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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.

Network59.136.0.0/17
Usable hosts32,766
Subnet mask255.255.128.0
Addresses32,768
Network address
59.136.0.0
Broadcast address
59.136.127.255
First usable
59.136.0.1
Last usable
59.136.127.254
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 3B880000 · Integer 998768640 to 998801407
Reverse DNS zones
0.136.59.in-addr.arpa
1.136.59.in-addr.arpa
2.136.59.in-addr.arpa
3.136.59.in-addr.arpa
4.136.59.in-addr.arpa
5.136.59.in-addr.arpa
6.136.59.in-addr.arpa
7.136.59.in-addr.arpa
8.136.59.in-addr.arpa
9.136.59.in-addr.arpa
10.136.59.in-addr.arpa
11.136.59.in-addr.arpa
12.136.59.in-addr.arpa
13.136.59.in-addr.arpa
14.136.59.in-addr.arpa
15.136.59.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
Address00111011.10001000.00000000.0000000059.136.0.0
Subnet mask11111111.11111111.10000000.00000000255.255.128.0
Network00111011.10001000.00000000.0000000059.136.0.0
Broadcast00111011.10001000.01111111.1111111159.136.127.255
Split into smaller subnets/24

59.136.0.0/17 makes 128 subnets of /24.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
159.136.0.0/2459.136.0.1 to 59.136.0.25459.136.0.255254
259.136.1.0/2459.136.1.1 to 59.136.1.25459.136.1.255254
359.136.2.0/2459.136.2.1 to 59.136.2.25459.136.2.255254
459.136.3.0/2459.136.3.1 to 59.136.3.25459.136.3.255254
559.136.4.0/2459.136.4.1 to 59.136.4.25459.136.4.255254
659.136.5.0/2459.136.5.1 to 59.136.5.25459.136.5.255254
759.136.6.0/2459.136.6.1 to 59.136.6.25459.136.6.255254
859.136.7.0/2459.136.7.1 to 59.136.7.25459.136.7.255254
959.136.8.0/2459.136.8.1 to 59.136.8.25459.136.8.255254
1059.136.9.0/2459.136.9.1 to 59.136.9.25459.136.9.255254
1159.136.10.0/2459.136.10.1 to 59.136.10.25459.136.10.255254
1259.136.11.0/2459.136.11.1 to 59.136.11.25459.136.11.255254
1359.136.12.0/2459.136.12.1 to 59.136.12.25459.136.12.255254
1459.136.13.0/2459.136.13.1 to 59.136.13.25459.136.13.255254
1559.136.14.0/2459.136.14.1 to 59.136.14.25459.136.14.255254
1659.136.15.0/2459.136.15.1 to 59.136.15.25459.136.15.255254
1759.136.16.0/2459.136.16.1 to 59.136.16.25459.136.16.255254
1859.136.17.0/2459.136.17.1 to 59.136.17.25459.136.17.255254
1959.136.18.0/2459.136.18.1 to 59.136.18.25459.136.18.255254
2059.136.19.0/2459.136.19.1 to 59.136.19.25459.136.19.255254
2159.136.20.0/2459.136.20.1 to 59.136.20.25459.136.20.255254
2259.136.21.0/2459.136.21.1 to 59.136.21.25459.136.21.255254
2359.136.22.0/2459.136.22.1 to 59.136.22.25459.136.22.255254
2459.136.23.0/2459.136.23.1 to 59.136.23.25459.136.23.255254
2559.136.24.0/2459.136.24.1 to 59.136.24.25459.136.24.255254
2659.136.25.0/2459.136.25.1 to 59.136.25.25459.136.25.255254
2759.136.26.0/2459.136.26.1 to 59.136.26.25459.136.26.255254
2859.136.27.0/2459.136.27.1 to 59.136.27.25459.136.27.255254
2959.136.28.0/2459.136.28.1 to 59.136.28.25459.136.28.255254
3059.136.29.0/2459.136.29.1 to 59.136.29.25459.136.29.255254
3159.136.30.0/2459.136.30.1 to 59.136.30.25459.136.30.255254
3259.136.31.0/2459.136.31.1 to 59.136.31.25459.136.31.255254
