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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.

Network94.26.32.0/19
Usable hosts8,190
Subnet mask255.255.224.0
Addresses8,192
Network address
94.26.32.0
Broadcast address
94.26.63.255
First usable
94.26.32.1
Last usable
94.26.63.254
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 5E1A2000 · Integer 1578770432 to 1578778623
Reverse DNS zones
32.26.94.in-addr.arpa
33.26.94.in-addr.arpa
34.26.94.in-addr.arpa
35.26.94.in-addr.arpa
36.26.94.in-addr.arpa
37.26.94.in-addr.arpa
38.26.94.in-addr.arpa
39.26.94.in-addr.arpa
40.26.94.in-addr.arpa
41.26.94.in-addr.arpa
42.26.94.in-addr.arpa
43.26.94.in-addr.arpa
44.26.94.in-addr.arpa
45.26.94.in-addr.arpa
46.26.94.in-addr.arpa
47.26.94.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
Address01011110.00011010.00100000.0000000094.26.32.0
Subnet mask11111111.11111111.11100000.00000000255.255.224.0
Network01011110.00011010.00100000.0000000094.26.32.0
Broadcast01011110.00011010.00111111.1111111194.26.63.255
Split into smaller subnets/26
/20 (2)/21 (4)/22 (8)/23 (16)/24 (32)/25 (64)/26 (128)/27 (256)/28 (512)/29 (1,024)/30 (2,048)/31 (4,096)

94.26.32.0/19 makes 128 subnets of /26.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
194.26.32.0/2694.26.32.1 to 94.26.32.6294.26.32.6362
294.26.32.64/2694.26.32.65 to 94.26.32.12694.26.32.12762
394.26.32.128/2694.26.32.129 to 94.26.32.19094.26.32.19162
494.26.32.192/2694.26.32.193 to 94.26.32.25494.26.32.25562
594.26.33.0/2694.26.33.1 to 94.26.33.6294.26.33.6362
694.26.33.64/2694.26.33.65 to 94.26.33.12694.26.33.12762
794.26.33.128/2694.26.33.129 to 94.26.33.19094.26.33.19162
894.26.33.192/2694.26.33.193 to 94.26.33.25494.26.33.25562
994.26.34.0/2694.26.34.1 to 94.26.34.6294.26.34.6362
1094.26.34.64/2694.26.34.65 to 94.26.34.12694.26.34.12762
1194.26.34.128/2694.26.34.129 to 94.26.34.19094.26.34.19162
1294.26.34.192/2694.26.34.193 to 94.26.34.25494.26.34.25562
1394.26.35.0/2694.26.35.1 to 94.26.35.6294.26.35.6362
1494.26.35.64/2694.26.35.65 to 94.26.35.12694.26.35.12762
1594.26.35.128/2694.26.35.129 to 94.26.35.19094.26.35.19162
1694.26.35.192/2694.26.35.193 to 94.26.35.25494.26.35.25562
1794.26.36.0/2694.26.36.1 to 94.26.36.6294.26.36.6362
1894.26.36.64/2694.26.36.65 to 94.26.36.12694.26.36.12762
1994.26.36.128/2694.26.36.129 to 94.26.36.19094.26.36.19162
2094.26.36.192/2694.26.36.193 to 94.26.36.25494.26.36.25562
2194.26.37.0/2694.26.37.1 to 94.26.37.6294.26.37.6362
2294.26.37.64/2694.26.37.65 to 94.26.37.12694.26.37.12762
2394.26.37.128/2694.26.37.129 to 94.26.37.19094.26.37.19162
2494.26.37.192/2694.26.37.193 to 94.26.37.25494.26.37.25562
2594.26.38.0/2694.26.38.1 to 94.26.38.6294.26.38.6362
2694.26.38.64/2694.26.38.65 to 94.26.38.12694.26.38.12762
2794.26.38.128/2694.26.38.129 to 94.26.38.19094.26.38.19162
2894.26.38.192/2694.26.38.193 to 94.26.38.25494.26.38.25562
2994.26.39.0/2694.26.39.1 to 94.26.39.6294.26.39.6362
