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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.

Network16.112.0.0/14
Usable hosts262,142
Subnet mask255.252.0.0
Addresses262,144
Network address
16.112.0.0
Broadcast address
16.115.255.255
First usable
16.112.0.1
Last usable
16.115.255.254
Usable hosts
262,142 (262,144 less the network and broadcast addresses)
Subnet mask
255.252.0.0
Wildcard mask
0.3.255.255 (Cisco ACLs, OSPF)
Prefix length
/14
Type
Public public
Old class
A (default /8)
As numbers
Hex 10700000 · Integer 275775488 to 276037631
Reverse DNS zones
112.16.in-addr.arpa
113.16.in-addr.arpa
114.16.in-addr.arpa
115.16.in-addr.arpa
/14 is not on a 8-bit boundary, so it takes 4 /16 zones.
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address00010000.01110000.00000000.0000000016.112.0.0
Subnet mask11111111.11111100.00000000.00000000255.252.0.0
Network00010000.01110000.00000000.0000000016.112.0.0
Broadcast00010000.01110011.11111111.1111111116.115.255.255
Split into smaller subnets/21
/15 (2)/16 (4)/17 (8)/18 (16)/19 (32)/20 (64)/21 (128)/22 (256)/23 (512)/24 (1,024)/25 (2,048)/26 (4,096)

16.112.0.0/14 makes 128 subnets of /21.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
116.112.0.0/2116.112.0.1 to 16.112.7.25416.112.7.2552,046
216.112.8.0/2116.112.8.1 to 16.112.15.25416.112.15.2552,046
316.112.16.0/2116.112.16.1 to 16.112.23.25416.112.23.2552,046
416.112.24.0/2116.112.24.1 to 16.112.31.25416.112.31.2552,046
516.112.32.0/2116.112.32.1 to 16.112.39.25416.112.39.2552,046
616.112.40.0/2116.112.40.1 to 16.112.47.25416.112.47.2552,046
716.112.48.0/2116.112.48.1 to 16.112.55.25416.112.55.2552,046
816.112.56.0/2116.112.56.1 to 16.112.63.25416.112.63.2552,046
916.112.64.0/2116.112.64.1 to 16.112.71.25416.112.71.2552,046
1016.112.72.0/2116.112.72.1 to 16.112.79.25416.112.79.2552,046
1116.112.80.0/2116.112.80.1 to 16.112.87.25416.112.87.2552,046
1216.112.88.0/2116.112.88.1 to 16.112.95.25416.112.95.2552,046
1316.112.96.0/2116.112.96.1 to 16.112.103.25416.112.103.2552,046
1416.112.104.0/2116.112.104.1 to 16.112.111.25416.112.111.2552,046
1516.112.112.0/2116.112.112.1 to 16.112.119.25416.112.119.2552,046
1616.112.120.0/2116.112.120.1 to 16.112.127.25416.112.127.2552,046
1716.112.128.0/2116.112.128.1 to 16.112.135.25416.112.135.2552,046
1816.112.136.0/2116.112.136.1 to 16.112.143.25416.112.143.2552,046
1916.112.144.0/2116.112.144.1 to 16.112.151.25416.112.151.2552,046
2016.112.152.0/2116.112.152.1 to 16.112.159.25416.112.159.2552,046
2116.112.160.0/2116.112.160.1 to 16.112.167.25416.112.167.2552,046
2216.112.168.0/2116.112.168.1 to 16.112.175.25416.112.175.2552,046
2316.112.176.0/2116.112.176.1 to 16.112.183.25416.112.183.2552,046
2416.112.184.0/2116.112.184.1 to 16.112.191.25416.112.191.2552,046
2516.112.192.0/2116.112.192.1 to 16.112.199.25416.112.199.2552,046
2616.112.200.0/2116.112.200.1 to 16.112.207.25416.112.207.2552,046
2716.112.208.0/2116.112.208.1 to 16.112.215.25416.112.215.2552,046
2816.112.216.0/2116.112.216.1 to 16.112.223.25416.112.223.2552,046
2916.112.224.0/2116.112.224.1 to 16.112.231.25416.112.231.2552,046
3016.112.232.0/2116.112.232.1 to 16.112.239.25416.112.239.2552,046
3116.112.240.0/2116.112.240.1 to 16.112.247.25416.112.247.2552,046
