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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.

Network175.232.0.0/14
Usable hosts262,142
Subnet mask255.252.0.0
Addresses262,144
Network address
175.232.0.0
Broadcast address
175.235.255.255
First usable
175.232.0.1
Last usable
175.235.255.254
Usable hosts
262,142 (262,144 less the network and broadcast addresses)
Subnet mask
255.252.0.0
Wildcard mask
0.3.255.255 (Cisco ACLs, OSPF)
Prefix length
/14
Type
Public public
Old class
B (default /16)
As numbers
Hex AFE80000 · Integer 2951217152 to 2951479295
Reverse DNS zones
232.175.in-addr.arpa
233.175.in-addr.arpa
234.175.in-addr.arpa
235.175.in-addr.arpa
/14 is not on a 8-bit boundary, so it takes 4 /16 zones.
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address10101111.11101000.00000000.00000000175.232.0.0
Subnet mask11111111.11111100.00000000.00000000255.252.0.0
Network10101111.11101000.00000000.00000000175.232.0.0
Broadcast10101111.11101011.11111111.11111111175.235.255.255
Split into smaller subnets/21
/15 (2)/16 (4)/17 (8)/18 (16)/19 (32)/20 (64)/21 (128)/22 (256)/23 (512)/24 (1,024)/25 (2,048)/26 (4,096)

175.232.0.0/14 makes 128 subnets of /21.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
1175.232.0.0/21175.232.0.1 to 175.232.7.254175.232.7.2552,046
2175.232.8.0/21175.232.8.1 to 175.232.15.254175.232.15.2552,046
3175.232.16.0/21175.232.16.1 to 175.232.23.254175.232.23.2552,046
4175.232.24.0/21175.232.24.1 to 175.232.31.254175.232.31.2552,046
5175.232.32.0/21175.232.32.1 to 175.232.39.254175.232.39.2552,046
6175.232.40.0/21175.232.40.1 to 175.232.47.254175.232.47.2552,046
7175.232.48.0/21175.232.48.1 to 175.232.55.254175.232.55.2552,046
8175.232.56.0/21175.232.56.1 to 175.232.63.254175.232.63.2552,046
9175.232.64.0/21175.232.64.1 to 175.232.71.254175.232.71.2552,046
10175.232.72.0/21175.232.72.1 to 175.232.79.254175.232.79.2552,046
11175.232.80.0/21175.232.80.1 to 175.232.87.254175.232.87.2552,046
12175.232.88.0/21175.232.88.1 to 175.232.95.254175.232.95.2552,046
13175.232.96.0/21175.232.96.1 to 175.232.103.254175.232.103.2552,046
14175.232.104.0/21175.232.104.1 to 175.232.111.254175.232.111.2552,046
15175.232.112.0/21175.232.112.1 to 175.232.119.254175.232.119.2552,046
16175.232.120.0/21175.232.120.1 to 175.232.127.254175.232.127.2552,046
17175.232.128.0/21175.232.128.1 to 175.232.135.254175.232.135.2552,046
18175.232.136.0/21175.232.136.1 to 175.232.143.254175.232.143.2552,046
19175.232.144.0/21175.232.144.1 to 175.232.151.254175.232.151.2552,046
20175.232.152.0/21175.232.152.1 to 175.232.159.254175.232.159.2552,046
21175.232.160.0/21175.232.160.1 to 175.232.167.254175.232.167.2552,046
22175.232.168.0/21175.232.168.1 to 175.232.175.254175.232.175.2552,046
23175.232.176.0/21175.232.176.1 to 175.232.183.254175.232.183.2552,046
24175.232.184.0/21175.232.184.1 to 175.232.191.254175.232.191.2552,046
25175.232.192.0/21175.232.192.1 to 175.232.199.254175.232.199.2552,046
26175.232.200.0/21175.232.200.1 to 175.232.207.254175.232.207.2552,046
27175.232.208.0/21175.232.208.1 to 175.232.215.254175.232.215.2552,046
28175.232.216.0/21175.232.216.1 to 175.232.223.254175.232.223.2552,046
29175.232.224.0/21175.232.224.1 to 175.232.231.254175.232.231.2552,046
30175.232.232.0/21175.232.232.1 to 175.232.239.254175.232.239.2552,046
31175.232.240.0/21175.232.240.1 to 175.232.247.254175.232.247.2552,046
