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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.

Network82.192.0.0/10
Usable hosts4,194,302
Subnet mask255.192.0.0
Addresses4,194,304
Network address
82.192.0.0
Broadcast address
82.255.255.255
First usable
82.192.0.1
Last usable
82.255.255.254
Usable hosts
4,194,302 (4,194,304 less the network and broadcast addresses)
Subnet mask
255.192.0.0
Wildcard mask
0.63.255.255 (Cisco ACLs, OSPF)
Prefix length
/10
Type
Public public
Old class
A (default /8)
As numbers
Hex 52C00000 · Integer 1388314624 to 1392508927
Reverse DNS zones
192.82.in-addr.arpa
193.82.in-addr.arpa
194.82.in-addr.arpa
195.82.in-addr.arpa
196.82.in-addr.arpa
197.82.in-addr.arpa
198.82.in-addr.arpa
199.82.in-addr.arpa
200.82.in-addr.arpa
201.82.in-addr.arpa
202.82.in-addr.arpa
203.82.in-addr.arpa
204.82.in-addr.arpa
205.82.in-addr.arpa
206.82.in-addr.arpa
207.82.in-addr.arpa
and 48 more
/10 is not on a 8-bit boundary, so it takes 64 /16 zones.
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address01010010.11000000.00000000.0000000082.192.0.0
Subnet mask11111111.11000000.00000000.00000000255.192.0.0
Network01010010.11000000.00000000.0000000082.192.0.0
Broadcast01010010.11111111.11111111.1111111182.255.255.255
Split into smaller subnets/17

82.192.0.0/10 makes 128 subnets of /17.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
182.192.0.0/1782.192.0.1 to 82.192.127.25482.192.127.25532,766
282.192.128.0/1782.192.128.1 to 82.192.255.25482.192.255.25532,766
382.193.0.0/1782.193.0.1 to 82.193.127.25482.193.127.25532,766
482.193.128.0/1782.193.128.1 to 82.193.255.25482.193.255.25532,766
582.194.0.0/1782.194.0.1 to 82.194.127.25482.194.127.25532,766
682.194.128.0/1782.194.128.1 to 82.194.255.25482.194.255.25532,766
782.195.0.0/1782.195.0.1 to 82.195.127.25482.195.127.25532,766
882.195.128.0/1782.195.128.1 to 82.195.255.25482.195.255.25532,766
982.196.0.0/1782.196.0.1 to 82.196.127.25482.196.127.25532,766
1082.196.128.0/1782.196.128.1 to 82.196.255.25482.196.255.25532,766
1182.197.0.0/1782.197.0.1 to 82.197.127.25482.197.127.25532,766
1282.197.128.0/1782.197.128.1 to 82.197.255.25482.197.255.25532,766
1382.198.0.0/1782.198.0.1 to 82.198.127.25482.198.127.25532,766
1482.198.128.0/1782.198.128.1 to 82.198.255.25482.198.255.25532,766
1582.199.0.0/1782.199.0.1 to 82.199.127.25482.199.127.25532,766
1682.199.128.0/1782.199.128.1 to 82.199.255.25482.199.255.25532,766
1782.200.0.0/1782.200.0.1 to 82.200.127.25482.200.127.25532,766
1882.200.128.0/1782.200.128.1 to 82.200.255.25482.200.255.25532,766
1982.201.0.0/1782.201.0.1 to 82.201.127.25482.201.127.25532,766
2082.201.128.0/1782.201.128.1 to 82.201.255.25482.201.255.25532,766
2182.202.0.0/1782.202.0.1 to 82.202.127.25482.202.127.25532,766
2282.202.128.0/1782.202.128.1 to 82.202.255.25482.202.255.25532,766
2382.203.0.0/1782.203.0.1 to 82.203.127.25482.203.127.25532,766
2482.203.128.0/1782.203.128.1 to 82.203.255.25482.203.255.25532,766
2582.204.0.0/1782.204.0.1 to 82.204.127.25482.204.127.25532,766
2682.204.128.0/1782.204.128.1 to 82.204.255.25482.204.255.25532,766
2782.205.0.0/1782.205.0.1 to 82.205.127.25482.205.127.25532,766
2882.205.128.0/1782.205.128.1 to 82.205.255.25482.205.255.25532,766
2982.206.0.0/1782.206.0.1 to 82.206.127.25482.206.127.25532,766
