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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.

Network78.0.0.0/7
Usable hosts33,554,430
Subnet mask254.0.0.0
Addresses33,554,432
Network address
78.0.0.0
Broadcast address
79.255.255.255
First usable
78.0.0.1
Last usable
79.255.255.254
Usable hosts
33,554,430 (33,554,432 less the network and broadcast addresses)
Subnet mask
254.0.0.0
Wildcard mask
1.255.255.255 (Cisco ACLs, OSPF)
Prefix length
/7
Type
Public public
Old class
A (default /8)
As numbers
Hex 4E000000 · Integer 1308622848 to 1342177279
Reverse DNS zones
78.in-addr.arpa
79.in-addr.arpa
/7 is not on a 8-bit boundary, so it takes 2 /8 zones.
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address01001110.00000000.00000000.0000000078.0.0.0
Subnet mask11111110.00000000.00000000.00000000254.0.0.0
Network01001110.00000000.00000000.0000000078.0.0.0
Broadcast01001111.11111111.11111111.1111111179.255.255.255
Split into smaller subnets/14

78.0.0.0/7 makes 128 subnets of /14.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
178.0.0.0/1478.0.0.1 to 78.3.255.25478.3.255.255262,142
278.4.0.0/1478.4.0.1 to 78.7.255.25478.7.255.255262,142
378.8.0.0/1478.8.0.1 to 78.11.255.25478.11.255.255262,142
478.12.0.0/1478.12.0.1 to 78.15.255.25478.15.255.255262,142
578.16.0.0/1478.16.0.1 to 78.19.255.25478.19.255.255262,142
678.20.0.0/1478.20.0.1 to 78.23.255.25478.23.255.255262,142
778.24.0.0/1478.24.0.1 to 78.27.255.25478.27.255.255262,142
878.28.0.0/1478.28.0.1 to 78.31.255.25478.31.255.255262,142
978.32.0.0/1478.32.0.1 to 78.35.255.25478.35.255.255262,142
1078.36.0.0/1478.36.0.1 to 78.39.255.25478.39.255.255262,142
1178.40.0.0/1478.40.0.1 to 78.43.255.25478.43.255.255262,142
1278.44.0.0/1478.44.0.1 to 78.47.255.25478.47.255.255262,142
1378.48.0.0/1478.48.0.1 to 78.51.255.25478.51.255.255262,142
1478.52.0.0/1478.52.0.1 to 78.55.255.25478.55.255.255262,142
1578.56.0.0/1478.56.0.1 to 78.59.255.25478.59.255.255262,142
1678.60.0.0/1478.60.0.1 to 78.63.255.25478.63.255.255262,142
1778.64.0.0/1478.64.0.1 to 78.67.255.25478.67.255.255262,142
1878.68.0.0/1478.68.0.1 to 78.71.255.25478.71.255.255262,142
1978.72.0.0/1478.72.0.1 to 78.75.255.25478.75.255.255262,142
2078.76.0.0/1478.76.0.1 to 78.79.255.25478.79.255.255262,142
2178.80.0.0/1478.80.0.1 to 78.83.255.25478.83.255.255262,142
2278.84.0.0/1478.84.0.1 to 78.87.255.25478.87.255.255262,142
2378.88.0.0/1478.88.0.1 to 78.91.255.25478.91.255.255262,142
2478.92.0.0/1478.92.0.1 to 78.95.255.25478.95.255.255262,142
2578.96.0.0/1478.96.0.1 to 78.99.255.25478.99.255.255262,142
2678.100.0.0/1478.100.0.1 to 78.103.255.25478.103.255.255262,142
2778.104.0.0/1478.104.0.1 to 78.107.255.25478.107.255.255262,142
2878.108.0.0/1478.108.0.1 to 78.111.255.25478.111.255.255262,142
2978.112.0.0/1478.112.0.1 to 78.115.255.25478.115.255.255262,142
3078.116.0.0/1478.116.0.1 to 78.119.255.25478.119.255.255262,142
3178.120.0.0/1478.120.0.1 to 78.123.255.25478.123.255.255262,142
3278.124.0.0/1478.124.0.1 to 78.127.255.25478.127.255.255262,142
3378.128.0.0/1478.128.0.1 to 78.131.255.25478.131.255.255262,142
