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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.

Network119.0.0.0/11
Usable hosts2,097,150
Subnet mask255.224.0.0
Addresses2,097,152
Network address
119.0.0.0
Broadcast address
119.31.255.255
First usable
119.0.0.1
Last usable
119.31.255.254
Usable hosts
2,097,150 (2,097,152 less the network and broadcast addresses)
Subnet mask
255.224.0.0
Wildcard mask
0.31.255.255 (Cisco ACLs, OSPF)
Prefix length
/11
Type
Public public
Old class
A (default /8)
As numbers
Hex 77000000 · Integer 1996488704 to 1998585855
Reverse DNS zones
0.119.in-addr.arpa
1.119.in-addr.arpa
2.119.in-addr.arpa
3.119.in-addr.arpa
4.119.in-addr.arpa
5.119.in-addr.arpa
6.119.in-addr.arpa
7.119.in-addr.arpa
8.119.in-addr.arpa
9.119.in-addr.arpa
10.119.in-addr.arpa
11.119.in-addr.arpa
12.119.in-addr.arpa
13.119.in-addr.arpa
14.119.in-addr.arpa
15.119.in-addr.arpa
and 16 more
/11 is not on a 8-bit boundary, so it takes 32 /16 zones.
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address01110111.00000000.00000000.00000000119.0.0.0
Subnet mask11111111.11100000.00000000.00000000255.224.0.0
Network01110111.00000000.00000000.00000000119.0.0.0
Broadcast01110111.00011111.11111111.11111111119.31.255.255
Split into smaller subnets/18
/12 (2)/13 (4)/14 (8)/15 (16)/16 (32)/17 (64)/18 (128)/19 (256)/20 (512)/21 (1,024)/22 (2,048)/23 (4,096)