3082.206.128.0/1782.206.128.1 to 82.206.255.25482.206.255.25532,766
3182.207.0.0/1782.207.0.1 to 82.207.127.25482.207.127.25532,766
3282.207.128.0/1782.207.128.1 to 82.207.255.25482.207.255.25532,766
3382.208.0.0/1782.208.0.1 to 82.208.127.25482.208.127.25532,766
3482.208.128.0/1782.208.128.1 to 82.208.255.25482.208.255.25532,766
3582.209.0.0/1782.209.0.1 to 82.209.127.25482.209.127.25532,766
3682.209.128.0/1782.209.128.1 to 82.209.255.25482.209.255.25532,766
3782.210.0.0/1782.210.0.1 to 82.210.127.25482.210.127.25532,766
3882.210.128.0/1782.210.128.1 to 82.210.255.25482.210.255.25532,766
3982.211.0.0/1782.211.0.1 to 82.211.127.25482.211.127.25532,766
4082.211.128.0/1782.211.128.1 to 82.211.255.25482.211.255.25532,766
4182.212.0.0/1782.212.0.1 to 82.212.127.25482.212.127.25532,766
4282.212.128.0/1782.212.128.1 to 82.212.255.25482.212.255.25532,766
4382.213.0.0/1782.213.0.1 to 82.213.127.25482.213.127.25532,766
4482.213.128.0/1782.213.128.1 to 82.213.255.25482.213.255.25532,766
4582.214.0.0/1782.214.0.1 to 82.214.127.25482.214.127.25532,766
4682.214.128.0/1782.214.128.1 to 82.214.255.25482.214.255.25532,766
4782.215.0.0/1782.215.0.1 to 82.215.127.25482.215.127.25532,766
4882.215.128.0/1782.215.128.1 to 82.215.255.25482.215.255.25532,766
4982.216.0.0/1782.216.0.1 to 82.216.127.25482.216.127.25532,766
5082.216.128.0/1782.216.128.1 to 82.216.255.25482.216.255.25532,766
5182.217.0.0/1782.217.0.1 to 82.217.127.25482.217.127.25532,766
5282.217.128.0/1782.217.128.1 to 82.217.255.25482.217.255.25532,766
5382.218.0.0/1782.218.0.1 to 82.218.127.25482.218.127.25532,766
5482.218.128.0/1782.218.128.1 to 82.218.255.25482.218.255.25532,766
5582.219.0.0/1782.219.0.1 to 82.219.127.25482.219.127.25532,766
5682.219.128.0/1782.219.128.1 to 82.219.255.25482.219.255.25532,766
5782.220.0.0/1782.220.0.1 to 82.220.127.25482.220.127.25532,766
5882.220.128.0/1782.220.128.1 to 82.220.255.25482.220.255.25532,766
5982.221.0.0/1782.221.0.1 to 82.221.127.25482.221.127.25532,766
6082.221.128.0/1782.221.128.1 to 82.221.255.25482.221.255.25532,766
6182.222.0.0/1782.222.0.1 to 82.222.127.25482.222.127.25532,766
6282.222.128.0/1782.222.128.1 to 82.222.255.25482.222.255.25532,766
6382.223.0.0/1782.223.0.1 to 82.223.127.25482.223.127.25532,766
6482.223.128.0/1782.223.128.1 to 82.223.255.25482.223.255.25532,766
6582.224.0.0/1782.224.0.1 to 82.224.127.25482.224.127.25532,766
6682.224.128.0/1782.224.128.1 to 82.224.255.25482.224.255.25532,766
6782.225.0.0/1782.225.0.1 to 82.225.127.25482.225.127.25532,766
6882.225.128.0/1782.225.128.1 to 82.225.255.25482.225.255.25532,766
6982.226.0.0/1782.226.0.1 to 82.226.127.25482.226.127.25532,766
7082.226.128.0/1782.226.128.1 to 82.226.255.25482.226.255.25532,766
7182.227.0.0/1782.227.0.1 to 82.227.127.25482.227.127.25532,766
7282.227.128.0/1782.227.128.1 to 82.227.255.25482.227.255.25532,766
7382.228.0.0/1782.228.0.1 to 82.228.127.25482.228.127.25532,766
7482.228.128.0/1782.228.128.1 to 82.228.255.25482.228.255.25532,766
7582.229.0.0/1782.229.0.1 to 82.229.127.25482.229.127.25532,766
7682.229.128.0/1782.229.128.1 to 82.229.255.25482.229.255.25532,766
7782.230.0.0/1782.230.0.1 to 82.230.127.25482.230.127.25532,766
7882.230.128.0/1782.230.128.1 to 82.230.255.25482.230.255.25532,766
7982.231.0.0/1782.231.0.1 to 82.231.127.25482.231.127.25532,766
