070
112214.222.0.0/15214.222.0.1 to 214.223.255.254214.223.255.255131,070
113214.224.0.0/15214.224.0.1 to 214.225.255.254214.225.255.255131,070
114214.226.0.0/15214.226.0.1 to 214.227.255.254214.227.255.255131,070
115214.228.0.0/15214.228.0.1 to 214.229.255.254214.229.255.255131,070
116214.230.0.0/15214.230.0.1 to 214.231.255.254214.231.255.255131,070
117214.232.0.0/15214.232.0.1 to 214.233.255.254214.233.255.255131,070
118214.234.0.0/15214.234.0.1 to 214.235.255.254214.235.255.255131,070
119214.236.0.0/15214.236.0.1 to 214.237.255.254214.237.255.255131,070
120214.238.0.0/15214.238.0.1 to 214.239.255.254214.239.255.255131,070
121214.240.0.0/15214.240.0.1 to 214.241.255.254214.241.255.255131,070
122214.242.0.0/15214.242.0.1 to 214.243.255.254214.243.255.255131,070
123214.244.0.0/15214.244.0.1 to 214.245.255.254214.245.255.255131,070
124214.246.0.0/15214.246.0.1 to 214.247.255.254214.247.255.255131,070
125214.248.0.0/15214.248.0.1 to 214.249.255.254214.249.255.255131,070
126214.250.0.0/15214.250.0.1 to 214.251.255.254214.251.255.255131,070
127214.252.0.0/15214.252.0.1 to 214.253.255.254214.253.255.255131,070
128214.254.0.0/15214.254.0.1 to 214.255.255.254214.255.255.255131,070

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.