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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.

Network89.72.0.0/13
Usable hosts524,286
Subnet mask255.248.0.0
Addresses524,288
Network address
89.72.0.0
Broadcast address
89.79.255.255
First usable
89.72.0.1
Last usable
89.79.255.254
Usable hosts
524,286 (524,288 less the network and broadcast addresses)
Subnet mask
255.248.0.0
Wildcard mask
0.7.255.255 (Cisco ACLs, OSPF)
Prefix length
/13
Type
Public public
Old class
A (default /8)
As numbers
Hex 59480000 · Integer 1497890816 to 1498415103
Reverse DNS zones
72.89.in-addr.arpa
73.89.in-addr.arpa
74.89.in-addr.arpa
75.89.in-addr.arpa
76.89.in-addr.arpa
77.89.in-addr.arpa
78.89.in-addr.arpa
79.89.in-addr.arpa
/13 is not on a 8-bit boundary, so it takes 8 /16 zones.
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address01011001.01001000.00000000.0000000089.72.0.0
Subnet mask11111111.11111000.00000000.00000000255.248.0.0
Network01011001.01001000.00000000.0000000089.72.0.0
Broadcast01011001.01001111.11111111.1111111189.79.255.255
Split into smaller subnets/20

89.72.0.0/13 makes 128 subnets of /20.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
189.72.0.0/2089.72.0.1 to 89.72.15.25489.72.15.2554,094
289.72.16.0/2089.72.16.1 to 89.72.31.25489.72.31.2554,094
389.72.32.0/2089.72.32.1 to 89.72.47.25489.72.47.2554,094
489.72.48.0/2089.72.48.1 to 89.72.63.25489.72.63.2554,094
589.72.64.0/2089.72.64.1 to 89.72.79.25489.72.79.2554,094
689.72.80.0/2089.72.80.1 to 89.72.95.25489.72.95.2554,094
789.72.96.0/2089.72.96.1 to 89.72.111.25489.72.111.2554,094
889.72.112.0/2089.72.112.1 to 89.72.127.25489.72.127.2554,094
989.72.128.0/2089.72.128.1 to 89.72.143.25489.72.143.2554,094
1089.72.144.0/2089.72.144.1 to 89.72.159.25489.72.159.2554,094
1189.72.160.0/2089.72.160.1 to 89.72.175.25489.72.175.2554,094
1289.72.176.0/2089.72.176.1 to 89.72.191.25489.72.191.2554,094
1389.72.192.0/2089.72.192.1 to 89.72.207.25489.72.207.2554,094
1489.72.208.0/2089.72.208.1 to 89.72.223.25489.72.223.2554,094
1589.72.224.0/2089.72.224.1 to 89.72.239.25489.72.239.2554,094
1689.72.240.0/2089.72.240.1 to 89.72.255.25489.72.255.2554,094
1789.73.0.0/2089.73.0.1 to 89.73.15.25489.73.15.2554,094
1889.73.16.0/2089.73.16.1 to 89.73.31.25489.73.31.2554,094
1989.73.32.0/2089.73.32.1 to 89.73.47.25489.73.47.2554,094
2089.73.48.0/2089.73.48.1 to 89.73.63.25489.73.63.2554,094
2189.73.64.0/2089.73.64.1 to 89.73.79.25489.73.79.2554,094
2289.73.80.0/2089.73.80.1 to 89.73.95.25489.73.95.2554,094
2389.73.96.0/2089.73.96.1 to 89.73.111.25489.73.111.2554,094
2489.73.112.0/2089.73.112.1 to 89.73.127.25489.73.127.2554,094
2589.73.128.0/2089.73.128.1 to 89.73.143.25489.73.143.2554,094
2689.73.144.0/2089.73.144.1 to 89.73.159.25489.73.159.2554,094
2789.73.160.0/2089.73.160.1 to 89.73.175.25489.73.175.2554,094
2889.73.176.0/2089.73.176.1 to 89.73.191.25489.73.191.2554,094
2989.73.192.0/2089.73.192.1 to 89.73.207.25489.73.207.2554,094
3089.73.208.0/2089.73.208.1 to 89.73.223.25489.73.223.2554,094
