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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.

Network78.78.0.0/17
Usable hosts32,766
Subnet mask255.255.128.0
Addresses32,768
Network address
78.78.0.0
Broadcast address
78.78.127.255
First usable
78.78.0.1
Last usable
78.78.127.254
Usable hosts
32,766 (32,768 less the network and broadcast addresses)
Subnet mask
255.255.128.0
Wildcard mask
0.0.127.255 (Cisco ACLs, OSPF)
Prefix length
/17
Type
Public public
Old class
A (default /8)
As numbers
Hex 4E4E0000 · Integer 1313734656 to 1313767423
Reverse DNS zones
0.78.78.in-addr.arpa
1.78.78.in-addr.arpa
2.78.78.in-addr.arpa
3.78.78.in-addr.arpa
4.78.78.in-addr.arpa
5.78.78.in-addr.arpa
6.78.78.in-addr.arpa
7.78.78.in-addr.arpa
8.78.78.in-addr.arpa
9.78.78.in-addr.arpa
10.78.78.in-addr.arpa
11.78.78.in-addr.arpa
12.78.78.in-addr.arpa
13.78.78.in-addr.arpa
14.78.78.in-addr.arpa
15.78.78.in-addr.arpa
and 112 more
/17 is not on a 8-bit boundary, so it takes 128 /24 zones.
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address01001110.01001110.00000000.0000000078.78.0.0
Subnet mask11111111.11111111.10000000.00000000255.255.128.0
Network01001110.01001110.00000000.0000000078.78.0.0
Broadcast01001110.01001110.01111111.1111111178.78.127.255
Split into smaller subnets/24

78.78.0.0/17 makes 128 subnets of /24.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
178.78.0.0/2478.78.0.1 to 78.78.0.25478.78.0.255254
278.78.1.0/2478.78.1.1 to 78.78.1.25478.78.1.255254
378.78.2.0/2478.78.2.1 to 78.78.2.25478.78.2.255254
478.78.3.0/2478.78.3.1 to 78.78.3.25478.78.3.255254
578.78.4.0/2478.78.4.1 to 78.78.4.25478.78.4.255254
678.78.5.0/2478.78.5.1 to 78.78.5.25478.78.5.255254
778.78.6.0/2478.78.6.1 to 78.78.6.25478.78.6.255254
878.78.7.0/2478.78.7.1 to 78.78.7.25478.78.7.255254
978.78.8.0/2478.78.8.1 to 78.78.8.25478.78.8.255254
1078.78.9.0/2478.78.9.1 to 78.78.9.25478.78.9.255254
1178.78.10.0/2478.78.10.1 to 78.78.10.25478.78.10.255254
1278.78.11.0/2478.78.11.1 to 78.78.11.25478.78.11.255254
1378.78.12.0/2478.78.12.1 to 78.78.12.25478.78.12.255254
1478.78.13.0/2478.78.13.1 to 78.78.13.25478.78.13.255254
1578.78.14.0/2478.78.14.1 to 78.78.14.25478.78.14.255254
1678.78.15.0/2478.78.15.1 to 78.78.15.25478.78.15.255254
1778.78.16.0/2478.78.16.1 to 78.78.16.25478.78.16.255254
1878.78.17.0/2478.78.17.1 to 78.78.17.25478.78.17.255254
1978.78.18.0/2478.78.18.1 to 78.78.18.25478.78.18.255254
2078.78.19.0/2478.78.19.1 to 78.78.19.25478.78.19.255254
2178.78.20.0/2478.78.20.1 to 78.78.20.25478.78.20.255254
2278.78.21.0/2478.78.21.1 to 78.78.21.25478.78.21.255254
2378.78.22.0/2478.78.22.1 to 78.78.22.25478.78.22.255254
2478.78.23.0/2478.78.23.1 to 78.78.23.25478.78.23.255254
2578.78.24.0/2478.78.24.1 to 78.78.24.25478.78.24.255254
2678.78.25.0/2478.78.25.1 to 78.78.25.25478.78.25.255254
2778.78.26.0/2478.78.26.1 to 78.78.26.25478.78.26.255254
2878.78.27.0/2478.78.27.1 to 78.78.27.25478.78.27.255254
