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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.

Network114.76.0.0/14
Usable hosts262,142
Subnet mask255.252.0.0
Addresses262,144
Network address
114.76.0.0
Broadcast address
114.79.255.255
First usable
114.76.0.1
Last usable
114.79.255.254
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
A (default /8)
As numbers
Hex 724C0000 · Integer 1917583360 to 1917845503
Reverse DNS zones
76.114.in-addr.arpa
77.114.in-addr.arpa
78.114.in-addr.arpa
79.114.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
Address01110010.01001100.00000000.00000000114.76.0.0
Subnet mask11111111.11111100.00000000.00000000255.252.0.0
Network01110010.01001100.00000000.00000000114.76.0.0
Broadcast01110010.01001111.11111111.11111111114.79.255.255
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)

114.76.0.0/14 makes 128 subnets of /21.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
1114.76.0.0/21114.76.0.1 to 114.76.7.254114.76.7.2552,046
2114.76.8.0/21114.76.8.1 to 114.76.15.254114.76.15.2552,046
3114.76.16.0/21114.76.16.1 to 114.76.23.254114.76.23.2552,046
4114.76.24.0/21114.76.24.1 to 114.76.31.254114.76.31.2552,046
5114.76.32.0/21114.76.32.1 to 114.76.39.254114.76.39.2552,046
6114.76.40.0/21114.76.40.1 to 114.76.47.254114.76.47.2552,046
7114.76.48.0/21114.76.48.1 to 114.76.55.254114.76.55.2552,046
8114.76.56.0/21114.76.56.1 to 114.76.63.254114.76.63.2552,046
9114.76.64.0/21114.76.64.1 to 114.76.71.254114.76.71.2552,046
10114.76.72.0/21114.76.72.1 to 114.76.79.254114.76.79.2552,046
11114.76.80.0/21114.76.80.1 to 114.76.87.254114.76.87.2552,046
12114.76.88.0/21114.76.88.1 to 114.76.95.254114.76.95.2552,046
13114.76.96.0/21114.76.96.1 to 114.76.103.254114.76.103.2552,046
14114.76.104.0/21114.76.104.1 to 114.76.111.254114.76.111.2552,046
15114.76.112.0/21114.76.112.1 to 114.76.119.254114.76.119.2552,046
16114.76.120.0/21114.76.120.1 to 114.76.127.254114.76.127.2552,046
17114.76.128.0/21114.76.128.1 to 114.76.135.254114.76.135.2552,046
18114.76.136.0/21114.76.136.1 to 114.76.143.254114.76.143.2552,046
19114.76.144.0/21114.76.144.1 to 114.76.151.254114.76.151.2552,046
20114.76.152.0/21114.76.152.1 to 114.76.159.254114.76.159.2552,046
21114.76.160.0/21114.76.160.1 to 114.76.167.254114.76.167.2552,046
22114.76.168.0/21114.76.168.1 to 114.76.175.254114.76.175.2552,046
23114.76.176.0/21114.76.176.1 to 114.76.183.254114.76.183.2552,046
24114.76.184.0/21114.76.184.1 to 114.76.191.254114.76.191.2552,046
25114.76.192.0/21114.76.192.1 to 114.76.199.254114.76.199.2552,046
26114.76.200.0/21114.76.200.1 to 114.76.207.254114.76.207.2552,046
27114.76.208.0/21114.76.208.1 to 114.76.215.254114.76.215.2552,046
28114.76.216.0/21114.76.216.1 to 114.76.223.254114.76.223.2552,046
29114.76.224.0/21114.76.224.1 to 114.76.231.254114.76.231.2552,046
30114.76.232.0/21114.76.232.1 to 114.76.239.254114.76.239.2552,046
31114.76.240.0/21114.76.240.1 to 114.76.247.254114.76.247.2552,046
32114.76.248.0/21114.76.248.1 to 114.76.255.254114.76.255.2552,046
33114.77.0.0/21114.77.0.1 to 114.77.7.254114.77.7.2552,046
34114.77.8.0/21114.77.8.1 to 114.77.15.254114.77.15.2552,046