3189.73.224.0/2089.73.224.1 to 89.73.239.25489.73.239.2554,094
3289.73.240.0/2089.73.240.1 to 89.73.255.25489.73.255.2554,094
3389.74.0.0/2089.74.0.1 to 89.74.15.25489.74.15.2554,094
3489.74.16.0/2089.74.16.1 to 89.74.31.25489.74.31.2554,094
3589.74.32.0/2089.74.32.1 to 89.74.47.25489.74.47.2554,094
3689.74.48.0/2089.74.48.1 to 89.74.63.25489.74.63.2554,094
3789.74.64.0/2089.74.64.1 to 89.74.79.25489.74.79.2554,094
3889.74.80.0/2089.74.80.1 to 89.74.95.25489.74.95.2554,094
3989.74.96.0/2089.74.96.1 to 89.74.111.25489.74.111.2554,094
4089.74.112.0/2089.74.112.1 to 89.74.127.25489.74.127.2554,094
4189.74.128.0/2089.74.128.1 to 89.74.143.25489.74.143.2554,094
4289.74.144.0/2089.74.144.1 to 89.74.159.25489.74.159.2554,094
4389.74.160.0/2089.74.160.1 to 89.74.175.25489.74.175.2554,094
4489.74.176.0/2089.74.176.1 to 89.74.191.25489.74.191.2554,094
4589.74.192.0/2089.74.192.1 to 89.74.207.25489.74.207.2554,094
4689.74.208.0/2089.74.208.1 to 89.74.223.25489.74.223.2554,094
4789.74.224.0/2089.74.224.1 to 89.74.239.25489.74.239.2554,094
4889.74.240.0/2089.74.240.1 to 89.74.255.25489.74.255.2554,094
4989.75.0.0/2089.75.0.1 to 89.75.15.25489.75.15.2554,094
5089.75.16.0/2089.75.16.1 to 89.75.31.25489.75.31.2554,094
5189.75.32.0/2089.75.32.1 to 89.75.47.25489.75.47.2554,094
5289.75.48.0/2089.75.48.1 to 89.75.63.25489.75.63.2554,094
5389.75.64.0/2089.75.64.1 to 89.75.79.25489.75.79.2554,094
5489.75.80.0/2089.75.80.1 to 89.75.95.25489.75.95.2554,094
5589.75.96.0/2089.75.96.1 to 89.75.111.25489.75.111.2554,094
5689.75.112.0/2089.75.112.1 to 89.75.127.25489.75.127.2554,094
5789.75.128.0/2089.75.128.1 to 89.75.143.25489.75.143.2554,094
5889.75.144.0/2089.75.144.1 to 89.75.159.25489.75.159.2554,094
5989.75.160.0/2089.75.160.1 to 89.75.175.25489.75.175.2554,094
6089.75.176.0/2089.75.176.1 to 89.75.191.25489.75.191.2554,094
6189.75.192.0/2089.75.192.1 to 89.75.207.25489.75.207.2554,094
6289.75.208.0/2089.75.208.1 to 89.75.223.25489.75.223.2554,094
6389.75.224.0/2089.75.224.1 to 89.75.239.25489.75.239.2554,094
6489.75.240.0/2089.75.240.1 to 89.75.255.25489.75.255.2554,094
6589.76.0.0/2089.76.0.1 to 89.76.15.25489.76.15.2554,094
6689.76.16.0/2089.76.16.1 to 89.76.31.25489.76.31.2554,094
6789.76.32.0/2089.76.32.1 to 89.76.47.25489.76.47.2554,094
6889.76.48.0/2089.76.48.1 to 89.76.63.25489.76.63.2554,094
6989.76.64.0/2089.76.64.1 to 89.76.79.25489.76.79.2554,094
7089.76.80.0/2089.76.80.1 to 89.76.95.25489.76.95.2554,094
7189.76.96.0/2089.76.96.1 to 89.76.111.25489.76.111.2554,094
7289.76.112.0/2089.76.112.1 to 89.76.127.25489.76.127.2554,094
7389.76.128.0/2089.76.128.1 to 89.76.143.25489.76.143.2554,094
7489.76.144.0/2089.76.144.1 to 89.76.159.25489.76.159.2554,094
7589.76.160.0/2089.76.160.1 to 89.76.175.25489.76.175.2554,094
7689.76.176.0/2089.76.176.1 to 89.76.191.25489.76.191.2554,094
7789.76.192.0/2089.76.192.1 to 89.76.207.25489.76.207.2554,094
7889.76.208.0/2089.76.208.1 to 89.76.223.25489.76.223.2554,094
7989.76.224.0/2089.76.224.1 to 89.76.239.25489.76.239.2554,094
8089.76.240.0/2089.76.240.1 to 89.76.255.25489.76.255.2554,094
