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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.

Network89.3.90.0/23
Usable hosts510
Subnet mask255.255.254.0
Addresses512
Network address
89.3.90.0
Broadcast address
89.3.91.255
First usable
89.3.90.1
Last usable
89.3.91.254
Usable hosts
510 (512 less the network and broadcast addresses)
Subnet mask
255.255.254.0
Wildcard mask
0.0.1.255 (Cisco ACLs, OSPF)
Prefix length
/23
Type
Public public
Old class
A (default /8)
As numbers
Hex 59035A00 · Integer 1493391872 to 1493392383
Reverse DNS zones
90.3.89.in-addr.arpa
91.3.89.in-addr.arpa
/23 is not on a 8-bit boundary, so it takes 2 /24 zones.
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address01011001.00000011.01011010.0000000089.3.90.0
Subnet mask11111111.11111111.11111110.00000000255.255.254.0
Network01011001.00000011.01011010.0000000089.3.90.0
Broadcast01011001.00000011.01011011.1111111189.3.91.255
Split into smaller subnets/30

89.3.90.0/23 makes 128 subnets of /30.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
189.3.90.0/3089.3.90.1 to 89.3.90.289.3.90.32
289.3.90.4/3089.3.90.5 to 89.3.90.689.3.90.72
389.3.90.8/3089.3.90.9 to 89.3.90.1089.3.90.112
489.3.90.12/3089.3.90.13 to 89.3.90.1489.3.90.152
589.3.90.16/3089.3.90.17 to 89.3.90.1889.3.90.192
689.3.90.20/3089.3.90.21 to 89.3.90.2289.3.90.232
789.3.90.24/3089.3.90.25 to 89.3.90.2689.3.90.272
889.3.90.28/3089.3.90.29 to 89.3.90.3089.3.90.312
989.3.90.32/3089.3.90.33 to 89.3.90.3489.3.90.352
1089.3.90.36/3089.3.90.37 to 89.3.90.3889.3.90.392
1189.3.90.40/3089.3.90.41 to 89.3.90.4289.3.90.432
1289.3.90.44/3089.3.90.45 to 89.3.90.4689.3.90.472
1389.3.90.48/3089.3.90.49 to 89.3.90.5089.3.90.512
1489.3.90.52/3089.3.90.53 to 89.3.90.5489.3.90.552
1589.3.90.56/3089.3.90.57 to 89.3.90.5889.3.90.592
1689.3.90.60/3089.3.90.61 to 89.3.90.6289.3.90.632
1789.3.90.64/3089.3.90.65 to 89.3.90.6689.3.90.672
1889.3.90.68/3089.3.90.69 to 89.3.90.7089.3.90.712
1989.3.90.72/3089.3.90.73 to 89.3.90.7489.3.90.752
2089.3.90.76/3089.3.90.77 to 89.3.90.7889.3.90.792
2189.3.90.80/3089.3.90.81 to 89.3.90.8289.3.90.832
2289.3.90.84/3089.3.90.85 to 89.3.90.8689.3.90.872
2389.3.90.88/3089.3.90.89 to 89.3.90.9089.3.90.912
2489.3.90.92/3089.3.90.93 to 89.3.90.9489.3.90.952
2589.3.90.96/3089.3.90.97 to 89.3.90.9889.3.90.992
2689.3.90.100/3089.3.90.101 to 89.3.90.10289.3.90.1032
2789.3.90.104/3089.3.90.105 to 89.3.90.10689.3.90.1072
2889.3.90.108/3089.3.90.109 to 89.3.90.11089.3.90.1112
2989.3.90.112/3089.3.90.113 to 89.3.90.11489.3.90.1152
3089.3.90.116/3089.3.90.117 to 89.3.90.11889.3.90.1192
3189.3.90.120/3089.3.90.121 to 89.3.90.12289.3.90.1232
