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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.

Network22.160.0.0/11
Usable hosts2,097,150
Subnet mask255.224.0.0
Addresses2,097,152
Network address
22.160.0.0
Broadcast address
22.191.255.255
First usable
22.160.0.1
Last usable
22.191.255.254
Usable hosts
2,097,150 (2,097,152 less the network and broadcast addresses)
Subnet mask
255.224.0.0
Wildcard mask
0.31.255.255 (Cisco ACLs, OSPF)
Prefix length
/11
Type
Public public
Old class
A (default /8)
As numbers
Hex 16A00000 · Integer 379584512 to 381681663
Reverse DNS zones
160.22.in-addr.arpa
161.22.in-addr.arpa
162.22.in-addr.arpa
163.22.in-addr.arpa
164.22.in-addr.arpa
165.22.in-addr.arpa
166.22.in-addr.arpa
167.22.in-addr.arpa
168.22.in-addr.arpa
169.22.in-addr.arpa
170.22.in-addr.arpa
171.22.in-addr.arpa
172.22.in-addr.arpa
173.22.in-addr.arpa
174.22.in-addr.arpa
175.22.in-addr.arpa
and 16 more
/11 is not on a 8-bit boundary, so it takes 32 /16 zones.
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address00010110.10100000.00000000.0000000022.160.0.0
Subnet mask11111111.11100000.00000000.00000000255.224.0.0
Network00010110.10100000.00000000.0000000022.160.0.0
Broadcast00010110.10111111.11111111.1111111122.191.255.255
Split into smaller subnets/18
/12 (2)/13 (4)/14 (8)/15 (16)/16 (32)/17 (64)/18 (128)/19 (256)/20 (512)/21 (1,024)/22 (2,048)/23 (4,096)

22.160.0.0/11 makes 128 subnets of /18.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
122.160.0.0/1822.160.0.1 to 22.160.63.25422.160.63.25516,382
222.160.64.0/1822.160.64.1 to 22.160.127.25422.160.127.25516,382
322.160.128.0/1822.160.128.1 to 22.160.191.25422.160.191.25516,382
422.160.192.0/1822.160.192.1 to 22.160.255.25422.160.255.25516,382
522.161.0.0/1822.161.0.1 to 22.161.63.25422.161.63.25516,382
622.161.64.0/1822.161.64.1 to 22.161.127.25422.161.127.25516,382
722.161.128.0/1822.161.128.1 to 22.161.191.25422.161.191.25516,382
822.161.192.0/1822.161.192.1 to 22.161.255.25422.161.255.25516,382
922.162.0.0/1822.162.0.1 to 22.162.63.25422.162.63.25516,382
1022.162.64.0/1822.162.64.1 to 22.162.127.25422.162.127.25516,382
1122.162.128.0/1822.162.128.1 to 22.162.191.25422.162.191.25516,382
1222.162.192.0/1822.162.192.1 to 22.162.255.25422.162.255.25516,382
1322.163.0.0/1822.163.0.1 to 22.163.63.25422.163.63.25516,382
1422.163.64.0/1822.163.64.1 to 22.163.127.25422.163.127.25516,382
1522.163.128.0/1822.163.128.1 to 22.163.191.25422.163.191.25516,382
1622.163.192.0/1822.163.192.1 to 22.163.255.25422.163.255.25516,382
1722.164.0.0/1822.164.0.1 to 22.164.63.25422.164.63.25516,382
1822.164.64.0/1822.164.64.1 to 22.164.127.25422.164.127.25516,382
1922.164.128.0/1822.164.128.1 to 22.164.191.25422.164.191.25516,382
2022.164.192.0/1822.164.192.1 to 22.164.255.25422.164.255.25516,382
2122.165.0.0/1822.165.0.1 to 22.165.63.25422.165.63.25516,382
2222.165.64.0/1822.165.64.1 to 22.165.127.25422.165.127.25516,382
2322.165.128.0/1822.165.128.1 to 22.165.191.25422.165.191.25516,382
2422.165.192.0/1822.165.192.1 to 22.165.255.25422.165.255.25516,382
2522.166.0.0/1822.166.0.1 to 22.166.63.25422.166.63.25516,382
2622.166.64.0/1822.166.64.1 to 22.166.127.25422.166.127.25516,382
2722.166.128.0/1822.166.128.1 to 22.166.191.25422.166.191.25516,382
2822.166.192.0/1822.166.192.1 to 22.166.255.25422.166.255.25516,382