119.0.0.0/11 makes 128 subnets of /18.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
1119.0.0.0/18119.0.0.1 to 119.0.63.254119.0.63.25516,382
2119.0.64.0/18119.0.64.1 to 119.0.127.254119.0.127.25516,382
3119.0.128.0/18119.0.128.1 to 119.0.191.254119.0.191.25516,382
4119.0.192.0/18119.0.192.1 to 119.0.255.254119.0.255.25516,382
5119.1.0.0/18119.1.0.1 to 119.1.63.254119.1.63.25516,382
6119.1.64.0/18119.1.64.1 to 119.1.127.254119.1.127.25516,382
7119.1.128.0/18119.1.128.1 to 119.1.191.254119.1.191.25516,382
8119.1.192.0/18119.1.192.1 to 119.1.255.254119.1.255.25516,382
9119.2.0.0/18119.2.0.1 to 119.2.63.254119.2.63.25516,382
10119.2.64.0/18119.2.64.1 to 119.2.127.254119.2.127.25516,382
11119.2.128.0/18119.2.128.1 to 119.2.191.254119.2.191.25516,382
12119.2.192.0/18119.2.192.1 to 119.2.255.254119.2.255.25516,382
13119.3.0.0/18119.3.0.1 to 119.3.63.254119.3.63.25516,382
14119.3.64.0/18119.3.64.1 to 119.3.127.254119.3.127.25516,382
15119.3.128.0/18119.3.128.1 to 119.3.191.254119.3.191.25516,382
16119.3.192.0/18119.3.192.1 to 119.3.255.254119.3.255.25516,382
17119.4.0.0/18119.4.0.1 to 119.4.63.254119.4.63.25516,382
18119.4.64.0/18119.4.64.1 to 119.4.127.254119.4.127.25516,382
19119.4.128.0/18119.4.128.1 to 119.4.191.254119.4.191.25516,382
20119.4.192.0/18119.4.192.1 to 119.4.255.254119.4.255.25516,382
21119.5.0.0/18119.5.0.1 to 119.5.63.254119.5.63.25516,382
22119.5.64.0/18119.5.64.1 to 119.5.127.254119.5.127.25516,382
23119.5.128.0/18119.5.128.1 to 119.5.191.254119.5.191.25516,382
24119.5.192.0/18119.5.192.1 to 119.5.255.254119.5.255.25516,382
25119.6.0.0/18119.6.0.1 to 119.6.63.254119.6.63.25516,382
26119.6.64.0/18119.6.64.1 to 119.6.127.254119.6.127.25516,382
27119.6.128.0/18119.6.128.1 to 119.6.191.254119.6.191.25516,382
28119.6.192.0/18119.6.192.1 to 119.6.255.254119.6.255.25516,382
29119.7.0.0/18119.7.0.1 to 119.7.63.254119.7.63.25516,382
30119.7.64.0/18119.7.64.1 to 119.7.127.254119.7.127.25516,382
31119.7.128.0/18119.7.128.1 to 119.7.191.254119.7.191.25516,382
32119.7.192.0/18119.7.192.1 to 119.7.255.254119.7.255.25516,382
33119.8.0.0/18119.8.0.1 to 119.8.63.254119.8.63.25516,382
34119.8.64.0/18119.8.64.1 to 119.8.127.254119.8.127.25516,382
35119.8.128.0/18119.8.128.1 to 119.8.191.254119.8.191.25516,382
36119.8.192.0/18119.8.192.1 to 119.8.255.254119.8.255.25516,382
37119.9.0.0/18119.9.0.1 to 119.9.63.254119.9.63.25516,382
38119.9.64.0/18119.9.64.1 to 119.9.127.254119.9.127.25516,382
39119.9.128.0/18119.9.128.1 to 119.9.191.254119.9.191.25516,382
40119.9.192.0/18119.9.192.1 to 119.9.255.254119.9.255.25516,382
41119.10.0.0/18119.10.0.1 to 119.10.63.254119.10.63.25516,382
42119.10.64.0/18119.10.64.1 to 119.10.127.254119.10.127.25516,382
43119.10.128.0/18119.10.128.1 to 119.10.191.254119.10.191.25516,382
44119.10.192.0/18119.10.192.1 to 119.10.255.254119.10.255.25516,382
45119.11.0.0/18119.11.0.1 to 119.11.63.254119.11.63.25516,382
46119.11.64.0/18119.11.64.1 to 119.11.127.254119.11.127.25516,382
47119.11.128.0/18119.11.128.1 to 119.11.191.254119.11.191.25516,382
48119.11.192.0/18119.11.192.1 to 119.11.255.254119.11.255.25516,382
49119.12.0.0/18119.12.0.1 to 119.12.63.254119.12.63.25516,382
50119.12.64.0/18119.12.64.1 to 119.12.127.254119.12.127.25516,382
51119.12.128.0/18119.12.128.1 to 119.12.191.254119.12.191.25516,382
52119.12.192.0/18119.12.192.1 to 119.12.255.254119.12.255.25516,382
53119.13.0.0/18119.13.0.1 to 119.13.63.254119.13.63.25516,382
54119.13.64.0/18119.13.64.1 to 119.13.127.254119.13.127.25516,382
55119.13.128.0/18119.13.128.1 to 119.13.191.254119.13.191.25516,382
56119.13.192.0/18119.13.192.1 to 119.13.255.254119.13.255.25516,382
57119.14.0.0/18119.14.0.1 to 119.14.63.254119.14.63.25516,382
58119.14.64.0/18119.14.64.1 to 119.14.127.254119.14.127.25516,382
59119.14.128.0/18119.14.128.1 to 119.14.191.254119.14.191.25516,382
60119.14.192.0/18119.14.192.1 to 119.14.255.254119.14.255.25516,382
61119.15.0.0/18119.15.0.1 to 119.15.63.254119.15.63.25516,382
62119.15.64.0/18119.15.64.1 to 119.15.127.254119.15.127.25516,382
63119.15.128.0/18119.15.128.1 to 119.15.191.254119.15.191.25516,382
64119.15.192.0/18119.15.192.1 to 119.15.255.254119.15.255.25516,382
65119.16.0.0/18119.16.0.1 to 119.16.63.254119.16.63.25516,382
66119.16.64.0/18119.16.64.1 to 119.16.127.254119.16.127.25516,382
67119.16.128.0/18119.16.128.1 to 119.16.191.254119.16.191.25516,382
68119.16.192.0/18119.16.192.1 to 119.16.255.254119.16.255.25516,382
69119.17.0.0/18119.17.0.1 to 119.17.63.254119.17.63.25516,382
70119.17.64.0/18119.17.64.1 to 119.17.127.254119.17.127.25516,382
71119.17.128.0/18119.17.128.1 to 119.17.191.254119.17.191.25516,382
72119.17.192.0/18119.17.192.1 to 119.17.255.254119.17.255.25516,382
73119.18.0.0/18119.18.0.1 to 119.18.63.254119.18.63.25516,382
74119.18.64.0/18119.18.64.1 to 119.18.127.254119.18.127.25516,382
75119.18.128.0/18119.18.128.1 to 119.18.191.254119.18.191.25516,382
76119.18.192.0/18119.18.192.1 to 119.18.255.254119.18.255.25516,382
77119.19.0.0/18119.19.0.1 to 119.19.63.254119.19.63.25516,382
78119.19.64.0/18119.19.64.1 to 119.19.127.254119.19.127.25516,382
79119.19.128.0/18119.19.128.1 to 119.19.191.254119.19.191.25516,382
80119.19.192.0/18119.19.192.1 to 119.19.255.254119.19.255.25516,382
81119.20.0.0/18119.20.0.1 to 119.20.63.254119.20.63.25516,382
82119.20.64.0/18119.20.64.1 to 119.20.127.254119.20.127.25516,382
83119.20.128.0/18119.20.128.1 to 119.20.191.254119.20.191.25516,382
84119.20.192.0/18119.20.192.1 to 119.20.255.254119.20.255.25516,382
85119.21.0.0/18119.21.0.1 to 119.21.63.254119.21.63.25516,382
86119.21.64.0/18119.21.64.1 to 119.21.127.254119.21.127.25516,382
87119.21.128.0/18119.21.128.1 to 119.21.191.254119.21.191.25516,382
88119.21.192.0/18119.21.192.1 to 119.21.255.254119.21.255.25516,382
89119.22.0.0/18119.22.0.1 to 119.22.63.254119.22.63.25516,382
90119.22.64.0/18119.22.64.1 to 119.22.127.254119.22.127.25516,382
91119.22.128.0/18119.22.128.1 to 119.22.191.254119.22.191.25516,382
92119.22.192.0/18119.22.192.1 to 119.22.255.254119.22.255.25516,382
93119.23.0.0/18119.23.0.1 to 119.23.63.254119.23.63.25516,382
94119.23.64.0/18119.23.64.1 to 119.23.127.254119.23.127.25516,382
95119.23.128.0/18119.23.128.1 to 119.23.191.254119.23.191.25516,382
96119.23.192.0/18119.23.192.1 to 119.23.255.254119.23.255.25516,382
97119.24.0.0/18119.24.0.1 to 119.24.63.254119.24.63.25516,382
98119.24.64.0/18119.24.64.1 to 119.24.127.254119.24.127.25516,382
99119.24.128.0/18119.24.128.1 to 119.24.191.254119.24.191.25516,382
100119.24.192.0/18119.24.192.1 to 119.24.255.254119.24.255.25516,382
101119.25.0.0/18119.25.0.1 to 119.25.63.254119.25.63.25516,382
102119.25.64.0/18119.25.64.1 to 119.25.127.254119.25.127.25516,382
103119.25.128.0/18119.25.128.1 to 119.25.191.254119.25.191.25516,382
104119.25.192.0/18119.25.192.1 to 119.25.255.254119.25.255.25516,382
105119.26.0.0/18119.26.0.1 to 119.26.63.254119.26.63.25516,382
106119.26.64.0/18119.26.64.1 to 119.26.127.254119.26.127.25516,382
107119.26.128.0/18119.26.128.1 to 119.26.191.254119.26.191.25516,382
108119.26.192.0/18119.26.192.1 to 119.26.255.254119.26.255.25516,382
109119.27.0.0/18119.27.0.1 to 119.27.63.254119.27.63.25516,382
110119.27.64.0/18119.27.64.1 to 119.27.127.254119.27.127.25516,382
111119.27.128.0/18119.27.128.1 to 119.27.191.254119.27.191.25516,382
112119.27.192.0/18119.27.192.1 to 119.27.255.254119.27.255.25516,382
113119.28.0.0/18119.28.0.1 to 119.28.63.254119.28.63.25516,382
114119.28.64.0/18119.28.64.1 to 119.28.127.254119.28.127.25516,382
115119.28.128.0/18119.28.128.1 to 119.28.191.254119.28.191.25516,382
116119.28.192.0/18119.28.192.1 to 119.28.255.254119.28.255.25516,382
117119.29.0.0/18119.29.0.1 to 119.29.63.254119.29.63.25516,382
118119.29.64.0/18119.29.64.1 to 119.29.127.254119.29.127.25516,382
119119.29.128.0/18119.29.128.1 to 119.29.191.254119.29.191.25516,382
120119.29.192.0/18119.29.192.1 to 119.29.255.254119.29.255.25516,382
121119.30.0.0/18119.30.0.1 to 119.30.63.254119.30.63.25516,382
122119.30.64.0/18119.30.64.1 to 119.30.127.254119.30.127.25516,382
123119.30.128.0/18119.30.128.1 to 119.30.191.254119.30.191.25516,382
124119.30.192.0/18119.30.192.1 to 119.30.255.254119.30.255.25516,382
125119.31.0.0/18119.31.0.1 to 119.31.63.254119.31.63.25516,382
126119.31.64.0/18119.31.64.1 to 119.31.127.254119.31.127.25516,382
127119.31.128.0/18119.31.128.1 to 119.31.191.254119.31.191.25516,382
128119.31.192.0/18119.31.192.1 to 119.31.255.254119.31.255.25516,382

