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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.

Network196.136.0.0/15
Usable hosts131,070
Subnet mask255.254.0.0
Addresses131,072
Network address
196.136.0.0
Broadcast address
196.137.255.255
First usable
196.136.0.1
Last usable
196.137.255.254
Usable hosts
131,070 (131,072 less the network and broadcast addresses)
Subnet mask
255.254.0.0
Wildcard mask
0.1.255.255 (Cisco ACLs, OSPF)
Prefix length
/15
Type
Public public
Old class
C (default /24)
As numbers
Hex C4880000 · Integer 3297247232 to 3297378303
Reverse DNS zones
136.196.in-addr.arpa
137.196.in-addr.arpa
/15 is not on a 8-bit boundary, so it takes 2 /16 zones.
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address11000100.10001000.00000000.00000000196.136.0.0
Subnet mask11111111.11111110.00000000.00000000255.254.0.0
Network11000100.10001000.00000000.00000000196.136.0.0
Broadcast11000100.10001001.11111111.11111111196.137.255.255
Split into smaller subnets/22

196.136.0.0/15 makes 128 subnets of /22.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
1196.136.0.0/22196.136.0.1 to 196.136.3.254196.136.3.2551,022
2196.136.4.0/22196.136.4.1 to 196.136.7.254196.136.7.2551,022
3196.136.8.0/22196.136.8.1 to 196.136.11.254196.136.11.2551,022
4196.136.12.0/22196.136.12.1 to 196.136.15.254196.136.15.2551,022
5196.136.16.0/22196.136.16.1 to 196.136.19.254196.136.19.2551,022
6196.136.20.0/22196.136.20.1 to 196.136.23.254196.136.23.2551,022
7196.136.24.0/22196.136.24.1 to 196.136.27.254196.136.27.2551,022
8196.136.28.0/22196.136.28.1 to 196.136.31.254196.136.31.2551,022
9196.136.32.0/22196.136.32.1 to 196.136.35.254196.136.35.2551,022
10196.136.36.0/22196.136.36.1 to 196.136.39.254196.136.39.2551,022
11196.136.40.0/22196.136.40.1 to 196.136.43.254196.136.43.2551,022
12196.136.44.0/22196.136.44.1 to 196.136.47.254196.136.47.2551,022
13196.136.48.0/22196.136.48.1 to 196.136.51.254196.136.51.2551,022
14196.136.52.0/22196.136.52.1 to 196.136.55.254196.136.55.2551,022
15196.136.56.0/22196.136.56.1 to 196.136.59.254196.136.59.2551,022
16196.136.60.0/22196.136.60.1 to 196.136.63.254196.136.63.2551,022
17196.136.64.0/22196.136.64.1 to 196.136.67.254196.136.67.2551,022
18196.136.68.0/22196.136.68.1 to 196.136.71.254196.136.71.2551,022
19196.136.72.0/22196.136.72.1 to 196.136.75.254196.136.75.2551,022
20196.136.76.0/22196.136.76.1 to 196.136.79.254196.136.79.2551,022
21196.136.80.0/22196.136.80.1 to 196.136.83.254196.136.83.2551,022
22196.136.84.0/22196.136.84.1 to 196.136.87.254196.136.87.2551,022
23196.136.88.0/22196.136.88.1 to 196.136.91.254196.136.91.2551,022
24196.136.92.0/22196.136.92.1 to 196.136.95.254196.136.95.2551,022
25196.136.96.0/22196.136.96.1 to 196.136.99.254196.136.99.2551,022
26196.136.100.0/22196.136.100.1 to 196.136.103.254196.136.103.2551,022
27196.136.104.0/22196.136.104.1 to 196.136.107.254196.136.107.2551,022
28196.136.108.0/22196.136.108.1 to 196.136.111.254196.136.111.2551,022
29196.136.112.0/22196.136.112.1 to 196.136.115.254196.136.115.2551,022
30196.136.116.0/22196.136.116.1 to 196.136.119.254196.136.119.2551,022
31196.136.120.0/22196.136.120.1 to 196.136.123.254196.136.123.2551,022
32196.136.124.0/22196.136.124.1 to 196.136.127.254196.136.127.2551,022
33196.136.128.0/22196.136.128.1 to 196.136.131.254196.136.131.2551,022