3478.132.0.0/1478.132.0.1 to 78.135.255.25478.135.255.255262,142
3578.136.0.0/1478.136.0.1 to 78.139.255.25478.139.255.255262,142
3678.140.0.0/1478.140.0.1 to 78.143.255.25478.143.255.255262,142
3778.144.0.0/1478.144.0.1 to 78.147.255.25478.147.255.255262,142
3878.148.0.0/1478.148.0.1 to 78.151.255.25478.151.255.255262,142
3978.152.0.0/1478.152.0.1 to 78.155.255.25478.155.255.255262,142
4078.156.0.0/1478.156.0.1 to 78.159.255.25478.159.255.255262,142
4178.160.0.0/1478.160.0.1 to 78.163.255.25478.163.255.255262,142
4278.164.0.0/1478.164.0.1 to 78.167.255.25478.167.255.255262,142
4378.168.0.0/1478.168.0.1 to 78.171.255.25478.171.255.255262,142
4478.172.0.0/1478.172.0.1 to 78.175.255.25478.175.255.255262,142
4578.176.0.0/1478.176.0.1 to 78.179.255.25478.179.255.255262,142
4678.180.0.0/1478.180.0.1 to 78.183.255.25478.183.255.255262,142
4778.184.0.0/1478.184.0.1 to 78.187.255.25478.187.255.255262,142
4878.188.0.0/1478.188.0.1 to 78.191.255.25478.191.255.255262,142
4978.192.0.0/1478.192.0.1 to 78.195.255.25478.195.255.255262,142
5078.196.0.0/1478.196.0.1 to 78.199.255.25478.199.255.255262,142
5178.200.0.0/1478.200.0.1 to 78.203.255.25478.203.255.255262,142
5278.204.0.0/1478.204.0.1 to 78.207.255.25478.207.255.255262,142
5378.208.0.0/1478.208.0.1 to 78.211.255.25478.211.255.255262,142
5478.212.0.0/1478.212.0.1 to 78.215.255.25478.215.255.255262,142
5578.216.0.0/1478.216.0.1 to 78.219.255.25478.219.255.255262,142
5678.220.0.0/1478.220.0.1 to 78.223.255.25478.223.255.255262,142
5778.224.0.0/1478.224.0.1 to 78.227.255.25478.227.255.255262,142
5878.228.0.0/1478.228.0.1 to 78.231.255.25478.231.255.255262,142
5978.232.0.0/1478.232.0.1 to 78.235.255.25478.235.255.255262,142
6078.236.0.0/1478.236.0.1 to 78.239.255.25478.239.255.255262,142
6178.240.0.0/1478.240.0.1 to 78.243.255.25478.243.255.255262,142
6278.244.0.0/1478.244.0.1 to 78.247.255.25478.247.255.255262,142
6378.248.0.0/1478.248.0.1 to 78.251.255.25478.251.255.255262,142
6478.252.0.0/1478.252.0.1 to 78.255.255.25478.255.255.255262,142
6579.0.0.0/1479.0.0.1 to 79.3.255.25479.3.255.255262,142
6679.4.0.0/1479.4.0.1 to 79.7.255.25479.7.255.255262,142
6779.8.0.0/1479.8.0.1 to 79.11.255.25479.11.255.255262,142
6879.12.0.0/1479.12.0.1 to 79.15.255.25479.15.255.255262,142
6979.16.0.0/1479.16.0.1 to 79.19.255.25479.19.255.255262,142
7079.20.0.0/1479.20.0.1 to 79.23.255.25479.23.255.255262,142
7179.24.0.0/1479.24.0.1 to 79.27.255.25479.27.255.255262,142
7279.28.0.0/1479.28.0.1 to 79.31.255.25479.31.255.255262,142
7379.32.0.0/1479.32.0.1 to 79.35.255.25479.35.255.255262,142
7479.36.0.0/1479.36.0.1 to 79.39.255.25479.39.255.255262,142
7579.40.0.0/1479.40.0.1 to 79.43.255.25479.43.255.255262,142
7679.44.0.0/1479.44.0.1 to 79.47.255.25479.47.255.255262,142
7779.48.0.0/1479.48.0.1 to 79.51.255.25479.51.255.255262,142
7879.52.0.0/1479.52.0.1 to 79.55.255.25479.55.255.255262,142
7979.56.0.0/1479.56.0.1 to 79.59.255.25479.59.255.255262,142
8079.60.0.0/1479.60.0.1 to 79.63.255.25479.63.255.255262,142
8179.64.0.0/1479.64.0.1 to 79.67.255.25479.67.255.255262,142
