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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.

Network103.63.0.0/16
Usable hosts65,534
Subnet mask255.255.0.0
Addresses65,536
Network address
103.63.0.0
Broadcast address
103.63.255.255
First usable
103.63.0.1
Last usable
103.63.255.254
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 673F0000 · Integer 1732182016 to 1732247551
Reverse DNS zone
63.103.in-addr.arpa
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address01100111.00111111..00000000.00000000103.63.0.0
Subnet mask11111111.11111111..00000000.00000000255.255.0.0
Network01100111.00111111..00000000.00000000103.63.0.0
Broadcast01100111.00111111..11111111.11111111103.63.255.255
Split into smaller subnets/23

103.63.0.0/16 makes 128 subnets of /23.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
1103.63.0.0/23103.63.0.1 to 103.63.1.254103.63.1.255510
2103.63.2.0/23103.63.2.1 to 103.63.3.254103.63.3.255510
3103.63.4.0/23103.63.4.1 to 103.63.5.254103.63.5.255510
4103.63.6.0/23103.63.6.1 to 103.63.7.254103.63.7.255510
5103.63.8.0/23103.63.8.1 to 103.63.9.254103.63.9.255510
6103.63.10.0/23103.63.10.1 to 103.63.11.254103.63.11.255510
7103.63.12.0/23103.63.12.1 to 103.63.13.254103.63.13.255510
8103.63.14.0/23103.63.14.1 to 103.63.15.254103.63.15.255510
9103.63.16.0/23103.63.16.1 to 103.63.17.254103.63.17.255510
10103.63.18.0/23103.63.18.1 to 103.63.19.254103.63.19.255510
11103.63.20.0/23103.63.20.1 to 103.63.21.254103.63.21.255510
12103.63.22.0/23103.63.22.1 to 103.63.23.254103.63.23.255510
13103.63.24.0/23103.63.24.1 to 103.63.25.254103.63.25.255510
14103.63.26.0/23103.63.26.1 to 103.63.27.254103.63.27.255510
15103.63.28.0/23103.63.28.1 to 103.63.29.254103.63.29.255510
16103.63.30.0/23103.63.30.1 to 103.63.31.254103.63.31.255510
17103.63.32.0/23103.63.32.1 to 103.63.33.254103.63.33.255510
18103.63.34.0/23103.63.34.1 to 103.63.35.254103.63.35.255510
19103.63.36.0/23103.63.36.1 to 103.63.37.254103.63.37.255510
20103.63.38.0/23103.63.38.1 to 103.63.39.254103.63.39.255510
21103.63.40.0/23103.63.40.1 to 103.63.41.254103.63.41.255510
22103.63.42.0/23103.63.42.1 to 103.63.43.254103.63.43.255510
23103.63.44.0/23103.63.44.1 to 103.63.45.254103.63.45.255510
24103.63.46.0/23103.63.46.1 to 103.63.47.254103.63.47.255510
25103.63.48.0/23103.63.48.1 to 103.63.49.254103.63.49.255510
26103.63.50.0/23103.63.50.1 to 103.63.51.254103.63.51.255510
27103.63.52.0/23103.63.52.1 to 103.63.53.254103.63.53.255510
28103.63.54.0/23103.63.54.1 to 103.63.55.254103.63.55.255510
29103.63.56.0/23103.63.56.1 to 103.63.57.254103.63.57.255510
30103.63.58.0/23103.63.58.1 to 103.63.59.254103.63.59.255510
31103.63.60.0/23103.63.60.1 to 103.63.61.254103.63.61.255510
32103.63.62.0/23103.63.62.1 to 103.63.63.254103.63.63.255510
33103.63.64.0/23103.63.64.1 to 103.63.65.254103.63.65.255510
34103.63.66.0/23103.63.66.1 to 103.63.67.254103.63.67.255510
35103.63.68.0/23103.63.68.1 to 103.63.69.254103.63.69.255510
36103.63.70.0/23103.63.70.1 to 103.63.71.254103.63.71.255510
