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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.

Network105.76.0.0/16
Usable hosts65,534
Subnet mask255.255.0.0
Addresses65,536
Network address
105.76.0.0
Broadcast address
105.76.255.255
First usable
105.76.0.1
Last usable
105.76.255.254
Usable hosts
65,534 (65,536 less the network and broadcast addresses)
Subnet mask
255.255.0.0
Wildcard mask
0.0.255.255 (Cisco ACLs, OSPF)
Prefix length
/16
Type
Public public
Old class
A (default /8)
As numbers
Hex 694C0000 · Integer 1766588416 to 1766653951
Reverse DNS zone
76.105.in-addr.arpa
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address01101001.01001100..00000000.00000000105.76.0.0
Subnet mask11111111.11111111..00000000.00000000255.255.0.0
Network01101001.01001100..00000000.00000000105.76.0.0
Broadcast01101001.01001100..11111111.11111111105.76.255.255
Split into smaller subnets/23

105.76.0.0/16 makes 128 subnets of /23.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
1105.76.0.0/23105.76.0.1 to 105.76.1.254105.76.1.255510
2105.76.2.0/23105.76.2.1 to 105.76.3.254105.76.3.255510
3105.76.4.0/23105.76.4.1 to 105.76.5.254105.76.5.255510
4105.76.6.0/23105.76.6.1 to 105.76.7.254105.76.7.255510
5105.76.8.0/23105.76.8.1 to 105.76.9.254105.76.9.255510
6105.76.10.0/23105.76.10.1 to 105.76.11.254105.76.11.255510
7105.76.12.0/23105.76.12.1 to 105.76.13.254105.76.13.255510
8105.76.14.0/23105.76.14.1 to 105.76.15.254105.76.15.255510
9105.76.16.0/23105.76.16.1 to 105.76.17.254105.76.17.255510
10105.76.18.0/23105.76.18.1 to 105.76.19.254105.76.19.255510
11105.76.20.0/23105.76.20.1 to 105.76.21.254105.76.21.255510
12105.76.22.0/23105.76.22.1 to 105.76.23.254105.76.23.255510
13105.76.24.0/23105.76.24.1 to 105.76.25.254105.76.25.255510
14105.76.26.0/23105.76.26.1 to 105.76.27.254105.76.27.255510
15105.76.28.0/23105.76.28.1 to 105.76.29.254105.76.29.255510
16105.76.30.0/23105.76.30.1 to 105.76.31.254105.76.31.255510
17105.76.32.0/23105.76.32.1 to 105.76.33.254105.76.33.255510
18105.76.34.0/23105.76.34.1 to 105.76.35.254105.76.35.255510
19105.76.36.0/23105.76.36.1 to 105.76.37.254105.76.37.255510
20105.76.38.0/23105.76.38.1 to 105.76.39.254105.76.39.255510
21105.76.40.0/23105.76.40.1 to 105.76.41.254105.76.41.255510
22105.76.42.0/23105.76.42.1 to 105.76.43.254105.76.43.255510
23105.76.44.0/23105.76.44.1 to 105.76.45.254105.76.45.255510
24105.76.46.0/23105.76.46.1 to 105.76.47.254105.76.47.255510
25105.76.48.0/23105.76.48.1 to 105.76.49.254105.76.49.255510
26105.76.50.0/23105.76.50.1 to 105.76.51.254105.76.51.255510
27105.76.52.0/23105.76.52.1 to 105.76.53.254105.76.53.255510
28105.76.54.0/23105.76.54.1 to 105.76.55.254105.76.55.255510
29105.76.56.0/23105.76.56.1 to 105.76.57.254105.76.57.255510
30105.76.58.0/23105.76.58.1 to 105.76.59.254105.76.59.255510
31105.76.60.0/23105.76.60.1 to 105.76.61.254105.76.61.255510
32105.76.62.0/23105.76.62.1 to 105.76.63.254105.76.63.255510
33105.76.64.0/23105.76.64.1 to 105.76.65.254105.76.65.255510
34105.76.66.0/23105.76.66.1 to 105.76.67.254105.76.67.255510
