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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.

Network52.80.0.0/14
Usable hosts262,142
Subnet mask255.252.0.0
Addresses262,144
Network address
52.80.0.0
Broadcast address
52.83.255.255
First usable
52.80.0.1
Last usable
52.83.255.254
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 34500000 · Integer 877658112 to 877920255
Reverse DNS zones
80.52.in-addr.arpa
81.52.in-addr.arpa
82.52.in-addr.arpa
83.52.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
Address00110100.01010000.00000000.0000000052.80.0.0
Subnet mask11111111.11111100.00000000.00000000255.252.0.0
Network00110100.01010000.00000000.0000000052.80.0.0
Broadcast00110100.01010011.11111111.1111111152.83.255.255
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)

52.80.0.0/14 makes 128 subnets of /21.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
152.80.0.0/2152.80.0.1 to 52.80.7.25452.80.7.2552,046
252.80.8.0/2152.80.8.1 to 52.80.15.25452.80.15.2552,046
352.80.16.0/2152.80.16.1 to 52.80.23.25452.80.23.2552,046
452.80.24.0/2152.80.24.1 to 52.80.31.25452.80.31.2552,046
552.80.32.0/2152.80.32.1 to 52.80.39.25452.80.39.2552,046
652.80.40.0/2152.80.40.1 to 52.80.47.25452.80.47.2552,046
752.80.48.0/2152.80.48.1 to 52.80.55.25452.80.55.2552,046
852.80.56.0/2152.80.56.1 to 52.80.63.25452.80.63.2552,046
952.80.64.0/2152.80.64.1 to 52.80.71.25452.80.71.2552,046
1052.80.72.0/2152.80.72.1 to 52.80.79.25452.80.79.2552,046
1152.80.80.0/2152.80.80.1 to 52.80.87.25452.80.87.2552,046
1252.80.88.0/2152.80.88.1 to 52.80.95.25452.80.95.2552,046
1352.80.96.0/2152.80.96.1 to 52.80.103.25452.80.103.2552,046
1452.80.104.0/2152.80.104.1 to 52.80.111.25452.80.111.2552,046
1552.80.112.0/2152.80.112.1 to 52.80.119.25452.80.119.2552,046
1652.80.120.0/2152.80.120.1 to 52.80.127.25452.80.127.2552,046
1752.80.128.0/2152.80.128.1 to 52.80.135.25452.80.135.2552,046
1852.80.136.0/2152.80.136.1 to 52.80.143.25452.80.143.2552,046
1952.80.144.0/2152.80.144.1 to 52.80.151.25452.80.151.2552,046
2052.80.152.0/2152.80.152.1 to 52.80.159.25452.80.159.2552,046
2152.80.160.0/2152.80.160.1 to 52.80.167.25452.80.167.2552,046
2252.80.168.0/2152.80.168.1 to 52.80.175.25452.80.175.2552,046
2352.80.176.0/2152.80.176.1 to 52.80.183.25452.80.183.2552,046
2452.80.184.0/2152.80.184.1 to 52.80.191.25452.80.191.2552,046
2552.80.192.0/2152.80.192.1 to 52.80.199.25452.80.199.2552,046
2652.80.200.0/2152.80.200.1 to 52.80.207.25452.80.207.2552,046
2752.80.208.0/2152.80.208.1 to 52.80.215.25452.80.215.2552,046
2852.80.216.0/2152.80.216.1 to 52.80.223.25452.80.223.2552,046
2952.80.224.0/2152.80.224.1 to 52.80.231.25452.80.231.2552,046
3052.80.232.0/2152.80.232.1 to 52.80.239.25452.80.239.2552,046
3152.80.240.0/2152.80.240.1 to 52.80.247.25452.80.247.2552,046
3252.80.248.0/2152.80.248.1 to 52.80.255.25452.80.255.2552,046
3352.81.0.0/2152.81.0.1 to 52.81.7.25452.81.7.2552,046
3452.81.8.0/2152.81.8.1 to 52.81.15.25452.81.15.2552,046