34196.136.132.0/22196.136.132.1 to 196.136.135.254196.136.135.2551,022
35196.136.136.0/22196.136.136.1 to 196.136.139.254196.136.139.2551,022
36196.136.140.0/22196.136.140.1 to 196.136.143.254196.136.143.2551,022
37196.136.144.0/22196.136.144.1 to 196.136.147.254196.136.147.2551,022
38196.136.148.0/22196.136.148.1 to 196.136.151.254196.136.151.2551,022
39196.136.152.0/22196.136.152.1 to 196.136.155.254196.136.155.2551,022
40196.136.156.0/22196.136.156.1 to 196.136.159.254196.136.159.2551,022
41196.136.160.0/22196.136.160.1 to 196.136.163.254196.136.163.2551,022
42196.136.164.0/22196.136.164.1 to 196.136.167.254196.136.167.2551,022
43196.136.168.0/22196.136.168.1 to 196.136.171.254196.136.171.2551,022
44196.136.172.0/22196.136.172.1 to 196.136.175.254196.136.175.2551,022
45196.136.176.0/22196.136.176.1 to 196.136.179.254196.136.179.2551,022
46196.136.180.0/22196.136.180.1 to 196.136.183.254196.136.183.2551,022
47196.136.184.0/22196.136.184.1 to 196.136.187.254196.136.187.2551,022
48196.136.188.0/22196.136.188.1 to 196.136.191.254196.136.191.2551,022
49196.136.192.0/22196.136.192.1 to 196.136.195.254196.136.195.2551,022
50196.136.196.0/22196.136.196.1 to 196.136.199.254196.136.199.2551,022
51196.136.200.0/22196.136.200.1 to 196.136.203.254196.136.203.2551,022
52196.136.204.0/22196.136.204.1 to 196.136.207.254196.136.207.2551,022
53196.136.208.0/22196.136.208.1 to 196.136.211.254196.136.211.2551,022
54196.136.212.0/22196.136.212.1 to 196.136.215.254196.136.215.2551,022
55196.136.216.0/22196.136.216.1 to 196.136.219.254196.136.219.2551,022
56196.136.220.0/22196.136.220.1 to 196.136.223.254196.136.223.2551,022
57196.136.224.0/22196.136.224.1 to 196.136.227.254196.136.227.2551,022
58196.136.228.0/22196.136.228.1 to 196.136.231.254196.136.231.2551,022
59196.136.232.0/22196.136.232.1 to 196.136.235.254196.136.235.2551,022
60196.136.236.0/22196.136.236.1 to 196.136.239.254196.136.239.2551,022
61196.136.240.0/22196.136.240.1 to 196.136.243.254196.136.243.2551,022
62196.136.244.0/22196.136.244.1 to 196.136.247.254196.136.247.2551,022
63196.136.248.0/22196.136.248.1 to 196.136.251.254196.136.251.2551,022
64196.136.252.0/22196.136.252.1 to 196.136.255.254196.136.255.2551,022
65196.137.0.0/22196.137.0.1 to 196.137.3.254196.137.3.2551,022
66196.137.4.0/22196.137.4.1 to 196.137.7.254196.137.7.2551,022
67196.137.8.0/22196.137.8.1 to 196.137.11.254196.137.11.2551,022
68196.137.12.0/22196.137.12.1 to 196.137.15.254196.137.15.2551,022
69196.137.16.0/22196.137.16.1 to 196.137.19.254196.137.19.2551,022
70196.137.20.0/22196.137.20.1 to 196.137.23.254196.137.23.2551,022
71196.137.24.0/22196.137.24.1 to 196.137.27.254196.137.27.2551,022
72196.137.28.0/22196.137.28.1 to 196.137.31.254196.137.31.2551,022
73196.137.32.0/22196.137.32.1 to 196.137.35.254196.137.35.2551,022
74196.137.36.0/22196.137.36.1 to 196.137.39.254196.137.39.2551,022
75196.137.40.0/22196.137.40.1 to 196.137.43.254196.137.43.2551,022
76196.137.44.0/22196.137.44.1 to 196.137.47.254196.137.47.2551,022
77196.137.48.0/22196.137.48.1 to 196.137.51.254196.137.51.2551,022
78196.137.52.0/22196.137.52.1 to 196.137.55.254196.137.55.2551,022
79196.137.56.0/22196.137.56.1 to 196.137.59.254196.137.59.2551,022
80196.137.60.0/22196.137.60.1 to 196.137.63.254196.137.63.2551,022
81196.137.64.0/22196.137.64.1 to 196.137.67.254196.137.67.2551,022
82196.137.68.0/22196.137.68.1 to 196.137.71.254196.137.71.2551,022