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

About this tool

A network is written as an address and a prefix length, such as 192.168.1.0/24: the first 24 bits name the network and the rest number the devices on it. The calculator works out where the network starts and ends, how many devices it holds, its subnet and wildcard masks, and the reverse DNS zone to ask your provider for.

It also splits a network into equal smaller ones (one per VLAN or site), turns a range of addresses into the fewest CIDR blocks for a firewall rule, and lists every IPv4 prefix length and the common IPv6 ones in reference tables.

Common questions

Why are two addresses lost in every IPv4 subnet?

The first address names the network and the last is the broadcast address, so a /24 has 256 addresses but 254 for devices. A /31 (a link between two routers) and a /32 (one host) are the exceptions.

What size of IPv6 network should a LAN use?

Always /64. Devices pick their own address within it (SLAAC), which needs the full 64 bits. A site usually gets a /48 or /56 from its provider, which holds 65,536 or 256 LANs.

What is a wildcard mask?

The subnet mask turned inside out: 255.255.255.0 becomes 0.0.0.255. Cisco access lists and OSPF use it to say which bits must match.

Which ranges can I use inside an office?

IPv4: 10.0.0.0/8, 172.16.0.0/12 and 192.168.0.0/16. IPv6: unique local addresses from fd00::/8, though most networks use the public prefix from their provider.