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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.

Network83.3.210.0/23
Usable hosts510
Subnet mask255.255.254.0
Addresses512
Network address
83.3.210.0
Broadcast address
83.3.211.255
First usable
83.3.210.1
Last usable
83.3.211.254
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 5303D200 · Integer 1392759296 to 1392759807
Reverse DNS zones
210.3.83.in-addr.arpa
211.3.83.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
Address01010011.00000011.11010010.0000000083.3.210.0
Subnet mask11111111.11111111.11111110.00000000255.255.254.0
Network01010011.00000011.11010010.0000000083.3.210.0
Broadcast01010011.00000011.11010011.1111111183.3.211.255
Split into smaller subnets/30

83.3.210.0/23 makes 128 subnets of /30.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
183.3.210.0/3083.3.210.1 to 83.3.210.283.3.210.32
283.3.210.4/3083.3.210.5 to 83.3.210.683.3.210.72
383.3.210.8/3083.3.210.9 to 83.3.210.1083.3.210.112
483.3.210.12/3083.3.210.13 to 83.3.210.1483.3.210.152
583.3.210.16/3083.3.210.17 to 83.3.210.1883.3.210.192
683.3.210.20/3083.3.210.21 to 83.3.210.2283.3.210.232
783.3.210.24/3083.3.210.25 to 83.3.210.2683.3.210.272
883.3.210.28/3083.3.210.29 to 83.3.210.3083.3.210.312
983.3.210.32/3083.3.210.33 to 83.3.210.3483.3.210.352
1083.3.210.36/3083.3.210.37 to 83.3.210.3883.3.210.392
1183.3.210.40/3083.3.210.41 to 83.3.210.4283.3.210.432
1283.3.210.44/3083.3.210.45 to 83.3.210.4683.3.210.472
1383.3.210.48/3083.3.210.49 to 83.3.210.5083.3.210.512
1483.3.210.52/3083.3.210.53 to 83.3.210.5483.3.210.552
1583.3.210.56/3083.3.210.57 to 83.3.210.5883.3.210.592
1683.3.210.60/3083.3.210.61 to 83.3.210.6283.3.210.632
1783.3.210.64/3083.3.210.65 to 83.3.210.6683.3.210.672
1883.3.210.68/3083.3.210.69 to 83.3.210.7083.3.210.712
1983.3.210.72/3083.3.210.73 to 83.3.210.7483.3.210.752
2083.3.210.76/3083.3.210.77 to 83.3.210.7883.3.210.792
2183.3.210.80/3083.3.210.81 to 83.3.210.8283.3.210.832
2283.3.210.84/3083.3.210.85 to 83.3.210.8683.3.210.872
2383.3.210.88/3083.3.210.89 to 83.3.210.9083.3.210.912
2483.3.210.92/3083.3.210.93 to 83.3.210.9483.3.210.952
2583.3.210.96/3083.3.210.97 to 83.3.210.9883.3.210.992
2683.3.210.100/3083.3.210.101 to 83.3.210.10283.3.210.1032
2783.3.210.104/3083.3.210.105 to 83.3.210.10683.3.210.1072
2883.3.210.108/3083.3.210.109 to 83.3.210.11083.3.210.1112
2983.3.210.112/3083.3.210.113 to 83.3.210.11483.3.210.1152
3083.3.210.116/3083.3.210.117 to 83.3.210.11883.3.210.1192
3183.3.210.120/3083.3.210.121 to 83.3.210.12283.3.210.1232
3283.3.210.124/3083.3.210.125 to 83.3.210.12683.3.210.1272
3383.3.210.128/3083.3.210.129 to 83.3.210.13083.3.210.1312
3483.3.210.132/3083.3.210.133 to 83.3.210.13483.3.210.1352
