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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.

Network94.0.0.0/11
Usable hosts2,097,150
Subnet mask255.224.0.0
Addresses2,097,152
Network address
94.0.0.0
Broadcast address
94.31.255.255
First usable
94.0.0.1
Last usable
94.31.255.254
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 5E000000 · Integer 1577058304 to 1579155455
Reverse DNS zones
0.94.in-addr.arpa
1.94.in-addr.arpa
2.94.in-addr.arpa
3.94.in-addr.arpa
4.94.in-addr.arpa
5.94.in-addr.arpa
6.94.in-addr.arpa
7.94.in-addr.arpa
8.94.in-addr.arpa
9.94.in-addr.arpa
10.94.in-addr.arpa
11.94.in-addr.arpa
12.94.in-addr.arpa
13.94.in-addr.arpa
14.94.in-addr.arpa
15.94.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
Address01011110.00000000.00000000.0000000094.0.0.0
Subnet mask11111111.11100000.00000000.00000000255.224.0.0
Network01011110.00000000.00000000.0000000094.0.0.0
Broadcast01011110.00011111.11111111.1111111194.31.255.255
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)

94.0.0.0/11 makes 128 subnets of /18.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
194.0.0.0/1894.0.0.1 to 94.0.63.25494.0.63.25516,382
294.0.64.0/1894.0.64.1 to 94.0.127.25494.0.127.25516,382
394.0.128.0/1894.0.128.1 to 94.0.191.25494.0.191.25516,382
494.0.192.0/1894.0.192.1 to 94.0.255.25494.0.255.25516,382
594.1.0.0/1894.1.0.1 to 94.1.63.25494.1.63.25516,382
694.1.64.0/1894.1.64.1 to 94.1.127.25494.1.127.25516,382
794.1.128.0/1894.1.128.1 to 94.1.191.25494.1.191.25516,382
894.1.192.0/1894.1.192.1 to 94.1.255.25494.1.255.25516,382
994.2.0.0/1894.2.0.1 to 94.2.63.25494.2.63.25516,382
1094.2.64.0/1894.2.64.1 to 94.2.127.25494.2.127.25516,382
1194.2.128.0/1894.2.128.1 to 94.2.191.25494.2.191.25516,382
1294.2.192.0/1894.2.192.1 to 94.2.255.25494.2.255.25516,382
1394.3.0.0/1894.3.0.1 to 94.3.63.25494.3.63.25516,382
1494.3.64.0/1894.3.64.1 to 94.3.127.25494.3.127.25516,382
1594.3.128.0/1894.3.128.1 to 94.3.191.25494.3.191.25516,382
1694.3.192.0/1894.3.192.1 to 94.3.255.25494.3.255.25516,382
1794.4.0.0/1894.4.0.1 to 94.4.63.25494.4.63.25516,382
1894.4.64.0/1894.4.64.1 to 94.4.127.25494.4.127.25516,382
1994.4.128.0/1894.4.128.1 to 94.4.191.25494.4.191.25516,382
2094.4.192.0/1894.4.192.1 to 94.4.255.25494.4.255.25516,382
2194.5.0.0/1894.5.0.1 to 94.5.63.25494.5.63.25516,382
2294.5.64.0/1894.5.64.1 to 94.5.127.25494.5.127.25516,382
2394.5.128.0/1894.5.128.1 to 94.5.191.25494.5.191.25516,382
2494.5.192.0/1894.5.192.1 to 94.5.255.25494.5.255.25516,382
2594.6.0.0/1894.6.0.1 to 94.6.63.25494.6.63.25516,382
2694.6.64.0/1894.6.64.1 to 94.6.127.25494.6.127.25516,382
2794.6.128.0/1894.6.128.1 to 94.6.191.25494.6.191.25516,382
2894.6.192.0/1894.6.192.1 to 94.6.255.25494.6.255.25516,382
2994.7.0.0/1894.7.0.1 to 94.7.63.25494.7.63.25516,382
3094.7.64.0/1894.7.64.1 to 94.7.127.25494.7.127.25516,382
3194.7.128.0/1894.7.128.1 to 94.7.191.25494.7.191.25516,382
3294.7.192.0/1894.7.192.1 to 94.7.255.25494.7.255.25516,382
3394.8.0.0/1894.8.0.1 to 94.8.63.25494.8.63.25516,382