2978.78.28.0/2478.78.28.1 to 78.78.28.25478.78.28.255254
3078.78.29.0/2478.78.29.1 to 78.78.29.25478.78.29.255254
3178.78.30.0/2478.78.30.1 to 78.78.30.25478.78.30.255254
3278.78.31.0/2478.78.31.1 to 78.78.31.25478.78.31.255254
3378.78.32.0/2478.78.32.1 to 78.78.32.25478.78.32.255254
3478.78.33.0/2478.78.33.1 to 78.78.33.25478.78.33.255254
3578.78.34.0/2478.78.34.1 to 78.78.34.25478.78.34.255254
3678.78.35.0/2478.78.35.1 to 78.78.35.25478.78.35.255254
3778.78.36.0/2478.78.36.1 to 78.78.36.25478.78.36.255254
3878.78.37.0/2478.78.37.1 to 78.78.37.25478.78.37.255254
3978.78.38.0/2478.78.38.1 to 78.78.38.25478.78.38.255254
4078.78.39.0/2478.78.39.1 to 78.78.39.25478.78.39.255254
4178.78.40.0/2478.78.40.1 to 78.78.40.25478.78.40.255254
4278.78.41.0/2478.78.41.1 to 78.78.41.25478.78.41.255254
4378.78.42.0/2478.78.42.1 to 78.78.42.25478.78.42.255254
4478.78.43.0/2478.78.43.1 to 78.78.43.25478.78.43.255254
4578.78.44.0/2478.78.44.1 to 78.78.44.25478.78.44.255254
4678.78.45.0/2478.78.45.1 to 78.78.45.25478.78.45.255254
4778.78.46.0/2478.78.46.1 to 78.78.46.25478.78.46.255254
4878.78.47.0/2478.78.47.1 to 78.78.47.25478.78.47.255254
4978.78.48.0/2478.78.48.1 to 78.78.48.25478.78.48.255254
5078.78.49.0/2478.78.49.1 to 78.78.49.25478.78.49.255254
5178.78.50.0/2478.78.50.1 to 78.78.50.25478.78.50.255254
5278.78.51.0/2478.78.51.1 to 78.78.51.25478.78.51.255254
5378.78.52.0/2478.78.52.1 to 78.78.52.25478.78.52.255254
5478.78.53.0/2478.78.53.1 to 78.78.53.25478.78.53.255254
5578.78.54.0/2478.78.54.1 to 78.78.54.25478.78.54.255254
5678.78.55.0/2478.78.55.1 to 78.78.55.25478.78.55.255254
5778.78.56.0/2478.78.56.1 to 78.78.56.25478.78.56.255254
5878.78.57.0/2478.78.57.1 to 78.78.57.25478.78.57.255254
5978.78.58.0/2478.78.58.1 to 78.78.58.25478.78.58.255254
6078.78.59.0/2478.78.59.1 to 78.78.59.25478.78.59.255254
6178.78.60.0/2478.78.60.1 to 78.78.60.25478.78.60.255254
6278.78.61.0/2478.78.61.1 to 78.78.61.25478.78.61.255254
6378.78.62.0/2478.78.62.1 to 78.78.62.25478.78.62.255254
6478.78.63.0/2478.78.63.1 to 78.78.63.25478.78.63.255254
6578.78.64.0/2478.78.64.1 to 78.78.64.25478.78.64.255254
6678.78.65.0/2478.78.65.1 to 78.78.65.25478.78.65.255254
6778.78.66.0/2478.78.66.1 to 78.78.66.25478.78.66.255254
6878.78.67.0/2478.78.67.1 to 78.78.67.25478.78.67.255254
6978.78.68.0/2478.78.68.1 to 78.78.68.25478.78.68.255254
7078.78.69.0/2478.78.69.1 to 78.78.69.25478.78.69.255254
7178.78.70.0/2478.78.70.1 to 78.78.70.25478.78.70.255254
7278.78.71.0/2478.78.71.1 to 78.78.71.25478.78.71.255254
7378.78.72.0/2478.78.72.1 to 78.78.72.25478.78.72.255254
7478.78.73.0/2478.78.73.1 to 78.78.73.25478.78.73.255254
7578.78.74.0/2478.78.74.1 to 78.78.74.25478.78.74.255254
7678.78.75.0/2478.78.75.1 to 78.78.75.25478.78.75.255254
7778.78.76.0/2478.78.76.1 to 78.78.76.25478.78.76.255254
7878.78.77.0/2478.78.77.1 to 78.78.77.25478.78.77.255254
7978.78.78.0/2478.78.78.1 to 78.78.78.25478.78.78.255254
8078.78.79.0/2478.78.79.1 to 78.78.79.25478.78.79.255254
