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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.

Network35.80.0.0/14
Usable hosts262,142
Subnet mask255.252.0.0
Addresses262,144
Network address
35.80.0.0
Broadcast address
35.83.255.255
First usable
35.80.0.1
Last usable
35.83.255.254
Usable hosts
262,142 (262,144 less the network and broadcast addresses)
Subnet mask
255.252.0.0
Wildcard mask
0.3.255.255 (Cisco ACLs, OSPF)
Prefix length
/14
Type
Public public
Old class
A (default /8)
As numbers
Hex 23500000 · Integer 592445440 to 592707583
Reverse DNS zones
80.35.in-addr.arpa
81.35.in-addr.arpa
82.35.in-addr.arpa
83.35.in-addr.arpa
/14 is not on a 8-bit boundary, so it takes 4 /16 zones.
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address00100011.01010000.00000000.0000000035.80.0.0
Subnet mask11111111.11111100.00000000.00000000255.252.0.0
Network00100011.01010000.00000000.0000000035.80.0.0
Broadcast00100011.01010011.11111111.1111111135.83.255.255
Split into smaller subnets/21
/15 (2)/16 (4)/17 (8)/18 (16)/19 (32)/20 (64)/21 (128)/22 (256)/23 (512)/24 (1,024)/25 (2,048)/26 (4,096)

35.80.0.0/14 makes 128 subnets of /21.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
135.80.0.0/2135.80.0.1 to 35.80.7.25435.80.7.2552,046
235.80.8.0/2135.80.8.1 to 35.80.15.25435.80.15.2552,046
335.80.16.0/2135.80.16.1 to 35.80.23.25435.80.23.2552,046
435.80.24.0/2135.80.24.1 to 35.80.31.25435.80.31.2552,046
535.80.32.0/2135.80.32.1 to 35.80.39.25435.80.39.2552,046
635.80.40.0/2135.80.40.1 to 35.80.47.25435.80.47.2552,046
735.80.48.0/2135.80.48.1 to 35.80.55.25435.80.55.2552,046
835.80.56.0/2135.80.56.1 to 35.80.63.25435.80.63.2552,046
935.80.64.0/2135.80.64.1 to 35.80.71.25435.80.71.2552,046
1035.80.72.0/2135.80.72.1 to 35.80.79.25435.80.79.2552,046
1135.80.80.0/2135.80.80.1 to 35.80.87.25435.80.87.2552,046
1235.80.88.0/2135.80.88.1 to 35.80.95.25435.80.95.2552,046
1335.80.96.0/2135.80.96.1 to 35.80.103.25435.80.103.2552,046
1435.80.104.0/2135.80.104.1 to 35.80.111.25435.80.111.2552,046
1535.80.112.0/2135.80.112.1 to 35.80.119.25435.80.119.2552,046
1635.80.120.0/2135.80.120.1 to 35.80.127.25435.80.127.2552,046
1735.80.128.0/2135.80.128.1 to 35.80.135.25435.80.135.2552,046
1835.80.136.0/2135.80.136.1 to 35.80.143.25435.80.143.2552,046
1935.80.144.0/2135.80.144.1 to 35.80.151.25435.80.151.2552,046
2035.80.152.0/2135.80.152.1 to 35.80.159.25435.80.159.2552,046
2135.80.160.0/2135.80.160.1 to 35.80.167.25435.80.167.2552,046
2235.80.168.0/2135.80.168.1 to 35.80.175.25435.80.175.2552,046
2335.80.176.0/2135.80.176.1 to 35.80.183.25435.80.183.2552,046
2435.80.184.0/2135.80.184.1 to 35.80.191.25435.80.191.2552,046
2535.80.192.0/2135.80.192.1 to 35.80.199.25435.80.199.2552,046
2635.80.200.0/2135.80.200.1 to 35.80.207.25435.80.207.2552,046
2735.80.208.0/2135.80.208.1 to 35.80.215.25435.80.215.2552,046
2835.80.216.0/2135.80.216.1 to 35.80.223.25435.80.223.2552,046
2935.80.224.0/2135.80.224.1 to 35.80.231.25435.80.231.2552,046
3035.80.232.0/2135.80.232.1 to 35.80.239.25435.80.239.2552,046