37103.63.72.0/23103.63.72.1 to 103.63.73.254103.63.73.255510
38103.63.74.0/23103.63.74.1 to 103.63.75.254103.63.75.255510
39103.63.76.0/23103.63.76.1 to 103.63.77.254103.63.77.255510
40103.63.78.0/23103.63.78.1 to 103.63.79.254103.63.79.255510
41103.63.80.0/23103.63.80.1 to 103.63.81.254103.63.81.255510
42103.63.82.0/23103.63.82.1 to 103.63.83.254103.63.83.255510
43103.63.84.0/23103.63.84.1 to 103.63.85.254103.63.85.255510
44103.63.86.0/23103.63.86.1 to 103.63.87.254103.63.87.255510
45103.63.88.0/23103.63.88.1 to 103.63.89.254103.63.89.255510
46103.63.90.0/23103.63.90.1 to 103.63.91.254103.63.91.255510
47103.63.92.0/23103.63.92.1 to 103.63.93.254103.63.93.255510
48103.63.94.0/23103.63.94.1 to 103.63.95.254103.63.95.255510
49103.63.96.0/23103.63.96.1 to 103.63.97.254103.63.97.255510
50103.63.98.0/23103.63.98.1 to 103.63.99.254103.63.99.255510
51103.63.100.0/23103.63.100.1 to 103.63.101.254103.63.101.255510
52103.63.102.0/23103.63.102.1 to 103.63.103.254103.63.103.255510
53103.63.104.0/23103.63.104.1 to 103.63.105.254103.63.105.255510
54103.63.106.0/23103.63.106.1 to 103.63.107.254103.63.107.255510
55103.63.108.0/23103.63.108.1 to 103.63.109.254103.63.109.255510
56103.63.110.0/23103.63.110.1 to 103.63.111.254103.63.111.255510
57103.63.112.0/23103.63.112.1 to 103.63.113.254103.63.113.255510
58103.63.114.0/23103.63.114.1 to 103.63.115.254103.63.115.255510
59103.63.116.0/23103.63.116.1 to 103.63.117.254103.63.117.255510
60103.63.118.0/23103.63.118.1 to 103.63.119.254103.63.119.255510
61103.63.120.0/23103.63.120.1 to 103.63.121.254103.63.121.255510
62103.63.122.0/23103.63.122.1 to 103.63.123.254103.63.123.255510
63103.63.124.0/23103.63.124.1 to 103.63.125.254103.63.125.255510
64103.63.126.0/23103.63.126.1 to 103.63.127.254103.63.127.255510
65103.63.128.0/23103.63.128.1 to 103.63.129.254103.63.129.255510
66103.63.130.0/23103.63.130.1 to 103.63.131.254103.63.131.255510
67103.63.132.0/23103.63.132.1 to 103.63.133.254103.63.133.255510
68103.63.134.0/23103.63.134.1 to 103.63.135.254103.63.135.255510
69103.63.136.0/23103.63.136.1 to 103.63.137.254103.63.137.255510
70103.63.138.0/23103.63.138.1 to 103.63.139.254103.63.139.255510
71103.63.140.0/23103.63.140.1 to 103.63.141.254103.63.141.255510
72103.63.142.0/23103.63.142.1 to 103.63.143.254103.63.143.255510
73103.63.144.0/23103.63.144.1 to 103.63.145.254103.63.145.255510
74103.63.146.0/23103.63.146.1 to 103.63.147.254103.63.147.255510
75103.63.148.0/23103.63.148.1 to 103.63.149.254103.63.149.255510
76103.63.150.0/23103.63.150.1 to 103.63.151.254103.63.151.255510
77103.63.152.0/23103.63.152.1 to 103.63.153.254103.63.153.255510
78103.63.154.0/23103.63.154.1 to 103.63.155.254103.63.155.255510
79103.63.156.0/23103.63.156.1 to 103.63.157.254103.63.157.255510
80103.63.158.0/23103.63.158.1 to 103.63.159.254103.63.159.255510
81103.63.160.0/23103.63.160.1 to 103.63.161.254103.63.161.255510
82103.63.162.0/23103.63.162.1 to 103.63.163.254103.63.163.255510
83103.63.164.0/23103.63.164.1 to 103.63.165.254103.63.165.255510
