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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.

Network59.64.0.0/13
Usable hosts524,286
Subnet mask255.248.0.0
Addresses524,288
Network address
59.64.0.0
Broadcast address
59.71.255.255
First usable
59.64.0.1
Last usable
59.71.255.254
Usable hosts
524,286 (524,288 less the network and broadcast addresses)
Subnet mask
255.248.0.0
Wildcard mask
0.7.255.255 (Cisco ACLs, OSPF)
Prefix length
/13
Type
Public public
Old class
A (default /8)
As numbers
Hex 3B400000 · Integer 994050048 to 994574335
Reverse DNS zones
64.59.in-addr.arpa
65.59.in-addr.arpa
66.59.in-addr.arpa
67.59.in-addr.arpa
68.59.in-addr.arpa
69.59.in-addr.arpa
70.59.in-addr.arpa
71.59.in-addr.arpa
/13 is not on a 8-bit boundary, so it takes 8 /16 zones.
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address00111011.01000000.00000000.0000000059.64.0.0
Subnet mask11111111.11111000.00000000.00000000255.248.0.0
Network00111011.01000000.00000000.0000000059.64.0.0
Broadcast00111011.01000111.11111111.1111111159.71.255.255
Split into smaller subnets/20

59.64.0.0/13 makes 128 subnets of /20.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
159.64.0.0/2059.64.0.1 to 59.64.15.25459.64.15.2554,094
259.64.16.0/2059.64.16.1 to 59.64.31.25459.64.31.2554,094
359.64.32.0/2059.64.32.1 to 59.64.47.25459.64.47.2554,094
459.64.48.0/2059.64.48.1 to 59.64.63.25459.64.63.2554,094
559.64.64.0/2059.64.64.1 to 59.64.79.25459.64.79.2554,094
659.64.80.0/2059.64.80.1 to 59.64.95.25459.64.95.2554,094
759.64.96.0/2059.64.96.1 to 59.64.111.25459.64.111.2554,094
859.64.112.0/2059.64.112.1 to 59.64.127.25459.64.127.2554,094
959.64.128.0/2059.64.128.1 to 59.64.143.25459.64.143.2554,094
1059.64.144.0/2059.64.144.1 to 59.64.159.25459.64.159.2554,094
1159.64.160.0/2059.64.160.1 to 59.64.175.25459.64.175.2554,094
1259.64.176.0/2059.64.176.1 to 59.64.191.25459.64.191.2554,094
1359.64.192.0/2059.64.192.1 to 59.64.207.25459.64.207.2554,094
1459.64.208.0/2059.64.208.1 to 59.64.223.25459.64.223.2554,094
1559.64.224.0/2059.64.224.1 to 59.64.239.25459.64.239.2554,094
1659.64.240.0/2059.64.240.1 to 59.64.255.25459.64.255.2554,094
1759.65.0.0/2059.65.0.1 to 59.65.15.25459.65.15.2554,094
1859.65.16.0/2059.65.16.1 to 59.65.31.25459.65.31.2554,094
1959.65.32.0/2059.65.32.1 to 59.65.47.25459.65.47.2554,094
2059.65.48.0/2059.65.48.1 to 59.65.63.25459.65.63.2554,094
2159.65.64.0/2059.65.64.1 to 59.65.79.25459.65.79.2554,094
2259.65.80.0/2059.65.80.1 to 59.65.95.25459.65.95.2554,094
2359.65.96.0/2059.65.96.1 to 59.65.111.25459.65.111.2554,094
2459.65.112.0/2059.65.112.1 to 59.65.127.25459.65.127.2554,094
2559.65.128.0/2059.65.128.1 to 59.65.143.25459.65.143.2554,094
2659.65.144.0/2059.65.144.1 to 59.65.159.25459.65.159.2554,094
2759.65.160.0/2059.65.160.1 to 59.65.175.25459.65.175.2554,094
2859.65.176.0/2059.65.176.1 to 59.65.191.25459.65.191.2554,094
2959.65.192.0/2059.65.192.1 to 59.65.207.25459.65.207.2554,094
3059.65.208.0/2059.65.208.1 to 59.65.223.25459.65.223.2554,094