32175.232.248.0/21175.232.248.1 to 175.232.255.254175.232.255.2552,046
33175.233.0.0/21175.233.0.1 to 175.233.7.254175.233.7.2552,046
34175.233.8.0/21175.233.8.1 to 175.233.15.254175.233.15.2552,046
35175.233.16.0/21175.233.16.1 to 175.233.23.254175.233.23.2552,046
36175.233.24.0/21175.233.24.1 to 175.233.31.254175.233.31.2552,046
37175.233.32.0/21175.233.32.1 to 175.233.39.254175.233.39.2552,046
38175.233.40.0/21175.233.40.1 to 175.233.47.254175.233.47.2552,046
39175.233.48.0/21175.233.48.1 to 175.233.55.254175.233.55.2552,046
40175.233.56.0/21175.233.56.1 to 175.233.63.254175.233.63.2552,046
41175.233.64.0/21175.233.64.1 to 175.233.71.254175.233.71.2552,046
42175.233.72.0/21175.233.72.1 to 175.233.79.254175.233.79.2552,046
43175.233.80.0/21175.233.80.1 to 175.233.87.254175.233.87.2552,046
44175.233.88.0/21175.233.88.1 to 175.233.95.254175.233.95.2552,046
45175.233.96.0/21175.233.96.1 to 175.233.103.254175.233.103.2552,046
46175.233.104.0/21175.233.104.1 to 175.233.111.254175.233.111.2552,046
47175.233.112.0/21175.233.112.1 to 175.233.119.254175.233.119.2552,046
48175.233.120.0/21175.233.120.1 to 175.233.127.254175.233.127.2552,046
49175.233.128.0/21175.233.128.1 to 175.233.135.254175.233.135.2552,046
50175.233.136.0/21175.233.136.1 to 175.233.143.254175.233.143.2552,046
51175.233.144.0/21175.233.144.1 to 175.233.151.254175.233.151.2552,046
52175.233.152.0/21175.233.152.1 to 175.233.159.254175.233.159.2552,046
53175.233.160.0/21175.233.160.1 to 175.233.167.254175.233.167.2552,046
54175.233.168.0/21175.233.168.1 to 175.233.175.254175.233.175.2552,046
55175.233.176.0/21175.233.176.1 to 175.233.183.254175.233.183.2552,046
56175.233.184.0/21175.233.184.1 to 175.233.191.254175.233.191.2552,046
57175.233.192.0/21175.233.192.1 to 175.233.199.254175.233.199.2552,046
58175.233.200.0/21175.233.200.1 to 175.233.207.254175.233.207.2552,046
59175.233.208.0/21175.233.208.1 to 175.233.215.254175.233.215.2552,046
60175.233.216.0/21175.233.216.1 to 175.233.223.254175.233.223.2552,046
61175.233.224.0/21175.233.224.1 to 175.233.231.254175.233.231.2552,046
62175.233.232.0/21175.233.232.1 to 175.233.239.254175.233.239.2552,046
63175.233.240.0/21175.233.240.1 to 175.233.247.254175.233.247.2552,046
64175.233.248.0/21175.233.248.1 to 175.233.255.254175.233.255.2552,046
65175.234.0.0/21175.234.0.1 to 175.234.7.254175.234.7.2552,046
66175.234.8.0/21175.234.8.1 to 175.234.15.254175.234.15.2552,046
67175.234.16.0/21175.234.16.1 to 175.234.23.254175.234.23.2552,046
68175.234.24.0/21175.234.24.1 to 175.234.31.254175.234.31.2552,046
69175.234.32.0/21175.234.32.1 to 175.234.39.254175.234.39.2552,046
70175.234.40.0/21175.234.40.1 to 175.234.47.254175.234.47.2552,046
71175.234.48.0/21175.234.48.1 to 175.234.55.254175.234.55.2552,046
72175.234.56.0/21175.234.56.1 to 175.234.63.254175.234.63.2552,046
73175.234.64.0/21175.234.64.1 to 175.234.71.254175.234.71.2552,046
74175.234.72.0/21175.234.72.1 to 175.234.79.254175.234.79.2552,046
75175.234.80.0/21175.234.80.1 to 175.234.87.254175.234.87.2552,046
76175.234.88.0/21175.234.88.1 to 175.234.95.254175.234.95.2552,046
77175.234.96.0/21175.234.96.1 to 175.234.103.254175.234.103.2552,046
78175.234.104.0/21175.234.104.1 to 175.234.111.254175.234.111.2552,046
79175.234.112.0/21175.234.112.1 to 175.234.119.254175.234.119.2552,046
80175.234.120.0/21175.234.120.1 to 175.234.127.254175.234.127.2552,046
81175.234.128.0/21175.234.128.1 to 175.234.135.254175.234.135.2552,046