8178.78.80.0/2478.78.80.1 to 78.78.80.25478.78.80.255254
8278.78.81.0/2478.78.81.1 to 78.78.81.25478.78.81.255254
8378.78.82.0/2478.78.82.1 to 78.78.82.25478.78.82.255254
8478.78.83.0/2478.78.83.1 to 78.78.83.25478.78.83.255254
8578.78.84.0/2478.78.84.1 to 78.78.84.25478.78.84.255254
8678.78.85.0/2478.78.85.1 to 78.78.85.25478.78.85.255254
8778.78.86.0/2478.78.86.1 to 78.78.86.25478.78.86.255254
8878.78.87.0/2478.78.87.1 to 78.78.87.25478.78.87.255254
8978.78.88.0/2478.78.88.1 to 78.78.88.25478.78.88.255254
9078.78.89.0/2478.78.89.1 to 78.78.89.25478.78.89.255254
9178.78.90.0/2478.78.90.1 to 78.78.90.25478.78.90.255254
9278.78.91.0/2478.78.91.1 to 78.78.91.25478.78.91.255254
9378.78.92.0/2478.78.92.1 to 78.78.92.25478.78.92.255254
9478.78.93.0/2478.78.93.1 to 78.78.93.25478.78.93.255254
9578.78.94.0/2478.78.94.1 to 78.78.94.25478.78.94.255254
9678.78.95.0/2478.78.95.1 to 78.78.95.25478.78.95.255254
9778.78.96.0/2478.78.96.1 to 78.78.96.25478.78.96.255254
9878.78.97.0/2478.78.97.1 to 78.78.97.25478.78.97.255254
9978.78.98.0/2478.78.98.1 to 78.78.98.25478.78.98.255254
10078.78.99.0/2478.78.99.1 to 78.78.99.25478.78.99.255254
10178.78.100.0/2478.78.100.1 to 78.78.100.25478.78.100.255254
10278.78.101.0/2478.78.101.1 to 78.78.101.25478.78.101.255254
10378.78.102.0/2478.78.102.1 to 78.78.102.25478.78.102.255254
10478.78.103.0/2478.78.103.1 to 78.78.103.25478.78.103.255254
10578.78.104.0/2478.78.104.1 to 78.78.104.25478.78.104.255254
10678.78.105.0/2478.78.105.1 to 78.78.105.25478.78.105.255254
10778.78.106.0/2478.78.106.1 to 78.78.106.25478.78.106.255254
10878.78.107.0/2478.78.107.1 to 78.78.107.25478.78.107.255254
10978.78.108.0/2478.78.108.1 to 78.78.108.25478.78.108.255254
11078.78.109.0/2478.78.109.1 to 78.78.109.25478.78.109.255254
11178.78.110.0/2478.78.110.1 to 78.78.110.25478.78.110.255254
11278.78.111.0/2478.78.111.1 to 78.78.111.25478.78.111.255254
11378.78.112.0/2478.78.112.1 to 78.78.112.25478.78.112.255254
11478.78.113.0/2478.78.113.1 to 78.78.113.25478.78.113.255254
11578.78.114.0/2478.78.114.1 to 78.78.114.25478.78.114.255254
11678.78.115.0/2478.78.115.1 to 78.78.115.25478.78.115.255254
11778.78.116.0/2478.78.116.1 to 78.78.116.25478.78.116.255254
11878.78.117.0/2478.78.117.1 to 78.78.117.25478.78.117.255254
11978.78.118.0/2478.78.118.1 to 78.78.118.25478.78.118.255254
12078.78.119.0/2478.78.119.1 to 78.78.119.25478.78.119.255254
12178.78.120.0/2478.78.120.1 to 78.78.120.25478.78.120.255254
12278.78.121.0/2478.78.121.1 to 78.78.121.25478.78.121.255254
12378.78.122.0/2478.78.122.1 to 78.78.122.25478.78.122.255254
12478.78.123.0/2478.78.123.1 to 78.78.123.25478.78.123.255254
12578.78.124.0/2478.78.124.1 to 78.78.124.25478.78.124.255254
12678.78.125.0/2478.78.125.1 to 78.78.125.25478.78.125.255254
12778.78.126.0/2478.78.126.1 to 78.78.126.25478.78.126.255254
12878.78.127.0/2478.78.127.1 to 78.78.127.25478.78.127.255254

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