35105.76.68.0/23105.76.68.1 to 105.76.69.254105.76.69.255510
36105.76.70.0/23105.76.70.1 to 105.76.71.254105.76.71.255510
37105.76.72.0/23105.76.72.1 to 105.76.73.254105.76.73.255510
38105.76.74.0/23105.76.74.1 to 105.76.75.254105.76.75.255510
39105.76.76.0/23105.76.76.1 to 105.76.77.254105.76.77.255510
40105.76.78.0/23105.76.78.1 to 105.76.79.254105.76.79.255510
41105.76.80.0/23105.76.80.1 to 105.76.81.254105.76.81.255510
42105.76.82.0/23105.76.82.1 to 105.76.83.254105.76.83.255510
43105.76.84.0/23105.76.84.1 to 105.76.85.254105.76.85.255510
44105.76.86.0/23105.76.86.1 to 105.76.87.254105.76.87.255510
45105.76.88.0/23105.76.88.1 to 105.76.89.254105.76.89.255510
46105.76.90.0/23105.76.90.1 to 105.76.91.254105.76.91.255510
47105.76.92.0/23105.76.92.1 to 105.76.93.254105.76.93.255510
48105.76.94.0/23105.76.94.1 to 105.76.95.254105.76.95.255510
49105.76.96.0/23105.76.96.1 to 105.76.97.254105.76.97.255510
50105.76.98.0/23105.76.98.1 to 105.76.99.254105.76.99.255510
51105.76.100.0/23105.76.100.1 to 105.76.101.254105.76.101.255510
52105.76.102.0/23105.76.102.1 to 105.76.103.254105.76.103.255510
53105.76.104.0/23105.76.104.1 to 105.76.105.254105.76.105.255510
54105.76.106.0/23105.76.106.1 to 105.76.107.254105.76.107.255510
55105.76.108.0/23105.76.108.1 to 105.76.109.254105.76.109.255510
56105.76.110.0/23105.76.110.1 to 105.76.111.254105.76.111.255510
57105.76.112.0/23105.76.112.1 to 105.76.113.254105.76.113.255510
58105.76.114.0/23105.76.114.1 to 105.76.115.254105.76.115.255510
59105.76.116.0/23105.76.116.1 to 105.76.117.254105.76.117.255510
60105.76.118.0/23105.76.118.1 to 105.76.119.254105.76.119.255510
61105.76.120.0/23105.76.120.1 to 105.76.121.254105.76.121.255510
62105.76.122.0/23105.76.122.1 to 105.76.123.254105.76.123.255510
63105.76.124.0/23105.76.124.1 to 105.76.125.254105.76.125.255510
64105.76.126.0/23105.76.126.1 to 105.76.127.254105.76.127.255510
65105.76.128.0/23105.76.128.1 to 105.76.129.254105.76.129.255510
66105.76.130.0/23105.76.130.1 to 105.76.131.254105.76.131.255510
67105.76.132.0/23105.76.132.1 to 105.76.133.254105.76.133.255510
68105.76.134.0/23105.76.134.1 to 105.76.135.254105.76.135.255510
69105.76.136.0/23105.76.136.1 to 105.76.137.254105.76.137.255510
70105.76.138.0/23105.76.138.1 to 105.76.139.254105.76.139.255510
71105.76.140.0/23105.76.140.1 to 105.76.141.254105.76.141.255510
72105.76.142.0/23105.76.142.1 to 105.76.143.254105.76.143.255510
73105.76.144.0/23105.76.144.1 to 105.76.145.254105.76.145.255510
74105.76.146.0/23105.76.146.1 to 105.76.147.254105.76.147.255510
75105.76.148.0/23105.76.148.1 to 105.76.149.254105.76.149.255510
76105.76.150.0/23105.76.150.1 to 105.76.151.254105.76.151.255510
77105.76.152.0/23105.76.152.1 to 105.76.153.254105.76.153.255510
78105.76.154.0/23105.76.154.1 to 105.76.155.254105.76.155.255510
79105.76.156.0/23105.76.156.1 to 105.76.157.254105.76.157.255510
80105.76.158.0/23105.76.158.1 to 105.76.159.254105.76.159.255510
81105.76.160.0/23105.76.160.1 to 105.76.161.254105.76.161.255510
82105.76.162.0/23105.76.162.1 to 105.76.163.254105.76.163.255510
