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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.

Network14.224.0.0/12
Usable hosts1,048,574
Subnet mask255.240.0.0
Addresses1,048,576
Network address
14.224.0.0
Broadcast address
14.239.255.255
First usable
14.224.0.1
Last usable
14.239.255.254
Usable hosts
1,048,574 (1,048,576 less the network and broadcast addresses)
Subnet mask
255.240.0.0
Wildcard mask
0.15.255.255 (Cisco ACLs, OSPF)
Prefix length
/12
Type
Public public
Old class
A (default /8)
As numbers
Hex 0EE00000 · Integer 249561088 to 250609663
Reverse DNS zones
224.14.in-addr.arpa
225.14.in-addr.arpa
226.14.in-addr.arpa
227.14.in-addr.arpa
228.14.in-addr.arpa
229.14.in-addr.arpa
230.14.in-addr.arpa
231.14.in-addr.arpa
232.14.in-addr.arpa
233.14.in-addr.arpa
234.14.in-addr.arpa
235.14.in-addr.arpa
236.14.in-addr.arpa
237.14.in-addr.arpa
238.14.in-addr.arpa
239.14.in-addr.arpa
/12 is not on a 8-bit boundary, so it takes 16 /16 zones.
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address00001110.11100000.00000000.0000000014.224.0.0
Subnet mask11111111.11110000.00000000.00000000255.240.0.0
Network00001110.11100000.00000000.0000000014.224.0.0
Broadcast00001110.11101111.11111111.1111111114.239.255.255
Split into smaller subnets/19
/13 (2)/14 (4)/15 (8)/16 (16)/17 (32)/18 (64)/19 (128)/20 (256)/21 (512)/22 (1,024)/23 (2,048)/24 (4,096)

14.224.0.0/12 makes 128 subnets of /19.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
114.224.0.0/1914.224.0.1 to 14.224.31.25414.224.31.2558,190
214.224.32.0/1914.224.32.1 to 14.224.63.25414.224.63.2558,190
314.224.64.0/1914.224.64.1 to 14.224.95.25414.224.95.2558,190
414.224.96.0/1914.224.96.1 to 14.224.127.25414.224.127.2558,190
514.224.128.0/1914.224.128.1 to 14.224.159.25414.224.159.2558,190
614.224.160.0/1914.224.160.1 to 14.224.191.25414.224.191.2558,190
714.224.192.0/1914.224.192.1 to 14.224.223.25414.224.223.2558,190
814.224.224.0/1914.224.224.1 to 14.224.255.25414.224.255.2558,190
914.225.0.0/1914.225.0.1 to 14.225.31.25414.225.31.2558,190
1014.225.32.0/1914.225.32.1 to 14.225.63.25414.225.63.2558,190
1114.225.64.0/1914.225.64.1 to 14.225.95.25414.225.95.2558,190
1214.225.96.0/1914.225.96.1 to 14.225.127.25414.225.127.2558,190
1314.225.128.0/1914.225.128.1 to 14.225.159.25414.225.159.2558,190
1414.225.160.0/1914.225.160.1 to 14.225.191.25414.225.191.2558,190
1514.225.192.0/1914.225.192.1 to 14.225.223.25414.225.223.2558,190
1614.225.224.0/1914.225.224.1 to 14.225.255.25414.225.255.2558,190
1714.226.0.0/1914.226.0.1 to 14.226.31.25414.226.31.2558,190
1814.226.32.0/1914.226.32.1 to 14.226.63.25414.226.63.2558,190
1914.226.64.0/1914.226.64.1 to 14.226.95.25414.226.95.2558,190
2014.226.96.0/1914.226.96.1 to 14.226.127.25414.226.127.2558,190
2114.226.128.0/1914.226.128.1 to 14.226.159.25414.226.159.2558,190
2214.226.160.0/1914.226.160.1 to 14.226.191.25414.226.191.2558,190
2314.226.192.0/1914.226.192.1 to 14.226.223.25414.226.223.2558,190
2414.226.224.0/1914.226.224.1 to 14.226.255.25414.226.255.2558,190
2514.227.0.0/1914.227.0.1 to 14.227.31.25414.227.31.2558,190
2614.227.32.0/1914.227.32.1 to 14.227.63.25414.227.63.2558,190
2714.227.64.0/1914.227.64.1 to 14.227.95.25414.227.95.2558,190
2814.227.96.0/1914.227.96.1 to 14.227.127.25414.227.127.2558,190