3494.8.64.0/1894.8.64.1 to 94.8.127.25494.8.127.25516,382
3594.8.128.0/1894.8.128.1 to 94.8.191.25494.8.191.25516,382
3694.8.192.0/1894.8.192.1 to 94.8.255.25494.8.255.25516,382
3794.9.0.0/1894.9.0.1 to 94.9.63.25494.9.63.25516,382
3894.9.64.0/1894.9.64.1 to 94.9.127.25494.9.127.25516,382
3994.9.128.0/1894.9.128.1 to 94.9.191.25494.9.191.25516,382
4094.9.192.0/1894.9.192.1 to 94.9.255.25494.9.255.25516,382
4194.10.0.0/1894.10.0.1 to 94.10.63.25494.10.63.25516,382
4294.10.64.0/1894.10.64.1 to 94.10.127.25494.10.127.25516,382
4394.10.128.0/1894.10.128.1 to 94.10.191.25494.10.191.25516,382
4494.10.192.0/1894.10.192.1 to 94.10.255.25494.10.255.25516,382
4594.11.0.0/1894.11.0.1 to 94.11.63.25494.11.63.25516,382
4694.11.64.0/1894.11.64.1 to 94.11.127.25494.11.127.25516,382
4794.11.128.0/1894.11.128.1 to 94.11.191.25494.11.191.25516,382
4894.11.192.0/1894.11.192.1 to 94.11.255.25494.11.255.25516,382
4994.12.0.0/1894.12.0.1 to 94.12.63.25494.12.63.25516,382
5094.12.64.0/1894.12.64.1 to 94.12.127.25494.12.127.25516,382
5194.12.128.0/1894.12.128.1 to 94.12.191.25494.12.191.25516,382
5294.12.192.0/1894.12.192.1 to 94.12.255.25494.12.255.25516,382
5394.13.0.0/1894.13.0.1 to 94.13.63.25494.13.63.25516,382
5494.13.64.0/1894.13.64.1 to 94.13.127.25494.13.127.25516,382
5594.13.128.0/1894.13.128.1 to 94.13.191.25494.13.191.25516,382
5694.13.192.0/1894.13.192.1 to 94.13.255.25494.13.255.25516,382
5794.14.0.0/1894.14.0.1 to 94.14.63.25494.14.63.25516,382
5894.14.64.0/1894.14.64.1 to 94.14.127.25494.14.127.25516,382
5994.14.128.0/1894.14.128.1 to 94.14.191.25494.14.191.25516,382
6094.14.192.0/1894.14.192.1 to 94.14.255.25494.14.255.25516,382
6194.15.0.0/1894.15.0.1 to 94.15.63.25494.15.63.25516,382
6294.15.64.0/1894.15.64.1 to 94.15.127.25494.15.127.25516,382
6394.15.128.0/1894.15.128.1 to 94.15.191.25494.15.191.25516,382
6494.15.192.0/1894.15.192.1 to 94.15.255.25494.15.255.25516,382
6594.16.0.0/1894.16.0.1 to 94.16.63.25494.16.63.25516,382
6694.16.64.0/1894.16.64.1 to 94.16.127.25494.16.127.25516,382
6794.16.128.0/1894.16.128.1 to 94.16.191.25494.16.191.25516,382
6894.16.192.0/1894.16.192.1 to 94.16.255.25494.16.255.25516,382
6994.17.0.0/1894.17.0.1 to 94.17.63.25494.17.63.25516,382
7094.17.64.0/1894.17.64.1 to 94.17.127.25494.17.127.25516,382
7194.17.128.0/1894.17.128.1 to 94.17.191.25494.17.191.25516,382
7294.17.192.0/1894.17.192.1 to 94.17.255.25494.17.255.25516,382
7394.18.0.0/1894.18.0.1 to 94.18.63.25494.18.63.25516,382
7494.18.64.0/1894.18.64.1 to 94.18.127.25494.18.127.25516,382
7594.18.128.0/1894.18.128.1 to 94.18.191.25494.18.191.25516,382
7694.18.192.0/1894.18.192.1 to 94.18.255.25494.18.255.25516,382
7794.19.0.0/1894.19.0.1 to 94.19.63.25494.19.63.25516,382
7894.19.64.0/1894.19.64.1 to 94.19.127.25494.19.127.25516,382
7994.19.128.0/1894.19.128.1 to 94.19.191.25494.19.191.25516,382
8094.19.192.0/1894.19.192.1 to 94.19.255.25494.19.255.25516,382
8194.20.0.0/1894.20.0.1 to 94.20.63.25494.20.63.25516,382
