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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.

Network174.76.0.0/14
Usable hosts262,142
Subnet mask255.252.0.0
Addresses262,144
Network address
174.76.0.0
Broadcast address
174.79.255.255
First usable
174.76.0.1
Last usable
174.79.255.254
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
B (default /16)
As numbers
Hex AE4C0000 · Integer 2924216320 to 2924478463
Reverse DNS zones
76.174.in-addr.arpa
77.174.in-addr.arpa
78.174.in-addr.arpa
79.174.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
Address10101110.01001100.00000000.00000000174.76.0.0
Subnet mask11111111.11111100.00000000.00000000255.252.0.0
Network10101110.01001100.00000000.00000000174.76.0.0
Broadcast10101110.01001111.11111111.11111111174.79.255.255
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)

174.76.0.0/14 makes 128 subnets of /21.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
1174.76.0.0/21174.76.0.1 to 174.76.7.254174.76.7.2552,046
2174.76.8.0/21174.76.8.1 to 174.76.15.254174.76.15.2552,046
3174.76.16.0/21174.76.16.1 to 174.76.23.254174.76.23.2552,046
4174.76.24.0/21174.76.24.1 to 174.76.31.254174.76.31.2552,046
5174.76.32.0/21174.76.32.1 to 174.76.39.254174.76.39.2552,046
6174.76.40.0/21174.76.40.1 to 174.76.47.254174.76.47.2552,046
7174.76.48.0/21174.76.48.1 to 174.76.55.254174.76.55.2552,046
8174.76.56.0/21174.76.56.1 to 174.76.63.254174.76.63.2552,046
9174.76.64.0/21174.76.64.1 to 174.76.71.254174.76.71.2552,046
10174.76.72.0/21174.76.72.1 to 174.76.79.254174.76.79.2552,046
11174.76.80.0/21174.76.80.1 to 174.76.87.254174.76.87.2552,046
12174.76.88.0/21174.76.88.1 to 174.76.95.254174.76.95.2552,046
13174.76.96.0/21174.76.96.1 to 174.76.103.254174.76.103.2552,046
14174.76.104.0/21174.76.104.1 to 174.76.111.254174.76.111.2552,046
15174.76.112.0/21174.76.112.1 to 174.76.119.254174.76.119.2552,046
16174.76.120.0/21174.76.120.1 to 174.76.127.254174.76.127.2552,046
17174.76.128.0/21174.76.128.1 to 174.76.135.254174.76.135.2552,046
18174.76.136.0/21174.76.136.1 to 174.76.143.254174.76.143.2552,046
19174.76.144.0/21174.76.144.1 to 174.76.151.254174.76.151.2552,046
20174.76.152.0/21174.76.152.1 to 174.76.159.254174.76.159.2552,046
21174.76.160.0/21174.76.160.1 to 174.76.167.254174.76.167.2552,046
22174.76.168.0/21174.76.168.1 to 174.76.175.254174.76.175.2552,046
23174.76.176.0/21174.76.176.1 to 174.76.183.254174.76.183.2552,046
24174.76.184.0/21174.76.184.1 to 174.76.191.254174.76.191.2552,046
25174.76.192.0/21174.76.192.1 to 174.76.199.254174.76.199.2552,046
26174.76.200.0/21174.76.200.1 to 174.76.207.254174.76.207.2552,046
27174.76.208.0/21174.76.208.1 to 174.76.215.254174.76.215.2552,046
28174.76.216.0/21174.76.216.1 to 174.76.223.254174.76.223.2552,046
29174.76.224.0/21174.76.224.1 to 174.76.231.254174.76.231.2552,046
30174.76.232.0/21174.76.232.1 to 174.76.239.254174.76.239.2552,046
31174.76.240.0/21174.76.240.1 to 174.76.247.254174.76.247.2552,046
32174.76.248.0/21174.76.248.1 to 174.76.255.254174.76.255.2552,046
33174.77.0.0/21174.77.0.1 to 174.77.7.254174.77.7.2552,046
34174.77.8.0/21174.77.8.1 to 174.77.15.254174.77.15.2552,046
