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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.

Network96.0.0.0/8
Usable hosts16,777,214
Subnet mask255.0.0.0
Addresses16,777,216
Network address
96.0.0.0
Broadcast address
96.255.255.255
First usable
96.0.0.1
Last usable
96.255.255.254
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
A (default /8)
As numbers
Hex 60000000 · Integer 1610612736 to 1627389951
Reverse DNS zone
96.in-addr.arpa
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address01100000..00000000.00000000.0000000096.0.0.0
Subnet mask11111111..00000000.00000000.00000000255.0.0.0
Network01100000..00000000.00000000.0000000096.0.0.0
Broadcast01100000..11111111.11111111.1111111196.255.255.255
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)

96.0.0.0/8 makes 128 subnets of /15.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
196.0.0.0/1596.0.0.1 to 96.1.255.25496.1.255.255131,070
296.2.0.0/1596.2.0.1 to 96.3.255.25496.3.255.255131,070
396.4.0.0/1596.4.0.1 to 96.5.255.25496.5.255.255131,070
496.6.0.0/1596.6.0.1 to 96.7.255.25496.7.255.255131,070
596.8.0.0/1596.8.0.1 to 96.9.255.25496.9.255.255131,070
696.10.0.0/1596.10.0.1 to 96.11.255.25496.11.255.255131,070
796.12.0.0/1596.12.0.1 to 96.13.255.25496.13.255.255131,070
896.14.0.0/1596.14.0.1 to 96.15.255.25496.15.255.255131,070
996.16.0.0/1596.16.0.1 to 96.17.255.25496.17.255.255131,070
1096.18.0.0/1596.18.0.1 to 96.19.255.25496.19.255.255131,070
1196.20.0.0/1596.20.0.1 to 96.21.255.25496.21.255.255131,070
1296.22.0.0/1596.22.0.1 to 96.23.255.25496.23.255.255131,070
1396.24.0.0/1596.24.0.1 to 96.25.255.25496.25.255.255131,070
1496.26.0.0/1596.26.0.1 to 96.27.255.25496.27.255.255131,070
1596.28.0.0/1596.28.0.1 to 96.29.255.25496.29.255.255131,070
1696.30.0.0/1596.30.0.1 to 96.31.255.25496.31.255.255131,070
1796.32.0.0/1596.32.0.1 to 96.33.255.25496.33.255.255131,070
1896.34.0.0/1596.34.0.1 to 96.35.255.25496.35.255.255131,070
1996.36.0.0/1596.36.0.1 to 96.37.255.25496.37.255.255131,070
2096.38.0.0/1596.38.0.1 to 96.39.255.25496.39.255.255131,070
2196.40.0.0/1596.40.0.1 to 96.41.255.25496.41.255.255131,070
2296.42.0.0/1596.42.0.1 to 96.43.255.25496.43.255.255131,070
2396.44.0.0/1596.44.0.1 to 96.45.255.25496.45.255.255131,070
2496.46.0.0/1596.46.0.1 to 96.47.255.25496.47.255.255131,070
2596.48.0.0/1596.48.0.1 to 96.49.255.25496.49.255.255131,070
2696.50.0.0/1596.50.0.1 to 96.51.255.25496.51.255.255131,070
2796.52.0.0/1596.52.0.1 to 96.53.255.25496.53.255.255131,070
2896.54.0.0/1596.54.0.1 to 96.55.255.25496.55.255.255131,070
2996.56.0.0/1596.56.0.1 to 96.57.255.25496.57.255.255131,070
3096.58.0.0/1596.58.0.1 to 96.59.255.25496.59.255.255131,070
3196.60.0.0/1596.60.0.1 to 96.61.255.25496.61.255.255131,070
3296.62.0.0/1596.62.0.1 to 96.63.255.25496.63.255.255131,070
3396.64.0.0/1596.64.0.1 to 96.65.255.25496.65.255.255131,070
3496.66.0.0/1596.66.0.1 to 96.67.255.25496.67.255.255131,070
3596.68.0.0/1596.68.0.1 to 96.69.255.25496.69.255.255131,070
3696.70.0.0/1596.70.0.1 to 96.71.255.25496.71.255.255131,070