8294.20.64.0/1894.20.64.1 to 94.20.127.25494.20.127.25516,382
8394.20.128.0/1894.20.128.1 to 94.20.191.25494.20.191.25516,382
8494.20.192.0/1894.20.192.1 to 94.20.255.25494.20.255.25516,382
8594.21.0.0/1894.21.0.1 to 94.21.63.25494.21.63.25516,382
8694.21.64.0/1894.21.64.1 to 94.21.127.25494.21.127.25516,382
8794.21.128.0/1894.21.128.1 to 94.21.191.25494.21.191.25516,382
8894.21.192.0/1894.21.192.1 to 94.21.255.25494.21.255.25516,382
8994.22.0.0/1894.22.0.1 to 94.22.63.25494.22.63.25516,382
9094.22.64.0/1894.22.64.1 to 94.22.127.25494.22.127.25516,382
9194.22.128.0/1894.22.128.1 to 94.22.191.25494.22.191.25516,382
9294.22.192.0/1894.22.192.1 to 94.22.255.25494.22.255.25516,382
9394.23.0.0/1894.23.0.1 to 94.23.63.25494.23.63.25516,382
9494.23.64.0/1894.23.64.1 to 94.23.127.25494.23.127.25516,382
9594.23.128.0/1894.23.128.1 to 94.23.191.25494.23.191.25516,382
9694.23.192.0/1894.23.192.1 to 94.23.255.25494.23.255.25516,382
9794.24.0.0/1894.24.0.1 to 94.24.63.25494.24.63.25516,382
9894.24.64.0/1894.24.64.1 to 94.24.127.25494.24.127.25516,382
9994.24.128.0/1894.24.128.1 to 94.24.191.25494.24.191.25516,382
10094.24.192.0/1894.24.192.1 to 94.24.255.25494.24.255.25516,382
10194.25.0.0/1894.25.0.1 to 94.25.63.25494.25.63.25516,382
10294.25.64.0/1894.25.64.1 to 94.25.127.25494.25.127.25516,382
10394.25.128.0/1894.25.128.1 to 94.25.191.25494.25.191.25516,382
10494.25.192.0/1894.25.192.1 to 94.25.255.25494.25.255.25516,382
10594.26.0.0/1894.26.0.1 to 94.26.63.25494.26.63.25516,382
10694.26.64.0/1894.26.64.1 to 94.26.127.25494.26.127.25516,382
10794.26.128.0/1894.26.128.1 to 94.26.191.25494.26.191.25516,382
10894.26.192.0/1894.26.192.1 to 94.26.255.25494.26.255.25516,382
10994.27.0.0/1894.27.0.1 to 94.27.63.25494.27.63.25516,382
11094.27.64.0/1894.27.64.1 to 94.27.127.25494.27.127.25516,382
11194.27.128.0/1894.27.128.1 to 94.27.191.25494.27.191.25516,382
11294.27.192.0/1894.27.192.1 to 94.27.255.25494.27.255.25516,382
11394.28.0.0/1894.28.0.1 to 94.28.63.25494.28.63.25516,382
11494.28.64.0/1894.28.64.1 to 94.28.127.25494.28.127.25516,382
11594.28.128.0/1894.28.128.1 to 94.28.191.25494.28.191.25516,382
11694.28.192.0/1894.28.192.1 to 94.28.255.25494.28.255.25516,382
11794.29.0.0/1894.29.0.1 to 94.29.63.25494.29.63.25516,382
11894.29.64.0/1894.29.64.1 to 94.29.127.25494.29.127.25516,382
11994.29.128.0/1894.29.128.1 to 94.29.191.25494.29.191.25516,382
12094.29.192.0/1894.29.192.1 to 94.29.255.25494.29.255.25516,382
12194.30.0.0/1894.30.0.1 to 94.30.63.25494.30.63.25516,382
12294.30.64.0/1894.30.64.1 to 94.30.127.25494.30.127.25516,382
12394.30.128.0/1894.30.128.1 to 94.30.191.25494.30.191.25516,382
12494.30.192.0/1894.30.192.1 to 94.30.255.25494.30.255.25516,382
12594.31.0.0/1894.31.0.1 to 94.31.63.25494.31.63.25516,382
12694.31.64.0/1894.31.64.1 to 94.31.127.25494.31.127.25516,382
12794.31.128.0/1894.31.128.1 to 94.31.191.25494.31.191.25516,382
12894.31.192.0/1894.31.192.1 to 94.31.255.25494.31.255.25516,382

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.