3094.26.39.64/2694.26.39.65 to 94.26.39.12694.26.39.12762
3194.26.39.128/2694.26.39.129 to 94.26.39.19094.26.39.19162
3294.26.39.192/2694.26.39.193 to 94.26.39.25494.26.39.25562
3394.26.40.0/2694.26.40.1 to 94.26.40.6294.26.40.6362
3494.26.40.64/2694.26.40.65 to 94.26.40.12694.26.40.12762
3594.26.40.128/2694.26.40.129 to 94.26.40.19094.26.40.19162
3694.26.40.192/2694.26.40.193 to 94.26.40.25494.26.40.25562
3794.26.41.0/2694.26.41.1 to 94.26.41.6294.26.41.6362
3894.26.41.64/2694.26.41.65 to 94.26.41.12694.26.41.12762
3994.26.41.128/2694.26.41.129 to 94.26.41.19094.26.41.19162
4094.26.41.192/2694.26.41.193 to 94.26.41.25494.26.41.25562
4194.26.42.0/2694.26.42.1 to 94.26.42.6294.26.42.6362
4294.26.42.64/2694.26.42.65 to 94.26.42.12694.26.42.12762
4394.26.42.128/2694.26.42.129 to 94.26.42.19094.26.42.19162
4494.26.42.192/2694.26.42.193 to 94.26.42.25494.26.42.25562
4594.26.43.0/2694.26.43.1 to 94.26.43.6294.26.43.6362
4694.26.43.64/2694.26.43.65 to 94.26.43.12694.26.43.12762
4794.26.43.128/2694.26.43.129 to 94.26.43.19094.26.43.19162
4894.26.43.192/2694.26.43.193 to 94.26.43.25494.26.43.25562
4994.26.44.0/2694.26.44.1 to 94.26.44.6294.26.44.6362
5094.26.44.64/2694.26.44.65 to 94.26.44.12694.26.44.12762
5194.26.44.128/2694.26.44.129 to 94.26.44.19094.26.44.19162
5294.26.44.192/2694.26.44.193 to 94.26.44.25494.26.44.25562
5394.26.45.0/2694.26.45.1 to 94.26.45.6294.26.45.6362
5494.26.45.64/2694.26.45.65 to 94.26.45.12694.26.45.12762
5594.26.45.128/2694.26.45.129 to 94.26.45.19094.26.45.19162
5694.26.45.192/2694.26.45.193 to 94.26.45.25494.26.45.25562
5794.26.46.0/2694.26.46.1 to 94.26.46.6294.26.46.6362
5894.26.46.64/2694.26.46.65 to 94.26.46.12694.26.46.12762
5994.26.46.128/2694.26.46.129 to 94.26.46.19094.26.46.19162
6094.26.46.192/2694.26.46.193 to 94.26.46.25494.26.46.25562
6194.26.47.0/2694.26.47.1 to 94.26.47.6294.26.47.6362
6294.26.47.64/2694.26.47.65 to 94.26.47.12694.26.47.12762
6394.26.47.128/2694.26.47.129 to 94.26.47.19094.26.47.19162
6494.26.47.192/2694.26.47.193 to 94.26.47.25494.26.47.25562
6594.26.48.0/2694.26.48.1 to 94.26.48.6294.26.48.6362
6694.26.48.64/2694.26.48.65 to 94.26.48.12694.26.48.12762
6794.26.48.128/2694.26.48.129 to 94.26.48.19094.26.48.19162
6894.26.48.192/2694.26.48.193 to 94.26.48.25494.26.48.25562
6994.26.49.0/2694.26.49.1 to 94.26.49.6294.26.49.6362
7094.26.49.64/2694.26.49.65 to 94.26.49.12694.26.49.12762
7194.26.49.128/2694.26.49.129 to 94.26.49.19094.26.49.19162
7294.26.49.192/2694.26.49.193 to 94.26.49.25494.26.49.25562
7394.26.50.0/2694.26.50.1 to 94.26.50.6294.26.50.6362
7494.26.50.64/2694.26.50.65 to 94.26.50.12694.26.50.12762
7594.26.50.128/2694.26.50.129 to 94.26.50.19094.26.50.19162
7694.26.50.192/2694.26.50.193 to 94.26.50.25494.26.50.25562
7794.26.51.0/2694.26.51.1 to 94.26.51.6294.26.51.6362
7894.26.51.64/2694.26.51.65 to 94.26.51.12694.26.51.12762
7994.26.51.128/2694.26.51.129 to 94.26.51.19094.26.51.19162
8094.26.51.192/2694.26.51.193 to 94.26.51.25494.26.51.25562
