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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.

Network89.0.0.0/8
Usable hosts16,777,214
Subnet mask255.0.0.0
Addresses16,777,216
Network address
89.0.0.0
Broadcast address
89.255.255.255
First usable
89.0.0.1
Last usable
89.255.255.254
Usable hosts
16,777,214 (16,777,216 less the network and broadcast addresses)
Subnet mask
255.0.0.0
Wildcard mask
0.255.255.255 (Cisco ACLs, OSPF)
Prefix length
/8
Type
Public public
Old class
A (default /8)
As numbers
Hex 59000000 · Integer 1493172224 to 1509949439
Reverse DNS zone
89.in-addr.arpa
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address01011001..00000000.00000000.0000000089.0.0.0
Subnet mask11111111..00000000.00000000.00000000255.0.0.0
Network01011001..00000000.00000000.0000000089.0.0.0
Broadcast01011001..11111111.11111111.1111111189.255.255.255
Split into smaller subnets/14

89.0.0.0/8 makes 64 subnets of /14.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
189.0.0.0/1489.0.0.1 to 89.3.255.25489.3.255.255262,142
289.4.0.0/1489.4.0.1 to 89.7.255.25489.7.255.255262,142
389.8.0.0/1489.8.0.1 to 89.11.255.25489.11.255.255262,142
489.12.0.0/1489.12.0.1 to 89.15.255.25489.15.255.255262,142
589.16.0.0/1489.16.0.1 to 89.19.255.25489.19.255.255262,142
689.20.0.0/1489.20.0.1 to 89.23.255.25489.23.255.255262,142
789.24.0.0/1489.24.0.1 to 89.27.255.25489.27.255.255262,142
889.28.0.0/1489.28.0.1 to 89.31.255.25489.31.255.255262,142
989.32.0.0/1489.32.0.1 to 89.35.255.25489.35.255.255262,142
1089.36.0.0/1489.36.0.1 to 89.39.255.25489.39.255.255262,142
1189.40.0.0/1489.40.0.1 to 89.43.255.25489.43.255.255262,142
1289.44.0.0/1489.44.0.1 to 89.47.255.25489.47.255.255262,142
1389.48.0.0/1489.48.0.1 to 89.51.255.25489.51.255.255262,142
1489.52.0.0/1489.52.0.1 to 89.55.255.25489.55.255.255262,142
1589.56.0.0/1489.56.0.1 to 89.59.255.25489.59.255.255262,142
1689.60.0.0/1489.60.0.1 to 89.63.255.25489.63.255.255262,142
1789.64.0.0/1489.64.0.1 to 89.67.255.25489.67.255.255262,142
1889.68.0.0/1489.68.0.1 to 89.71.255.25489.71.255.255262,142
1989.72.0.0/1489.72.0.1 to 89.75.255.25489.75.255.255262,142
2089.76.0.0/1489.76.0.1 to 89.79.255.25489.79.255.255262,142
2189.80.0.0/1489.80.0.1 to 89.83.255.25489.83.255.255262,142
2289.84.0.0/1489.84.0.1 to 89.87.255.25489.87.255.255262,142
2389.88.0.0/1489.88.0.1 to 89.91.255.25489.91.255.255262,142
2489.92.0.0/1489.92.0.1 to 89.95.255.25489.95.255.255262,142
2589.96.0.0/1489.96.0.1 to 89.99.255.25489.99.255.255262,142
2689.100.0.0/1489.100.0.1 to 89.103.255.25489.103.255.255262,142
2789.104.0.0/1489.104.0.1 to 89.107.255.25489.107.255.255262,142
2889.108.0.0/1489.108.0.1 to 89.111.255.25489.111.255.255262,142
2989.112.0.0/1489.112.0.1 to 89.115.255.25489.115.255.255262,142
3089.116.0.0/1489.116.0.1 to 89.119.255.25489.119.255.255262,142
3189.120.0.0/1489.120.0.1 to 89.123.255.25489.123.255.255262,142
3289.124.0.0/1489.124.0.1 to 89.127.255.25489.127.255.255262,142
3389.128.0.0/1489.128.0.1 to 89.131.255.25489.131.255.255262,142
3489.132.0.0/1489.132.0.1 to 89.135.255.25489.135.255.255262,142
3589.136.0.0/1489.136.0.1 to 89.139.255.25489.139.255.255262,142
3689.140.0.0/1489.140.0.1 to 89.143.255.25489.143.255.255262,142
3789.144.0.0/1489.144.0.1 to 89.147.255.25489.147.255.255262,142
3889.148.0.0/1489.148.0.1 to 89.151.255.25489.151.255.255262,142
3989.152.0.0/1489.152.0.1 to 89.155.255.25489.155.255.255262,142
4089.156.0.0/1489.156.0.1 to 89.159.255.25489.159.255.255262,142
4189.160.0.0/1489.160.0.1 to 89.163.255.25489.163.255.255262,142
4289.164.0.0/1489.164.0.1 to 89.167.255.25489.167.255.255262,142
4389.168.0.0/1489.168.0.1 to 89.171.255.25489.171.255.255262,142
4489.172.0.0/1489.172.0.1 to 89.175.255.25489.175.255.255262,142
4589.176.0.0/1489.176.0.1 to 89.179.255.25489.179.255.255262,142
4689.180.0.0/1489.180.0.1 to 89.183.255.25489.183.255.255262,142
4789.184.0.0/1489.184.0.1 to 89.187.255.25489.187.255.255262,142
4889.188.0.0/1489.188.0.1 to 89.191.255.25489.191.255.255262,142
4989.192.0.0/1489.192.0.1 to 89.195.255.25489.195.255.255262,142
5089.196.0.0/1489.196.0.1 to 89.199.255.25489.199.255.255262,142
5189.200.0.0/1489.200.0.1 to 89.203.255.25489.203.255.255262,142
5289.204.0.0/1489.204.0.1 to 89.207.255.25489.207.255.255262,142
5389.208.0.0/1489.208.0.1 to 89.211.255.25489.211.255.255262,142
5489.212.0.0/1489.212.0.1 to 89.215.255.25489.215.255.255262,142
5589.216.0.0/1489.216.0.1 to 89.219.255.25489.219.255.255262,142
5689.220.0.0/1489.220.0.1 to 89.223.255.25489.223.255.255262,142
5789.224.0.0/1489.224.0.1 to 89.227.255.25489.227.255.255262,142
5889.228.0.0/1489.228.0.1 to 89.231.255.25489.231.255.255262,142
5989.232.0.0/1489.232.0.1 to 89.235.255.25489.235.255.255262,142
6089.236.0.0/1489.236.0.1 to 89.239.255.25489.239.255.255262,142
6189.240.0.0/1489.240.0.1 to 89.243.255.25489.243.255.255262,142
6289.244.0.0/1489.244.0.1 to 89.247.255.25489.247.255.255262,142
6389.248.0.0/1489.248.0.1 to 89.251.255.25489.251.255.255262,142
6489.252.0.0/1489.252.0.1 to 89.255.255.25489.255.255.255262,142

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