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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.

Network94.0.0.0/7
Usable hosts33,554,430
Subnet mask254.0.0.0
Addresses33,554,432
Network address
94.0.0.0
Broadcast address
95.255.255.255
First usable
94.0.0.1
Last usable
95.255.255.254
Usable hosts
33,554,430 (33,554,432 less the network and broadcast addresses)
Subnet mask
254.0.0.0
Wildcard mask
1.255.255.255 (Cisco ACLs, OSPF)
Prefix length
/7
Type
Public public
Old class
A (default /8)
As numbers
Hex 5E000000 · Integer 1577058304 to 1610612735
Reverse DNS zones
94.in-addr.arpa
95.in-addr.arpa
/7 is not on a 8-bit boundary, so it takes 2 /8 zones.
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address01011110.00000000.00000000.0000000094.0.0.0
Subnet mask11111110.00000000.00000000.00000000254.0.0.0
Network01011110.00000000.00000000.0000000094.0.0.0
Broadcast01011111.11111111.11111111.1111111195.255.255.255
Split into smaller subnets/14
/8 (2)/9 (4)/10 (8)/11 (16)/12 (32)/13 (64)/14 (128)/15 (256)/16 (512)/17 (1,024)/18 (2,048)/19 (4,096)

94.0.0.0/7 makes 128 subnets of /14.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
194.0.0.0/1494.0.0.1 to 94.3.255.25494.3.255.255262,142
294.4.0.0/1494.4.0.1 to 94.7.255.25494.7.255.255262,142
394.8.0.0/1494.8.0.1 to 94.11.255.25494.11.255.255262,142
494.12.0.0/1494.12.0.1 to 94.15.255.25494.15.255.255262,142
594.16.0.0/1494.16.0.1 to 94.19.255.25494.19.255.255262,142
694.20.0.0/1494.20.0.1 to 94.23.255.25494.23.255.255262,142
794.24.0.0/1494.24.0.1 to 94.27.255.25494.27.255.255262,142
894.28.0.0/1494.28.0.1 to 94.31.255.25494.31.255.255262,142
994.32.0.0/1494.32.0.1 to 94.35.255.25494.35.255.255262,142
1094.36.0.0/1494.36.0.1 to 94.39.255.25494.39.255.255262,142
1194.40.0.0/1494.40.0.1 to 94.43.255.25494.43.255.255262,142
1294.44.0.0/1494.44.0.1 to 94.47.255.25494.47.255.255262,142
1394.48.0.0/1494.48.0.1 to 94.51.255.25494.51.255.255262,142
1494.52.0.0/1494.52.0.1 to 94.55.255.25494.55.255.255262,142
1594.56.0.0/1494.56.0.1 to 94.59.255.25494.59.255.255262,142
1694.60.0.0/1494.60.0.1 to 94.63.255.25494.63.255.255262,142
1794.64.0.0/1494.64.0.1 to 94.67.255.25494.67.255.255262,142
1894.68.0.0/1494.68.0.1 to 94.71.255.25494.71.255.255262,142
1994.72.0.0/1494.72.0.1 to 94.75.255.25494.75.255.255262,142
2094.76.0.0/1494.76.0.1 to 94.79.255.25494.79.255.255262,142
2194.80.0.0/1494.80.0.1 to 94.83.255.25494.83.255.255262,142
2294.84.0.0/1494.84.0.1 to 94.87.255.25494.87.255.255262,142
2394.88.0.0/1494.88.0.1 to 94.91.255.25494.91.255.255262,142
2494.92.0.0/1494.92.0.1 to 94.95.255.25494.95.255.255262,142
2594.96.0.0/1494.96.0.1 to 94.99.255.25494.99.255.255262,142
2694.100.0.0/1494.100.0.1 to 94.103.255.25494.103.255.255262,142
2794.104.0.0/1494.104.0.1 to 94.107.255.25494.107.255.255262,142
2894.108.0.0/1494.108.0.1 to 94.111.255.25494.111.255.255262,142
2994.112.0.0/1494.112.0.1 to 94.115.255.25494.115.255.255262,142
3094.116.0.0/1494.116.0.1 to 94.119.255.25494.119.255.255262,142
3194.120.0.0/1494.120.0.1 to 94.123.255.25494.123.255.255262,142
3294.124.0.0/1494.124.0.1 to 94.127.255.25494.127.255.255262,142