8189.77.0.0/2089.77.0.1 to 89.77.15.25489.77.15.2554,094
8289.77.16.0/2089.77.16.1 to 89.77.31.25489.77.31.2554,094
8389.77.32.0/2089.77.32.1 to 89.77.47.25489.77.47.2554,094
8489.77.48.0/2089.77.48.1 to 89.77.63.25489.77.63.2554,094
8589.77.64.0/2089.77.64.1 to 89.77.79.25489.77.79.2554,094
8689.77.80.0/2089.77.80.1 to 89.77.95.25489.77.95.2554,094
8789.77.96.0/2089.77.96.1 to 89.77.111.25489.77.111.2554,094
8889.77.112.0/2089.77.112.1 to 89.77.127.25489.77.127.2554,094
8989.77.128.0/2089.77.128.1 to 89.77.143.25489.77.143.2554,094
9089.77.144.0/2089.77.144.1 to 89.77.159.25489.77.159.2554,094
9189.77.160.0/2089.77.160.1 to 89.77.175.25489.77.175.2554,094
9289.77.176.0/2089.77.176.1 to 89.77.191.25489.77.191.2554,094
9389.77.192.0/2089.77.192.1 to 89.77.207.25489.77.207.2554,094
9489.77.208.0/2089.77.208.1 to 89.77.223.25489.77.223.2554,094
9589.77.224.0/2089.77.224.1 to 89.77.239.25489.77.239.2554,094
9689.77.240.0/2089.77.240.1 to 89.77.255.25489.77.255.2554,094
9789.78.0.0/2089.78.0.1 to 89.78.15.25489.78.15.2554,094
9889.78.16.0/2089.78.16.1 to 89.78.31.25489.78.31.2554,094
9989.78.32.0/2089.78.32.1 to 89.78.47.25489.78.47.2554,094
10089.78.48.0/2089.78.48.1 to 89.78.63.25489.78.63.2554,094
10189.78.64.0/2089.78.64.1 to 89.78.79.25489.78.79.2554,094
10289.78.80.0/2089.78.80.1 to 89.78.95.25489.78.95.2554,094
10389.78.96.0/2089.78.96.1 to 89.78.111.25489.78.111.2554,094
10489.78.112.0/2089.78.112.1 to 89.78.127.25489.78.127.2554,094
10589.78.128.0/2089.78.128.1 to 89.78.143.25489.78.143.2554,094
10689.78.144.0/2089.78.144.1 to 89.78.159.25489.78.159.2554,094
10789.78.160.0/2089.78.160.1 to 89.78.175.25489.78.175.2554,094
10889.78.176.0/2089.78.176.1 to 89.78.191.25489.78.191.2554,094
10989.78.192.0/2089.78.192.1 to 89.78.207.25489.78.207.2554,094
11089.78.208.0/2089.78.208.1 to 89.78.223.25489.78.223.2554,094
11189.78.224.0/2089.78.224.1 to 89.78.239.25489.78.239.2554,094
11289.78.240.0/2089.78.240.1 to 89.78.255.25489.78.255.2554,094
11389.79.0.0/2089.79.0.1 to 89.79.15.25489.79.15.2554,094
11489.79.16.0/2089.79.16.1 to 89.79.31.25489.79.31.2554,094
11589.79.32.0/2089.79.32.1 to 89.79.47.25489.79.47.2554,094
11689.79.48.0/2089.79.48.1 to 89.79.63.25489.79.63.2554,094
11789.79.64.0/2089.79.64.1 to 89.79.79.25489.79.79.2554,094
11889.79.80.0/2089.79.80.1 to 89.79.95.25489.79.95.2554,094
11989.79.96.0/2089.79.96.1 to 89.79.111.25489.79.111.2554,094
12089.79.112.0/2089.79.112.1 to 89.79.127.25489.79.127.2554,094
12189.79.128.0/2089.79.128.1 to 89.79.143.25489.79.143.2554,094
12289.79.144.0/2089.79.144.1 to 89.79.159.25489.79.159.2554,094
12389.79.160.0/2089.79.160.1 to 89.79.175.25489.79.175.2554,094
12489.79.176.0/2089.79.176.1 to 89.79.191.25489.79.191.2554,094
12589.79.192.0/2089.79.192.1 to 89.79.207.25489.79.207.2554,094
12689.79.208.0/2089.79.208.1 to 89.79.223.25489.79.223.2554,094
12789.79.224.0/2089.79.224.1 to 89.79.239.25489.79.239.2554,094
12889.79.240.0/2089.79.240.1 to 89.79.255.25489.79.255.2554,094

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