35114.77.16.0/21114.77.16.1 to 114.77.23.254114.77.23.2552,046
36114.77.24.0/21114.77.24.1 to 114.77.31.254114.77.31.2552,046
37114.77.32.0/21114.77.32.1 to 114.77.39.254114.77.39.2552,046
38114.77.40.0/21114.77.40.1 to 114.77.47.254114.77.47.2552,046
39114.77.48.0/21114.77.48.1 to 114.77.55.254114.77.55.2552,046
40114.77.56.0/21114.77.56.1 to 114.77.63.254114.77.63.2552,046
41114.77.64.0/21114.77.64.1 to 114.77.71.254114.77.71.2552,046
42114.77.72.0/21114.77.72.1 to 114.77.79.254114.77.79.2552,046
43114.77.80.0/21114.77.80.1 to 114.77.87.254114.77.87.2552,046
44114.77.88.0/21114.77.88.1 to 114.77.95.254114.77.95.2552,046
45114.77.96.0/21114.77.96.1 to 114.77.103.254114.77.103.2552,046
46114.77.104.0/21114.77.104.1 to 114.77.111.254114.77.111.2552,046
47114.77.112.0/21114.77.112.1 to 114.77.119.254114.77.119.2552,046
48114.77.120.0/21114.77.120.1 to 114.77.127.254114.77.127.2552,046
49114.77.128.0/21114.77.128.1 to 114.77.135.254114.77.135.2552,046
50114.77.136.0/21114.77.136.1 to 114.77.143.254114.77.143.2552,046
51114.77.144.0/21114.77.144.1 to 114.77.151.254114.77.151.2552,046
52114.77.152.0/21114.77.152.1 to 114.77.159.254114.77.159.2552,046
53114.77.160.0/21114.77.160.1 to 114.77.167.254114.77.167.2552,046
54114.77.168.0/21114.77.168.1 to 114.77.175.254114.77.175.2552,046
55114.77.176.0/21114.77.176.1 to 114.77.183.254114.77.183.2552,046
56114.77.184.0/21114.77.184.1 to 114.77.191.254114.77.191.2552,046
57114.77.192.0/21114.77.192.1 to 114.77.199.254114.77.199.2552,046
58114.77.200.0/21114.77.200.1 to 114.77.207.254114.77.207.2552,046
59114.77.208.0/21114.77.208.1 to 114.77.215.254114.77.215.2552,046
60114.77.216.0/21114.77.216.1 to 114.77.223.254114.77.223.2552,046
61114.77.224.0/21114.77.224.1 to 114.77.231.254114.77.231.2552,046
62114.77.232.0/21114.77.232.1 to 114.77.239.254114.77.239.2552,046
63114.77.240.0/21114.77.240.1 to 114.77.247.254114.77.247.2552,046
64114.77.248.0/21114.77.248.1 to 114.77.255.254114.77.255.2552,046
65114.78.0.0/21114.78.0.1 to 114.78.7.254114.78.7.2552,046
66114.78.8.0/21114.78.8.1 to 114.78.15.254114.78.15.2552,046
67114.78.16.0/21114.78.16.1 to 114.78.23.254114.78.23.2552,046
68114.78.24.0/21114.78.24.1 to 114.78.31.254114.78.31.2552,046
69114.78.32.0/21114.78.32.1 to 114.78.39.254114.78.39.2552,046
70114.78.40.0/21114.78.40.1 to 114.78.47.254114.78.47.2552,046
71114.78.48.0/21114.78.48.1 to 114.78.55.254114.78.55.2552,046
72114.78.56.0/21114.78.56.1 to 114.78.63.254114.78.63.2552,046
73114.78.64.0/21114.78.64.1 to 114.78.71.254114.78.71.2552,046
74114.78.72.0/21114.78.72.1 to 114.78.79.254114.78.79.2552,046
75114.78.80.0/21114.78.80.1 to 114.78.87.254114.78.87.2552,046
76114.78.88.0/21114.78.88.1 to 114.78.95.254114.78.95.2552,046
77114.78.96.0/21114.78.96.1 to 114.78.103.254114.78.103.2552,046
78114.78.104.0/21114.78.104.1 to 114.78.111.254114.78.111.2552,046
79114.78.112.0/21114.78.112.1 to 114.78.119.254114.78.119.2552,046
80114.78.120.0/21114.78.120.1 to 114.78.127.254114.78.127.2552,046
81114.78.128.0/21114.78.128.1 to 114.78.135.254114.78.135.2552,046
82114.78.136.0/21114.78.136.1 to 114.78.143.254114.78.143.2552,046