35174.77.16.0/21174.77.16.1 to 174.77.23.254174.77.23.2552,046
36174.77.24.0/21174.77.24.1 to 174.77.31.254174.77.31.2552,046
37174.77.32.0/21174.77.32.1 to 174.77.39.254174.77.39.2552,046
38174.77.40.0/21174.77.40.1 to 174.77.47.254174.77.47.2552,046
39174.77.48.0/21174.77.48.1 to 174.77.55.254174.77.55.2552,046
40174.77.56.0/21174.77.56.1 to 174.77.63.254174.77.63.2552,046
41174.77.64.0/21174.77.64.1 to 174.77.71.254174.77.71.2552,046
42174.77.72.0/21174.77.72.1 to 174.77.79.254174.77.79.2552,046
43174.77.80.0/21174.77.80.1 to 174.77.87.254174.77.87.2552,046
44174.77.88.0/21174.77.88.1 to 174.77.95.254174.77.95.2552,046
45174.77.96.0/21174.77.96.1 to 174.77.103.254174.77.103.2552,046
46174.77.104.0/21174.77.104.1 to 174.77.111.254174.77.111.2552,046
47174.77.112.0/21174.77.112.1 to 174.77.119.254174.77.119.2552,046
48174.77.120.0/21174.77.120.1 to 174.77.127.254174.77.127.2552,046
49174.77.128.0/21174.77.128.1 to 174.77.135.254174.77.135.2552,046
50174.77.136.0/21174.77.136.1 to 174.77.143.254174.77.143.2552,046
51174.77.144.0/21174.77.144.1 to 174.77.151.254174.77.151.2552,046
52174.77.152.0/21174.77.152.1 to 174.77.159.254174.77.159.2552,046
53174.77.160.0/21174.77.160.1 to 174.77.167.254174.77.167.2552,046
54174.77.168.0/21174.77.168.1 to 174.77.175.254174.77.175.2552,046
55174.77.176.0/21174.77.176.1 to 174.77.183.254174.77.183.2552,046
56174.77.184.0/21174.77.184.1 to 174.77.191.254174.77.191.2552,046
57174.77.192.0/21174.77.192.1 to 174.77.199.254174.77.199.2552,046
58174.77.200.0/21174.77.200.1 to 174.77.207.254174.77.207.2552,046
59174.77.208.0/21174.77.208.1 to 174.77.215.254174.77.215.2552,046
60174.77.216.0/21174.77.216.1 to 174.77.223.254174.77.223.2552,046
61174.77.224.0/21174.77.224.1 to 174.77.231.254174.77.231.2552,046
62174.77.232.0/21174.77.232.1 to 174.77.239.254174.77.239.2552,046
63174.77.240.0/21174.77.240.1 to 174.77.247.254174.77.247.2552,046
64174.77.248.0/21174.77.248.1 to 174.77.255.254174.77.255.2552,046
65174.78.0.0/21174.78.0.1 to 174.78.7.254174.78.7.2552,046
66174.78.8.0/21174.78.8.1 to 174.78.15.254174.78.15.2552,046
67174.78.16.0/21174.78.16.1 to 174.78.23.254174.78.23.2552,046
68174.78.24.0/21174.78.24.1 to 174.78.31.254174.78.31.2552,046
69174.78.32.0/21174.78.32.1 to 174.78.39.254174.78.39.2552,046
70174.78.40.0/21174.78.40.1 to 174.78.47.254174.78.47.2552,046
71174.78.48.0/21174.78.48.1 to 174.78.55.254174.78.55.2552,046
72174.78.56.0/21174.78.56.1 to 174.78.63.254174.78.63.2552,046
73174.78.64.0/21174.78.64.1 to 174.78.71.254174.78.71.2552,046
74174.78.72.0/21174.78.72.1 to 174.78.79.254174.78.79.2552,046
75174.78.80.0/21174.78.80.1 to 174.78.87.254174.78.87.2552,046
76174.78.88.0/21174.78.88.1 to 174.78.95.254174.78.95.2552,046
77174.78.96.0/21174.78.96.1 to 174.78.103.254174.78.103.2552,046
78174.78.104.0/21174.78.104.1 to 174.78.111.254174.78.111.2552,046
79174.78.112.0/21174.78.112.1 to 174.78.119.254174.78.119.2552,046
80174.78.120.0/21174.78.120.1 to 174.78.127.254174.78.127.2552,046
81174.78.128.0/21174.78.128.1 to 174.78.135.254174.78.135.2552,046
82174.78.136.0/21174.78.136.1 to 174.78.143.254174.78.143.2552,046