2922.167.0.0/1822.167.0.1 to 22.167.63.25422.167.63.25516,382
3022.167.64.0/1822.167.64.1 to 22.167.127.25422.167.127.25516,382
3122.167.128.0/1822.167.128.1 to 22.167.191.25422.167.191.25516,382
3222.167.192.0/1822.167.192.1 to 22.167.255.25422.167.255.25516,382
3322.168.0.0/1822.168.0.1 to 22.168.63.25422.168.63.25516,382
3422.168.64.0/1822.168.64.1 to 22.168.127.25422.168.127.25516,382
3522.168.128.0/1822.168.128.1 to 22.168.191.25422.168.191.25516,382
3622.168.192.0/1822.168.192.1 to 22.168.255.25422.168.255.25516,382
3722.169.0.0/1822.169.0.1 to 22.169.63.25422.169.63.25516,382
3822.169.64.0/1822.169.64.1 to 22.169.127.25422.169.127.25516,382
3922.169.128.0/1822.169.128.1 to 22.169.191.25422.169.191.25516,382
4022.169.192.0/1822.169.192.1 to 22.169.255.25422.169.255.25516,382
4122.170.0.0/1822.170.0.1 to 22.170.63.25422.170.63.25516,382
4222.170.64.0/1822.170.64.1 to 22.170.127.25422.170.127.25516,382
4322.170.128.0/1822.170.128.1 to 22.170.191.25422.170.191.25516,382
4422.170.192.0/1822.170.192.1 to 22.170.255.25422.170.255.25516,382
4522.171.0.0/1822.171.0.1 to 22.171.63.25422.171.63.25516,382
4622.171.64.0/1822.171.64.1 to 22.171.127.25422.171.127.25516,382
4722.171.128.0/1822.171.128.1 to 22.171.191.25422.171.191.25516,382
4822.171.192.0/1822.171.192.1 to 22.171.255.25422.171.255.25516,382
4922.172.0.0/1822.172.0.1 to 22.172.63.25422.172.63.25516,382
5022.172.64.0/1822.172.64.1 to 22.172.127.25422.172.127.25516,382
5122.172.128.0/1822.172.128.1 to 22.172.191.25422.172.191.25516,382
5222.172.192.0/1822.172.192.1 to 22.172.255.25422.172.255.25516,382
5322.173.0.0/1822.173.0.1 to 22.173.63.25422.173.63.25516,382
5422.173.64.0/1822.173.64.1 to 22.173.127.25422.173.127.25516,382
5522.173.128.0/1822.173.128.1 to 22.173.191.25422.173.191.25516,382
5622.173.192.0/1822.173.192.1 to 22.173.255.25422.173.255.25516,382
5722.174.0.0/1822.174.0.1 to 22.174.63.25422.174.63.25516,382
5822.174.64.0/1822.174.64.1 to 22.174.127.25422.174.127.25516,382
5922.174.128.0/1822.174.128.1 to 22.174.191.25422.174.191.25516,382
6022.174.192.0/1822.174.192.1 to 22.174.255.25422.174.255.25516,382
6122.175.0.0/1822.175.0.1 to 22.175.63.25422.175.63.25516,382
6222.175.64.0/1822.175.64.1 to 22.175.127.25422.175.127.25516,382
6322.175.128.0/1822.175.128.1 to 22.175.191.25422.175.191.25516,382
6422.175.192.0/1822.175.192.1 to 22.175.255.25422.175.255.25516,382
6522.176.0.0/1822.176.0.1 to 22.176.63.25422.176.63.25516,382
6622.176.64.0/1822.176.64.1 to 22.176.127.25422.176.127.25516,382
6722.176.128.0/1822.176.128.1 to 22.176.191.25422.176.191.25516,382
6822.176.192.0/1822.176.192.1 to 22.176.255.25422.176.255.25516,382
6922.177.0.0/1822.177.0.1 to 22.177.63.25422.177.63.25516,382
7022.177.64.0/1822.177.64.1 to 22.177.127.25422.177.127.25516,382
7122.177.128.0/1822.177.128.1 to 22.177.191.25422.177.191.25516,382
7222.177.192.0/1822.177.192.1 to 22.177.255.25422.177.255.25516,382
7322.178.0.0/1822.178.0.1 to 22.178.63.25422.178.63.25516,382
7422.178.64.0/1822.178.64.1 to 22.178.127.25422.178.127.25516,382
7522.178.128.0/1822.178.128.1 to 22.178.191.25422.178.191.25516,382
7622.178.192.0/1822.178.192.1 to 22.178.255.25422.178.255.25516,382
7722.179.0.0/1822.179.0.1 to 22.179.63.25422.179.63.25516,382
7822.179.64.0/1822.179.64.1 to 22.179.127.25422.179.127.25516,382
7922.179.128.0/1822.179.128.1 to 22.179.191.25422.179.191.25516,382