3135.80.240.0/2135.80.240.1 to 35.80.247.25435.80.247.2552,046
3235.80.248.0/2135.80.248.1 to 35.80.255.25435.80.255.2552,046
3335.81.0.0/2135.81.0.1 to 35.81.7.25435.81.7.2552,046
3435.81.8.0/2135.81.8.1 to 35.81.15.25435.81.15.2552,046
3535.81.16.0/2135.81.16.1 to 35.81.23.25435.81.23.2552,046
3635.81.24.0/2135.81.24.1 to 35.81.31.25435.81.31.2552,046
3735.81.32.0/2135.81.32.1 to 35.81.39.25435.81.39.2552,046
3835.81.40.0/2135.81.40.1 to 35.81.47.25435.81.47.2552,046
3935.81.48.0/2135.81.48.1 to 35.81.55.25435.81.55.2552,046
4035.81.56.0/2135.81.56.1 to 35.81.63.25435.81.63.2552,046
4135.81.64.0/2135.81.64.1 to 35.81.71.25435.81.71.2552,046
4235.81.72.0/2135.81.72.1 to 35.81.79.25435.81.79.2552,046
4335.81.80.0/2135.81.80.1 to 35.81.87.25435.81.87.2552,046
4435.81.88.0/2135.81.88.1 to 35.81.95.25435.81.95.2552,046
4535.81.96.0/2135.81.96.1 to 35.81.103.25435.81.103.2552,046
4635.81.104.0/2135.81.104.1 to 35.81.111.25435.81.111.2552,046
4735.81.112.0/2135.81.112.1 to 35.81.119.25435.81.119.2552,046
4835.81.120.0/2135.81.120.1 to 35.81.127.25435.81.127.2552,046
4935.81.128.0/2135.81.128.1 to 35.81.135.25435.81.135.2552,046
5035.81.136.0/2135.81.136.1 to 35.81.143.25435.81.143.2552,046
5135.81.144.0/2135.81.144.1 to 35.81.151.25435.81.151.2552,046
5235.81.152.0/2135.81.152.1 to 35.81.159.25435.81.159.2552,046
5335.81.160.0/2135.81.160.1 to 35.81.167.25435.81.167.2552,046
5435.81.168.0/2135.81.168.1 to 35.81.175.25435.81.175.2552,046
5535.81.176.0/2135.81.176.1 to 35.81.183.25435.81.183.2552,046
5635.81.184.0/2135.81.184.1 to 35.81.191.25435.81.191.2552,046
5735.81.192.0/2135.81.192.1 to 35.81.199.25435.81.199.2552,046
5835.81.200.0/2135.81.200.1 to 35.81.207.25435.81.207.2552,046
5935.81.208.0/2135.81.208.1 to 35.81.215.25435.81.215.2552,046
6035.81.216.0/2135.81.216.1 to 35.81.223.25435.81.223.2552,046
6135.81.224.0/2135.81.224.1 to 35.81.231.25435.81.231.2552,046
6235.81.232.0/2135.81.232.1 to 35.81.239.25435.81.239.2552,046
6335.81.240.0/2135.81.240.1 to 35.81.247.25435.81.247.2552,046
6435.81.248.0/2135.81.248.1 to 35.81.255.25435.81.255.2552,046
6535.82.0.0/2135.82.0.1 to 35.82.7.25435.82.7.2552,046
6635.82.8.0/2135.82.8.1 to 35.82.15.25435.82.15.2552,046
6735.82.16.0/2135.82.16.1 to 35.82.23.25435.82.23.2552,046
6835.82.24.0/2135.82.24.1 to 35.82.31.25435.82.31.2552,046
6935.82.32.0/2135.82.32.1 to 35.82.39.25435.82.39.2552,046
7035.82.40.0/2135.82.40.1 to 35.82.47.25435.82.47.2552,046
7135.82.48.0/2135.82.48.1 to 35.82.55.25435.82.55.2552,046
7235.82.56.0/2135.82.56.1 to 35.82.63.25435.82.63.2552,046
7335.82.64.0/2135.82.64.1 to 35.82.71.25435.82.71.2552,046
7435.82.72.0/2135.82.72.1 to 35.82.79.25435.82.79.2552,046
7535.82.80.0/2135.82.80.1 to 35.82.87.25435.82.87.2552,046
7635.82.88.0/2135.82.88.1 to 35.82.95.25435.82.95.2552,046
7735.82.96.0/2135.82.96.1 to 35.82.103.25435.82.103.2552,046
7835.82.104.0/2135.82.104.1 to 35.82.111.25435.82.111.2552,046
7935.82.112.0/2135.82.112.1 to 35.82.119.25435.82.119.2552,046
8035.82.120.0/2135.82.120.1 to 35.82.127.25435.82.127.2552,046
