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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.

Network14.0.76.0/24
Usable hosts254
Subnet mask255.255.255.0
Addresses256
Network address
14.0.76.0
Broadcast address
14.0.76.255
First usable
14.0.76.1
Last usable
14.0.76.254
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 0E004C00 · Integer 234900480 to 234900735
Reverse DNS zone
76.0.14.in-addr.arpa
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address00001110.00000000.01001100..0000000014.0.76.0
Subnet mask11111111.11111111.11111111..00000000255.255.255.0
Network00001110.00000000.01001100..0000000014.0.76.0
Broadcast00001110.00000000.01001100..1111111114.0.76.255
Split into smaller subnets/30
/25 (2)/26 (4)/27 (8)/28 (16)/29 (32)/30 (64)/31 (128)/32 (256)

14.0.76.0/24 makes 64 subnets of /30.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
114.0.76.0/3014.0.76.1 to 14.0.76.214.0.76.32
214.0.76.4/3014.0.76.5 to 14.0.76.614.0.76.72
314.0.76.8/3014.0.76.9 to 14.0.76.1014.0.76.112
414.0.76.12/3014.0.76.13 to 14.0.76.1414.0.76.152
514.0.76.16/3014.0.76.17 to 14.0.76.1814.0.76.192
614.0.76.20/3014.0.76.21 to 14.0.76.2214.0.76.232
714.0.76.24/3014.0.76.25 to 14.0.76.2614.0.76.272
814.0.76.28/3014.0.76.29 to 14.0.76.3014.0.76.312
914.0.76.32/3014.0.76.33 to 14.0.76.3414.0.76.352
1014.0.76.36/3014.0.76.37 to 14.0.76.3814.0.76.392
1114.0.76.40/3014.0.76.41 to 14.0.76.4214.0.76.432
1214.0.76.44/3014.0.76.45 to 14.0.76.4614.0.76.472
1314.0.76.48/3014.0.76.49 to 14.0.76.5014.0.76.512
1414.0.76.52/3014.0.76.53 to 14.0.76.5414.0.76.552
1514.0.76.56/3014.0.76.57 to 14.0.76.5814.0.76.592
1614.0.76.60/3014.0.76.61 to 14.0.76.6214.0.76.632
1714.0.76.64/3014.0.76.65 to 14.0.76.6614.0.76.672
1814.0.76.68/3014.0.76.69 to 14.0.76.7014.0.76.712
1914.0.76.72/3014.0.76.73 to 14.0.76.7414.0.76.752
2014.0.76.76/3014.0.76.77 to 14.0.76.7814.0.76.792
2114.0.76.80/3014.0.76.81 to 14.0.76.8214.0.76.832
2214.0.76.84/3014.0.76.85 to 14.0.76.8614.0.76.872
2314.0.76.88/3014.0.76.89 to 14.0.76.9014.0.76.912
2414.0.76.92/3014.0.76.93 to 14.0.76.9414.0.76.952
2514.0.76.96/3014.0.76.97 to 14.0.76.9814.0.76.992
2614.0.76.100/3014.0.76.101 to 14.0.76.10214.0.76.1032
2714.0.76.104/3014.0.76.105 to 14.0.76.10614.0.76.1072
2814.0.76.108/3014.0.76.109 to 14.0.76.11014.0.76.1112
2914.0.76.112/3014.0.76.113 to 14.0.76.11414.0.76.1152
3014.0.76.116/3014.0.76.117 to 14.0.76.11814.0.76.1192
3114.0.76.120/3014.0.76.121 to 14.0.76.12214.0.76.1232
3214.0.76.124/3014.0.76.125 to 14.0.76.12614.0.76.1272
3314.0.76.128/3014.0.76.129 to 14.0.76.13014.0.76.1312
3414.0.76.132/3014.0.76.133 to 14.0.76.13414.0.76.1352
3514.0.76.136/3014.0.76.137 to 14.0.76.13814.0.76.1392
3614.0.76.140/3014.0.76.141 to 14.0.76.14214.0.76.1432
3714.0.76.144/3014.0.76.145 to 14.0.76.14614.0.76.1472
3814.0.76.148/3014.0.76.149 to 14.0.76.15014.0.76.1512
3914.0.76.152/3014.0.76.153 to 14.0.76.15414.0.76.1552
4014.0.76.156/3014.0.76.157 to 14.0.76.15814.0.76.1592
4114.0.76.160/3014.0.76.161 to 14.0.76.16214.0.76.1632
4214.0.76.164/3014.0.76.165 to 14.0.76.16614.0.76.1672
4314.0.76.168/3014.0.76.169 to 14.0.76.17014.0.76.1712
4414.0.76.172/3014.0.76.173 to 14.0.76.17414.0.76.1752
4514.0.76.176/3014.0.76.177 to 14.0.76.17814.0.76.1792
4614.0.76.180/3014.0.76.181 to 14.0.76.18214.0.76.1832
4714.0.76.184/3014.0.76.185 to 14.0.76.18614.0.76.1872
4814.0.76.188/3014.0.76.189 to 14.0.76.19014.0.76.1912
4914.0.76.192/3014.0.76.193 to 14.0.76.19414.0.76.1952
5014.0.76.196/3014.0.76.197 to 14.0.76.19814.0.76.1992
5114.0.76.200/3014.0.76.201 to 14.0.76.20214.0.76.2032
5214.0.76.204/3014.0.76.205 to 14.0.76.20614.0.76.2072
5314.0.76.208/3014.0.76.209 to 14.0.76.21014.0.76.2112
5414.0.76.212/3014.0.76.213 to 14.0.76.21414.0.76.2152
5514.0.76.216/3014.0.76.217 to 14.0.76.21814.0.76.2192
5614.0.76.220/3014.0.76.221 to 14.0.76.22214.0.76.2232
5714.0.76.224/3014.0.76.225 to 14.0.76.22614.0.76.2272
5814.0.76.228/3014.0.76.229 to 14.0.76.23014.0.76.2312
5914.0.76.232/3014.0.76.233 to 14.0.76.23414.0.76.2352
6014.0.76.236/3014.0.76.237 to 14.0.76.23814.0.76.2392
6114.0.76.240/3014.0.76.241 to 14.0.76.24214.0.76.2432
6214.0.76.244/3014.0.76.245 to 14.0.76.24614.0.76.2472
6314.0.76.248/3014.0.76.249 to 14.0.76.25014.0.76.2512
6414.0.76.252/3014.0.76.253 to 14.0.76.25414.0.76.2552

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.