8022.179.192.0/1822.179.192.1 to 22.179.255.25422.179.255.25516,382
8122.180.0.0/1822.180.0.1 to 22.180.63.25422.180.63.25516,382
8222.180.64.0/1822.180.64.1 to 22.180.127.25422.180.127.25516,382
8322.180.128.0/1822.180.128.1 to 22.180.191.25422.180.191.25516,382
8422.180.192.0/1822.180.192.1 to 22.180.255.25422.180.255.25516,382
8522.181.0.0/1822.181.0.1 to 22.181.63.25422.181.63.25516,382
8622.181.64.0/1822.181.64.1 to 22.181.127.25422.181.127.25516,382
8722.181.128.0/1822.181.128.1 to 22.181.191.25422.181.191.25516,382
8822.181.192.0/1822.181.192.1 to 22.181.255.25422.181.255.25516,382
8922.182.0.0/1822.182.0.1 to 22.182.63.25422.182.63.25516,382
9022.182.64.0/1822.182.64.1 to 22.182.127.25422.182.127.25516,382
9122.182.128.0/1822.182.128.1 to 22.182.191.25422.182.191.25516,382
9222.182.192.0/1822.182.192.1 to 22.182.255.25422.182.255.25516,382
9322.183.0.0/1822.183.0.1 to 22.183.63.25422.183.63.25516,382
9422.183.64.0/1822.183.64.1 to 22.183.127.25422.183.127.25516,382
9522.183.128.0/1822.183.128.1 to 22.183.191.25422.183.191.25516,382
9622.183.192.0/1822.183.192.1 to 22.183.255.25422.183.255.25516,382
9722.184.0.0/1822.184.0.1 to 22.184.63.25422.184.63.25516,382
9822.184.64.0/1822.184.64.1 to 22.184.127.25422.184.127.25516,382
9922.184.128.0/1822.184.128.1 to 22.184.191.25422.184.191.25516,382
10022.184.192.0/1822.184.192.1 to 22.184.255.25422.184.255.25516,382
10122.185.0.0/1822.185.0.1 to 22.185.63.25422.185.63.25516,382
10222.185.64.0/1822.185.64.1 to 22.185.127.25422.185.127.25516,382
10322.185.128.0/1822.185.128.1 to 22.185.191.25422.185.191.25516,382
10422.185.192.0/1822.185.192.1 to 22.185.255.25422.185.255.25516,382
10522.186.0.0/1822.186.0.1 to 22.186.63.25422.186.63.25516,382
10622.186.64.0/1822.186.64.1 to 22.186.127.25422.186.127.25516,382
10722.186.128.0/1822.186.128.1 to 22.186.191.25422.186.191.25516,382
10822.186.192.0/1822.186.192.1 to 22.186.255.25422.186.255.25516,382
10922.187.0.0/1822.187.0.1 to 22.187.63.25422.187.63.25516,382
11022.187.64.0/1822.187.64.1 to 22.187.127.25422.187.127.25516,382
11122.187.128.0/1822.187.128.1 to 22.187.191.25422.187.191.25516,382
11222.187.192.0/1822.187.192.1 to 22.187.255.25422.187.255.25516,382
11322.188.0.0/1822.188.0.1 to 22.188.63.25422.188.63.25516,382
11422.188.64.0/1822.188.64.1 to 22.188.127.25422.188.127.25516,382
11522.188.128.0/1822.188.128.1 to 22.188.191.25422.188.191.25516,382
11622.188.192.0/1822.188.192.1 to 22.188.255.25422.188.255.25516,382
11722.189.0.0/1822.189.0.1 to 22.189.63.25422.189.63.25516,382
11822.189.64.0/1822.189.64.1 to 22.189.127.25422.189.127.25516,382
11922.189.128.0/1822.189.128.1 to 22.189.191.25422.189.191.25516,382
12022.189.192.0/1822.189.192.1 to 22.189.255.25422.189.255.25516,382
12122.190.0.0/1822.190.0.1 to 22.190.63.25422.190.63.25516,382
12222.190.64.0/1822.190.64.1 to 22.190.127.25422.190.127.25516,382
12322.190.128.0/1822.190.128.1 to 22.190.191.25422.190.191.25516,382
12422.190.192.0/1822.190.192.1 to 22.190.255.25422.190.255.25516,382
12522.191.0.0/1822.191.0.1 to 22.191.63.25422.191.63.25516,382
12622.191.64.0/1822.191.64.1 to 22.191.127.25422.191.127.25516,382
12722.191.128.0/1822.191.128.1 to 22.191.191.25422.191.191.25516,382
12822.191.192.0/1822.191.192.1 to 22.191.255.25422.191.255.25516,382

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.