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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.

Network71.3.78.0/24
Usable hosts254
Subnet mask255.255.255.0
Addresses256
Network address
71.3.78.0
Broadcast address
71.3.78.255
First usable
71.3.78.1
Last usable
71.3.78.254
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 47034E00 · Integer 1191398912 to 1191399167
Reverse DNS zone
78.3.71.in-addr.arpa
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address01000111.00000011.01001110..0000000071.3.78.0
Subnet mask11111111.11111111.11111111..00000000255.255.255.0
Network01000111.00000011.01001110..0000000071.3.78.0
Broadcast01000111.00000011.01001110..1111111171.3.78.255
Split into smaller subnets/30

71.3.78.0/24 makes 64 subnets of /30.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
171.3.78.0/3071.3.78.1 to 71.3.78.271.3.78.32
271.3.78.4/3071.3.78.5 to 71.3.78.671.3.78.72
371.3.78.8/3071.3.78.9 to 71.3.78.1071.3.78.112
471.3.78.12/3071.3.78.13 to 71.3.78.1471.3.78.152
571.3.78.16/3071.3.78.17 to 71.3.78.1871.3.78.192
671.3.78.20/3071.3.78.21 to 71.3.78.2271.3.78.232
771.3.78.24/3071.3.78.25 to 71.3.78.2671.3.78.272
871.3.78.28/3071.3.78.29 to 71.3.78.3071.3.78.312
971.3.78.32/3071.3.78.33 to 71.3.78.3471.3.78.352
1071.3.78.36/3071.3.78.37 to 71.3.78.3871.3.78.392
1171.3.78.40/3071.3.78.41 to 71.3.78.4271.3.78.432
1271.3.78.44/3071.3.78.45 to 71.3.78.4671.3.78.472
1371.3.78.48/3071.3.78.49 to 71.3.78.5071.3.78.512
1471.3.78.52/3071.3.78.53 to 71.3.78.5471.3.78.552
1571.3.78.56/3071.3.78.57 to 71.3.78.5871.3.78.592
1671.3.78.60/3071.3.78.61 to 71.3.78.6271.3.78.632
1771.3.78.64/3071.3.78.65 to 71.3.78.6671.3.78.672
1871.3.78.68/3071.3.78.69 to 71.3.78.7071.3.78.712
1971.3.78.72/3071.3.78.73 to 71.3.78.7471.3.78.752
2071.3.78.76/3071.3.78.77 to 71.3.78.7871.3.78.792
2171.3.78.80/3071.3.78.81 to 71.3.78.8271.3.78.832
2271.3.78.84/3071.3.78.85 to 71.3.78.8671.3.78.872
2371.3.78.88/3071.3.78.89 to 71.3.78.9071.3.78.912
2471.3.78.92/3071.3.78.93 to 71.3.78.9471.3.78.952
2571.3.78.96/3071.3.78.97 to 71.3.78.9871.3.78.992
2671.3.78.100/3071.3.78.101 to 71.3.78.10271.3.78.1032
2771.3.78.104/3071.3.78.105 to 71.3.78.10671.3.78.1072
2871.3.78.108/3071.3.78.109 to 71.3.78.11071.3.78.1112
2971.3.78.112/3071.3.78.113 to 71.3.78.11471.3.78.1152
3071.3.78.116/3071.3.78.117 to 71.3.78.11871.3.78.1192
3171.3.78.120/3071.3.78.121 to 71.3.78.12271.3.78.1232
3271.3.78.124/3071.3.78.125 to 71.3.78.12671.3.78.1272
3371.3.78.128/3071.3.78.129 to 71.3.78.13071.3.78.1312
3471.3.78.132/3071.3.78.133 to 71.3.78.13471.3.78.1352
3571.3.78.136/3071.3.78.137 to 71.3.78.13871.3.78.1392
3671.3.78.140/3071.3.78.141 to 71.3.78.14271.3.78.1432
3771.3.78.144/3071.3.78.145 to 71.3.78.14671.3.78.1472
3871.3.78.148/3071.3.78.149 to 71.3.78.15071.3.78.1512
3971.3.78.152/3071.3.78.153 to 71.3.78.15471.3.78.1552
4071.3.78.156/3071.3.78.157 to 71.3.78.15871.3.78.1592
4171.3.78.160/3071.3.78.161 to 71.3.78.16271.3.78.1632
4271.3.78.164/3071.3.78.165 to 71.3.78.16671.3.78.1672
4371.3.78.168/3071.3.78.169 to 71.3.78.17071.3.78.1712
4471.3.78.172/3071.3.78.173 to 71.3.78.17471.3.78.1752
4571.3.78.176/3071.3.78.177 to 71.3.78.17871.3.78.1792
4671.3.78.180/3071.3.78.181 to 71.3.78.18271.3.78.1832
4771.3.78.184/3071.3.78.185 to 71.3.78.18671.3.78.1872
4871.3.78.188/3071.3.78.189 to 71.3.78.19071.3.78.1912
4971.3.78.192/3071.3.78.193 to 71.3.78.19471.3.78.1952
5071.3.78.196/3071.3.78.197 to 71.3.78.19871.3.78.1992
5171.3.78.200/3071.3.78.201 to 71.3.78.20271.3.78.2032
5271.3.78.204/3071.3.78.205 to 71.3.78.20671.3.78.2072
5371.3.78.208/3071.3.78.209 to 71.3.78.21071.3.78.2112
5471.3.78.212/3071.3.78.213 to 71.3.78.21471.3.78.2152
5571.3.78.216/3071.3.78.217 to 71.3.78.21871.3.78.2192
5671.3.78.220/3071.3.78.221 to 71.3.78.22271.3.78.2232
5771.3.78.224/3071.3.78.225 to 71.3.78.22671.3.78.2272
5871.3.78.228/3071.3.78.229 to 71.3.78.23071.3.78.2312
5971.3.78.232/3071.3.78.233 to 71.3.78.23471.3.78.2352
6071.3.78.236/3071.3.78.237 to 71.3.78.23871.3.78.2392
6171.3.78.240/3071.3.78.241 to 71.3.78.24271.3.78.2432
6271.3.78.244/3071.3.78.245 to 71.3.78.24671.3.78.2472
6371.3.78.248/3071.3.78.249 to 71.3.78.25071.3.78.2512
6471.3.78.252/3071.3.78.253 to 71.3.78.25471.3.78.2552

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