3159.65.224.0/2059.65.224.1 to 59.65.239.25459.65.239.2554,094
3259.65.240.0/2059.65.240.1 to 59.65.255.25459.65.255.2554,094
3359.66.0.0/2059.66.0.1 to 59.66.15.25459.66.15.2554,094
3459.66.16.0/2059.66.16.1 to 59.66.31.25459.66.31.2554,094
3559.66.32.0/2059.66.32.1 to 59.66.47.25459.66.47.2554,094
3659.66.48.0/2059.66.48.1 to 59.66.63.25459.66.63.2554,094
3759.66.64.0/2059.66.64.1 to 59.66.79.25459.66.79.2554,094
3859.66.80.0/2059.66.80.1 to 59.66.95.25459.66.95.2554,094
3959.66.96.0/2059.66.96.1 to 59.66.111.25459.66.111.2554,094
4059.66.112.0/2059.66.112.1 to 59.66.127.25459.66.127.2554,094
4159.66.128.0/2059.66.128.1 to 59.66.143.25459.66.143.2554,094
4259.66.144.0/2059.66.144.1 to 59.66.159.25459.66.159.2554,094
4359.66.160.0/2059.66.160.1 to 59.66.175.25459.66.175.2554,094
4459.66.176.0/2059.66.176.1 to 59.66.191.25459.66.191.2554,094
4559.66.192.0/2059.66.192.1 to 59.66.207.25459.66.207.2554,094
4659.66.208.0/2059.66.208.1 to 59.66.223.25459.66.223.2554,094
4759.66.224.0/2059.66.224.1 to 59.66.239.25459.66.239.2554,094
4859.66.240.0/2059.66.240.1 to 59.66.255.25459.66.255.2554,094
4959.67.0.0/2059.67.0.1 to 59.67.15.25459.67.15.2554,094
5059.67.16.0/2059.67.16.1 to 59.67.31.25459.67.31.2554,094
5159.67.32.0/2059.67.32.1 to 59.67.47.25459.67.47.2554,094
5259.67.48.0/2059.67.48.1 to 59.67.63.25459.67.63.2554,094
5359.67.64.0/2059.67.64.1 to 59.67.79.25459.67.79.2554,094
5459.67.80.0/2059.67.80.1 to 59.67.95.25459.67.95.2554,094
5559.67.96.0/2059.67.96.1 to 59.67.111.25459.67.111.2554,094
5659.67.112.0/2059.67.112.1 to 59.67.127.25459.67.127.2554,094
5759.67.128.0/2059.67.128.1 to 59.67.143.25459.67.143.2554,094
5859.67.144.0/2059.67.144.1 to 59.67.159.25459.67.159.2554,094
5959.67.160.0/2059.67.160.1 to 59.67.175.25459.67.175.2554,094
6059.67.176.0/2059.67.176.1 to 59.67.191.25459.67.191.2554,094
6159.67.192.0/2059.67.192.1 to 59.67.207.25459.67.207.2554,094
6259.67.208.0/2059.67.208.1 to 59.67.223.25459.67.223.2554,094
6359.67.224.0/2059.67.224.1 to 59.67.239.25459.67.239.2554,094
6459.67.240.0/2059.67.240.1 to 59.67.255.25459.67.255.2554,094
6559.68.0.0/2059.68.0.1 to 59.68.15.25459.68.15.2554,094
6659.68.16.0/2059.68.16.1 to 59.68.31.25459.68.31.2554,094
6759.68.32.0/2059.68.32.1 to 59.68.47.25459.68.47.2554,094
6859.68.48.0/2059.68.48.1 to 59.68.63.25459.68.63.2554,094
6959.68.64.0/2059.68.64.1 to 59.68.79.25459.68.79.2554,094
7059.68.80.0/2059.68.80.1 to 59.68.95.25459.68.95.2554,094
7159.68.96.0/2059.68.96.1 to 59.68.111.25459.68.111.2554,094
7259.68.112.0/2059.68.112.1 to 59.68.127.25459.68.127.2554,094
7359.68.128.0/2059.68.128.1 to 59.68.143.25459.68.143.2554,094
7459.68.144.0/2059.68.144.1 to 59.68.159.25459.68.159.2554,094
7559.68.160.0/2059.68.160.1 to 59.68.175.25459.68.175.2554,094
7659.68.176.0/2059.68.176.1 to 59.68.191.25459.68.191.2554,094
7759.68.192.0/2059.68.192.1 to 59.68.207.25459.68.207.2554,094
7859.68.208.0/2059.68.208.1 to 59.68.223.25459.68.223.2554,094
7959.68.224.0/2059.68.224.1 to 59.68.239.25459.68.239.2554,094
8059.68.240.0/2059.68.240.1 to 59.68.255.25459.68.255.2554,094