84103.63.166.0/23103.63.166.1 to 103.63.167.254103.63.167.255510
85103.63.168.0/23103.63.168.1 to 103.63.169.254103.63.169.255510
86103.63.170.0/23103.63.170.1 to 103.63.171.254103.63.171.255510
87103.63.172.0/23103.63.172.1 to 103.63.173.254103.63.173.255510
88103.63.174.0/23103.63.174.1 to 103.63.175.254103.63.175.255510
89103.63.176.0/23103.63.176.1 to 103.63.177.254103.63.177.255510
90103.63.178.0/23103.63.178.1 to 103.63.179.254103.63.179.255510
91103.63.180.0/23103.63.180.1 to 103.63.181.254103.63.181.255510
92103.63.182.0/23103.63.182.1 to 103.63.183.254103.63.183.255510
93103.63.184.0/23103.63.184.1 to 103.63.185.254103.63.185.255510
94103.63.186.0/23103.63.186.1 to 103.63.187.254103.63.187.255510
95103.63.188.0/23103.63.188.1 to 103.63.189.254103.63.189.255510
96103.63.190.0/23103.63.190.1 to 103.63.191.254103.63.191.255510
97103.63.192.0/23103.63.192.1 to 103.63.193.254103.63.193.255510
98103.63.194.0/23103.63.194.1 to 103.63.195.254103.63.195.255510
99103.63.196.0/23103.63.196.1 to 103.63.197.254103.63.197.255510
100103.63.198.0/23103.63.198.1 to 103.63.199.254103.63.199.255510
101103.63.200.0/23103.63.200.1 to 103.63.201.254103.63.201.255510
102103.63.202.0/23103.63.202.1 to 103.63.203.254103.63.203.255510
103103.63.204.0/23103.63.204.1 to 103.63.205.254103.63.205.255510
104103.63.206.0/23103.63.206.1 to 103.63.207.254103.63.207.255510
105103.63.208.0/23103.63.208.1 to 103.63.209.254103.63.209.255510
106103.63.210.0/23103.63.210.1 to 103.63.211.254103.63.211.255510
107103.63.212.0/23103.63.212.1 to 103.63.213.254103.63.213.255510
108103.63.214.0/23103.63.214.1 to 103.63.215.254103.63.215.255510
109103.63.216.0/23103.63.216.1 to 103.63.217.254103.63.217.255510
110103.63.218.0/23103.63.218.1 to 103.63.219.254103.63.219.255510
111103.63.220.0/23103.63.220.1 to 103.63.221.254103.63.221.255510
112103.63.222.0/23103.63.222.1 to 103.63.223.254103.63.223.255510
113103.63.224.0/23103.63.224.1 to 103.63.225.254103.63.225.255510
114103.63.226.0/23103.63.226.1 to 103.63.227.254103.63.227.255510
115103.63.228.0/23103.63.228.1 to 103.63.229.254103.63.229.255510
116103.63.230.0/23103.63.230.1 to 103.63.231.254103.63.231.255510
117103.63.232.0/23103.63.232.1 to 103.63.233.254103.63.233.255510
118103.63.234.0/23103.63.234.1 to 103.63.235.254103.63.235.255510
119103.63.236.0/23103.63.236.1 to 103.63.237.254103.63.237.255510
120103.63.238.0/23103.63.238.1 to 103.63.239.254103.63.239.255510
121103.63.240.0/23103.63.240.1 to 103.63.241.254103.63.241.255510
122103.63.242.0/23103.63.242.1 to 103.63.243.254103.63.243.255510
123103.63.244.0/23103.63.244.1 to 103.63.245.254103.63.245.255510
124103.63.246.0/23103.63.246.1 to 103.63.247.254103.63.247.255510
125103.63.248.0/23103.63.248.1 to 103.63.249.254103.63.249.255510
126103.63.250.0/23103.63.250.1 to 103.63.251.254103.63.251.255510
127103.63.252.0/23103.63.252.1 to 103.63.253.254103.63.253.255510
128103.63.254.0/23103.63.254.1 to 103.63.255.254103.63.255.255510

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