3583.3.210.136/3083.3.210.137 to 83.3.210.13883.3.210.1392
3683.3.210.140/3083.3.210.141 to 83.3.210.14283.3.210.1432
3783.3.210.144/3083.3.210.145 to 83.3.210.14683.3.210.1472
3883.3.210.148/3083.3.210.149 to 83.3.210.15083.3.210.1512
3983.3.210.152/3083.3.210.153 to 83.3.210.15483.3.210.1552
4083.3.210.156/3083.3.210.157 to 83.3.210.15883.3.210.1592
4183.3.210.160/3083.3.210.161 to 83.3.210.16283.3.210.1632
4283.3.210.164/3083.3.210.165 to 83.3.210.16683.3.210.1672
4383.3.210.168/3083.3.210.169 to 83.3.210.17083.3.210.1712
4483.3.210.172/3083.3.210.173 to 83.3.210.17483.3.210.1752
4583.3.210.176/3083.3.210.177 to 83.3.210.17883.3.210.1792
4683.3.210.180/3083.3.210.181 to 83.3.210.18283.3.210.1832
4783.3.210.184/3083.3.210.185 to 83.3.210.18683.3.210.1872
4883.3.210.188/3083.3.210.189 to 83.3.210.19083.3.210.1912
4983.3.210.192/3083.3.210.193 to 83.3.210.19483.3.210.1952
5083.3.210.196/3083.3.210.197 to 83.3.210.19883.3.210.1992
5183.3.210.200/3083.3.210.201 to 83.3.210.20283.3.210.2032
5283.3.210.204/3083.3.210.205 to 83.3.210.20683.3.210.2072
5383.3.210.208/3083.3.210.209 to 83.3.210.21083.3.210.2112
5483.3.210.212/3083.3.210.213 to 83.3.210.21483.3.210.2152
5583.3.210.216/3083.3.210.217 to 83.3.210.21883.3.210.2192
5683.3.210.220/3083.3.210.221 to 83.3.210.22283.3.210.2232
5783.3.210.224/3083.3.210.225 to 83.3.210.22683.3.210.2272
5883.3.210.228/3083.3.210.229 to 83.3.210.23083.3.210.2312
5983.3.210.232/3083.3.210.233 to 83.3.210.23483.3.210.2352
6083.3.210.236/3083.3.210.237 to 83.3.210.23883.3.210.2392
6183.3.210.240/3083.3.210.241 to 83.3.210.24283.3.210.2432
6283.3.210.244/3083.3.210.245 to 83.3.210.24683.3.210.2472
6383.3.210.248/3083.3.210.249 to 83.3.210.25083.3.210.2512
6483.3.210.252/3083.3.210.253 to 83.3.210.25483.3.210.2552
6583.3.211.0/3083.3.211.1 to 83.3.211.283.3.211.32
6683.3.211.4/3083.3.211.5 to 83.3.211.683.3.211.72
6783.3.211.8/3083.3.211.9 to 83.3.211.1083.3.211.112
6883.3.211.12/3083.3.211.13 to 83.3.211.1483.3.211.152
6983.3.211.16/3083.3.211.17 to 83.3.211.1883.3.211.192
7083.3.211.20/3083.3.211.21 to 83.3.211.2283.3.211.232
7183.3.211.24/3083.3.211.25 to 83.3.211.2683.3.211.272
7283.3.211.28/3083.3.211.29 to 83.3.211.3083.3.211.312
7383.3.211.32/3083.3.211.33 to 83.3.211.3483.3.211.352
7483.3.211.36/3083.3.211.37 to 83.3.211.3883.3.211.392
7583.3.211.40/3083.3.211.41 to 83.3.211.4283.3.211.432
7683.3.211.44/3083.3.211.45 to 83.3.211.4683.3.211.472
7783.3.211.48/3083.3.211.49 to 83.3.211.5083.3.211.512
7883.3.211.52/3083.3.211.53 to 83.3.211.5483.3.211.552
7983.3.211.56/3083.3.211.57 to 83.3.211.5883.3.211.592
8083.3.211.60/3083.3.211.61 to 83.3.211.6283.3.211.632
8183.3.211.64/3083.3.211.65 to 83.3.211.6683.3.211.672
8283.3.211.68/3083.3.211.69 to 83.3.211.7083.3.211.712