3796.72.0.0/1596.72.0.1 to 96.73.255.25496.73.255.255131,070
3896.74.0.0/1596.74.0.1 to 96.75.255.25496.75.255.255131,070
3996.76.0.0/1596.76.0.1 to 96.77.255.25496.77.255.255131,070
4096.78.0.0/1596.78.0.1 to 96.79.255.25496.79.255.255131,070
4196.80.0.0/1596.80.0.1 to 96.81.255.25496.81.255.255131,070
4296.82.0.0/1596.82.0.1 to 96.83.255.25496.83.255.255131,070
4396.84.0.0/1596.84.0.1 to 96.85.255.25496.85.255.255131,070
4496.86.0.0/1596.86.0.1 to 96.87.255.25496.87.255.255131,070
4596.88.0.0/1596.88.0.1 to 96.89.255.25496.89.255.255131,070
4696.90.0.0/1596.90.0.1 to 96.91.255.25496.91.255.255131,070
4796.92.0.0/1596.92.0.1 to 96.93.255.25496.93.255.255131,070
4896.94.0.0/1596.94.0.1 to 96.95.255.25496.95.255.255131,070
4996.96.0.0/1596.96.0.1 to 96.97.255.25496.97.255.255131,070
5096.98.0.0/1596.98.0.1 to 96.99.255.25496.99.255.255131,070
5196.100.0.0/1596.100.0.1 to 96.101.255.25496.101.255.255131,070
5296.102.0.0/1596.102.0.1 to 96.103.255.25496.103.255.255131,070
5396.104.0.0/1596.104.0.1 to 96.105.255.25496.105.255.255131,070
5496.106.0.0/1596.106.0.1 to 96.107.255.25496.107.255.255131,070
5596.108.0.0/1596.108.0.1 to 96.109.255.25496.109.255.255131,070
5696.110.0.0/1596.110.0.1 to 96.111.255.25496.111.255.255131,070
5796.112.0.0/1596.112.0.1 to 96.113.255.25496.113.255.255131,070
5896.114.0.0/1596.114.0.1 to 96.115.255.25496.115.255.255131,070
5996.116.0.0/1596.116.0.1 to 96.117.255.25496.117.255.255131,070
6096.118.0.0/1596.118.0.1 to 96.119.255.25496.119.255.255131,070
6196.120.0.0/1596.120.0.1 to 96.121.255.25496.121.255.255131,070
6296.122.0.0/1596.122.0.1 to 96.123.255.25496.123.255.255131,070
6396.124.0.0/1596.124.0.1 to 96.125.255.25496.125.255.255131,070
6496.126.0.0/1596.126.0.1 to 96.127.255.25496.127.255.255131,070
6596.128.0.0/1596.128.0.1 to 96.129.255.25496.129.255.255131,070
6696.130.0.0/1596.130.0.1 to 96.131.255.25496.131.255.255131,070
6796.132.0.0/1596.132.0.1 to 96.133.255.25496.133.255.255131,070
6896.134.0.0/1596.134.0.1 to 96.135.255.25496.135.255.255131,070
6996.136.0.0/1596.136.0.1 to 96.137.255.25496.137.255.255131,070
7096.138.0.0/1596.138.0.1 to 96.139.255.25496.139.255.255131,070
7196.140.0.0/1596.140.0.1 to 96.141.255.25496.141.255.255131,070
7296.142.0.0/1596.142.0.1 to 96.143.255.25496.143.255.255131,070
7396.144.0.0/1596.144.0.1 to 96.145.255.25496.145.255.255131,070
7496.146.0.0/1596.146.0.1 to 96.147.255.25496.147.255.255131,070
7596.148.0.0/1596.148.0.1 to 96.149.255.25496.149.255.255131,070
7696.150.0.0/1596.150.0.1 to 96.151.255.25496.151.255.255131,070
7796.152.0.0/1596.152.0.1 to 96.153.255.25496.153.255.255131,070
7896.154.0.0/1596.154.0.1 to 96.155.255.25496.155.255.255131,070
7996.156.0.0/1596.156.0.1 to 96.157.255.25496.157.255.255131,070
8096.158.0.0/1596.158.0.1 to 96.159.255.25496.159.255.255131,070
8196.160.0.0/1596.160.0.1 to 96.161.255.25496.161.255.255131,070
8296.162.0.0/1596.162.0.1 to 96.163.255.25496.163.255.255131,070
8396.164.0.0/1596.164.0.1 to 96.165.255.25496.165.255.255131,070
