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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.

Network85.167.2.0/23
Usable hosts510
Subnet mask255.255.254.0
Addresses512
Network address
85.167.2.0
Broadcast address
85.167.3.255
First usable
85.167.2.1
Last usable
85.167.3.254
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 55A70200 · Integer 1437008384 to 1437008895
Reverse DNS zones
2.167.85.in-addr.arpa
3.167.85.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
Address01010101.10100111.00000010.0000000085.167.2.0
Subnet mask11111111.11111111.11111110.00000000255.255.254.0
Network01010101.10100111.00000010.0000000085.167.2.0
Broadcast01010101.10100111.00000011.1111111185.167.3.255
Split into smaller subnets/30

85.167.2.0/23 makes 128 subnets of /30.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
185.167.2.0/3085.167.2.1 to 85.167.2.285.167.2.32
285.167.2.4/3085.167.2.5 to 85.167.2.685.167.2.72
385.167.2.8/3085.167.2.9 to 85.167.2.1085.167.2.112
485.167.2.12/3085.167.2.13 to 85.167.2.1485.167.2.152
585.167.2.16/3085.167.2.17 to 85.167.2.1885.167.2.192
685.167.2.20/3085.167.2.21 to 85.167.2.2285.167.2.232
785.167.2.24/3085.167.2.25 to 85.167.2.2685.167.2.272
885.167.2.28/3085.167.2.29 to 85.167.2.3085.167.2.312
985.167.2.32/3085.167.2.33 to 85.167.2.3485.167.2.352
1085.167.2.36/3085.167.2.37 to 85.167.2.3885.167.2.392
1185.167.2.40/3085.167.2.41 to 85.167.2.4285.167.2.432
1285.167.2.44/3085.167.2.45 to 85.167.2.4685.167.2.472
1385.167.2.48/3085.167.2.49 to 85.167.2.5085.167.2.512
1485.167.2.52/3085.167.2.53 to 85.167.2.5485.167.2.552
1585.167.2.56/3085.167.2.57 to 85.167.2.5885.167.2.592
1685.167.2.60/3085.167.2.61 to 85.167.2.6285.167.2.632
1785.167.2.64/3085.167.2.65 to 85.167.2.6685.167.2.672
1885.167.2.68/3085.167.2.69 to 85.167.2.7085.167.2.712
1985.167.2.72/3085.167.2.73 to 85.167.2.7485.167.2.752
2085.167.2.76/3085.167.2.77 to 85.167.2.7885.167.2.792
2185.167.2.80/3085.167.2.81 to 85.167.2.8285.167.2.832
2285.167.2.84/3085.167.2.85 to 85.167.2.8685.167.2.872
2385.167.2.88/3085.167.2.89 to 85.167.2.9085.167.2.912
2485.167.2.92/3085.167.2.93 to 85.167.2.9485.167.2.952
2585.167.2.96/3085.167.2.97 to 85.167.2.9885.167.2.992
2685.167.2.100/3085.167.2.101 to 85.167.2.10285.167.2.1032
2785.167.2.104/3085.167.2.105 to 85.167.2.10685.167.2.1072
2885.167.2.108/3085.167.2.109 to 85.167.2.11085.167.2.1112
2985.167.2.112/3085.167.2.113 to 85.167.2.11485.167.2.1152
3085.167.2.116/3085.167.2.117 to 85.167.2.11885.167.2.1192
3185.167.2.120/3085.167.2.121 to 85.167.2.12285.167.2.1232
3285.167.2.124/3085.167.2.125 to 85.167.2.12685.167.2.1272
3385.167.2.128/3085.167.2.129 to 85.167.2.13085.167.2.1312
3485.167.2.132/3085.167.2.133 to 85.167.2.13485.167.2.1352