3216.112.248.0/2116.112.248.1 to 16.112.255.25416.112.255.2552,046
3316.113.0.0/2116.113.0.1 to 16.113.7.25416.113.7.2552,046
3416.113.8.0/2116.113.8.1 to 16.113.15.25416.113.15.2552,046
3516.113.16.0/2116.113.16.1 to 16.113.23.25416.113.23.2552,046
3616.113.24.0/2116.113.24.1 to 16.113.31.25416.113.31.2552,046
3716.113.32.0/2116.113.32.1 to 16.113.39.25416.113.39.2552,046
3816.113.40.0/2116.113.40.1 to 16.113.47.25416.113.47.2552,046
3916.113.48.0/2116.113.48.1 to 16.113.55.25416.113.55.2552,046
4016.113.56.0/2116.113.56.1 to 16.113.63.25416.113.63.2552,046
4116.113.64.0/2116.113.64.1 to 16.113.71.25416.113.71.2552,046
4216.113.72.0/2116.113.72.1 to 16.113.79.25416.113.79.2552,046
4316.113.80.0/2116.113.80.1 to 16.113.87.25416.113.87.2552,046
4416.113.88.0/2116.113.88.1 to 16.113.95.25416.113.95.2552,046
4516.113.96.0/2116.113.96.1 to 16.113.103.25416.113.103.2552,046
4616.113.104.0/2116.113.104.1 to 16.113.111.25416.113.111.2552,046
4716.113.112.0/2116.113.112.1 to 16.113.119.25416.113.119.2552,046
4816.113.120.0/2116.113.120.1 to 16.113.127.25416.113.127.2552,046
4916.113.128.0/2116.113.128.1 to 16.113.135.25416.113.135.2552,046
5016.113.136.0/2116.113.136.1 to 16.113.143.25416.113.143.2552,046
5116.113.144.0/2116.113.144.1 to 16.113.151.25416.113.151.2552,046
5216.113.152.0/2116.113.152.1 to 16.113.159.25416.113.159.2552,046
5316.113.160.0/2116.113.160.1 to 16.113.167.25416.113.167.2552,046
5416.113.168.0/2116.113.168.1 to 16.113.175.25416.113.175.2552,046
5516.113.176.0/2116.113.176.1 to 16.113.183.25416.113.183.2552,046
5616.113.184.0/2116.113.184.1 to 16.113.191.25416.113.191.2552,046
5716.113.192.0/2116.113.192.1 to 16.113.199.25416.113.199.2552,046
5816.113.200.0/2116.113.200.1 to 16.113.207.25416.113.207.2552,046
5916.113.208.0/2116.113.208.1 to 16.113.215.25416.113.215.2552,046
6016.113.216.0/2116.113.216.1 to 16.113.223.25416.113.223.2552,046
6116.113.224.0/2116.113.224.1 to 16.113.231.25416.113.231.2552,046
6216.113.232.0/2116.113.232.1 to 16.113.239.25416.113.239.2552,046
6316.113.240.0/2116.113.240.1 to 16.113.247.25416.113.247.2552,046
6416.113.248.0/2116.113.248.1 to 16.113.255.25416.113.255.2552,046
6516.114.0.0/2116.114.0.1 to 16.114.7.25416.114.7.2552,046
6616.114.8.0/2116.114.8.1 to 16.114.15.25416.114.15.2552,046
6716.114.16.0/2116.114.16.1 to 16.114.23.25416.114.23.2552,046
6816.114.24.0/2116.114.24.1 to 16.114.31.25416.114.31.2552,046
6916.114.32.0/2116.114.32.1 to 16.114.39.25416.114.39.2552,046
7016.114.40.0/2116.114.40.1 to 16.114.47.25416.114.47.2552,046
7116.114.48.0/2116.114.48.1 to 16.114.55.25416.114.55.2552,046
7216.114.56.0/2116.114.56.1 to 16.114.63.25416.114.63.2552,046
7316.114.64.0/2116.114.64.1 to 16.114.71.25416.114.71.2552,046
7416.114.72.0/2116.114.72.1 to 16.114.79.25416.114.79.2552,046
7516.114.80.0/2116.114.80.1 to 16.114.87.25416.114.87.2552,046
7616.114.88.0/2116.114.88.1 to 16.114.95.25416.114.95.2552,046
7716.114.96.0/2116.114.96.1 to 16.114.103.25416.114.103.2552,046
7816.114.104.0/2116.114.104.1 to 16.114.111.25416.114.111.2552,046
7916.114.112.0/2116.114.112.1 to 16.114.119.25416.114.119.2552,046
8016.114.120.0/2116.114.120.1 to 16.114.127.25416.114.127.2552,046
