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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.

Network59.0.0.0/9
Usable hosts8,388,606
Subnet mask255.128.0.0
Addresses8,388,608
Network address
59.0.0.0
Broadcast address
59.127.255.255
First usable
59.0.0.1
Last usable
59.127.255.254
Usable hosts
8,388,606 (8,388,608 less the network and broadcast addresses)
Subnet mask
255.128.0.0
Wildcard mask
0.127.255.255 (Cisco ACLs, OSPF)
Prefix length
/9
Type
Public public
Old class
A (default /8)
As numbers
Hex 3B000000 · Integer 989855744 to 998244351
Reverse DNS zones
0.59.in-addr.arpa
1.59.in-addr.arpa
2.59.in-addr.arpa
3.59.in-addr.arpa
4.59.in-addr.arpa
5.59.in-addr.arpa
6.59.in-addr.arpa
7.59.in-addr.arpa
8.59.in-addr.arpa
9.59.in-addr.arpa
10.59.in-addr.arpa
11.59.in-addr.arpa
12.59.in-addr.arpa
13.59.in-addr.arpa
14.59.in-addr.arpa
15.59.in-addr.arpa
and 112 more
/9 is not on a 8-bit boundary, so it takes 128 /16 zones.
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address00111011.00000000.00000000.0000000059.0.0.0
Subnet mask11111111.10000000.00000000.00000000255.128.0.0
Network00111011.00000000.00000000.0000000059.0.0.0
Broadcast00111011.01111111.11111111.1111111159.127.255.255
Split into smaller subnets/16

59.0.0.0/9 makes 128 subnets of /16.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
159.0.0.0/1659.0.0.1 to 59.0.255.25459.0.255.25565,534
259.1.0.0/1659.1.0.1 to 59.1.255.25459.1.255.25565,534
359.2.0.0/1659.2.0.1 to 59.2.255.25459.2.255.25565,534
459.3.0.0/1659.3.0.1 to 59.3.255.25459.3.255.25565,534
559.4.0.0/1659.4.0.1 to 59.4.255.25459.4.255.25565,534
659.5.0.0/1659.5.0.1 to 59.5.255.25459.5.255.25565,534
759.6.0.0/1659.6.0.1 to 59.6.255.25459.6.255.25565,534
859.7.0.0/1659.7.0.1 to 59.7.255.25459.7.255.25565,534
959.8.0.0/1659.8.0.1 to 59.8.255.25459.8.255.25565,534
1059.9.0.0/1659.9.0.1 to 59.9.255.25459.9.255.25565,534
1159.10.0.0/1659.10.0.1 to 59.10.255.25459.10.255.25565,534
1259.11.0.0/1659.11.0.1 to 59.11.255.25459.11.255.25565,534
1359.12.0.0/1659.12.0.1 to 59.12.255.25459.12.255.25565,534
1459.13.0.0/1659.13.0.1 to 59.13.255.25459.13.255.25565,534
1559.14.0.0/1659.14.0.1 to 59.14.255.25459.14.255.25565,534
1659.15.0.0/1659.15.0.1 to 59.15.255.25459.15.255.25565,534
1759.16.0.0/1659.16.0.1 to 59.16.255.25459.16.255.25565,534
1859.17.0.0/1659.17.0.1 to 59.17.255.25459.17.255.25565,534
1959.18.0.0/1659.18.0.1 to 59.18.255.25459.18.255.25565,534
2059.19.0.0/1659.19.0.1 to 59.19.255.25459.19.255.25565,534
2159.20.0.0/1659.20.0.1 to 59.20.255.25459.20.255.25565,534
2259.21.0.0/1659.21.0.1 to 59.21.255.25459.21.255.25565,534
2359.22.0.0/1659.22.0.1 to 59.22.255.25459.22.255.25565,534
2459.23.0.0/1659.23.0.1 to 59.23.255.25459.23.255.25565,534
2559.24.0.0/1659.24.0.1 to 59.24.255.25459.24.255.25565,534
2659.25.0.0/1659.25.0.1 to 59.25.255.25459.25.255.25565,534
2759.26.0.0/1659.26.0.1 to 59.26.255.25459.26.255.25565,534
2859.27.0.0/1659.27.0.1 to 59.27.255.25459.27.255.25565,534
2959.28.0.0/1659.28.0.1 to 59.28.255.25459.28.255.25565,534