8194.26.52.0/2694.26.52.1 to 94.26.52.6294.26.52.6362
8294.26.52.64/2694.26.52.65 to 94.26.52.12694.26.52.12762
8394.26.52.128/2694.26.52.129 to 94.26.52.19094.26.52.19162
8494.26.52.192/2694.26.52.193 to 94.26.52.25494.26.52.25562
8594.26.53.0/2694.26.53.1 to 94.26.53.6294.26.53.6362
8694.26.53.64/2694.26.53.65 to 94.26.53.12694.26.53.12762
8794.26.53.128/2694.26.53.129 to 94.26.53.19094.26.53.19162
8894.26.53.192/2694.26.53.193 to 94.26.53.25494.26.53.25562
8994.26.54.0/2694.26.54.1 to 94.26.54.6294.26.54.6362
9094.26.54.64/2694.26.54.65 to 94.26.54.12694.26.54.12762
9194.26.54.128/2694.26.54.129 to 94.26.54.19094.26.54.19162
9294.26.54.192/2694.26.54.193 to 94.26.54.25494.26.54.25562
9394.26.55.0/2694.26.55.1 to 94.26.55.6294.26.55.6362
9494.26.55.64/2694.26.55.65 to 94.26.55.12694.26.55.12762
9594.26.55.128/2694.26.55.129 to 94.26.55.19094.26.55.19162
9694.26.55.192/2694.26.55.193 to 94.26.55.25494.26.55.25562
9794.26.56.0/2694.26.56.1 to 94.26.56.6294.26.56.6362
9894.26.56.64/2694.26.56.65 to 94.26.56.12694.26.56.12762
9994.26.56.128/2694.26.56.129 to 94.26.56.19094.26.56.19162
10094.26.56.192/2694.26.56.193 to 94.26.56.25494.26.56.25562
10194.26.57.0/2694.26.57.1 to 94.26.57.6294.26.57.6362
10294.26.57.64/2694.26.57.65 to 94.26.57.12694.26.57.12762
10394.26.57.128/2694.26.57.129 to 94.26.57.19094.26.57.19162
10494.26.57.192/2694.26.57.193 to 94.26.57.25494.26.57.25562
10594.26.58.0/2694.26.58.1 to 94.26.58.6294.26.58.6362
10694.26.58.64/2694.26.58.65 to 94.26.58.12694.26.58.12762
10794.26.58.128/2694.26.58.129 to 94.26.58.19094.26.58.19162
10894.26.58.192/2694.26.58.193 to 94.26.58.25494.26.58.25562
10994.26.59.0/2694.26.59.1 to 94.26.59.6294.26.59.6362
11094.26.59.64/2694.26.59.65 to 94.26.59.12694.26.59.12762
11194.26.59.128/2694.26.59.129 to 94.26.59.19094.26.59.19162
11294.26.59.192/2694.26.59.193 to 94.26.59.25494.26.59.25562
11394.26.60.0/2694.26.60.1 to 94.26.60.6294.26.60.6362
11494.26.60.64/2694.26.60.65 to 94.26.60.12694.26.60.12762
11594.26.60.128/2694.26.60.129 to 94.26.60.19094.26.60.19162
11694.26.60.192/2694.26.60.193 to 94.26.60.25494.26.60.25562
11794.26.61.0/2694.26.61.1 to 94.26.61.6294.26.61.6362
11894.26.61.64/2694.26.61.65 to 94.26.61.12694.26.61.12762
11994.26.61.128/2694.26.61.129 to 94.26.61.19094.26.61.19162
12094.26.61.192/2694.26.61.193 to 94.26.61.25494.26.61.25562
12194.26.62.0/2694.26.62.1 to 94.26.62.6294.26.62.6362
12294.26.62.64/2694.26.62.65 to 94.26.62.12694.26.62.12762
12394.26.62.128/2694.26.62.129 to 94.26.62.19094.26.62.19162
12494.26.62.192/2694.26.62.193 to 94.26.62.25494.26.62.25562
12594.26.63.0/2694.26.63.1 to 94.26.63.6294.26.63.6362
12694.26.63.64/2694.26.63.65 to 94.26.63.12694.26.63.12762
12794.26.63.128/2694.26.63.129 to 94.26.63.19094.26.63.19162
12894.26.63.192/2694.26.63.193 to 94.26.63.25494.26.63.25562

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

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.