8116.114.128.0/2116.114.128.1 to 16.114.135.25416.114.135.2552,046
8216.114.136.0/2116.114.136.1 to 16.114.143.25416.114.143.2552,046
8316.114.144.0/2116.114.144.1 to 16.114.151.25416.114.151.2552,046
8416.114.152.0/2116.114.152.1 to 16.114.159.25416.114.159.2552,046
8516.114.160.0/2116.114.160.1 to 16.114.167.25416.114.167.2552,046
8616.114.168.0/2116.114.168.1 to 16.114.175.25416.114.175.2552,046
8716.114.176.0/2116.114.176.1 to 16.114.183.25416.114.183.2552,046
8816.114.184.0/2116.114.184.1 to 16.114.191.25416.114.191.2552,046
8916.114.192.0/2116.114.192.1 to 16.114.199.25416.114.199.2552,046
9016.114.200.0/2116.114.200.1 to 16.114.207.25416.114.207.2552,046
9116.114.208.0/2116.114.208.1 to 16.114.215.25416.114.215.2552,046
9216.114.216.0/2116.114.216.1 to 16.114.223.25416.114.223.2552,046
9316.114.224.0/2116.114.224.1 to 16.114.231.25416.114.231.2552,046
9416.114.232.0/2116.114.232.1 to 16.114.239.25416.114.239.2552,046
9516.114.240.0/2116.114.240.1 to 16.114.247.25416.114.247.2552,046
9616.114.248.0/2116.114.248.1 to 16.114.255.25416.114.255.2552,046
9716.115.0.0/2116.115.0.1 to 16.115.7.25416.115.7.2552,046
9816.115.8.0/2116.115.8.1 to 16.115.15.25416.115.15.2552,046
9916.115.16.0/2116.115.16.1 to 16.115.23.25416.115.23.2552,046
10016.115.24.0/2116.115.24.1 to 16.115.31.25416.115.31.2552,046
10116.115.32.0/2116.115.32.1 to 16.115.39.25416.115.39.2552,046
10216.115.40.0/2116.115.40.1 to 16.115.47.25416.115.47.2552,046
10316.115.48.0/2116.115.48.1 to 16.115.55.25416.115.55.2552,046
10416.115.56.0/2116.115.56.1 to 16.115.63.25416.115.63.2552,046
10516.115.64.0/2116.115.64.1 to 16.115.71.25416.115.71.2552,046
10616.115.72.0/2116.115.72.1 to 16.115.79.25416.115.79.2552,046
10716.115.80.0/2116.115.80.1 to 16.115.87.25416.115.87.2552,046
10816.115.88.0/2116.115.88.1 to 16.115.95.25416.115.95.2552,046
10916.115.96.0/2116.115.96.1 to 16.115.103.25416.115.103.2552,046
11016.115.104.0/2116.115.104.1 to 16.115.111.25416.115.111.2552,046
11116.115.112.0/2116.115.112.1 to 16.115.119.25416.115.119.2552,046
11216.115.120.0/2116.115.120.1 to 16.115.127.25416.115.127.2552,046
11316.115.128.0/2116.115.128.1 to 16.115.135.25416.115.135.2552,046
11416.115.136.0/2116.115.136.1 to 16.115.143.25416.115.143.2552,046
11516.115.144.0/2116.115.144.1 to 16.115.151.25416.115.151.2552,046
11616.115.152.0/2116.115.152.1 to 16.115.159.25416.115.159.2552,046
11716.115.160.0/2116.115.160.1 to 16.115.167.25416.115.167.2552,046
11816.115.168.0/2116.115.168.1 to 16.115.175.25416.115.175.2552,046
11916.115.176.0/2116.115.176.1 to 16.115.183.25416.115.183.2552,046
12016.115.184.0/2116.115.184.1 to 16.115.191.25416.115.191.2552,046
12116.115.192.0/2116.115.192.1 to 16.115.199.25416.115.199.2552,046
12216.115.200.0/2116.115.200.1 to 16.115.207.25416.115.207.2552,046
12316.115.208.0/2116.115.208.1 to 16.115.215.25416.115.215.2552,046
12416.115.216.0/2116.115.216.1 to 16.115.223.25416.115.223.2552,046
12516.115.224.0/2116.115.224.1 to 16.115.231.25416.115.231.2552,046
12616.115.232.0/2116.115.232.1 to 16.115.239.25416.115.239.2552,046
12716.115.240.0/2116.115.240.1 to 16.115.247.25416.115.247.2552,046
12816.115.248.0/2116.115.248.1 to 16.115.255.25416.115.255.2552,046

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.