8159.69.0.0/2059.69.0.1 to 59.69.15.25459.69.15.2554,094
8259.69.16.0/2059.69.16.1 to 59.69.31.25459.69.31.2554,094
8359.69.32.0/2059.69.32.1 to 59.69.47.25459.69.47.2554,094
8459.69.48.0/2059.69.48.1 to 59.69.63.25459.69.63.2554,094
8559.69.64.0/2059.69.64.1 to 59.69.79.25459.69.79.2554,094
8659.69.80.0/2059.69.80.1 to 59.69.95.25459.69.95.2554,094
8759.69.96.0/2059.69.96.1 to 59.69.111.25459.69.111.2554,094
8859.69.112.0/2059.69.112.1 to 59.69.127.25459.69.127.2554,094
8959.69.128.0/2059.69.128.1 to 59.69.143.25459.69.143.2554,094
9059.69.144.0/2059.69.144.1 to 59.69.159.25459.69.159.2554,094
9159.69.160.0/2059.69.160.1 to 59.69.175.25459.69.175.2554,094
9259.69.176.0/2059.69.176.1 to 59.69.191.25459.69.191.2554,094
9359.69.192.0/2059.69.192.1 to 59.69.207.25459.69.207.2554,094
9459.69.208.0/2059.69.208.1 to 59.69.223.25459.69.223.2554,094
9559.69.224.0/2059.69.224.1 to 59.69.239.25459.69.239.2554,094
9659.69.240.0/2059.69.240.1 to 59.69.255.25459.69.255.2554,094
9759.70.0.0/2059.70.0.1 to 59.70.15.25459.70.15.2554,094
9859.70.16.0/2059.70.16.1 to 59.70.31.25459.70.31.2554,094
9959.70.32.0/2059.70.32.1 to 59.70.47.25459.70.47.2554,094
10059.70.48.0/2059.70.48.1 to 59.70.63.25459.70.63.2554,094
10159.70.64.0/2059.70.64.1 to 59.70.79.25459.70.79.2554,094
10259.70.80.0/2059.70.80.1 to 59.70.95.25459.70.95.2554,094
10359.70.96.0/2059.70.96.1 to 59.70.111.25459.70.111.2554,094
10459.70.112.0/2059.70.112.1 to 59.70.127.25459.70.127.2554,094
10559.70.128.0/2059.70.128.1 to 59.70.143.25459.70.143.2554,094
10659.70.144.0/2059.70.144.1 to 59.70.159.25459.70.159.2554,094
10759.70.160.0/2059.70.160.1 to 59.70.175.25459.70.175.2554,094
10859.70.176.0/2059.70.176.1 to 59.70.191.25459.70.191.2554,094
10959.70.192.0/2059.70.192.1 to 59.70.207.25459.70.207.2554,094
11059.70.208.0/2059.70.208.1 to 59.70.223.25459.70.223.2554,094
11159.70.224.0/2059.70.224.1 to 59.70.239.25459.70.239.2554,094
11259.70.240.0/2059.70.240.1 to 59.70.255.25459.70.255.2554,094
11359.71.0.0/2059.71.0.1 to 59.71.15.25459.71.15.2554,094
11459.71.16.0/2059.71.16.1 to 59.71.31.25459.71.31.2554,094
11559.71.32.0/2059.71.32.1 to 59.71.47.25459.71.47.2554,094
11659.71.48.0/2059.71.48.1 to 59.71.63.25459.71.63.2554,094
11759.71.64.0/2059.71.64.1 to 59.71.79.25459.71.79.2554,094
11859.71.80.0/2059.71.80.1 to 59.71.95.25459.71.95.2554,094
11959.71.96.0/2059.71.96.1 to 59.71.111.25459.71.111.2554,094
12059.71.112.0/2059.71.112.1 to 59.71.127.25459.71.127.2554,094
12159.71.128.0/2059.71.128.1 to 59.71.143.25459.71.143.2554,094
12259.71.144.0/2059.71.144.1 to 59.71.159.25459.71.159.2554,094
12359.71.160.0/2059.71.160.1 to 59.71.175.25459.71.175.2554,094
12459.71.176.0/2059.71.176.1 to 59.71.191.25459.71.191.2554,094
12559.71.192.0/2059.71.192.1 to 59.71.207.25459.71.207.2554,094
12659.71.208.0/2059.71.208.1 to 59.71.223.25459.71.223.2554,094
12759.71.224.0/2059.71.224.1 to 59.71.239.25459.71.239.2554,094
12859.71.240.0/2059.71.240.1 to 59.71.255.25459.71.255.2554,094

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