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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.

Network49.167.167.0/24
Usable hosts254
Subnet mask255.255.255.0
Addresses256
Network address
49.167.167.0
Broadcast address
49.167.167.255
First usable
49.167.167.1
Last usable
49.167.167.254
Usable hosts
254 (256 less the network and broadcast addresses)
Subnet mask
255.255.255.0
Wildcard mask
0.0.0.255 (Cisco ACLs, OSPF)
Prefix length
/24
Type
Public public
Old class
A (default /8)
As numbers
Hex 31A7A700 · Integer 833070848 to 833071103
Reverse DNS zone
167.167.49.in-addr.arpa
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address00110001.10100111.10100111..0000000049.167.167.0
Subnet mask11111111.11111111.11111111..00000000255.255.255.0
Network00110001.10100111.10100111..0000000049.167.167.0
Broadcast00110001.10100111.10100111..1111111149.167.167.255
Split into smaller subnets/31
/25 (2)/26 (4)/27 (8)/28 (16)/29 (32)/30 (64)/31 (128)/32 (256)

49.167.167.0/24 makes 128 subnets of /31.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
149.167.167.0/3149.167.167.0 to 49.167.167.1—2
249.167.167.2/3149.167.167.2 to 49.167.167.3—2
349.167.167.4/3149.167.167.4 to 49.167.167.5—2
449.167.167.6/3149.167.167.6 to 49.167.167.7—2
549.167.167.8/3149.167.167.8 to 49.167.167.9—2
649.167.167.10/3149.167.167.10 to 49.167.167.11—2
749.167.167.12/3149.167.167.12 to 49.167.167.13—2
849.167.167.14/3149.167.167.14 to 49.167.167.15—2
949.167.167.16/3149.167.167.16 to 49.167.167.17—2
1049.167.167.18/3149.167.167.18 to 49.167.167.19—2
1149.167.167.20/3149.167.167.20 to 49.167.167.21—2
1249.167.167.22/3149.167.167.22 to 49.167.167.23—2
1349.167.167.24/3149.167.167.24 to 49.167.167.25—2
1449.167.167.26/3149.167.167.26 to 49.167.167.27—2
1549.167.167.28/3149.167.167.28 to 49.167.167.29—2
1649.167.167.30/3149.167.167.30 to 49.167.167.31—2
1749.167.167.32/3149.167.167.32 to 49.167.167.33—2
1849.167.167.34/3149.167.167.34 to 49.167.167.35—2
1949.167.167.36/3149.167.167.36 to 49.167.167.37—2
2049.167.167.38/3149.167.167.38 to 49.167.167.39—2
2149.167.167.40/3149.167.167.40 to 49.167.167.41—2
2249.167.167.42/3149.167.167.42 to 49.167.167.43—2
2349.167.167.44/3149.167.167.44 to 49.167.167.45—2
2449.167.167.46/3149.167.167.46 to 49.167.167.47—2
2549.167.167.48/3149.167.167.48 to 49.167.167.49—2
2649.167.167.50/3149.167.167.50 to 49.167.167.51—2
2749.167.167.52/3149.167.167.52 to 49.167.167.53—2
2849.167.167.54/3149.167.167.54 to 49.167.167.55—2
2949.167.167.56/3149.167.167.56 to 49.167.167.57—2
3049.167.167.58/3149.167.167.58 to 49.167.167.59—2
3149.167.167.60/3149.167.167.60 to 49.167.167.61—2
3249.167.167.62/3149.167.167.62 to 49.167.167.63—2
3349.167.167.64/3149.167.167.64 to 49.167.167.65—2
3449.167.167.66/3149.167.167.66 to 49.167.167.67—2
3549.167.167.68/3149.167.167.68 to 49.167.167.69—2
3649.167.167.70/3149.167.167.70 to 49.167.167.71—2
3749.167.167.72/3149.167.167.72 to 49.167.167.73—2
3849.167.167.74/3149.167.167.74 to 49.167.167.75—2
3949.167.167.76/3149.167.167.76 to 49.167.167.77—2
4049.167.167.78/3149.167.167.78 to 49.167.167.79—2
4149.167.167.80/3149.167.167.80 to 49.167.167.81—2
4249.167.167.82/3149.167.167.82 to 49.167.167.83—2
4349.167.167.84/3149.167.167.84 to 49.167.167.85—2
4449.167.167.86/3149.167.167.86 to 49.167.167.87—2
4549.167.167.88/3149.167.167.88 to 49.167.167.89—2
4649.167.167.90/3149.167.167.90 to 49.167.167.91—2
4749.167.167.92/3149.167.167.92 to 49.167.167.93—2
4849.167.167.94/3149.167.167.94 to 49.167.167.95—2
4949.167.167.96/3149.167.167.96 to 49.167.167.97—2
5049.167.167.98/3149.167.167.98 to 49.167.167.99—2
5149.167.167.100/3149.167.167.100 to 49.167.167.101—2
5249.167.167.102/3149.167.167.102 to 49.167.167.103—2
5349.167.167.104/3149.167.167.104 to 49.167.167.105—2
5449.167.167.106/3149.167.167.106 to 49.167.167.107—2
5549.167.167.108/3149.167.167.108 to 49.167.167.109—2
5649.167.167.110/3149.167.167.110 to 49.167.167.111—2