3359.136.32.0/2459.136.32.1 to 59.136.32.25459.136.32.255254
3459.136.33.0/2459.136.33.1 to 59.136.33.25459.136.33.255254
3559.136.34.0/2459.136.34.1 to 59.136.34.25459.136.34.255254
3659.136.35.0/2459.136.35.1 to 59.136.35.25459.136.35.255254
3759.136.36.0/2459.136.36.1 to 59.136.36.25459.136.36.255254
3859.136.37.0/2459.136.37.1 to 59.136.37.25459.136.37.255254
3959.136.38.0/2459.136.38.1 to 59.136.38.25459.136.38.255254
4059.136.39.0/2459.136.39.1 to 59.136.39.25459.136.39.255254
4159.136.40.0/2459.136.40.1 to 59.136.40.25459.136.40.255254
4259.136.41.0/2459.136.41.1 to 59.136.41.25459.136.41.255254
4359.136.42.0/2459.136.42.1 to 59.136.42.25459.136.42.255254
4459.136.43.0/2459.136.43.1 to 59.136.43.25459.136.43.255254
4559.136.44.0/2459.136.44.1 to 59.136.44.25459.136.44.255254
4659.136.45.0/2459.136.45.1 to 59.136.45.25459.136.45.255254
4759.136.46.0/2459.136.46.1 to 59.136.46.25459.136.46.255254
4859.136.47.0/2459.136.47.1 to 59.136.47.25459.136.47.255254
4959.136.48.0/2459.136.48.1 to 59.136.48.25459.136.48.255254
5059.136.49.0/2459.136.49.1 to 59.136.49.25459.136.49.255254
5159.136.50.0/2459.136.50.1 to 59.136.50.25459.136.50.255254
5259.136.51.0/2459.136.51.1 to 59.136.51.25459.136.51.255254
5359.136.52.0/2459.136.52.1 to 59.136.52.25459.136.52.255254
5459.136.53.0/2459.136.53.1 to 59.136.53.25459.136.53.255254
5559.136.54.0/2459.136.54.1 to 59.136.54.25459.136.54.255254
5659.136.55.0/2459.136.55.1 to 59.136.55.25459.136.55.255254
5759.136.56.0/2459.136.56.1 to 59.136.56.25459.136.56.255254
5859.136.57.0/2459.136.57.1 to 59.136.57.25459.136.57.255254
5959.136.58.0/2459.136.58.1 to 59.136.58.25459.136.58.255254
6059.136.59.0/2459.136.59.1 to 59.136.59.25459.136.59.255254
6159.136.60.0/2459.136.60.1 to 59.136.60.25459.136.60.255254
6259.136.61.0/2459.136.61.1 to 59.136.61.25459.136.61.255254
6359.136.62.0/2459.136.62.1 to 59.136.62.25459.136.62.255254
6459.136.63.0/2459.136.63.1 to 59.136.63.25459.136.63.255254
6559.136.64.0/2459.136.64.1 to 59.136.64.25459.136.64.255254
6659.136.65.0/2459.136.65.1 to 59.136.65.25459.136.65.255254
6759.136.66.0/2459.136.66.1 to 59.136.66.25459.136.66.255254
6859.136.67.0/2459.136.67.1 to 59.136.67.25459.136.67.255254
6959.136.68.0/2459.136.68.1 to 59.136.68.25459.136.68.255254
7059.136.69.0/2459.136.69.1 to 59.136.69.25459.136.69.255254
7159.136.70.0/2459.136.70.1 to 59.136.70.25459.136.70.255254
7259.136.71.0/2459.136.71.1 to 59.136.71.25459.136.71.255254
7359.136.72.0/2459.136.72.1 to 59.136.72.25459.136.72.255254
7459.136.73.0/2459.136.73.1 to 59.136.73.25459.136.73.255254
7559.136.74.0/2459.136.74.1 to 59.136.74.25459.136.74.255254
7659.136.75.0/2459.136.75.1 to 59.136.75.25459.136.75.255254
7759.136.76.0/2459.136.76.1 to 59.136.76.25459.136.76.255254
7859.136.77.0/2459.136.77.1 to 59.136.77.25459.136.77.255254
7959.136.78.0/2459.136.78.1 to 59.136.78.25459.136.78.255254
8059.136.79.0/2459.136.79.1 to 59.136.79.25459.136.79.255254
8159.136.80.0/2459.136.80.1 to 59.136.80.25459.136.80.255254