3289.3.90.124/3089.3.90.125 to 89.3.90.12689.3.90.1272
3389.3.90.128/3089.3.90.129 to 89.3.90.13089.3.90.1312
3489.3.90.132/3089.3.90.133 to 89.3.90.13489.3.90.1352
3589.3.90.136/3089.3.90.137 to 89.3.90.13889.3.90.1392
3689.3.90.140/3089.3.90.141 to 89.3.90.14289.3.90.1432
3789.3.90.144/3089.3.90.145 to 89.3.90.14689.3.90.1472
3889.3.90.148/3089.3.90.149 to 89.3.90.15089.3.90.1512
3989.3.90.152/3089.3.90.153 to 89.3.90.15489.3.90.1552
4089.3.90.156/3089.3.90.157 to 89.3.90.15889.3.90.1592
4189.3.90.160/3089.3.90.161 to 89.3.90.16289.3.90.1632
4289.3.90.164/3089.3.90.165 to 89.3.90.16689.3.90.1672
4389.3.90.168/3089.3.90.169 to 89.3.90.17089.3.90.1712
4489.3.90.172/3089.3.90.173 to 89.3.90.17489.3.90.1752
4589.3.90.176/3089.3.90.177 to 89.3.90.17889.3.90.1792
4689.3.90.180/3089.3.90.181 to 89.3.90.18289.3.90.1832
4789.3.90.184/3089.3.90.185 to 89.3.90.18689.3.90.1872
4889.3.90.188/3089.3.90.189 to 89.3.90.19089.3.90.1912
4989.3.90.192/3089.3.90.193 to 89.3.90.19489.3.90.1952
5089.3.90.196/3089.3.90.197 to 89.3.90.19889.3.90.1992
5189.3.90.200/3089.3.90.201 to 89.3.90.20289.3.90.2032
5289.3.90.204/3089.3.90.205 to 89.3.90.20689.3.90.2072
5389.3.90.208/3089.3.90.209 to 89.3.90.21089.3.90.2112
5489.3.90.212/3089.3.90.213 to 89.3.90.21489.3.90.2152
5589.3.90.216/3089.3.90.217 to 89.3.90.21889.3.90.2192
5689.3.90.220/3089.3.90.221 to 89.3.90.22289.3.90.2232
5789.3.90.224/3089.3.90.225 to 89.3.90.22689.3.90.2272
5889.3.90.228/3089.3.90.229 to 89.3.90.23089.3.90.2312
5989.3.90.232/3089.3.90.233 to 89.3.90.23489.3.90.2352
6089.3.90.236/3089.3.90.237 to 89.3.90.23889.3.90.2392
6189.3.90.240/3089.3.90.241 to 89.3.90.24289.3.90.2432
6289.3.90.244/3089.3.90.245 to 89.3.90.24689.3.90.2472
6389.3.90.248/3089.3.90.249 to 89.3.90.25089.3.90.2512
6489.3.90.252/3089.3.90.253 to 89.3.90.25489.3.90.2552
6589.3.91.0/3089.3.91.1 to 89.3.91.289.3.91.32
6689.3.91.4/3089.3.91.5 to 89.3.91.689.3.91.72
6789.3.91.8/3089.3.91.9 to 89.3.91.1089.3.91.112
6889.3.91.12/3089.3.91.13 to 89.3.91.1489.3.91.152
6989.3.91.16/3089.3.91.17 to 89.3.91.1889.3.91.192
7089.3.91.20/3089.3.91.21 to 89.3.91.2289.3.91.232
7189.3.91.24/3089.3.91.25 to 89.3.91.2689.3.91.272
7289.3.91.28/3089.3.91.29 to 89.3.91.3089.3.91.312
7389.3.91.32/3089.3.91.33 to 89.3.91.3489.3.91.352
7489.3.91.36/3089.3.91.37 to 89.3.91.3889.3.91.392
7589.3.91.40/3089.3.91.41 to 89.3.91.4289.3.91.432
7689.3.91.44/3089.3.91.45 to 89.3.91.4689.3.91.472
7789.3.91.48/3089.3.91.49 to 89.3.91.5089.3.91.512
7889.3.91.52/3089.3.91.53 to 89.3.91.5489.3.91.552
7989.3.91.56/3089.3.91.57 to 89.3.91.5889.3.91.592
8089.3.91.60/3089.3.91.61 to 89.3.91.6289.3.91.632
8189.3.91.64/3089.3.91.65 to 89.3.91.6689.3.91.672