5749.167.167.112/3149.167.167.112 to 49.167.167.113—2
5849.167.167.114/3149.167.167.114 to 49.167.167.115—2
5949.167.167.116/3149.167.167.116 to 49.167.167.117—2
6049.167.167.118/3149.167.167.118 to 49.167.167.119—2
6149.167.167.120/3149.167.167.120 to 49.167.167.121—2
6249.167.167.122/3149.167.167.122 to 49.167.167.123—2
6349.167.167.124/3149.167.167.124 to 49.167.167.125—2
6449.167.167.126/3149.167.167.126 to 49.167.167.127—2
6549.167.167.128/3149.167.167.128 to 49.167.167.129—2
6649.167.167.130/3149.167.167.130 to 49.167.167.131—2
6749.167.167.132/3149.167.167.132 to 49.167.167.133—2
6849.167.167.134/3149.167.167.134 to 49.167.167.135—2
6949.167.167.136/3149.167.167.136 to 49.167.167.137—2
7049.167.167.138/3149.167.167.138 to 49.167.167.139—2
7149.167.167.140/3149.167.167.140 to 49.167.167.141—2
7249.167.167.142/3149.167.167.142 to 49.167.167.143—2
7349.167.167.144/3149.167.167.144 to 49.167.167.145—2
7449.167.167.146/3149.167.167.146 to 49.167.167.147—2
7549.167.167.148/3149.167.167.148 to 49.167.167.149—2
7649.167.167.150/3149.167.167.150 to 49.167.167.151—2
7749.167.167.152/3149.167.167.152 to 49.167.167.153—2
7849.167.167.154/3149.167.167.154 to 49.167.167.155—2
7949.167.167.156/3149.167.167.156 to 49.167.167.157—2
8049.167.167.158/3149.167.167.158 to 49.167.167.159—2
8149.167.167.160/3149.167.167.160 to 49.167.167.161—2
8249.167.167.162/3149.167.167.162 to 49.167.167.163—2
8349.167.167.164/3149.167.167.164 to 49.167.167.165—2
8449.167.167.166/3149.167.167.166 to 49.167.167.167—2
8549.167.167.168/3149.167.167.168 to 49.167.167.169—2
8649.167.167.170/3149.167.167.170 to 49.167.167.171—2
8749.167.167.172/3149.167.167.172 to 49.167.167.173—2
8849.167.167.174/3149.167.167.174 to 49.167.167.175—2
8949.167.167.176/3149.167.167.176 to 49.167.167.177—2
9049.167.167.178/3149.167.167.178 to 49.167.167.179—2
9149.167.167.180/3149.167.167.180 to 49.167.167.181—2
9249.167.167.182/3149.167.167.182 to 49.167.167.183—2
9349.167.167.184/3149.167.167.184 to 49.167.167.185—2
9449.167.167.186/3149.167.167.186 to 49.167.167.187—2
9549.167.167.188/3149.167.167.188 to 49.167.167.189—2
9649.167.167.190/3149.167.167.190 to 49.167.167.191—2
9749.167.167.192/3149.167.167.192 to 49.167.167.193—2
9849.167.167.194/3149.167.167.194 to 49.167.167.195—2
9949.167.167.196/3149.167.167.196 to 49.167.167.197—2
10049.167.167.198/3149.167.167.198 to 49.167.167.199—2
10149.167.167.200/3149.167.167.200 to 49.167.167.201—2
10249.167.167.202/3149.167.167.202 to 49.167.167.203—2
10349.167.167.204/3149.167.167.204 to 49.167.167.205—2
10449.167.167.206/3149.167.167.206 to 49.167.167.207—2
10549.167.167.208/3149.167.167.208 to 49.167.167.209—2
10649.167.167.210/3149.167.167.210 to 49.167.167.211—2
10749.167.167.212/3149.167.167.212 to 49.167.167.213—2
10849.167.167.214/3149.167.167.214 to 49.167.167.215—2
10949.167.167.216/3149.167.167.216 to 49.167.167.217—2
11049.167.167.218/3149.167.167.218 to 49.167.167.219—2
11149.167.167.220/3149.167.167.220 to 49.167.167.221—2
11249.167.167.222/3149.167.167.222 to 49.167.167.223—2
11349.167.167.224/3149.167.167.224 to 49.167.167.225—2
11449.167.167.226/3149.167.167.226 to 49.167.167.227—2
11549.167.167.228/3149.167.167.228 to 49.167.167.229—2
11649.167.167.230/3149.167.167.230 to 49.167.167.231—2
11749.167.167.232/3149.167.167.232 to 49.167.167.233—2
11849.167.167.234/3149.167.167.234 to 49.167.167.235—2
11949.167.167.236/3149.167.167.236 to 49.167.167.237—2
12049.167.167.238/3149.167.167.238 to 49.167.167.239—2
12149.167.167.240/3149.167.167.240 to 49.167.167.241—2
12249.167.167.242/3149.167.167.242 to 49.167.167.243—2
12349.167.167.244/3149.167.167.244 to 49.167.167.245—2
12449.167.167.246/3149.167.167.246 to 49.167.167.247—2
12549.167.167.248/3149.167.167.248 to 49.167.167.249—2
12649.167.167.250/3149.167.167.250 to 49.167.167.251—2
12749.167.167.252/3149.167.167.252 to 49.167.167.253—2
12849.167.167.254/3149.167.167.254 to 49.167.167.255—2

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.