8259.136.81.0/2459.136.81.1 to 59.136.81.25459.136.81.255254
8359.136.82.0/2459.136.82.1 to 59.136.82.25459.136.82.255254
8459.136.83.0/2459.136.83.1 to 59.136.83.25459.136.83.255254
8559.136.84.0/2459.136.84.1 to 59.136.84.25459.136.84.255254
8659.136.85.0/2459.136.85.1 to 59.136.85.25459.136.85.255254
8759.136.86.0/2459.136.86.1 to 59.136.86.25459.136.86.255254
8859.136.87.0/2459.136.87.1 to 59.136.87.25459.136.87.255254
8959.136.88.0/2459.136.88.1 to 59.136.88.25459.136.88.255254
9059.136.89.0/2459.136.89.1 to 59.136.89.25459.136.89.255254
9159.136.90.0/2459.136.90.1 to 59.136.90.25459.136.90.255254
9259.136.91.0/2459.136.91.1 to 59.136.91.25459.136.91.255254
9359.136.92.0/2459.136.92.1 to 59.136.92.25459.136.92.255254
9459.136.93.0/2459.136.93.1 to 59.136.93.25459.136.93.255254
9559.136.94.0/2459.136.94.1 to 59.136.94.25459.136.94.255254
9659.136.95.0/2459.136.95.1 to 59.136.95.25459.136.95.255254
9759.136.96.0/2459.136.96.1 to 59.136.96.25459.136.96.255254
9859.136.97.0/2459.136.97.1 to 59.136.97.25459.136.97.255254
9959.136.98.0/2459.136.98.1 to 59.136.98.25459.136.98.255254
10059.136.99.0/2459.136.99.1 to 59.136.99.25459.136.99.255254
10159.136.100.0/2459.136.100.1 to 59.136.100.25459.136.100.255254
10259.136.101.0/2459.136.101.1 to 59.136.101.25459.136.101.255254
10359.136.102.0/2459.136.102.1 to 59.136.102.25459.136.102.255254
10459.136.103.0/2459.136.103.1 to 59.136.103.25459.136.103.255254
10559.136.104.0/2459.136.104.1 to 59.136.104.25459.136.104.255254
10659.136.105.0/2459.136.105.1 to 59.136.105.25459.136.105.255254
10759.136.106.0/2459.136.106.1 to 59.136.106.25459.136.106.255254
10859.136.107.0/2459.136.107.1 to 59.136.107.25459.136.107.255254
10959.136.108.0/2459.136.108.1 to 59.136.108.25459.136.108.255254
11059.136.109.0/2459.136.109.1 to 59.136.109.25459.136.109.255254
11159.136.110.0/2459.136.110.1 to 59.136.110.25459.136.110.255254
11259.136.111.0/2459.136.111.1 to 59.136.111.25459.136.111.255254
11359.136.112.0/2459.136.112.1 to 59.136.112.25459.136.112.255254
11459.136.113.0/2459.136.113.1 to 59.136.113.25459.136.113.255254
11559.136.114.0/2459.136.114.1 to 59.136.114.25459.136.114.255254
11659.136.115.0/2459.136.115.1 to 59.136.115.25459.136.115.255254
11759.136.116.0/2459.136.116.1 to 59.136.116.25459.136.116.255254
11859.136.117.0/2459.136.117.1 to 59.136.117.25459.136.117.255254
11959.136.118.0/2459.136.118.1 to 59.136.118.25459.136.118.255254
12059.136.119.0/2459.136.119.1 to 59.136.119.25459.136.119.255254
12159.136.120.0/2459.136.120.1 to 59.136.120.25459.136.120.255254
12259.136.121.0/2459.136.121.1 to 59.136.121.25459.136.121.255254
12359.136.122.0/2459.136.122.1 to 59.136.122.25459.136.122.255254
12459.136.123.0/2459.136.123.1 to 59.136.123.25459.136.123.255254
12559.136.124.0/2459.136.124.1 to 59.136.124.25459.136.124.255254
12659.136.125.0/2459.136.125.1 to 59.136.125.25459.136.125.255254
12759.136.126.0/2459.136.126.1 to 59.136.126.25459.136.126.255254
12859.136.127.0/2459.136.127.1 to 59.136.127.25459.136.127.255254

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