8496.166.0.0/1596.166.0.1 to 96.167.255.25496.167.255.255131,070
8596.168.0.0/1596.168.0.1 to 96.169.255.25496.169.255.255131,070
8696.170.0.0/1596.170.0.1 to 96.171.255.25496.171.255.255131,070
8796.172.0.0/1596.172.0.1 to 96.173.255.25496.173.255.255131,070
8896.174.0.0/1596.174.0.1 to 96.175.255.25496.175.255.255131,070
8996.176.0.0/1596.176.0.1 to 96.177.255.25496.177.255.255131,070
9096.178.0.0/1596.178.0.1 to 96.179.255.25496.179.255.255131,070
9196.180.0.0/1596.180.0.1 to 96.181.255.25496.181.255.255131,070
9296.182.0.0/1596.182.0.1 to 96.183.255.25496.183.255.255131,070
9396.184.0.0/1596.184.0.1 to 96.185.255.25496.185.255.255131,070
9496.186.0.0/1596.186.0.1 to 96.187.255.25496.187.255.255131,070
9596.188.0.0/1596.188.0.1 to 96.189.255.25496.189.255.255131,070
9696.190.0.0/1596.190.0.1 to 96.191.255.25496.191.255.255131,070
9796.192.0.0/1596.192.0.1 to 96.193.255.25496.193.255.255131,070
9896.194.0.0/1596.194.0.1 to 96.195.255.25496.195.255.255131,070
9996.196.0.0/1596.196.0.1 to 96.197.255.25496.197.255.255131,070
10096.198.0.0/1596.198.0.1 to 96.199.255.25496.199.255.255131,070
10196.200.0.0/1596.200.0.1 to 96.201.255.25496.201.255.255131,070
10296.202.0.0/1596.202.0.1 to 96.203.255.25496.203.255.255131,070
10396.204.0.0/1596.204.0.1 to 96.205.255.25496.205.255.255131,070
10496.206.0.0/1596.206.0.1 to 96.207.255.25496.207.255.255131,070
10596.208.0.0/1596.208.0.1 to 96.209.255.25496.209.255.255131,070
10696.210.0.0/1596.210.0.1 to 96.211.255.25496.211.255.255131,070
10796.212.0.0/1596.212.0.1 to 96.213.255.25496.213.255.255131,070
10896.214.0.0/1596.214.0.1 to 96.215.255.25496.215.255.255131,070
10996.216.0.0/1596.216.0.1 to 96.217.255.25496.217.255.255131,070
11096.218.0.0/1596.218.0.1 to 96.219.255.25496.219.255.255131,070
11196.220.0.0/1596.220.0.1 to 96.221.255.25496.221.255.255131,070
11296.222.0.0/1596.222.0.1 to 96.223.255.25496.223.255.255131,070
11396.224.0.0/1596.224.0.1 to 96.225.255.25496.225.255.255131,070
11496.226.0.0/1596.226.0.1 to 96.227.255.25496.227.255.255131,070
11596.228.0.0/1596.228.0.1 to 96.229.255.25496.229.255.255131,070
11696.230.0.0/1596.230.0.1 to 96.231.255.25496.231.255.255131,070
11796.232.0.0/1596.232.0.1 to 96.233.255.25496.233.255.255131,070
11896.234.0.0/1596.234.0.1 to 96.235.255.25496.235.255.255131,070
11996.236.0.0/1596.236.0.1 to 96.237.255.25496.237.255.255131,070
12096.238.0.0/1596.238.0.1 to 96.239.255.25496.239.255.255131,070
12196.240.0.0/1596.240.0.1 to 96.241.255.25496.241.255.255131,070
12296.242.0.0/1596.242.0.1 to 96.243.255.25496.243.255.255131,070
12396.244.0.0/1596.244.0.1 to 96.245.255.25496.245.255.255131,070
12496.246.0.0/1596.246.0.1 to 96.247.255.25496.247.255.255131,070
12596.248.0.0/1596.248.0.1 to 96.249.255.25496.249.255.255131,070
12696.250.0.0/1596.250.0.1 to 96.251.255.25496.251.255.255131,070
12796.252.0.0/1596.252.0.1 to 96.253.255.25496.253.255.255131,070
12896.254.0.0/1596.254.0.1 to 96.255.255.25496.255.255.255131,070

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.