2914.227.128.0/1914.227.128.1 to 14.227.159.25414.227.159.2558,190
3014.227.160.0/1914.227.160.1 to 14.227.191.25414.227.191.2558,190
3114.227.192.0/1914.227.192.1 to 14.227.223.25414.227.223.2558,190
3214.227.224.0/1914.227.224.1 to 14.227.255.25414.227.255.2558,190
3314.228.0.0/1914.228.0.1 to 14.228.31.25414.228.31.2558,190
3414.228.32.0/1914.228.32.1 to 14.228.63.25414.228.63.2558,190
3514.228.64.0/1914.228.64.1 to 14.228.95.25414.228.95.2558,190
3614.228.96.0/1914.228.96.1 to 14.228.127.25414.228.127.2558,190
3714.228.128.0/1914.228.128.1 to 14.228.159.25414.228.159.2558,190
3814.228.160.0/1914.228.160.1 to 14.228.191.25414.228.191.2558,190
3914.228.192.0/1914.228.192.1 to 14.228.223.25414.228.223.2558,190
4014.228.224.0/1914.228.224.1 to 14.228.255.25414.228.255.2558,190
4114.229.0.0/1914.229.0.1 to 14.229.31.25414.229.31.2558,190
4214.229.32.0/1914.229.32.1 to 14.229.63.25414.229.63.2558,190
4314.229.64.0/1914.229.64.1 to 14.229.95.25414.229.95.2558,190
4414.229.96.0/1914.229.96.1 to 14.229.127.25414.229.127.2558,190
4514.229.128.0/1914.229.128.1 to 14.229.159.25414.229.159.2558,190
4614.229.160.0/1914.229.160.1 to 14.229.191.25414.229.191.2558,190
4714.229.192.0/1914.229.192.1 to 14.229.223.25414.229.223.2558,190
4814.229.224.0/1914.229.224.1 to 14.229.255.25414.229.255.2558,190
4914.230.0.0/1914.230.0.1 to 14.230.31.25414.230.31.2558,190
5014.230.32.0/1914.230.32.1 to 14.230.63.25414.230.63.2558,190
5114.230.64.0/1914.230.64.1 to 14.230.95.25414.230.95.2558,190
5214.230.96.0/1914.230.96.1 to 14.230.127.25414.230.127.2558,190
5314.230.128.0/1914.230.128.1 to 14.230.159.25414.230.159.2558,190
5414.230.160.0/1914.230.160.1 to 14.230.191.25414.230.191.2558,190
5514.230.192.0/1914.230.192.1 to 14.230.223.25414.230.223.2558,190
5614.230.224.0/1914.230.224.1 to 14.230.255.25414.230.255.2558,190
5714.231.0.0/1914.231.0.1 to 14.231.31.25414.231.31.2558,190
5814.231.32.0/1914.231.32.1 to 14.231.63.25414.231.63.2558,190
5914.231.64.0/1914.231.64.1 to 14.231.95.25414.231.95.2558,190
6014.231.96.0/1914.231.96.1 to 14.231.127.25414.231.127.2558,190
6114.231.128.0/1914.231.128.1 to 14.231.159.25414.231.159.2558,190
6214.231.160.0/1914.231.160.1 to 14.231.191.25414.231.191.2558,190
6314.231.192.0/1914.231.192.1 to 14.231.223.25414.231.223.2558,190
6414.231.224.0/1914.231.224.1 to 14.231.255.25414.231.255.2558,190
6514.232.0.0/1914.232.0.1 to 14.232.31.25414.232.31.2558,190
6614.232.32.0/1914.232.32.1 to 14.232.63.25414.232.63.2558,190
6714.232.64.0/1914.232.64.1 to 14.232.95.25414.232.95.2558,190
6814.232.96.0/1914.232.96.1 to 14.232.127.25414.232.127.2558,190
6914.232.128.0/1914.232.128.1 to 14.232.159.25414.232.159.2558,190
7014.232.160.0/1914.232.160.1 to 14.232.191.25414.232.191.2558,190
7114.232.192.0/1914.232.192.1 to 14.232.223.25414.232.223.2558,190
7214.232.224.0/1914.232.224.1 to 14.232.255.25414.232.255.2558,190
7314.233.0.0/1914.233.0.1 to 14.233.31.25414.233.31.2558,190
7414.233.32.0/1914.233.32.1 to 14.233.63.25414.233.63.2558,190
7514.233.64.0/1914.233.64.1 to 14.233.95.25414.233.95.2558,190
7614.233.96.0/1914.233.96.1 to 14.233.127.25414.233.127.2558,190
7714.233.128.0/1914.233.128.1 to 14.233.159.25414.233.159.2558,190
7814.233.160.0/1914.233.160.1 to 14.233.191.25414.233.191.2558,190
7914.233.192.0/1914.233.192.1 to 14.233.223.25414.233.223.2558,190