3059.29.0.0/1659.29.0.1 to 59.29.255.25459.29.255.25565,534
3159.30.0.0/1659.30.0.1 to 59.30.255.25459.30.255.25565,534
3259.31.0.0/1659.31.0.1 to 59.31.255.25459.31.255.25565,534
3359.32.0.0/1659.32.0.1 to 59.32.255.25459.32.255.25565,534
3459.33.0.0/1659.33.0.1 to 59.33.255.25459.33.255.25565,534
3559.34.0.0/1659.34.0.1 to 59.34.255.25459.34.255.25565,534
3659.35.0.0/1659.35.0.1 to 59.35.255.25459.35.255.25565,534
3759.36.0.0/1659.36.0.1 to 59.36.255.25459.36.255.25565,534
3859.37.0.0/1659.37.0.1 to 59.37.255.25459.37.255.25565,534
3959.38.0.0/1659.38.0.1 to 59.38.255.25459.38.255.25565,534
4059.39.0.0/1659.39.0.1 to 59.39.255.25459.39.255.25565,534
4159.40.0.0/1659.40.0.1 to 59.40.255.25459.40.255.25565,534
4259.41.0.0/1659.41.0.1 to 59.41.255.25459.41.255.25565,534
4359.42.0.0/1659.42.0.1 to 59.42.255.25459.42.255.25565,534
4459.43.0.0/1659.43.0.1 to 59.43.255.25459.43.255.25565,534
4559.44.0.0/1659.44.0.1 to 59.44.255.25459.44.255.25565,534
4659.45.0.0/1659.45.0.1 to 59.45.255.25459.45.255.25565,534
4759.46.0.0/1659.46.0.1 to 59.46.255.25459.46.255.25565,534
4859.47.0.0/1659.47.0.1 to 59.47.255.25459.47.255.25565,534
4959.48.0.0/1659.48.0.1 to 59.48.255.25459.48.255.25565,534
5059.49.0.0/1659.49.0.1 to 59.49.255.25459.49.255.25565,534
5159.50.0.0/1659.50.0.1 to 59.50.255.25459.50.255.25565,534
5259.51.0.0/1659.51.0.1 to 59.51.255.25459.51.255.25565,534
5359.52.0.0/1659.52.0.1 to 59.52.255.25459.52.255.25565,534
5459.53.0.0/1659.53.0.1 to 59.53.255.25459.53.255.25565,534
5559.54.0.0/1659.54.0.1 to 59.54.255.25459.54.255.25565,534
5659.55.0.0/1659.55.0.1 to 59.55.255.25459.55.255.25565,534
5759.56.0.0/1659.56.0.1 to 59.56.255.25459.56.255.25565,534
5859.57.0.0/1659.57.0.1 to 59.57.255.25459.57.255.25565,534
5959.58.0.0/1659.58.0.1 to 59.58.255.25459.58.255.25565,534
6059.59.0.0/1659.59.0.1 to 59.59.255.25459.59.255.25565,534
6159.60.0.0/1659.60.0.1 to 59.60.255.25459.60.255.25565,534
6259.61.0.0/1659.61.0.1 to 59.61.255.25459.61.255.25565,534
6359.62.0.0/1659.62.0.1 to 59.62.255.25459.62.255.25565,534
6459.63.0.0/1659.63.0.1 to 59.63.255.25459.63.255.25565,534
6559.64.0.0/1659.64.0.1 to 59.64.255.25459.64.255.25565,534
6659.65.0.0/1659.65.0.1 to 59.65.255.25459.65.255.25565,534
6759.66.0.0/1659.66.0.1 to 59.66.255.25459.66.255.25565,534
6859.67.0.0/1659.67.0.1 to 59.67.255.25459.67.255.25565,534
6959.68.0.0/1659.68.0.1 to 59.68.255.25459.68.255.25565,534
7059.69.0.0/1659.69.0.1 to 59.69.255.25459.69.255.25565,534
7159.70.0.0/1659.70.0.1 to 59.70.255.25459.70.255.25565,534
7259.71.0.0/1659.71.0.1 to 59.71.255.25459.71.255.25565,534
7359.72.0.0/1659.72.0.1 to 59.72.255.25459.72.255.25565,534
7459.73.0.0/1659.73.0.1 to 59.73.255.25459.73.255.25565,534
7559.74.0.0/1659.74.0.1 to 59.74.255.25459.74.255.25565,534
7659.75.0.0/1659.75.0.1 to 59.75.255.25459.75.255.25565,534
7759.76.0.0/1659.76.0.1 to 59.76.255.25459.76.255.25565,534
7859.77.0.0/1659.77.0.1 to 59.77.255.25459.77.255.25565,534
7959.78.0.0/1659.78.0.1 to 59.78.255.25459.78.255.25565,534
8059.79.0.0/1659.79.0.1 to 59.79.255.25459.79.255.25565,534