3585.167.2.136/3085.167.2.137 to 85.167.2.13885.167.2.1392
3685.167.2.140/3085.167.2.141 to 85.167.2.14285.167.2.1432
3785.167.2.144/3085.167.2.145 to 85.167.2.14685.167.2.1472
3885.167.2.148/3085.167.2.149 to 85.167.2.15085.167.2.1512
3985.167.2.152/3085.167.2.153 to 85.167.2.15485.167.2.1552
4085.167.2.156/3085.167.2.157 to 85.167.2.15885.167.2.1592
4185.167.2.160/3085.167.2.161 to 85.167.2.16285.167.2.1632
4285.167.2.164/3085.167.2.165 to 85.167.2.16685.167.2.1672
4385.167.2.168/3085.167.2.169 to 85.167.2.17085.167.2.1712
4485.167.2.172/3085.167.2.173 to 85.167.2.17485.167.2.1752
4585.167.2.176/3085.167.2.177 to 85.167.2.17885.167.2.1792
4685.167.2.180/3085.167.2.181 to 85.167.2.18285.167.2.1832
4785.167.2.184/3085.167.2.185 to 85.167.2.18685.167.2.1872
4885.167.2.188/3085.167.2.189 to 85.167.2.19085.167.2.1912
4985.167.2.192/3085.167.2.193 to 85.167.2.19485.167.2.1952
5085.167.2.196/3085.167.2.197 to 85.167.2.19885.167.2.1992
5185.167.2.200/3085.167.2.201 to 85.167.2.20285.167.2.2032
5285.167.2.204/3085.167.2.205 to 85.167.2.20685.167.2.2072
5385.167.2.208/3085.167.2.209 to 85.167.2.21085.167.2.2112
5485.167.2.212/3085.167.2.213 to 85.167.2.21485.167.2.2152
5585.167.2.216/3085.167.2.217 to 85.167.2.21885.167.2.2192
5685.167.2.220/3085.167.2.221 to 85.167.2.22285.167.2.2232
5785.167.2.224/3085.167.2.225 to 85.167.2.22685.167.2.2272
5885.167.2.228/3085.167.2.229 to 85.167.2.23085.167.2.2312
5985.167.2.232/3085.167.2.233 to 85.167.2.23485.167.2.2352
6085.167.2.236/3085.167.2.237 to 85.167.2.23885.167.2.2392
6185.167.2.240/3085.167.2.241 to 85.167.2.24285.167.2.2432
6285.167.2.244/3085.167.2.245 to 85.167.2.24685.167.2.2472
6385.167.2.248/3085.167.2.249 to 85.167.2.25085.167.2.2512
6485.167.2.252/3085.167.2.253 to 85.167.2.25485.167.2.2552
6585.167.3.0/3085.167.3.1 to 85.167.3.285.167.3.32
6685.167.3.4/3085.167.3.5 to 85.167.3.685.167.3.72
6785.167.3.8/3085.167.3.9 to 85.167.3.1085.167.3.112
6885.167.3.12/3085.167.3.13 to 85.167.3.1485.167.3.152
6985.167.3.16/3085.167.3.17 to 85.167.3.1885.167.3.192
7085.167.3.20/3085.167.3.21 to 85.167.3.2285.167.3.232
7185.167.3.24/3085.167.3.25 to 85.167.3.2685.167.3.272
7285.167.3.28/3085.167.3.29 to 85.167.3.3085.167.3.312
7385.167.3.32/3085.167.3.33 to 85.167.3.3485.167.3.352
7485.167.3.36/3085.167.3.37 to 85.167.3.3885.167.3.392
7585.167.3.40/3085.167.3.41 to 85.167.3.4285.167.3.432
7685.167.3.44/3085.167.3.45 to 85.167.3.4685.167.3.472
7785.167.3.48/3085.167.3.49 to 85.167.3.5085.167.3.512
7885.167.3.52/3085.167.3.53 to 85.167.3.5485.167.3.552
7985.167.3.56/3085.167.3.57 to 85.167.3.5885.167.3.592
8085.167.3.60/3085.167.3.61 to 85.167.3.6285.167.3.632
8185.167.3.64/3085.167.3.65 to 85.167.3.6685.167.3.672
8285.167.3.68/3085.167.3.69 to 85.167.3.7085.167.3.712