83174.78.144.0/21174.78.144.1 to 174.78.151.254174.78.151.2552,046
84174.78.152.0/21174.78.152.1 to 174.78.159.254174.78.159.2552,046
85174.78.160.0/21174.78.160.1 to 174.78.167.254174.78.167.2552,046
86174.78.168.0/21174.78.168.1 to 174.78.175.254174.78.175.2552,046
87174.78.176.0/21174.78.176.1 to 174.78.183.254174.78.183.2552,046
88174.78.184.0/21174.78.184.1 to 174.78.191.254174.78.191.2552,046
89174.78.192.0/21174.78.192.1 to 174.78.199.254174.78.199.2552,046
90174.78.200.0/21174.78.200.1 to 174.78.207.254174.78.207.2552,046
91174.78.208.0/21174.78.208.1 to 174.78.215.254174.78.215.2552,046
92174.78.216.0/21174.78.216.1 to 174.78.223.254174.78.223.2552,046
93174.78.224.0/21174.78.224.1 to 174.78.231.254174.78.231.2552,046
94174.78.232.0/21174.78.232.1 to 174.78.239.254174.78.239.2552,046
95174.78.240.0/21174.78.240.1 to 174.78.247.254174.78.247.2552,046
96174.78.248.0/21174.78.248.1 to 174.78.255.254174.78.255.2552,046
97174.79.0.0/21174.79.0.1 to 174.79.7.254174.79.7.2552,046
98174.79.8.0/21174.79.8.1 to 174.79.15.254174.79.15.2552,046
99174.79.16.0/21174.79.16.1 to 174.79.23.254174.79.23.2552,046
100174.79.24.0/21174.79.24.1 to 174.79.31.254174.79.31.2552,046
101174.79.32.0/21174.79.32.1 to 174.79.39.254174.79.39.2552,046
102174.79.40.0/21174.79.40.1 to 174.79.47.254174.79.47.2552,046
103174.79.48.0/21174.79.48.1 to 174.79.55.254174.79.55.2552,046
104174.79.56.0/21174.79.56.1 to 174.79.63.254174.79.63.2552,046
105174.79.64.0/21174.79.64.1 to 174.79.71.254174.79.71.2552,046
106174.79.72.0/21174.79.72.1 to 174.79.79.254174.79.79.2552,046
107174.79.80.0/21174.79.80.1 to 174.79.87.254174.79.87.2552,046
108174.79.88.0/21174.79.88.1 to 174.79.95.254174.79.95.2552,046
109174.79.96.0/21174.79.96.1 to 174.79.103.254174.79.103.2552,046
110174.79.104.0/21174.79.104.1 to 174.79.111.254174.79.111.2552,046
111174.79.112.0/21174.79.112.1 to 174.79.119.254174.79.119.2552,046
112174.79.120.0/21174.79.120.1 to 174.79.127.254174.79.127.2552,046
113174.79.128.0/21174.79.128.1 to 174.79.135.254174.79.135.2552,046
114174.79.136.0/21174.79.136.1 to 174.79.143.254174.79.143.2552,046
115174.79.144.0/21174.79.144.1 to 174.79.151.254174.79.151.2552,046
116174.79.152.0/21174.79.152.1 to 174.79.159.254174.79.159.2552,046
117174.79.160.0/21174.79.160.1 to 174.79.167.254174.79.167.2552,046
118174.79.168.0/21174.79.168.1 to 174.79.175.254174.79.175.2552,046
119174.79.176.0/21174.79.176.1 to 174.79.183.254174.79.183.2552,046
120174.79.184.0/21174.79.184.1 to 174.79.191.254174.79.191.2552,046
121174.79.192.0/21174.79.192.1 to 174.79.199.254174.79.199.2552,046
122174.79.200.0/21174.79.200.1 to 174.79.207.254174.79.207.2552,046
123174.79.208.0/21174.79.208.1 to 174.79.215.254174.79.215.2552,046
124174.79.216.0/21174.79.216.1 to 174.79.223.254174.79.223.2552,046
125174.79.224.0/21174.79.224.1 to 174.79.231.254174.79.231.2552,046
126174.79.232.0/21174.79.232.1 to 174.79.239.254174.79.239.2552,046
127174.79.240.0/21174.79.240.1 to 174.79.247.254174.79.247.2552,046
128174.79.248.0/21174.79.248.1 to 174.79.255.254174.79.255.2552,046

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.