8383.3.211.72/3083.3.211.73 to 83.3.211.7483.3.211.752
8483.3.211.76/3083.3.211.77 to 83.3.211.7883.3.211.792
8583.3.211.80/3083.3.211.81 to 83.3.211.8283.3.211.832
8683.3.211.84/3083.3.211.85 to 83.3.211.8683.3.211.872
8783.3.211.88/3083.3.211.89 to 83.3.211.9083.3.211.912
8883.3.211.92/3083.3.211.93 to 83.3.211.9483.3.211.952
8983.3.211.96/3083.3.211.97 to 83.3.211.9883.3.211.992
9083.3.211.100/3083.3.211.101 to 83.3.211.10283.3.211.1032
9183.3.211.104/3083.3.211.105 to 83.3.211.10683.3.211.1072
9283.3.211.108/3083.3.211.109 to 83.3.211.11083.3.211.1112
9383.3.211.112/3083.3.211.113 to 83.3.211.11483.3.211.1152
9483.3.211.116/3083.3.211.117 to 83.3.211.11883.3.211.1192
9583.3.211.120/3083.3.211.121 to 83.3.211.12283.3.211.1232
9683.3.211.124/3083.3.211.125 to 83.3.211.12683.3.211.1272
9783.3.211.128/3083.3.211.129 to 83.3.211.13083.3.211.1312
9883.3.211.132/3083.3.211.133 to 83.3.211.13483.3.211.1352
9983.3.211.136/3083.3.211.137 to 83.3.211.13883.3.211.1392
10083.3.211.140/3083.3.211.141 to 83.3.211.14283.3.211.1432
10183.3.211.144/3083.3.211.145 to 83.3.211.14683.3.211.1472
10283.3.211.148/3083.3.211.149 to 83.3.211.15083.3.211.1512
10383.3.211.152/3083.3.211.153 to 83.3.211.15483.3.211.1552
10483.3.211.156/3083.3.211.157 to 83.3.211.15883.3.211.1592
10583.3.211.160/3083.3.211.161 to 83.3.211.16283.3.211.1632
10683.3.211.164/3083.3.211.165 to 83.3.211.16683.3.211.1672
10783.3.211.168/3083.3.211.169 to 83.3.211.17083.3.211.1712
10883.3.211.172/3083.3.211.173 to 83.3.211.17483.3.211.1752
10983.3.211.176/3083.3.211.177 to 83.3.211.17883.3.211.1792
11083.3.211.180/3083.3.211.181 to 83.3.211.18283.3.211.1832
11183.3.211.184/3083.3.211.185 to 83.3.211.18683.3.211.1872
11283.3.211.188/3083.3.211.189 to 83.3.211.19083.3.211.1912
11383.3.211.192/3083.3.211.193 to 83.3.211.19483.3.211.1952
11483.3.211.196/3083.3.211.197 to 83.3.211.19883.3.211.1992
11583.3.211.200/3083.3.211.201 to 83.3.211.20283.3.211.2032
11683.3.211.204/3083.3.211.205 to 83.3.211.20683.3.211.2072
11783.3.211.208/3083.3.211.209 to 83.3.211.21083.3.211.2112
11883.3.211.212/3083.3.211.213 to 83.3.211.21483.3.211.2152
11983.3.211.216/3083.3.211.217 to 83.3.211.21883.3.211.2192
12083.3.211.220/3083.3.211.221 to 83.3.211.22283.3.211.2232
12183.3.211.224/3083.3.211.225 to 83.3.211.22683.3.211.2272
12283.3.211.228/3083.3.211.229 to 83.3.211.23083.3.211.2312
12383.3.211.232/3083.3.211.233 to 83.3.211.23483.3.211.2352
12483.3.211.236/3083.3.211.237 to 83.3.211.23883.3.211.2392
12583.3.211.240/3083.3.211.241 to 83.3.211.24283.3.211.2432
12683.3.211.244/3083.3.211.245 to 83.3.211.24683.3.211.2472
12783.3.211.248/3083.3.211.249 to 83.3.211.25083.3.211.2512
12883.3.211.252/3083.3.211.253 to 83.3.211.25483.3.211.2552

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