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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.

Network55.2.192.0/19
Usable hosts8,190
Subnet mask255.255.224.0
Addresses8,192
Network address
55.2.192.0
Broadcast address
55.2.223.255
First usable
55.2.192.1
Last usable
55.2.223.254
Usable hosts
8,190 (8,192 less the network and broadcast addresses)
Subnet mask
255.255.224.0
Wildcard mask
0.0.31.255 (Cisco ACLs, OSPF)
Prefix length
/19
Type
Public public
Old class
A (default /8)
As numbers
Hex 3702C000 · Integer 922927104 to 922935295
Reverse DNS zones
192.2.55.in-addr.arpa
193.2.55.in-addr.arpa
194.2.55.in-addr.arpa
195.2.55.in-addr.arpa
196.2.55.in-addr.arpa
197.2.55.in-addr.arpa
198.2.55.in-addr.arpa
199.2.55.in-addr.arpa
200.2.55.in-addr.arpa
201.2.55.in-addr.arpa
202.2.55.in-addr.arpa
203.2.55.in-addr.arpa
204.2.55.in-addr.arpa
205.2.55.in-addr.arpa
206.2.55.in-addr.arpa
207.2.55.in-addr.arpa
and 16 more
/19 is not on a 8-bit boundary, so it takes 32 /24 zones.
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address00110111.00000010.11000000.0000000055.2.192.0
Subnet mask11111111.11111111.11100000.00000000255.255.224.0
Network00110111.00000010.11000000.0000000055.2.192.0
Broadcast00110111.00000010.11011111.1111111155.2.223.255
Split into smaller subnets/26

55.2.192.0/19 makes 128 subnets of /26.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
155.2.192.0/2655.2.192.1 to 55.2.192.6255.2.192.6362
255.2.192.64/2655.2.192.65 to 55.2.192.12655.2.192.12762
355.2.192.128/2655.2.192.129 to 55.2.192.19055.2.192.19162
455.2.192.192/2655.2.192.193 to 55.2.192.25455.2.192.25562
555.2.193.0/2655.2.193.1 to 55.2.193.6255.2.193.6362
655.2.193.64/2655.2.193.65 to 55.2.193.12655.2.193.12762
755.2.193.128/2655.2.193.129 to 55.2.193.19055.2.193.19162
855.2.193.192/2655.2.193.193 to 55.2.193.25455.2.193.25562
955.2.194.0/2655.2.194.1 to 55.2.194.6255.2.194.6362
1055.2.194.64/2655.2.194.65 to 55.2.194.12655.2.194.12762
1155.2.194.128/2655.2.194.129 to 55.2.194.19055.2.194.19162
1255.2.194.192/2655.2.194.193 to 55.2.194.25455.2.194.25562
1355.2.195.0/2655.2.195.1 to 55.2.195.6255.2.195.6362
1455.2.195.64/2655.2.195.65 to 55.2.195.12655.2.195.12762
1555.2.195.128/2655.2.195.129 to 55.2.195.19055.2.195.19162
1655.2.195.192/2655.2.195.193 to 55.2.195.25455.2.195.25562
1755.2.196.0/2655.2.196.1 to 55.2.196.6255.2.196.6362
1855.2.196.64/2655.2.196.65 to 55.2.196.12655.2.196.12762
1955.2.196.128/2655.2.196.129 to 55.2.196.19055.2.196.19162
2055.2.196.192/2655.2.196.193 to 55.2.196.25455.2.196.25562
2155.2.197.0/2655.2.197.1 to 55.2.197.6255.2.197.6362
2255.2.197.64/2655.2.197.65 to 55.2.197.12655.2.197.12762
2355.2.197.128/2655.2.197.129 to 55.2.197.19055.2.197.19162
2455.2.197.192/2655.2.197.193 to 55.2.197.25455.2.197.25562
2555.2.198.0/2655.2.198.1 to 55.2.198.6255.2.198.6362
2655.2.198.64/2655.2.198.65 to 55.2.198.12655.2.198.12762
2755.2.198.128/2655.2.198.129 to 55.2.198.19055.2.198.19162