3394.128.0.0/1494.128.0.1 to 94.131.255.25494.131.255.255262,142
3494.132.0.0/1494.132.0.1 to 94.135.255.25494.135.255.255262,142
3594.136.0.0/1494.136.0.1 to 94.139.255.25494.139.255.255262,142
3694.140.0.0/1494.140.0.1 to 94.143.255.25494.143.255.255262,142
3794.144.0.0/1494.144.0.1 to 94.147.255.25494.147.255.255262,142
3894.148.0.0/1494.148.0.1 to 94.151.255.25494.151.255.255262,142
3994.152.0.0/1494.152.0.1 to 94.155.255.25494.155.255.255262,142
4094.156.0.0/1494.156.0.1 to 94.159.255.25494.159.255.255262,142
4194.160.0.0/1494.160.0.1 to 94.163.255.25494.163.255.255262,142
4294.164.0.0/1494.164.0.1 to 94.167.255.25494.167.255.255262,142
4394.168.0.0/1494.168.0.1 to 94.171.255.25494.171.255.255262,142
4494.172.0.0/1494.172.0.1 to 94.175.255.25494.175.255.255262,142
4594.176.0.0/1494.176.0.1 to 94.179.255.25494.179.255.255262,142
4694.180.0.0/1494.180.0.1 to 94.183.255.25494.183.255.255262,142
4794.184.0.0/1494.184.0.1 to 94.187.255.25494.187.255.255262,142
4894.188.0.0/1494.188.0.1 to 94.191.255.25494.191.255.255262,142
4994.192.0.0/1494.192.0.1 to 94.195.255.25494.195.255.255262,142
5094.196.0.0/1494.196.0.1 to 94.199.255.25494.199.255.255262,142
5194.200.0.0/1494.200.0.1 to 94.203.255.25494.203.255.255262,142
5294.204.0.0/1494.204.0.1 to 94.207.255.25494.207.255.255262,142
5394.208.0.0/1494.208.0.1 to 94.211.255.25494.211.255.255262,142
5494.212.0.0/1494.212.0.1 to 94.215.255.25494.215.255.255262,142
5594.216.0.0/1494.216.0.1 to 94.219.255.25494.219.255.255262,142
5694.220.0.0/1494.220.0.1 to 94.223.255.25494.223.255.255262,142
5794.224.0.0/1494.224.0.1 to 94.227.255.25494.227.255.255262,142
5894.228.0.0/1494.228.0.1 to 94.231.255.25494.231.255.255262,142
5994.232.0.0/1494.232.0.1 to 94.235.255.25494.235.255.255262,142
6094.236.0.0/1494.236.0.1 to 94.239.255.25494.239.255.255262,142
6194.240.0.0/1494.240.0.1 to 94.243.255.25494.243.255.255262,142
6294.244.0.0/1494.244.0.1 to 94.247.255.25494.247.255.255262,142
6394.248.0.0/1494.248.0.1 to 94.251.255.25494.251.255.255262,142
6494.252.0.0/1494.252.0.1 to 94.255.255.25494.255.255.255262,142
6595.0.0.0/1495.0.0.1 to 95.3.255.25495.3.255.255262,142
6695.4.0.0/1495.4.0.1 to 95.7.255.25495.7.255.255262,142
6795.8.0.0/1495.8.0.1 to 95.11.255.25495.11.255.255262,142
6895.12.0.0/1495.12.0.1 to 95.15.255.25495.15.255.255262,142
6995.16.0.0/1495.16.0.1 to 95.19.255.25495.19.255.255262,142
7095.20.0.0/1495.20.0.1 to 95.23.255.25495.23.255.255262,142
7195.24.0.0/1495.24.0.1 to 95.27.255.25495.27.255.255262,142
7295.28.0.0/1495.28.0.1 to 95.31.255.25495.31.255.255262,142
7395.32.0.0/1495.32.0.1 to 95.35.255.25495.35.255.255262,142
7495.36.0.0/1495.36.0.1 to 95.39.255.25495.39.255.255262,142
7595.40.0.0/1495.40.0.1 to 95.43.255.25495.43.255.255262,142
7695.44.0.0/1495.44.0.1 to 95.47.255.25495.47.255.255262,142
7795.48.0.0/1495.48.0.1 to 95.51.255.25495.51.255.255262,142
7895.52.0.0/1495.52.0.1 to 95.55.255.25495.55.255.255262,142
7995.56.0.0/1495.56.0.1 to 95.59.255.25495.59.255.255262,142
8095.60.0.0/1495.60.0.1 to 95.63.255.25495.63.255.255262,142
8195.64.0.0/1495.64.0.1 to 95.67.255.25495.67.255.255262,142