83196.137.72.0/22196.137.72.1 to 196.137.75.254196.137.75.2551,022
84196.137.76.0/22196.137.76.1 to 196.137.79.254196.137.79.2551,022
85196.137.80.0/22196.137.80.1 to 196.137.83.254196.137.83.2551,022
86196.137.84.0/22196.137.84.1 to 196.137.87.254196.137.87.2551,022
87196.137.88.0/22196.137.88.1 to 196.137.91.254196.137.91.2551,022
88196.137.92.0/22196.137.92.1 to 196.137.95.254196.137.95.2551,022
89196.137.96.0/22196.137.96.1 to 196.137.99.254196.137.99.2551,022
90196.137.100.0/22196.137.100.1 to 196.137.103.254196.137.103.2551,022
91196.137.104.0/22196.137.104.1 to 196.137.107.254196.137.107.2551,022
92196.137.108.0/22196.137.108.1 to 196.137.111.254196.137.111.2551,022
93196.137.112.0/22196.137.112.1 to 196.137.115.254196.137.115.2551,022
94196.137.116.0/22196.137.116.1 to 196.137.119.254196.137.119.2551,022
95196.137.120.0/22196.137.120.1 to 196.137.123.254196.137.123.2551,022
96196.137.124.0/22196.137.124.1 to 196.137.127.254196.137.127.2551,022
97196.137.128.0/22196.137.128.1 to 196.137.131.254196.137.131.2551,022
98196.137.132.0/22196.137.132.1 to 196.137.135.254196.137.135.2551,022
99196.137.136.0/22196.137.136.1 to 196.137.139.254196.137.139.2551,022
100196.137.140.0/22196.137.140.1 to 196.137.143.254196.137.143.2551,022
101196.137.144.0/22196.137.144.1 to 196.137.147.254196.137.147.2551,022
102196.137.148.0/22196.137.148.1 to 196.137.151.254196.137.151.2551,022
103196.137.152.0/22196.137.152.1 to 196.137.155.254196.137.155.2551,022
104196.137.156.0/22196.137.156.1 to 196.137.159.254196.137.159.2551,022
105196.137.160.0/22196.137.160.1 to 196.137.163.254196.137.163.2551,022
106196.137.164.0/22196.137.164.1 to 196.137.167.254196.137.167.2551,022
107196.137.168.0/22196.137.168.1 to 196.137.171.254196.137.171.2551,022
108196.137.172.0/22196.137.172.1 to 196.137.175.254196.137.175.2551,022
109196.137.176.0/22196.137.176.1 to 196.137.179.254196.137.179.2551,022
110196.137.180.0/22196.137.180.1 to 196.137.183.254196.137.183.2551,022
111196.137.184.0/22196.137.184.1 to 196.137.187.254196.137.187.2551,022
112196.137.188.0/22196.137.188.1 to 196.137.191.254196.137.191.2551,022
113196.137.192.0/22196.137.192.1 to 196.137.195.254196.137.195.2551,022
114196.137.196.0/22196.137.196.1 to 196.137.199.254196.137.199.2551,022
115196.137.200.0/22196.137.200.1 to 196.137.203.254196.137.203.2551,022
116196.137.204.0/22196.137.204.1 to 196.137.207.254196.137.207.2551,022
117196.137.208.0/22196.137.208.1 to 196.137.211.254196.137.211.2551,022
118196.137.212.0/22196.137.212.1 to 196.137.215.254196.137.215.2551,022
119196.137.216.0/22196.137.216.1 to 196.137.219.254196.137.219.2551,022
120196.137.220.0/22196.137.220.1 to 196.137.223.254196.137.223.2551,022
121196.137.224.0/22196.137.224.1 to 196.137.227.254196.137.227.2551,022
122196.137.228.0/22196.137.228.1 to 196.137.231.254196.137.231.2551,022
123196.137.232.0/22196.137.232.1 to 196.137.235.254196.137.235.2551,022
124196.137.236.0/22196.137.236.1 to 196.137.239.254196.137.239.2551,022
125196.137.240.0/22196.137.240.1 to 196.137.243.254196.137.243.2551,022
126196.137.244.0/22196.137.244.1 to 196.137.247.254196.137.247.2551,022
127196.137.248.0/22196.137.248.1 to 196.137.251.254196.137.251.2551,022
128196.137.252.0/22196.137.252.1 to 196.137.255.254196.137.255.2551,022

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