8385.167.3.72/3085.167.3.73 to 85.167.3.7485.167.3.752
8485.167.3.76/3085.167.3.77 to 85.167.3.7885.167.3.792
8585.167.3.80/3085.167.3.81 to 85.167.3.8285.167.3.832
8685.167.3.84/3085.167.3.85 to 85.167.3.8685.167.3.872
8785.167.3.88/3085.167.3.89 to 85.167.3.9085.167.3.912
8885.167.3.92/3085.167.3.93 to 85.167.3.9485.167.3.952
8985.167.3.96/3085.167.3.97 to 85.167.3.9885.167.3.992
9085.167.3.100/3085.167.3.101 to 85.167.3.10285.167.3.1032
9185.167.3.104/3085.167.3.105 to 85.167.3.10685.167.3.1072
9285.167.3.108/3085.167.3.109 to 85.167.3.11085.167.3.1112
9385.167.3.112/3085.167.3.113 to 85.167.3.11485.167.3.1152
9485.167.3.116/3085.167.3.117 to 85.167.3.11885.167.3.1192
9585.167.3.120/3085.167.3.121 to 85.167.3.12285.167.3.1232
9685.167.3.124/3085.167.3.125 to 85.167.3.12685.167.3.1272
9785.167.3.128/3085.167.3.129 to 85.167.3.13085.167.3.1312
9885.167.3.132/3085.167.3.133 to 85.167.3.13485.167.3.1352
9985.167.3.136/3085.167.3.137 to 85.167.3.13885.167.3.1392
10085.167.3.140/3085.167.3.141 to 85.167.3.14285.167.3.1432
10185.167.3.144/3085.167.3.145 to 85.167.3.14685.167.3.1472
10285.167.3.148/3085.167.3.149 to 85.167.3.15085.167.3.1512
10385.167.3.152/3085.167.3.153 to 85.167.3.15485.167.3.1552
10485.167.3.156/3085.167.3.157 to 85.167.3.15885.167.3.1592
10585.167.3.160/3085.167.3.161 to 85.167.3.16285.167.3.1632
10685.167.3.164/3085.167.3.165 to 85.167.3.16685.167.3.1672
10785.167.3.168/3085.167.3.169 to 85.167.3.17085.167.3.1712
10885.167.3.172/3085.167.3.173 to 85.167.3.17485.167.3.1752
10985.167.3.176/3085.167.3.177 to 85.167.3.17885.167.3.1792
11085.167.3.180/3085.167.3.181 to 85.167.3.18285.167.3.1832
11185.167.3.184/3085.167.3.185 to 85.167.3.18685.167.3.1872
11285.167.3.188/3085.167.3.189 to 85.167.3.19085.167.3.1912
11385.167.3.192/3085.167.3.193 to 85.167.3.19485.167.3.1952
11485.167.3.196/3085.167.3.197 to 85.167.3.19885.167.3.1992
11585.167.3.200/3085.167.3.201 to 85.167.3.20285.167.3.2032
11685.167.3.204/3085.167.3.205 to 85.167.3.20685.167.3.2072
11785.167.3.208/3085.167.3.209 to 85.167.3.21085.167.3.2112
11885.167.3.212/3085.167.3.213 to 85.167.3.21485.167.3.2152
11985.167.3.216/3085.167.3.217 to 85.167.3.21885.167.3.2192
12085.167.3.220/3085.167.3.221 to 85.167.3.22285.167.3.2232
12185.167.3.224/3085.167.3.225 to 85.167.3.22685.167.3.2272
12285.167.3.228/3085.167.3.229 to 85.167.3.23085.167.3.2312
12385.167.3.232/3085.167.3.233 to 85.167.3.23485.167.3.2352
12485.167.3.236/3085.167.3.237 to 85.167.3.23885.167.3.2392
12585.167.3.240/3085.167.3.241 to 85.167.3.24285.167.3.2432
12685.167.3.244/3085.167.3.245 to 85.167.3.24685.167.3.2472
12785.167.3.248/3085.167.3.249 to 85.167.3.25085.167.3.2512
12885.167.3.252/3085.167.3.253 to 85.167.3.25485.167.3.2552

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