8295.68.0.0/1495.68.0.1 to 95.71.255.25495.71.255.255262,142
8395.72.0.0/1495.72.0.1 to 95.75.255.25495.75.255.255262,142
8495.76.0.0/1495.76.0.1 to 95.79.255.25495.79.255.255262,142
8595.80.0.0/1495.80.0.1 to 95.83.255.25495.83.255.255262,142
8695.84.0.0/1495.84.0.1 to 95.87.255.25495.87.255.255262,142
8795.88.0.0/1495.88.0.1 to 95.91.255.25495.91.255.255262,142
8895.92.0.0/1495.92.0.1 to 95.95.255.25495.95.255.255262,142
8995.96.0.0/1495.96.0.1 to 95.99.255.25495.99.255.255262,142
9095.100.0.0/1495.100.0.1 to 95.103.255.25495.103.255.255262,142
9195.104.0.0/1495.104.0.1 to 95.107.255.25495.107.255.255262,142
9295.108.0.0/1495.108.0.1 to 95.111.255.25495.111.255.255262,142
9395.112.0.0/1495.112.0.1 to 95.115.255.25495.115.255.255262,142
9495.116.0.0/1495.116.0.1 to 95.119.255.25495.119.255.255262,142
9595.120.0.0/1495.120.0.1 to 95.123.255.25495.123.255.255262,142
9695.124.0.0/1495.124.0.1 to 95.127.255.25495.127.255.255262,142
9795.128.0.0/1495.128.0.1 to 95.131.255.25495.131.255.255262,142
9895.132.0.0/1495.132.0.1 to 95.135.255.25495.135.255.255262,142
9995.136.0.0/1495.136.0.1 to 95.139.255.25495.139.255.255262,142
10095.140.0.0/1495.140.0.1 to 95.143.255.25495.143.255.255262,142
10195.144.0.0/1495.144.0.1 to 95.147.255.25495.147.255.255262,142
10295.148.0.0/1495.148.0.1 to 95.151.255.25495.151.255.255262,142
10395.152.0.0/1495.152.0.1 to 95.155.255.25495.155.255.255262,142
10495.156.0.0/1495.156.0.1 to 95.159.255.25495.159.255.255262,142
10595.160.0.0/1495.160.0.1 to 95.163.255.25495.163.255.255262,142
10695.164.0.0/1495.164.0.1 to 95.167.255.25495.167.255.255262,142
10795.168.0.0/1495.168.0.1 to 95.171.255.25495.171.255.255262,142
10895.172.0.0/1495.172.0.1 to 95.175.255.25495.175.255.255262,142
10995.176.0.0/1495.176.0.1 to 95.179.255.25495.179.255.255262,142
11095.180.0.0/1495.180.0.1 to 95.183.255.25495.183.255.255262,142
11195.184.0.0/1495.184.0.1 to 95.187.255.25495.187.255.255262,142
11295.188.0.0/1495.188.0.1 to 95.191.255.25495.191.255.255262,142
11395.192.0.0/1495.192.0.1 to 95.195.255.25495.195.255.255262,142
11495.196.0.0/1495.196.0.1 to 95.199.255.25495.199.255.255262,142
11595.200.0.0/1495.200.0.1 to 95.203.255.25495.203.255.255262,142
11695.204.0.0/1495.204.0.1 to 95.207.255.25495.207.255.255262,142
11795.208.0.0/1495.208.0.1 to 95.211.255.25495.211.255.255262,142
11895.212.0.0/1495.212.0.1 to 95.215.255.25495.215.255.255262,142
11995.216.0.0/1495.216.0.1 to 95.219.255.25495.219.255.255262,142
12095.220.0.0/1495.220.0.1 to 95.223.255.25495.223.255.255262,142
12195.224.0.0/1495.224.0.1 to 95.227.255.25495.227.255.255262,142
12295.228.0.0/1495.228.0.1 to 95.231.255.25495.231.255.255262,142
12395.232.0.0/1495.232.0.1 to 95.235.255.25495.235.255.255262,142
12495.236.0.0/1495.236.0.1 to 95.239.255.25495.239.255.255262,142
12595.240.0.0/1495.240.0.1 to 95.243.255.25495.243.255.255262,142
12695.244.0.0/1495.244.0.1 to 95.247.255.25495.247.255.255262,142
12795.248.0.0/1495.248.0.1 to 95.251.255.25495.251.255.255262,142
12895.252.0.0/1495.252.0.1 to 95.255.255.25495.255.255.255262,142

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.