8289.3.91.68/3089.3.91.69 to 89.3.91.7089.3.91.712
8389.3.91.72/3089.3.91.73 to 89.3.91.7489.3.91.752
8489.3.91.76/3089.3.91.77 to 89.3.91.7889.3.91.792
8589.3.91.80/3089.3.91.81 to 89.3.91.8289.3.91.832
8689.3.91.84/3089.3.91.85 to 89.3.91.8689.3.91.872
8789.3.91.88/3089.3.91.89 to 89.3.91.9089.3.91.912
8889.3.91.92/3089.3.91.93 to 89.3.91.9489.3.91.952
8989.3.91.96/3089.3.91.97 to 89.3.91.9889.3.91.992
9089.3.91.100/3089.3.91.101 to 89.3.91.10289.3.91.1032
9189.3.91.104/3089.3.91.105 to 89.3.91.10689.3.91.1072
9289.3.91.108/3089.3.91.109 to 89.3.91.11089.3.91.1112
9389.3.91.112/3089.3.91.113 to 89.3.91.11489.3.91.1152
9489.3.91.116/3089.3.91.117 to 89.3.91.11889.3.91.1192
9589.3.91.120/3089.3.91.121 to 89.3.91.12289.3.91.1232
9689.3.91.124/3089.3.91.125 to 89.3.91.12689.3.91.1272
9789.3.91.128/3089.3.91.129 to 89.3.91.13089.3.91.1312
9889.3.91.132/3089.3.91.133 to 89.3.91.13489.3.91.1352
9989.3.91.136/3089.3.91.137 to 89.3.91.13889.3.91.1392
10089.3.91.140/3089.3.91.141 to 89.3.91.14289.3.91.1432
10189.3.91.144/3089.3.91.145 to 89.3.91.14689.3.91.1472
10289.3.91.148/3089.3.91.149 to 89.3.91.15089.3.91.1512
10389.3.91.152/3089.3.91.153 to 89.3.91.15489.3.91.1552
10489.3.91.156/3089.3.91.157 to 89.3.91.15889.3.91.1592
10589.3.91.160/3089.3.91.161 to 89.3.91.16289.3.91.1632
10689.3.91.164/3089.3.91.165 to 89.3.91.16689.3.91.1672
10789.3.91.168/3089.3.91.169 to 89.3.91.17089.3.91.1712
10889.3.91.172/3089.3.91.173 to 89.3.91.17489.3.91.1752
10989.3.91.176/3089.3.91.177 to 89.3.91.17889.3.91.1792
11089.3.91.180/3089.3.91.181 to 89.3.91.18289.3.91.1832
11189.3.91.184/3089.3.91.185 to 89.3.91.18689.3.91.1872
11289.3.91.188/3089.3.91.189 to 89.3.91.19089.3.91.1912
11389.3.91.192/3089.3.91.193 to 89.3.91.19489.3.91.1952
11489.3.91.196/3089.3.91.197 to 89.3.91.19889.3.91.1992
11589.3.91.200/3089.3.91.201 to 89.3.91.20289.3.91.2032
11689.3.91.204/3089.3.91.205 to 89.3.91.20689.3.91.2072
11789.3.91.208/3089.3.91.209 to 89.3.91.21089.3.91.2112
11889.3.91.212/3089.3.91.213 to 89.3.91.21489.3.91.2152
11989.3.91.216/3089.3.91.217 to 89.3.91.21889.3.91.2192
12089.3.91.220/3089.3.91.221 to 89.3.91.22289.3.91.2232
12189.3.91.224/3089.3.91.225 to 89.3.91.22689.3.91.2272
12289.3.91.228/3089.3.91.229 to 89.3.91.23089.3.91.2312
12389.3.91.232/3089.3.91.233 to 89.3.91.23489.3.91.2352
12489.3.91.236/3089.3.91.237 to 89.3.91.23889.3.91.2392
12589.3.91.240/3089.3.91.241 to 89.3.91.24289.3.91.2432
12689.3.91.244/3089.3.91.245 to 89.3.91.24689.3.91.2472
12789.3.91.248/3089.3.91.249 to 89.3.91.25089.3.91.2512
12889.3.91.252/3089.3.91.253 to 89.3.91.25489.3.91.2552

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