2855.2.198.192/2655.2.198.193 to 55.2.198.25455.2.198.25562
2955.2.199.0/2655.2.199.1 to 55.2.199.6255.2.199.6362
3055.2.199.64/2655.2.199.65 to 55.2.199.12655.2.199.12762
3155.2.199.128/2655.2.199.129 to 55.2.199.19055.2.199.19162
3255.2.199.192/2655.2.199.193 to 55.2.199.25455.2.199.25562
3355.2.200.0/2655.2.200.1 to 55.2.200.6255.2.200.6362
3455.2.200.64/2655.2.200.65 to 55.2.200.12655.2.200.12762
3555.2.200.128/2655.2.200.129 to 55.2.200.19055.2.200.19162
3655.2.200.192/2655.2.200.193 to 55.2.200.25455.2.200.25562
3755.2.201.0/2655.2.201.1 to 55.2.201.6255.2.201.6362
3855.2.201.64/2655.2.201.65 to 55.2.201.12655.2.201.12762
3955.2.201.128/2655.2.201.129 to 55.2.201.19055.2.201.19162
4055.2.201.192/2655.2.201.193 to 55.2.201.25455.2.201.25562
4155.2.202.0/2655.2.202.1 to 55.2.202.6255.2.202.6362
4255.2.202.64/2655.2.202.65 to 55.2.202.12655.2.202.12762
4355.2.202.128/2655.2.202.129 to 55.2.202.19055.2.202.19162
4455.2.202.192/2655.2.202.193 to 55.2.202.25455.2.202.25562
4555.2.203.0/2655.2.203.1 to 55.2.203.6255.2.203.6362
4655.2.203.64/2655.2.203.65 to 55.2.203.12655.2.203.12762
4755.2.203.128/2655.2.203.129 to 55.2.203.19055.2.203.19162
4855.2.203.192/2655.2.203.193 to 55.2.203.25455.2.203.25562
4955.2.204.0/2655.2.204.1 to 55.2.204.6255.2.204.6362
5055.2.204.64/2655.2.204.65 to 55.2.204.12655.2.204.12762
5155.2.204.128/2655.2.204.129 to 55.2.204.19055.2.204.19162
5255.2.204.192/2655.2.204.193 to 55.2.204.25455.2.204.25562
5355.2.205.0/2655.2.205.1 to 55.2.205.6255.2.205.6362
5455.2.205.64/2655.2.205.65 to 55.2.205.12655.2.205.12762
5555.2.205.128/2655.2.205.129 to 55.2.205.19055.2.205.19162
5655.2.205.192/2655.2.205.193 to 55.2.205.25455.2.205.25562
5755.2.206.0/2655.2.206.1 to 55.2.206.6255.2.206.6362
5855.2.206.64/2655.2.206.65 to 55.2.206.12655.2.206.12762
5955.2.206.128/2655.2.206.129 to 55.2.206.19055.2.206.19162
6055.2.206.192/2655.2.206.193 to 55.2.206.25455.2.206.25562
6155.2.207.0/2655.2.207.1 to 55.2.207.6255.2.207.6362
6255.2.207.64/2655.2.207.65 to 55.2.207.12655.2.207.12762
6355.2.207.128/2655.2.207.129 to 55.2.207.19055.2.207.19162
6455.2.207.192/2655.2.207.193 to 55.2.207.25455.2.207.25562
6555.2.208.0/2655.2.208.1 to 55.2.208.6255.2.208.6362
6655.2.208.64/2655.2.208.65 to 55.2.208.12655.2.208.12762
6755.2.208.128/2655.2.208.129 to 55.2.208.19055.2.208.19162
6855.2.208.192/2655.2.208.193 to 55.2.208.25455.2.208.25562
6955.2.209.0/2655.2.209.1 to 55.2.209.6255.2.209.6362
7055.2.209.64/2655.2.209.65 to 55.2.209.12655.2.209.12762
7155.2.209.128/2655.2.209.129 to 55.2.209.19055.2.209.19162
7255.2.209.192/2655.2.209.193 to 55.2.209.25455.2.209.25562
7355.2.210.0/2655.2.210.1 to 55.2.210.6255.2.210.6362
7455.2.210.64/2655.2.210.65 to 55.2.210.12655.2.210.12762
7555.2.210.128/2655.2.210.129 to 55.2.210.19055.2.210.19162
7655.2.210.192/2655.2.210.193 to 55.2.210.25455.2.210.25562
7755.2.211.0/2655.2.211.1 to 55.2.211.6255.2.211.6362
7855.2.211.64/2655.2.211.65 to 55.2.211.12655.2.211.12762