8159.80.0.0/1659.80.0.1 to 59.80.255.25459.80.255.25565,534
8259.81.0.0/1659.81.0.1 to 59.81.255.25459.81.255.25565,534
8359.82.0.0/1659.82.0.1 to 59.82.255.25459.82.255.25565,534
8459.83.0.0/1659.83.0.1 to 59.83.255.25459.83.255.25565,534
8559.84.0.0/1659.84.0.1 to 59.84.255.25459.84.255.25565,534
8659.85.0.0/1659.85.0.1 to 59.85.255.25459.85.255.25565,534
8759.86.0.0/1659.86.0.1 to 59.86.255.25459.86.255.25565,534
8859.87.0.0/1659.87.0.1 to 59.87.255.25459.87.255.25565,534
8959.88.0.0/1659.88.0.1 to 59.88.255.25459.88.255.25565,534
9059.89.0.0/1659.89.0.1 to 59.89.255.25459.89.255.25565,534
9159.90.0.0/1659.90.0.1 to 59.90.255.25459.90.255.25565,534
9259.91.0.0/1659.91.0.1 to 59.91.255.25459.91.255.25565,534
9359.92.0.0/1659.92.0.1 to 59.92.255.25459.92.255.25565,534
9459.93.0.0/1659.93.0.1 to 59.93.255.25459.93.255.25565,534
9559.94.0.0/1659.94.0.1 to 59.94.255.25459.94.255.25565,534
9659.95.0.0/1659.95.0.1 to 59.95.255.25459.95.255.25565,534
9759.96.0.0/1659.96.0.1 to 59.96.255.25459.96.255.25565,534
9859.97.0.0/1659.97.0.1 to 59.97.255.25459.97.255.25565,534
9959.98.0.0/1659.98.0.1 to 59.98.255.25459.98.255.25565,534
10059.99.0.0/1659.99.0.1 to 59.99.255.25459.99.255.25565,534
10159.100.0.0/1659.100.0.1 to 59.100.255.25459.100.255.25565,534
10259.101.0.0/1659.101.0.1 to 59.101.255.25459.101.255.25565,534
10359.102.0.0/1659.102.0.1 to 59.102.255.25459.102.255.25565,534
10459.103.0.0/1659.103.0.1 to 59.103.255.25459.103.255.25565,534
10559.104.0.0/1659.104.0.1 to 59.104.255.25459.104.255.25565,534
10659.105.0.0/1659.105.0.1 to 59.105.255.25459.105.255.25565,534
10759.106.0.0/1659.106.0.1 to 59.106.255.25459.106.255.25565,534
10859.107.0.0/1659.107.0.1 to 59.107.255.25459.107.255.25565,534
10959.108.0.0/1659.108.0.1 to 59.108.255.25459.108.255.25565,534
11059.109.0.0/1659.109.0.1 to 59.109.255.25459.109.255.25565,534
11159.110.0.0/1659.110.0.1 to 59.110.255.25459.110.255.25565,534
11259.111.0.0/1659.111.0.1 to 59.111.255.25459.111.255.25565,534
11359.112.0.0/1659.112.0.1 to 59.112.255.25459.112.255.25565,534
11459.113.0.0/1659.113.0.1 to 59.113.255.25459.113.255.25565,534
11559.114.0.0/1659.114.0.1 to 59.114.255.25459.114.255.25565,534
11659.115.0.0/1659.115.0.1 to 59.115.255.25459.115.255.25565,534
11759.116.0.0/1659.116.0.1 to 59.116.255.25459.116.255.25565,534
11859.117.0.0/1659.117.0.1 to 59.117.255.25459.117.255.25565,534
11959.118.0.0/1659.118.0.1 to 59.118.255.25459.118.255.25565,534
12059.119.0.0/1659.119.0.1 to 59.119.255.25459.119.255.25565,534
12159.120.0.0/1659.120.0.1 to 59.120.255.25459.120.255.25565,534
12259.121.0.0/1659.121.0.1 to 59.121.255.25459.121.255.25565,534
12359.122.0.0/1659.122.0.1 to 59.122.255.25459.122.255.25565,534
12459.123.0.0/1659.123.0.1 to 59.123.255.25459.123.255.25565,534
12559.124.0.0/1659.124.0.1 to 59.124.255.25459.124.255.25565,534
12659.125.0.0/1659.125.0.1 to 59.125.255.25459.125.255.25565,534
12759.126.0.0/1659.126.0.1 to 59.126.255.25459.126.255.25565,534
12859.127.0.0/1659.127.0.1 to 59.127.255.25459.127.255.25565,534

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