8014.233.224.0/1914.233.224.1 to 14.233.255.25414.233.255.2558,190
8114.234.0.0/1914.234.0.1 to 14.234.31.25414.234.31.2558,190
8214.234.32.0/1914.234.32.1 to 14.234.63.25414.234.63.2558,190
8314.234.64.0/1914.234.64.1 to 14.234.95.25414.234.95.2558,190
8414.234.96.0/1914.234.96.1 to 14.234.127.25414.234.127.2558,190
8514.234.128.0/1914.234.128.1 to 14.234.159.25414.234.159.2558,190
8614.234.160.0/1914.234.160.1 to 14.234.191.25414.234.191.2558,190
8714.234.192.0/1914.234.192.1 to 14.234.223.25414.234.223.2558,190
8814.234.224.0/1914.234.224.1 to 14.234.255.25414.234.255.2558,190
8914.235.0.0/1914.235.0.1 to 14.235.31.25414.235.31.2558,190
9014.235.32.0/1914.235.32.1 to 14.235.63.25414.235.63.2558,190
9114.235.64.0/1914.235.64.1 to 14.235.95.25414.235.95.2558,190
9214.235.96.0/1914.235.96.1 to 14.235.127.25414.235.127.2558,190
9314.235.128.0/1914.235.128.1 to 14.235.159.25414.235.159.2558,190
9414.235.160.0/1914.235.160.1 to 14.235.191.25414.235.191.2558,190
9514.235.192.0/1914.235.192.1 to 14.235.223.25414.235.223.2558,190
9614.235.224.0/1914.235.224.1 to 14.235.255.25414.235.255.2558,190
9714.236.0.0/1914.236.0.1 to 14.236.31.25414.236.31.2558,190
9814.236.32.0/1914.236.32.1 to 14.236.63.25414.236.63.2558,190
9914.236.64.0/1914.236.64.1 to 14.236.95.25414.236.95.2558,190
10014.236.96.0/1914.236.96.1 to 14.236.127.25414.236.127.2558,190
10114.236.128.0/1914.236.128.1 to 14.236.159.25414.236.159.2558,190
10214.236.160.0/1914.236.160.1 to 14.236.191.25414.236.191.2558,190
10314.236.192.0/1914.236.192.1 to 14.236.223.25414.236.223.2558,190
10414.236.224.0/1914.236.224.1 to 14.236.255.25414.236.255.2558,190
10514.237.0.0/1914.237.0.1 to 14.237.31.25414.237.31.2558,190
10614.237.32.0/1914.237.32.1 to 14.237.63.25414.237.63.2558,190
10714.237.64.0/1914.237.64.1 to 14.237.95.25414.237.95.2558,190
10814.237.96.0/1914.237.96.1 to 14.237.127.25414.237.127.2558,190
10914.237.128.0/1914.237.128.1 to 14.237.159.25414.237.159.2558,190
11014.237.160.0/1914.237.160.1 to 14.237.191.25414.237.191.2558,190
11114.237.192.0/1914.237.192.1 to 14.237.223.25414.237.223.2558,190
11214.237.224.0/1914.237.224.1 to 14.237.255.25414.237.255.2558,190
11314.238.0.0/1914.238.0.1 to 14.238.31.25414.238.31.2558,190
11414.238.32.0/1914.238.32.1 to 14.238.63.25414.238.63.2558,190
11514.238.64.0/1914.238.64.1 to 14.238.95.25414.238.95.2558,190
11614.238.96.0/1914.238.96.1 to 14.238.127.25414.238.127.2558,190
11714.238.128.0/1914.238.128.1 to 14.238.159.25414.238.159.2558,190
11814.238.160.0/1914.238.160.1 to 14.238.191.25414.238.191.2558,190
11914.238.192.0/1914.238.192.1 to 14.238.223.25414.238.223.2558,190
12014.238.224.0/1914.238.224.1 to 14.238.255.25414.238.255.2558,190
12114.239.0.0/1914.239.0.1 to 14.239.31.25414.239.31.2558,190
12214.239.32.0/1914.239.32.1 to 14.239.63.25414.239.63.2558,190
12314.239.64.0/1914.239.64.1 to 14.239.95.25414.239.95.2558,190
12414.239.96.0/1914.239.96.1 to 14.239.127.25414.239.127.2558,190
12514.239.128.0/1914.239.128.1 to 14.239.159.25414.239.159.2558,190
12614.239.160.0/1914.239.160.1 to 14.239.191.25414.239.191.2558,190
12714.239.192.0/1914.239.192.1 to 14.239.223.25414.239.223.2558,190
12814.239.224.0/1914.239.224.1 to 14.239.255.25414.239.255.2558,190

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.