7955.2.211.128/2655.2.211.129 to 55.2.211.19055.2.211.19162
8055.2.211.192/2655.2.211.193 to 55.2.211.25455.2.211.25562
8155.2.212.0/2655.2.212.1 to 55.2.212.6255.2.212.6362
8255.2.212.64/2655.2.212.65 to 55.2.212.12655.2.212.12762
8355.2.212.128/2655.2.212.129 to 55.2.212.19055.2.212.19162
8455.2.212.192/2655.2.212.193 to 55.2.212.25455.2.212.25562
8555.2.213.0/2655.2.213.1 to 55.2.213.6255.2.213.6362
8655.2.213.64/2655.2.213.65 to 55.2.213.12655.2.213.12762
8755.2.213.128/2655.2.213.129 to 55.2.213.19055.2.213.19162
8855.2.213.192/2655.2.213.193 to 55.2.213.25455.2.213.25562
8955.2.214.0/2655.2.214.1 to 55.2.214.6255.2.214.6362
9055.2.214.64/2655.2.214.65 to 55.2.214.12655.2.214.12762
9155.2.214.128/2655.2.214.129 to 55.2.214.19055.2.214.19162
9255.2.214.192/2655.2.214.193 to 55.2.214.25455.2.214.25562
9355.2.215.0/2655.2.215.1 to 55.2.215.6255.2.215.6362
9455.2.215.64/2655.2.215.65 to 55.2.215.12655.2.215.12762
9555.2.215.128/2655.2.215.129 to 55.2.215.19055.2.215.19162
9655.2.215.192/2655.2.215.193 to 55.2.215.25455.2.215.25562
9755.2.216.0/2655.2.216.1 to 55.2.216.6255.2.216.6362
9855.2.216.64/2655.2.216.65 to 55.2.216.12655.2.216.12762
9955.2.216.128/2655.2.216.129 to 55.2.216.19055.2.216.19162
10055.2.216.192/2655.2.216.193 to 55.2.216.25455.2.216.25562
10155.2.217.0/2655.2.217.1 to 55.2.217.6255.2.217.6362
10255.2.217.64/2655.2.217.65 to 55.2.217.12655.2.217.12762
10355.2.217.128/2655.2.217.129 to 55.2.217.19055.2.217.19162
10455.2.217.192/2655.2.217.193 to 55.2.217.25455.2.217.25562
10555.2.218.0/2655.2.218.1 to 55.2.218.6255.2.218.6362
10655.2.218.64/2655.2.218.65 to 55.2.218.12655.2.218.12762
10755.2.218.128/2655.2.218.129 to 55.2.218.19055.2.218.19162
10855.2.218.192/2655.2.218.193 to 55.2.218.25455.2.218.25562
10955.2.219.0/2655.2.219.1 to 55.2.219.6255.2.219.6362
11055.2.219.64/2655.2.219.65 to 55.2.219.12655.2.219.12762
11155.2.219.128/2655.2.219.129 to 55.2.219.19055.2.219.19162
11255.2.219.192/2655.2.219.193 to 55.2.219.25455.2.219.25562
11355.2.220.0/2655.2.220.1 to 55.2.220.6255.2.220.6362
11455.2.220.64/2655.2.220.65 to 55.2.220.12655.2.220.12762
11555.2.220.128/2655.2.220.129 to 55.2.220.19055.2.220.19162
11655.2.220.192/2655.2.220.193 to 55.2.220.25455.2.220.25562
11755.2.221.0/2655.2.221.1 to 55.2.221.6255.2.221.6362
11855.2.221.64/2655.2.221.65 to 55.2.221.12655.2.221.12762
11955.2.221.128/2655.2.221.129 to 55.2.221.19055.2.221.19162
12055.2.221.192/2655.2.221.193 to 55.2.221.25455.2.221.25562
12155.2.222.0/2655.2.222.1 to 55.2.222.6255.2.222.6362
12255.2.222.64/2655.2.222.65 to 55.2.222.12655.2.222.12762
12355.2.222.128/2655.2.222.129 to 55.2.222.19055.2.222.19162
12455.2.222.192/2655.2.222.193 to 55.2.222.25455.2.222.25562
12555.2.223.0/2655.2.223.1 to 55.2.223.6255.2.223.6362
12655.2.223.64/2655.2.223.65 to 55.2.223.12655.2.223.12762
12755.2.223.128/2655.2.223.129 to 55.2.223.19055.2.223.19162
12855.2.223.192/2655.2.223.193 to 55.2.223.25455.2.223.25562

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