3552.81.16.0/2152.81.16.1 to 52.81.23.25452.81.23.2552,046
3652.81.24.0/2152.81.24.1 to 52.81.31.25452.81.31.2552,046
3752.81.32.0/2152.81.32.1 to 52.81.39.25452.81.39.2552,046
3852.81.40.0/2152.81.40.1 to 52.81.47.25452.81.47.2552,046
3952.81.48.0/2152.81.48.1 to 52.81.55.25452.81.55.2552,046
4052.81.56.0/2152.81.56.1 to 52.81.63.25452.81.63.2552,046
4152.81.64.0/2152.81.64.1 to 52.81.71.25452.81.71.2552,046
4252.81.72.0/2152.81.72.1 to 52.81.79.25452.81.79.2552,046
4352.81.80.0/2152.81.80.1 to 52.81.87.25452.81.87.2552,046
4452.81.88.0/2152.81.88.1 to 52.81.95.25452.81.95.2552,046
4552.81.96.0/2152.81.96.1 to 52.81.103.25452.81.103.2552,046
4652.81.104.0/2152.81.104.1 to 52.81.111.25452.81.111.2552,046
4752.81.112.0/2152.81.112.1 to 52.81.119.25452.81.119.2552,046
4852.81.120.0/2152.81.120.1 to 52.81.127.25452.81.127.2552,046
4952.81.128.0/2152.81.128.1 to 52.81.135.25452.81.135.2552,046
5052.81.136.0/2152.81.136.1 to 52.81.143.25452.81.143.2552,046
5152.81.144.0/2152.81.144.1 to 52.81.151.25452.81.151.2552,046
5252.81.152.0/2152.81.152.1 to 52.81.159.25452.81.159.2552,046
5352.81.160.0/2152.81.160.1 to 52.81.167.25452.81.167.2552,046
5452.81.168.0/2152.81.168.1 to 52.81.175.25452.81.175.2552,046
5552.81.176.0/2152.81.176.1 to 52.81.183.25452.81.183.2552,046
5652.81.184.0/2152.81.184.1 to 52.81.191.25452.81.191.2552,046
5752.81.192.0/2152.81.192.1 to 52.81.199.25452.81.199.2552,046
5852.81.200.0/2152.81.200.1 to 52.81.207.25452.81.207.2552,046
5952.81.208.0/2152.81.208.1 to 52.81.215.25452.81.215.2552,046
6052.81.216.0/2152.81.216.1 to 52.81.223.25452.81.223.2552,046
6152.81.224.0/2152.81.224.1 to 52.81.231.25452.81.231.2552,046
6252.81.232.0/2152.81.232.1 to 52.81.239.25452.81.239.2552,046
6352.81.240.0/2152.81.240.1 to 52.81.247.25452.81.247.2552,046
6452.81.248.0/2152.81.248.1 to 52.81.255.25452.81.255.2552,046
6552.82.0.0/2152.82.0.1 to 52.82.7.25452.82.7.2552,046
6652.82.8.0/2152.82.8.1 to 52.82.15.25452.82.15.2552,046
6752.82.16.0/2152.82.16.1 to 52.82.23.25452.82.23.2552,046
6852.82.24.0/2152.82.24.1 to 52.82.31.25452.82.31.2552,046
6952.82.32.0/2152.82.32.1 to 52.82.39.25452.82.39.2552,046
7052.82.40.0/2152.82.40.1 to 52.82.47.25452.82.47.2552,046
7152.82.48.0/2152.82.48.1 to 52.82.55.25452.82.55.2552,046
7252.82.56.0/2152.82.56.1 to 52.82.63.25452.82.63.2552,046
7352.82.64.0/2152.82.64.1 to 52.82.71.25452.82.71.2552,046
7452.82.72.0/2152.82.72.1 to 52.82.79.25452.82.79.2552,046
7552.82.80.0/2152.82.80.1 to 52.82.87.25452.82.87.2552,046
7652.82.88.0/2152.82.88.1 to 52.82.95.25452.82.95.2552,046
7752.82.96.0/2152.82.96.1 to 52.82.103.25452.82.103.2552,046
7852.82.104.0/2152.82.104.1 to 52.82.111.25452.82.111.2552,046
7952.82.112.0/2152.82.112.1 to 52.82.119.25452.82.119.2552,046
8052.82.120.0/2152.82.120.1 to 52.82.127.25452.82.127.2552,046
8152.82.128.0/2152.82.128.1 to 52.82.135.25452.82.135.2552,046
8252.82.136.0/2152.82.136.1 to 52.82.143.25452.82.143.2552,046