83114.78.144.0/21114.78.144.1 to 114.78.151.254114.78.151.2552,046
84114.78.152.0/21114.78.152.1 to 114.78.159.254114.78.159.2552,046
85114.78.160.0/21114.78.160.1 to 114.78.167.254114.78.167.2552,046
86114.78.168.0/21114.78.168.1 to 114.78.175.254114.78.175.2552,046
87114.78.176.0/21114.78.176.1 to 114.78.183.254114.78.183.2552,046
88114.78.184.0/21114.78.184.1 to 114.78.191.254114.78.191.2552,046
89114.78.192.0/21114.78.192.1 to 114.78.199.254114.78.199.2552,046
90114.78.200.0/21114.78.200.1 to 114.78.207.254114.78.207.2552,046
91114.78.208.0/21114.78.208.1 to 114.78.215.254114.78.215.2552,046
92114.78.216.0/21114.78.216.1 to 114.78.223.254114.78.223.2552,046
93114.78.224.0/21114.78.224.1 to 114.78.231.254114.78.231.2552,046
94114.78.232.0/21114.78.232.1 to 114.78.239.254114.78.239.2552,046
95114.78.240.0/21114.78.240.1 to 114.78.247.254114.78.247.2552,046
96114.78.248.0/21114.78.248.1 to 114.78.255.254114.78.255.2552,046
97114.79.0.0/21114.79.0.1 to 114.79.7.254114.79.7.2552,046
98114.79.8.0/21114.79.8.1 to 114.79.15.254114.79.15.2552,046
99114.79.16.0/21114.79.16.1 to 114.79.23.254114.79.23.2552,046
100114.79.24.0/21114.79.24.1 to 114.79.31.254114.79.31.2552,046
101114.79.32.0/21114.79.32.1 to 114.79.39.254114.79.39.2552,046
102114.79.40.0/21114.79.40.1 to 114.79.47.254114.79.47.2552,046
103114.79.48.0/21114.79.48.1 to 114.79.55.254114.79.55.2552,046
104114.79.56.0/21114.79.56.1 to 114.79.63.254114.79.63.2552,046
105114.79.64.0/21114.79.64.1 to 114.79.71.254114.79.71.2552,046
106114.79.72.0/21114.79.72.1 to 114.79.79.254114.79.79.2552,046
107114.79.80.0/21114.79.80.1 to 114.79.87.254114.79.87.2552,046
108114.79.88.0/21114.79.88.1 to 114.79.95.254114.79.95.2552,046
109114.79.96.0/21114.79.96.1 to 114.79.103.254114.79.103.2552,046
110114.79.104.0/21114.79.104.1 to 114.79.111.254114.79.111.2552,046
111114.79.112.0/21114.79.112.1 to 114.79.119.254114.79.119.2552,046
112114.79.120.0/21114.79.120.1 to 114.79.127.254114.79.127.2552,046
113114.79.128.0/21114.79.128.1 to 114.79.135.254114.79.135.2552,046
114114.79.136.0/21114.79.136.1 to 114.79.143.254114.79.143.2552,046
115114.79.144.0/21114.79.144.1 to 114.79.151.254114.79.151.2552,046
116114.79.152.0/21114.79.152.1 to 114.79.159.254114.79.159.2552,046
117114.79.160.0/21114.79.160.1 to 114.79.167.254114.79.167.2552,046
118114.79.168.0/21114.79.168.1 to 114.79.175.254114.79.175.2552,046
119114.79.176.0/21114.79.176.1 to 114.79.183.254114.79.183.2552,046
120114.79.184.0/21114.79.184.1 to 114.79.191.254114.79.191.2552,046
121114.79.192.0/21114.79.192.1 to 114.79.199.254114.79.199.2552,046
122114.79.200.0/21114.79.200.1 to 114.79.207.254114.79.207.2552,046
123114.79.208.0/21114.79.208.1 to 114.79.215.254114.79.215.2552,046
124114.79.216.0/21114.79.216.1 to 114.79.223.254114.79.223.2552,046
125114.79.224.0/21114.79.224.1 to 114.79.231.254114.79.231.2552,046
126114.79.232.0/21114.79.232.1 to 114.79.239.254114.79.239.2552,046
127114.79.240.0/21114.79.240.1 to 114.79.247.254114.79.247.2552,046
128114.79.248.0/21114.79.248.1 to 114.79.255.254114.79.255.2552,046

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.