8082.231.128.0/1782.231.128.1 to 82.231.255.25482.231.255.25532,766
8182.232.0.0/1782.232.0.1 to 82.232.127.25482.232.127.25532,766
8282.232.128.0/1782.232.128.1 to 82.232.255.25482.232.255.25532,766
8382.233.0.0/1782.233.0.1 to 82.233.127.25482.233.127.25532,766
8482.233.128.0/1782.233.128.1 to 82.233.255.25482.233.255.25532,766
8582.234.0.0/1782.234.0.1 to 82.234.127.25482.234.127.25532,766
8682.234.128.0/1782.234.128.1 to 82.234.255.25482.234.255.25532,766
8782.235.0.0/1782.235.0.1 to 82.235.127.25482.235.127.25532,766
8882.235.128.0/1782.235.128.1 to 82.235.255.25482.235.255.25532,766
8982.236.0.0/1782.236.0.1 to 82.236.127.25482.236.127.25532,766
9082.236.128.0/1782.236.128.1 to 82.236.255.25482.236.255.25532,766
9182.237.0.0/1782.237.0.1 to 82.237.127.25482.237.127.25532,766
9282.237.128.0/1782.237.128.1 to 82.237.255.25482.237.255.25532,766
9382.238.0.0/1782.238.0.1 to 82.238.127.25482.238.127.25532,766
9482.238.128.0/1782.238.128.1 to 82.238.255.25482.238.255.25532,766
9582.239.0.0/1782.239.0.1 to 82.239.127.25482.239.127.25532,766
9682.239.128.0/1782.239.128.1 to 82.239.255.25482.239.255.25532,766
9782.240.0.0/1782.240.0.1 to 82.240.127.25482.240.127.25532,766
9882.240.128.0/1782.240.128.1 to 82.240.255.25482.240.255.25532,766
9982.241.0.0/1782.241.0.1 to 82.241.127.25482.241.127.25532,766
10082.241.128.0/1782.241.128.1 to 82.241.255.25482.241.255.25532,766
10182.242.0.0/1782.242.0.1 to 82.242.127.25482.242.127.25532,766
10282.242.128.0/1782.242.128.1 to 82.242.255.25482.242.255.25532,766
10382.243.0.0/1782.243.0.1 to 82.243.127.25482.243.127.25532,766
10482.243.128.0/1782.243.128.1 to 82.243.255.25482.243.255.25532,766
10582.244.0.0/1782.244.0.1 to 82.244.127.25482.244.127.25532,766
10682.244.128.0/1782.244.128.1 to 82.244.255.25482.244.255.25532,766
10782.245.0.0/1782.245.0.1 to 82.245.127.25482.245.127.25532,766
10882.245.128.0/1782.245.128.1 to 82.245.255.25482.245.255.25532,766
10982.246.0.0/1782.246.0.1 to 82.246.127.25482.246.127.25532,766
11082.246.128.0/1782.246.128.1 to 82.246.255.25482.246.255.25532,766
11182.247.0.0/1782.247.0.1 to 82.247.127.25482.247.127.25532,766
11282.247.128.0/1782.247.128.1 to 82.247.255.25482.247.255.25532,766
11382.248.0.0/1782.248.0.1 to 82.248.127.25482.248.127.25532,766
11482.248.128.0/1782.248.128.1 to 82.248.255.25482.248.255.25532,766
11582.249.0.0/1782.249.0.1 to 82.249.127.25482.249.127.25532,766
11682.249.128.0/1782.249.128.1 to 82.249.255.25482.249.255.25532,766
11782.250.0.0/1782.250.0.1 to 82.250.127.25482.250.127.25532,766
11882.250.128.0/1782.250.128.1 to 82.250.255.25482.250.255.25532,766
11982.251.0.0/1782.251.0.1 to 82.251.127.25482.251.127.25532,766
12082.251.128.0/1782.251.128.1 to 82.251.255.25482.251.255.25532,766
12182.252.0.0/1782.252.0.1 to 82.252.127.25482.252.127.25532,766
12282.252.128.0/1782.252.128.1 to 82.252.255.25482.252.255.25532,766
12382.253.0.0/1782.253.0.1 to 82.253.127.25482.253.127.25532,766
12482.253.128.0/1782.253.128.1 to 82.253.255.25482.253.255.25532,766
12582.254.0.0/1782.254.0.1 to 82.254.127.25482.254.127.25532,766
12682.254.128.0/1782.254.128.1 to 82.254.255.25482.254.255.25532,766
12782.255.0.0/1782.255.0.1 to 82.255.127.25482.255.127.25532,766
12882.255.128.0/1782.255.128.1 to 82.255.255.25482.255.255.25532,766

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