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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.

Network14.53.0.0/16
Usable hosts65,534
Subnet mask255.255.0.0
Addresses65,536
Network address
14.53.0.0
Broadcast address
14.53.255.255
First usable
14.53.0.1
Last usable
14.53.255.254
Usable hosts
65,534 (65,536 less the network and broadcast addresses)
Subnet mask
255.255.0.0
Wildcard mask
0.0.255.255 (Cisco ACLs, OSPF)
Prefix length
/16
Type
Public public
Old class
A (default /8)
As numbers
Hex 0E350000 · Integer 238354432 to 238419967
Reverse DNS zone
53.14.in-addr.arpa
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address00001110.00110101..00000000.0000000014.53.0.0
Subnet mask11111111.11111111..00000000.00000000255.255.0.0
Network00001110.00110101..00000000.0000000014.53.0.0
Broadcast00001110.00110101..11111111.1111111114.53.255.255
Split into smaller subnets/22
/17 (2)/18 (4)/19 (8)/20 (16)/21 (32)/22 (64)/23 (128)/24 (256)/25 (512)/26 (1,024)/27 (2,048)/28 (4,096)

14.53.0.0/16 makes 64 subnets of /22.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
114.53.0.0/2214.53.0.1 to 14.53.3.25414.53.3.2551,022
214.53.4.0/2214.53.4.1 to 14.53.7.25414.53.7.2551,022
314.53.8.0/2214.53.8.1 to 14.53.11.25414.53.11.2551,022
414.53.12.0/2214.53.12.1 to 14.53.15.25414.53.15.2551,022
514.53.16.0/2214.53.16.1 to 14.53.19.25414.53.19.2551,022
614.53.20.0/2214.53.20.1 to 14.53.23.25414.53.23.2551,022
714.53.24.0/2214.53.24.1 to 14.53.27.25414.53.27.2551,022
814.53.28.0/2214.53.28.1 to 14.53.31.25414.53.31.2551,022
914.53.32.0/2214.53.32.1 to 14.53.35.25414.53.35.2551,022
1014.53.36.0/2214.53.36.1 to 14.53.39.25414.53.39.2551,022
1114.53.40.0/2214.53.40.1 to 14.53.43.25414.53.43.2551,022
1214.53.44.0/2214.53.44.1 to 14.53.47.25414.53.47.2551,022
1314.53.48.0/2214.53.48.1 to 14.53.51.25414.53.51.2551,022
1414.53.52.0/2214.53.52.1 to 14.53.55.25414.53.55.2551,022
1514.53.56.0/2214.53.56.1 to 14.53.59.25414.53.59.2551,022
1614.53.60.0/2214.53.60.1 to 14.53.63.25414.53.63.2551,022
1714.53.64.0/2214.53.64.1 to 14.53.67.25414.53.67.2551,022
1814.53.68.0/2214.53.68.1 to 14.53.71.25414.53.71.2551,022
1914.53.72.0/2214.53.72.1 to 14.53.75.25414.53.75.2551,022
2014.53.76.0/2214.53.76.1 to 14.53.79.25414.53.79.2551,022
2114.53.80.0/2214.53.80.1 to 14.53.83.25414.53.83.2551,022
2214.53.84.0/2214.53.84.1 to 14.53.87.25414.53.87.2551,022
2314.53.88.0/2214.53.88.1 to 14.53.91.25414.53.91.2551,022
2414.53.92.0/2214.53.92.1 to 14.53.95.25414.53.95.2551,022
2514.53.96.0/2214.53.96.1 to 14.53.99.25414.53.99.2551,022
2614.53.100.0/2214.53.100.1 to 14.53.103.25414.53.103.2551,022
2714.53.104.0/2214.53.104.1 to 14.53.107.25414.53.107.2551,022
2814.53.108.0/2214.53.108.1 to 14.53.111.25414.53.111.2551,022
2914.53.112.0/2214.53.112.1 to 14.53.115.25414.53.115.2551,022
3014.53.116.0/2214.53.116.1 to 14.53.119.25414.53.119.2551,022
3114.53.120.0/2214.53.120.1 to 14.53.123.25414.53.123.2551,022
3214.53.124.0/2214.53.124.1 to 14.53.127.25414.53.127.2551,022
3314.53.128.0/2214.53.128.1 to 14.53.131.25414.53.131.2551,022
3414.53.132.0/2214.53.132.1 to 14.53.135.25414.53.135.2551,022
3514.53.136.0/2214.53.136.1 to 14.53.139.25414.53.139.2551,022
3614.53.140.0/2214.53.140.1 to 14.53.143.25414.53.143.2551,022
3714.53.144.0/2214.53.144.1 to 14.53.147.25414.53.147.2551,022
3814.53.148.0/2214.53.148.1 to 14.53.151.25414.53.151.2551,022
3914.53.152.0/2214.53.152.1 to 14.53.155.25414.53.155.2551,022
4014.53.156.0/2214.53.156.1 to 14.53.159.25414.53.159.2551,022
4114.53.160.0/2214.53.160.1 to 14.53.163.25414.53.163.2551,022
4214.53.164.0/2214.53.164.1 to 14.53.167.25414.53.167.2551,022
4314.53.168.0/2214.53.168.1 to 14.53.171.25414.53.171.2551,022
4414.53.172.0/2214.53.172.1 to 14.53.175.25414.53.175.2551,022
4514.53.176.0/2214.53.176.1 to 14.53.179.25414.53.179.2551,022
4614.53.180.0/2214.53.180.1 to 14.53.183.25414.53.183.2551,022
4714.53.184.0/2214.53.184.1 to 14.53.187.25414.53.187.2551,022
4814.53.188.0/2214.53.188.1 to 14.53.191.25414.53.191.2551,022
4914.53.192.0/2214.53.192.1 to 14.53.195.25414.53.195.2551,022
5014.53.196.0/2214.53.196.1 to 14.53.199.25414.53.199.2551,022
5114.53.200.0/2214.53.200.1 to 14.53.203.25414.53.203.2551,022
5214.53.204.0/2214.53.204.1 to 14.53.207.25414.53.207.2551,022
5314.53.208.0/2214.53.208.1 to 14.53.211.25414.53.211.2551,022
5414.53.212.0/2214.53.212.1 to 14.53.215.25414.53.215.2551,022
5514.53.216.0/2214.53.216.1 to 14.53.219.25414.53.219.2551,022
5614.53.220.0/2214.53.220.1 to 14.53.223.25414.53.223.2551,022
5714.53.224.0/2214.53.224.1 to 14.53.227.25414.53.227.2551,022
5814.53.228.0/2214.53.228.1 to 14.53.231.25414.53.231.2551,022
5914.53.232.0/2214.53.232.1 to 14.53.235.25414.53.235.2551,022
6014.53.236.0/2214.53.236.1 to 14.53.239.25414.53.239.2551,022
6114.53.240.0/2214.53.240.1 to 14.53.243.25414.53.243.2551,022
6214.53.244.0/2214.53.244.1 to 14.53.247.25414.53.247.2551,022
6314.53.248.0/2214.53.248.1 to 14.53.251.25414.53.251.2551,022
6414.53.252.0/2214.53.252.1 to 14.53.255.25414.53.255.2551,022

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.