83105.76.164.0/23105.76.164.1 to 105.76.165.254105.76.165.255510
84105.76.166.0/23105.76.166.1 to 105.76.167.254105.76.167.255510
85105.76.168.0/23105.76.168.1 to 105.76.169.254105.76.169.255510
86105.76.170.0/23105.76.170.1 to 105.76.171.254105.76.171.255510
87105.76.172.0/23105.76.172.1 to 105.76.173.254105.76.173.255510
88105.76.174.0/23105.76.174.1 to 105.76.175.254105.76.175.255510
89105.76.176.0/23105.76.176.1 to 105.76.177.254105.76.177.255510
90105.76.178.0/23105.76.178.1 to 105.76.179.254105.76.179.255510
91105.76.180.0/23105.76.180.1 to 105.76.181.254105.76.181.255510
92105.76.182.0/23105.76.182.1 to 105.76.183.254105.76.183.255510
93105.76.184.0/23105.76.184.1 to 105.76.185.254105.76.185.255510
94105.76.186.0/23105.76.186.1 to 105.76.187.254105.76.187.255510
95105.76.188.0/23105.76.188.1 to 105.76.189.254105.76.189.255510
96105.76.190.0/23105.76.190.1 to 105.76.191.254105.76.191.255510
97105.76.192.0/23105.76.192.1 to 105.76.193.254105.76.193.255510
98105.76.194.0/23105.76.194.1 to 105.76.195.254105.76.195.255510
99105.76.196.0/23105.76.196.1 to 105.76.197.254105.76.197.255510
100105.76.198.0/23105.76.198.1 to 105.76.199.254105.76.199.255510
101105.76.200.0/23105.76.200.1 to 105.76.201.254105.76.201.255510
102105.76.202.0/23105.76.202.1 to 105.76.203.254105.76.203.255510
103105.76.204.0/23105.76.204.1 to 105.76.205.254105.76.205.255510
104105.76.206.0/23105.76.206.1 to 105.76.207.254105.76.207.255510
105105.76.208.0/23105.76.208.1 to 105.76.209.254105.76.209.255510
106105.76.210.0/23105.76.210.1 to 105.76.211.254105.76.211.255510
107105.76.212.0/23105.76.212.1 to 105.76.213.254105.76.213.255510
108105.76.214.0/23105.76.214.1 to 105.76.215.254105.76.215.255510
109105.76.216.0/23105.76.216.1 to 105.76.217.254105.76.217.255510
110105.76.218.0/23105.76.218.1 to 105.76.219.254105.76.219.255510
111105.76.220.0/23105.76.220.1 to 105.76.221.254105.76.221.255510
112105.76.222.0/23105.76.222.1 to 105.76.223.254105.76.223.255510
113105.76.224.0/23105.76.224.1 to 105.76.225.254105.76.225.255510
114105.76.226.0/23105.76.226.1 to 105.76.227.254105.76.227.255510
115105.76.228.0/23105.76.228.1 to 105.76.229.254105.76.229.255510
116105.76.230.0/23105.76.230.1 to 105.76.231.254105.76.231.255510
117105.76.232.0/23105.76.232.1 to 105.76.233.254105.76.233.255510
118105.76.234.0/23105.76.234.1 to 105.76.235.254105.76.235.255510
119105.76.236.0/23105.76.236.1 to 105.76.237.254105.76.237.255510
120105.76.238.0/23105.76.238.1 to 105.76.239.254105.76.239.255510
121105.76.240.0/23105.76.240.1 to 105.76.241.254105.76.241.255510
122105.76.242.0/23105.76.242.1 to 105.76.243.254105.76.243.255510
123105.76.244.0/23105.76.244.1 to 105.76.245.254105.76.245.255510
124105.76.246.0/23105.76.246.1 to 105.76.247.254105.76.247.255510
125105.76.248.0/23105.76.248.1 to 105.76.249.254105.76.249.255510
126105.76.250.0/23105.76.250.1 to 105.76.251.254105.76.251.255510
127105.76.252.0/23105.76.252.1 to 105.76.253.254105.76.253.255510
128105.76.254.0/23105.76.254.1 to 105.76.255.254105.76.255.255510

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