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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.

Network5.167.2.0/23
Usable hosts510
Subnet mask255.255.254.0
Addresses512
Network address
5.167.2.0
Broadcast address
5.167.3.255
First usable
5.167.2.1
Last usable
5.167.3.254
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 05A70200 · Integer 94831104 to 94831615
Reverse DNS zones
2.167.5.in-addr.arpa
3.167.5.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
Address00000101.10100111.00000010.000000005.167.2.0
Subnet mask11111111.11111111.11111110.00000000255.255.254.0
Network00000101.10100111.00000010.000000005.167.2.0
Broadcast00000101.10100111.00000011.111111115.167.3.255
Split into smaller subnets/30

5.167.2.0/23 makes 128 subnets of /30.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
15.167.2.0/305.167.2.1 to 5.167.2.25.167.2.32
25.167.2.4/305.167.2.5 to 5.167.2.65.167.2.72
35.167.2.8/305.167.2.9 to 5.167.2.105.167.2.112
45.167.2.12/305.167.2.13 to 5.167.2.145.167.2.152
55.167.2.16/305.167.2.17 to 5.167.2.185.167.2.192
65.167.2.20/305.167.2.21 to 5.167.2.225.167.2.232
75.167.2.24/305.167.2.25 to 5.167.2.265.167.2.272
85.167.2.28/305.167.2.29 to 5.167.2.305.167.2.312
95.167.2.32/305.167.2.33 to 5.167.2.345.167.2.352
105.167.2.36/305.167.2.37 to 5.167.2.385.167.2.392
115.167.2.40/305.167.2.41 to 5.167.2.425.167.2.432
125.167.2.44/305.167.2.45 to 5.167.2.465.167.2.472
135.167.2.48/305.167.2.49 to 5.167.2.505.167.2.512
145.167.2.52/305.167.2.53 to 5.167.2.545.167.2.552
155.167.2.56/305.167.2.57 to 5.167.2.585.167.2.592
165.167.2.60/305.167.2.61 to 5.167.2.625.167.2.632
175.167.2.64/305.167.2.65 to 5.167.2.665.167.2.672
185.167.2.68/305.167.2.69 to 5.167.2.705.167.2.712
195.167.2.72/305.167.2.73 to 5.167.2.745.167.2.752
205.167.2.76/305.167.2.77 to 5.167.2.785.167.2.792
215.167.2.80/305.167.2.81 to 5.167.2.825.167.2.832
225.167.2.84/305.167.2.85 to 5.167.2.865.167.2.872
235.167.2.88/305.167.2.89 to 5.167.2.905.167.2.912
245.167.2.92/305.167.2.93 to 5.167.2.945.167.2.952
255.167.2.96/305.167.2.97 to 5.167.2.985.167.2.992
265.167.2.100/305.167.2.101 to 5.167.2.1025.167.2.1032
275.167.2.104/305.167.2.105 to 5.167.2.1065.167.2.1072
285.167.2.108/305.167.2.109 to 5.167.2.1105.167.2.1112
295.167.2.112/305.167.2.113 to 5.167.2.1145.167.2.1152
305.167.2.116/305.167.2.117 to 5.167.2.1185.167.2.1192
315.167.2.120/305.167.2.121 to 5.167.2.1225.167.2.1232
325.167.2.124/305.167.2.125 to 5.167.2.1265.167.2.1272
335.167.2.128/305.167.2.129 to 5.167.2.1305.167.2.1312
345.167.2.132/305.167.2.133 to 5.167.2.1345.167.2.1352
355.167.2.136/305.167.2.137 to 5.167.2.1385.167.2.1392
365.167.2.140/305.167.2.141 to 5.167.2.1425.167.2.1432
375.167.2.144/305.167.2.145 to 5.167.2.1465.167.2.1472
385.167.2.148/305.167.2.149 to 5.167.2.1505.167.2.1512
395.167.2.152/305.167.2.153 to 5.167.2.1545.167.2.1552
405.167.2.156/305.167.2.157 to 5.167.2.1585.167.2.1592
415.167.2.160/305.167.2.161 to 5.167.2.1625.167.2.1632
425.167.2.164/305.167.2.165 to 5.167.2.1665.167.2.1672
435.167.2.168/305.167.2.169 to 5.167.2.1705.167.2.1712
445.167.2.172/305.167.2.173 to 5.167.2.1745.167.2.1752
455.167.2.176/305.167.2.177 to 5.167.2.1785.167.2.1792
465.167.2.180/305.167.2.181 to 5.167.2.1825.167.2.1832
475.167.2.184/305.167.2.185 to 5.167.2.1865.167.2.1872
485.167.2.188/305.167.2.189 to 5.167.2.1905.167.2.1912
495.167.2.192/305.167.2.193 to 5.167.2.1945.167.2.1952
505.167.2.196/305.167.2.197 to 5.167.2.1985.167.2.1992
515.167.2.200/305.167.2.201 to 5.167.2.2025.167.2.2032
525.167.2.204/305.167.2.205 to 5.167.2.2065.167.2.2072
535.167.2.208/305.167.2.209 to 5.167.2.2105.167.2.2112
545.167.2.212/305.167.2.213 to 5.167.2.2145.167.2.2152
555.167.2.216/305.167.2.217 to 5.167.2.2185.167.2.2192
565.167.2.220/305.167.2.221 to 5.167.2.2225.167.2.2232
575.167.2.224/305.167.2.225 to 5.167.2.2265.167.2.2272