8135.82.128.0/2135.82.128.1 to 35.82.135.25435.82.135.2552,046
8235.82.136.0/2135.82.136.1 to 35.82.143.25435.82.143.2552,046
8335.82.144.0/2135.82.144.1 to 35.82.151.25435.82.151.2552,046
8435.82.152.0/2135.82.152.1 to 35.82.159.25435.82.159.2552,046
8535.82.160.0/2135.82.160.1 to 35.82.167.25435.82.167.2552,046
8635.82.168.0/2135.82.168.1 to 35.82.175.25435.82.175.2552,046
8735.82.176.0/2135.82.176.1 to 35.82.183.25435.82.183.2552,046
8835.82.184.0/2135.82.184.1 to 35.82.191.25435.82.191.2552,046
8935.82.192.0/2135.82.192.1 to 35.82.199.25435.82.199.2552,046
9035.82.200.0/2135.82.200.1 to 35.82.207.25435.82.207.2552,046
9135.82.208.0/2135.82.208.1 to 35.82.215.25435.82.215.2552,046
9235.82.216.0/2135.82.216.1 to 35.82.223.25435.82.223.2552,046
9335.82.224.0/2135.82.224.1 to 35.82.231.25435.82.231.2552,046
9435.82.232.0/2135.82.232.1 to 35.82.239.25435.82.239.2552,046
9535.82.240.0/2135.82.240.1 to 35.82.247.25435.82.247.2552,046
9635.82.248.0/2135.82.248.1 to 35.82.255.25435.82.255.2552,046
9735.83.0.0/2135.83.0.1 to 35.83.7.25435.83.7.2552,046
9835.83.8.0/2135.83.8.1 to 35.83.15.25435.83.15.2552,046
9935.83.16.0/2135.83.16.1 to 35.83.23.25435.83.23.2552,046
10035.83.24.0/2135.83.24.1 to 35.83.31.25435.83.31.2552,046
10135.83.32.0/2135.83.32.1 to 35.83.39.25435.83.39.2552,046
10235.83.40.0/2135.83.40.1 to 35.83.47.25435.83.47.2552,046
10335.83.48.0/2135.83.48.1 to 35.83.55.25435.83.55.2552,046
10435.83.56.0/2135.83.56.1 to 35.83.63.25435.83.63.2552,046
10535.83.64.0/2135.83.64.1 to 35.83.71.25435.83.71.2552,046
10635.83.72.0/2135.83.72.1 to 35.83.79.25435.83.79.2552,046
10735.83.80.0/2135.83.80.1 to 35.83.87.25435.83.87.2552,046
10835.83.88.0/2135.83.88.1 to 35.83.95.25435.83.95.2552,046
10935.83.96.0/2135.83.96.1 to 35.83.103.25435.83.103.2552,046
11035.83.104.0/2135.83.104.1 to 35.83.111.25435.83.111.2552,046
11135.83.112.0/2135.83.112.1 to 35.83.119.25435.83.119.2552,046
11235.83.120.0/2135.83.120.1 to 35.83.127.25435.83.127.2552,046
11335.83.128.0/2135.83.128.1 to 35.83.135.25435.83.135.2552,046
11435.83.136.0/2135.83.136.1 to 35.83.143.25435.83.143.2552,046
11535.83.144.0/2135.83.144.1 to 35.83.151.25435.83.151.2552,046
11635.83.152.0/2135.83.152.1 to 35.83.159.25435.83.159.2552,046
11735.83.160.0/2135.83.160.1 to 35.83.167.25435.83.167.2552,046
11835.83.168.0/2135.83.168.1 to 35.83.175.25435.83.175.2552,046
11935.83.176.0/2135.83.176.1 to 35.83.183.25435.83.183.2552,046
12035.83.184.0/2135.83.184.1 to 35.83.191.25435.83.191.2552,046
12135.83.192.0/2135.83.192.1 to 35.83.199.25435.83.199.2552,046
12235.83.200.0/2135.83.200.1 to 35.83.207.25435.83.207.2552,046
12335.83.208.0/2135.83.208.1 to 35.83.215.25435.83.215.2552,046
12435.83.216.0/2135.83.216.1 to 35.83.223.25435.83.223.2552,046
12535.83.224.0/2135.83.224.1 to 35.83.231.25435.83.231.2552,046
12635.83.232.0/2135.83.232.1 to 35.83.239.25435.83.239.2552,046
12735.83.240.0/2135.83.240.1 to 35.83.247.25435.83.247.2552,046
12835.83.248.0/2135.83.248.1 to 35.83.255.25435.83.255.2552,046

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.