8352.82.144.0/2152.82.144.1 to 52.82.151.25452.82.151.2552,046
8452.82.152.0/2152.82.152.1 to 52.82.159.25452.82.159.2552,046
8552.82.160.0/2152.82.160.1 to 52.82.167.25452.82.167.2552,046
8652.82.168.0/2152.82.168.1 to 52.82.175.25452.82.175.2552,046
8752.82.176.0/2152.82.176.1 to 52.82.183.25452.82.183.2552,046
8852.82.184.0/2152.82.184.1 to 52.82.191.25452.82.191.2552,046
8952.82.192.0/2152.82.192.1 to 52.82.199.25452.82.199.2552,046
9052.82.200.0/2152.82.200.1 to 52.82.207.25452.82.207.2552,046
9152.82.208.0/2152.82.208.1 to 52.82.215.25452.82.215.2552,046
9252.82.216.0/2152.82.216.1 to 52.82.223.25452.82.223.2552,046
9352.82.224.0/2152.82.224.1 to 52.82.231.25452.82.231.2552,046
9452.82.232.0/2152.82.232.1 to 52.82.239.25452.82.239.2552,046
9552.82.240.0/2152.82.240.1 to 52.82.247.25452.82.247.2552,046
9652.82.248.0/2152.82.248.1 to 52.82.255.25452.82.255.2552,046
9752.83.0.0/2152.83.0.1 to 52.83.7.25452.83.7.2552,046
9852.83.8.0/2152.83.8.1 to 52.83.15.25452.83.15.2552,046
9952.83.16.0/2152.83.16.1 to 52.83.23.25452.83.23.2552,046
10052.83.24.0/2152.83.24.1 to 52.83.31.25452.83.31.2552,046
10152.83.32.0/2152.83.32.1 to 52.83.39.25452.83.39.2552,046
10252.83.40.0/2152.83.40.1 to 52.83.47.25452.83.47.2552,046
10352.83.48.0/2152.83.48.1 to 52.83.55.25452.83.55.2552,046
10452.83.56.0/2152.83.56.1 to 52.83.63.25452.83.63.2552,046
10552.83.64.0/2152.83.64.1 to 52.83.71.25452.83.71.2552,046
10652.83.72.0/2152.83.72.1 to 52.83.79.25452.83.79.2552,046
10752.83.80.0/2152.83.80.1 to 52.83.87.25452.83.87.2552,046
10852.83.88.0/2152.83.88.1 to 52.83.95.25452.83.95.2552,046
10952.83.96.0/2152.83.96.1 to 52.83.103.25452.83.103.2552,046
11052.83.104.0/2152.83.104.1 to 52.83.111.25452.83.111.2552,046
11152.83.112.0/2152.83.112.1 to 52.83.119.25452.83.119.2552,046
11252.83.120.0/2152.83.120.1 to 52.83.127.25452.83.127.2552,046
11352.83.128.0/2152.83.128.1 to 52.83.135.25452.83.135.2552,046
11452.83.136.0/2152.83.136.1 to 52.83.143.25452.83.143.2552,046
11552.83.144.0/2152.83.144.1 to 52.83.151.25452.83.151.2552,046
11652.83.152.0/2152.83.152.1 to 52.83.159.25452.83.159.2552,046
11752.83.160.0/2152.83.160.1 to 52.83.167.25452.83.167.2552,046
11852.83.168.0/2152.83.168.1 to 52.83.175.25452.83.175.2552,046
11952.83.176.0/2152.83.176.1 to 52.83.183.25452.83.183.2552,046
12052.83.184.0/2152.83.184.1 to 52.83.191.25452.83.191.2552,046
12152.83.192.0/2152.83.192.1 to 52.83.199.25452.83.199.2552,046
12252.83.200.0/2152.83.200.1 to 52.83.207.25452.83.207.2552,046
12352.83.208.0/2152.83.208.1 to 52.83.215.25452.83.215.2552,046
12452.83.216.0/2152.83.216.1 to 52.83.223.25452.83.223.2552,046
12552.83.224.0/2152.83.224.1 to 52.83.231.25452.83.231.2552,046
12652.83.232.0/2152.83.232.1 to 52.83.239.25452.83.239.2552,046
12752.83.240.0/2152.83.240.1 to 52.83.247.25452.83.247.2552,046
12852.83.248.0/2152.83.248.1 to 52.83.255.25452.83.255.2552,046

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.