585.167.2.228/305.167.2.229 to 5.167.2.2305.167.2.2312
595.167.2.232/305.167.2.233 to 5.167.2.2345.167.2.2352
605.167.2.236/305.167.2.237 to 5.167.2.2385.167.2.2392
615.167.2.240/305.167.2.241 to 5.167.2.2425.167.2.2432
625.167.2.244/305.167.2.245 to 5.167.2.2465.167.2.2472
635.167.2.248/305.167.2.249 to 5.167.2.2505.167.2.2512
645.167.2.252/305.167.2.253 to 5.167.2.2545.167.2.2552
655.167.3.0/305.167.3.1 to 5.167.3.25.167.3.32
665.167.3.4/305.167.3.5 to 5.167.3.65.167.3.72
675.167.3.8/305.167.3.9 to 5.167.3.105.167.3.112
685.167.3.12/305.167.3.13 to 5.167.3.145.167.3.152
695.167.3.16/305.167.3.17 to 5.167.3.185.167.3.192
705.167.3.20/305.167.3.21 to 5.167.3.225.167.3.232
715.167.3.24/305.167.3.25 to 5.167.3.265.167.3.272
725.167.3.28/305.167.3.29 to 5.167.3.305.167.3.312
735.167.3.32/305.167.3.33 to 5.167.3.345.167.3.352
745.167.3.36/305.167.3.37 to 5.167.3.385.167.3.392
755.167.3.40/305.167.3.41 to 5.167.3.425.167.3.432
765.167.3.44/305.167.3.45 to 5.167.3.465.167.3.472
775.167.3.48/305.167.3.49 to 5.167.3.505.167.3.512
785.167.3.52/305.167.3.53 to 5.167.3.545.167.3.552
795.167.3.56/305.167.3.57 to 5.167.3.585.167.3.592
805.167.3.60/305.167.3.61 to 5.167.3.625.167.3.632
815.167.3.64/305.167.3.65 to 5.167.3.665.167.3.672
825.167.3.68/305.167.3.69 to 5.167.3.705.167.3.712
835.167.3.72/305.167.3.73 to 5.167.3.745.167.3.752
845.167.3.76/305.167.3.77 to 5.167.3.785.167.3.792
855.167.3.80/305.167.3.81 to 5.167.3.825.167.3.832
865.167.3.84/305.167.3.85 to 5.167.3.865.167.3.872
875.167.3.88/305.167.3.89 to 5.167.3.905.167.3.912
885.167.3.92/305.167.3.93 to 5.167.3.945.167.3.952
895.167.3.96/305.167.3.97 to 5.167.3.985.167.3.992
905.167.3.100/305.167.3.101 to 5.167.3.1025.167.3.1032
915.167.3.104/305.167.3.105 to 5.167.3.1065.167.3.1072
925.167.3.108/305.167.3.109 to 5.167.3.1105.167.3.1112
935.167.3.112/305.167.3.113 to 5.167.3.1145.167.3.1152
945.167.3.116/305.167.3.117 to 5.167.3.1185.167.3.1192
955.167.3.120/305.167.3.121 to 5.167.3.1225.167.3.1232
965.167.3.124/305.167.3.125 to 5.167.3.1265.167.3.1272
975.167.3.128/305.167.3.129 to 5.167.3.1305.167.3.1312
985.167.3.132/305.167.3.133 to 5.167.3.1345.167.3.1352
995.167.3.136/305.167.3.137 to 5.167.3.1385.167.3.1392
1005.167.3.140/305.167.3.141 to 5.167.3.1425.167.3.1432
1015.167.3.144/305.167.3.145 to 5.167.3.1465.167.3.1472
1025.167.3.148/305.167.3.149 to 5.167.3.1505.167.3.1512
1035.167.3.152/305.167.3.153 to 5.167.3.1545.167.3.1552
1045.167.3.156/305.167.3.157 to 5.167.3.1585.167.3.1592
1055.167.3.160/305.167.3.161 to 5.167.3.1625.167.3.1632
1065.167.3.164/305.167.3.165 to 5.167.3.1665.167.3.1672
1075.167.3.168/305.167.3.169 to 5.167.3.1705.167.3.1712
1085.167.3.172/305.167.3.173 to 5.167.3.1745.167.3.1752
1095.167.3.176/305.167.3.177 to 5.167.3.1785.167.3.1792
1105.167.3.180/305.167.3.181 to 5.167.3.1825.167.3.1832
1115.167.3.184/305.167.3.185 to 5.167.3.1865.167.3.1872
1125.167.3.188/305.167.3.189 to 5.167.3.1905.167.3.1912
1135.167.3.192/305.167.3.193 to 5.167.3.1945.167.3.1952
1145.167.3.196/305.167.3.197 to 5.167.3.1985.167.3.1992
1155.167.3.200/305.167.3.201 to 5.167.3.2025.167.3.2032
1165.167.3.204/305.167.3.205 to 5.167.3.2065.167.3.2072
1175.167.3.208/305.167.3.209 to 5.167.3.2105.167.3.2112
1185.167.3.212/305.167.3.213 to 5.167.3.2145.167.3.2152
1195.167.3.216/305.167.3.217 to 5.167.3.2185.167.3.2192
1205.167.3.220/305.167.3.221 to 5.167.3.2225.167.3.2232
1215.167.3.224/305.167.3.225 to 5.167.3.2265.167.3.2272
1225.167.3.228/305.167.3.229 to 5.167.3.2305.167.3.2312
1235.167.3.232/305.167.3.233 to 5.167.3.2345.167.3.2352
1245.167.3.236/305.167.3.237 to 5.167.3.2385.167.3.2392
1255.167.3.240/305.167.3.241 to 5.167.3.2425.167.3.2432
1265.167.3.244/305.167.3.245 to 5.167.3.2465.167.3.2472
1275.167.3.248/305.167.3.249 to 5.167.3.2505.167.3.2512
1285.167.3.252/305.167.3.253 to 5.167.3.2545.167.3.2552

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