8279.68.0.0/1479.68.0.1 to 79.71.255.25479.71.255.255262,142
8379.72.0.0/1479.72.0.1 to 79.75.255.25479.75.255.255262,142
8479.76.0.0/1479.76.0.1 to 79.79.255.25479.79.255.255262,142
8579.80.0.0/1479.80.0.1 to 79.83.255.25479.83.255.255262,142
8679.84.0.0/1479.84.0.1 to 79.87.255.25479.87.255.255262,142
8779.88.0.0/1479.88.0.1 to 79.91.255.25479.91.255.255262,142
8879.92.0.0/1479.92.0.1 to 79.95.255.25479.95.255.255262,142
8979.96.0.0/1479.96.0.1 to 79.99.255.25479.99.255.255262,142
9079.100.0.0/1479.100.0.1 to 79.103.255.25479.103.255.255262,142
9179.104.0.0/1479.104.0.1 to 79.107.255.25479.107.255.255262,142
9279.108.0.0/1479.108.0.1 to 79.111.255.25479.111.255.255262,142
9379.112.0.0/1479.112.0.1 to 79.115.255.25479.115.255.255262,142
9479.116.0.0/1479.116.0.1 to 79.119.255.25479.119.255.255262,142
9579.120.0.0/1479.120.0.1 to 79.123.255.25479.123.255.255262,142
9679.124.0.0/1479.124.0.1 to 79.127.255.25479.127.255.255262,142
9779.128.0.0/1479.128.0.1 to 79.131.255.25479.131.255.255262,142
9879.132.0.0/1479.132.0.1 to 79.135.255.25479.135.255.255262,142
9979.136.0.0/1479.136.0.1 to 79.139.255.25479.139.255.255262,142
10079.140.0.0/1479.140.0.1 to 79.143.255.25479.143.255.255262,142
10179.144.0.0/1479.144.0.1 to 79.147.255.25479.147.255.255262,142
10279.148.0.0/1479.148.0.1 to 79.151.255.25479.151.255.255262,142
10379.152.0.0/1479.152.0.1 to 79.155.255.25479.155.255.255262,142
10479.156.0.0/1479.156.0.1 to 79.159.255.25479.159.255.255262,142
10579.160.0.0/1479.160.0.1 to 79.163.255.25479.163.255.255262,142
10679.164.0.0/1479.164.0.1 to 79.167.255.25479.167.255.255262,142
10779.168.0.0/1479.168.0.1 to 79.171.255.25479.171.255.255262,142
10879.172.0.0/1479.172.0.1 to 79.175.255.25479.175.255.255262,142
10979.176.0.0/1479.176.0.1 to 79.179.255.25479.179.255.255262,142
11079.180.0.0/1479.180.0.1 to 79.183.255.25479.183.255.255262,142
11179.184.0.0/1479.184.0.1 to 79.187.255.25479.187.255.255262,142
11279.188.0.0/1479.188.0.1 to 79.191.255.25479.191.255.255262,142
11379.192.0.0/1479.192.0.1 to 79.195.255.25479.195.255.255262,142
11479.196.0.0/1479.196.0.1 to 79.199.255.25479.199.255.255262,142
11579.200.0.0/1479.200.0.1 to 79.203.255.25479.203.255.255262,142
11679.204.0.0/1479.204.0.1 to 79.207.255.25479.207.255.255262,142
11779.208.0.0/1479.208.0.1 to 79.211.255.25479.211.255.255262,142
11879.212.0.0/1479.212.0.1 to 79.215.255.25479.215.255.255262,142
11979.216.0.0/1479.216.0.1 to 79.219.255.25479.219.255.255262,142
12079.220.0.0/1479.220.0.1 to 79.223.255.25479.223.255.255262,142
12179.224.0.0/1479.224.0.1 to 79.227.255.25479.227.255.255262,142
12279.228.0.0/1479.228.0.1 to 79.231.255.25479.231.255.255262,142
12379.232.0.0/1479.232.0.1 to 79.235.255.25479.235.255.255262,142
12479.236.0.0/1479.236.0.1 to 79.239.255.25479.239.255.255262,142
12579.240.0.0/1479.240.0.1 to 79.243.255.25479.243.255.255262,142
12679.244.0.0/1479.244.0.1 to 79.247.255.25479.247.255.255262,142
12779.248.0.0/1479.248.0.1 to 79.251.255.25479.251.255.255262,142
12879.252.0.0/1479.252.0.1 to 79.255.255.25479.255.255.255262,142

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