82175.234.136.0/21175.234.136.1 to 175.234.143.254175.234.143.2552,046
83175.234.144.0/21175.234.144.1 to 175.234.151.254175.234.151.2552,046
84175.234.152.0/21175.234.152.1 to 175.234.159.254175.234.159.2552,046
85175.234.160.0/21175.234.160.1 to 175.234.167.254175.234.167.2552,046
86175.234.168.0/21175.234.168.1 to 175.234.175.254175.234.175.2552,046
87175.234.176.0/21175.234.176.1 to 175.234.183.254175.234.183.2552,046
88175.234.184.0/21175.234.184.1 to 175.234.191.254175.234.191.2552,046
89175.234.192.0/21175.234.192.1 to 175.234.199.254175.234.199.2552,046
90175.234.200.0/21175.234.200.1 to 175.234.207.254175.234.207.2552,046
91175.234.208.0/21175.234.208.1 to 175.234.215.254175.234.215.2552,046
92175.234.216.0/21175.234.216.1 to 175.234.223.254175.234.223.2552,046
93175.234.224.0/21175.234.224.1 to 175.234.231.254175.234.231.2552,046
94175.234.232.0/21175.234.232.1 to 175.234.239.254175.234.239.2552,046
95175.234.240.0/21175.234.240.1 to 175.234.247.254175.234.247.2552,046
96175.234.248.0/21175.234.248.1 to 175.234.255.254175.234.255.2552,046
97175.235.0.0/21175.235.0.1 to 175.235.7.254175.235.7.2552,046
98175.235.8.0/21175.235.8.1 to 175.235.15.254175.235.15.2552,046
99175.235.16.0/21175.235.16.1 to 175.235.23.254175.235.23.2552,046
100175.235.24.0/21175.235.24.1 to 175.235.31.254175.235.31.2552,046
101175.235.32.0/21175.235.32.1 to 175.235.39.254175.235.39.2552,046
102175.235.40.0/21175.235.40.1 to 175.235.47.254175.235.47.2552,046
103175.235.48.0/21175.235.48.1 to 175.235.55.254175.235.55.2552,046
104175.235.56.0/21175.235.56.1 to 175.235.63.254175.235.63.2552,046
105175.235.64.0/21175.235.64.1 to 175.235.71.254175.235.71.2552,046
106175.235.72.0/21175.235.72.1 to 175.235.79.254175.235.79.2552,046
107175.235.80.0/21175.235.80.1 to 175.235.87.254175.235.87.2552,046
108175.235.88.0/21175.235.88.1 to 175.235.95.254175.235.95.2552,046
109175.235.96.0/21175.235.96.1 to 175.235.103.254175.235.103.2552,046
110175.235.104.0/21175.235.104.1 to 175.235.111.254175.235.111.2552,046
111175.235.112.0/21175.235.112.1 to 175.235.119.254175.235.119.2552,046
112175.235.120.0/21175.235.120.1 to 175.235.127.254175.235.127.2552,046
113175.235.128.0/21175.235.128.1 to 175.235.135.254175.235.135.2552,046
114175.235.136.0/21175.235.136.1 to 175.235.143.254175.235.143.2552,046
115175.235.144.0/21175.235.144.1 to 175.235.151.254175.235.151.2552,046
116175.235.152.0/21175.235.152.1 to 175.235.159.254175.235.159.2552,046
117175.235.160.0/21175.235.160.1 to 175.235.167.254175.235.167.2552,046
118175.235.168.0/21175.235.168.1 to 175.235.175.254175.235.175.2552,046
119175.235.176.0/21175.235.176.1 to 175.235.183.254175.235.183.2552,046
120175.235.184.0/21175.235.184.1 to 175.235.191.254175.235.191.2552,046
121175.235.192.0/21175.235.192.1 to 175.235.199.254175.235.199.2552,046
122175.235.200.0/21175.235.200.1 to 175.235.207.254175.235.207.2552,046
123175.235.208.0/21175.235.208.1 to 175.235.215.254175.235.215.2552,046
124175.235.216.0/21175.235.216.1 to 175.235.223.254175.235.223.2552,046
125175.235.224.0/21175.235.224.1 to 175.235.231.254175.235.231.2552,046
126175.235.232.0/21175.235.232.1 to 175.235.239.254175.235.239.2552,046
127175.235.240.0/21175.235.240.1 to 175.235.247.254175.235.247.2552,046
128175.235.248.0/21175.235.248.1 to 175.235.255.254175.235.255.2552,046

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.