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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.

Network110.96.0.0/13
Usable hosts524,286
Subnet mask255.248.0.0
Addresses524,288
Network address
110.96.0.0
Broadcast address
110.103.255.255
First usable
110.96.0.1
Last usable
110.103.255.254
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 6E600000 · Integer 1851785216 to 1852309503
Reverse DNS zones
96.110.in-addr.arpa
97.110.in-addr.arpa
98.110.in-addr.arpa
99.110.in-addr.arpa
100.110.in-addr.arpa
101.110.in-addr.arpa
102.110.in-addr.arpa
103.110.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
Address01101110.01100000.00000000.00000000110.96.0.0
Subnet mask11111111.11111000.00000000.00000000255.248.0.0
Network01101110.01100000.00000000.00000000110.96.0.0
Broadcast01101110.01100111.11111111.11111111110.103.255.255
Split into smaller subnets/20
/14 (2)/15 (4)/16 (8)/17 (16)/18 (32)/19 (64)/20 (128)/21 (256)/22 (512)/23 (1,024)/24 (2,048)/25 (4,096)

110.96.0.0/13 makes 128 subnets of /20.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
1110.96.0.0/20110.96.0.1 to 110.96.15.254110.96.15.2554,094
2110.96.16.0/20110.96.16.1 to 110.96.31.254110.96.31.2554,094
3110.96.32.0/20110.96.32.1 to 110.96.47.254110.96.47.2554,094
4110.96.48.0/20110.96.48.1 to 110.96.63.254110.96.63.2554,094
5110.96.64.0/20110.96.64.1 to 110.96.79.254110.96.79.2554,094
6110.96.80.0/20110.96.80.1 to 110.96.95.254110.96.95.2554,094
7110.96.96.0/20110.96.96.1 to 110.96.111.254110.96.111.2554,094
8110.96.112.0/20110.96.112.1 to 110.96.127.254110.96.127.2554,094
9110.96.128.0/20110.96.128.1 to 110.96.143.254110.96.143.2554,094
10110.96.144.0/20110.96.144.1 to 110.96.159.254110.96.159.2554,094
11110.96.160.0/20110.96.160.1 to 110.96.175.254110.96.175.2554,094
12110.96.176.0/20110.96.176.1 to 110.96.191.254110.96.191.2554,094
13110.96.192.0/20110.96.192.1 to 110.96.207.254110.96.207.2554,094
14110.96.208.0/20110.96.208.1 to 110.96.223.254110.96.223.2554,094
15110.96.224.0/20110.96.224.1 to 110.96.239.254110.96.239.2554,094
16110.96.240.0/20110.96.240.1 to 110.96.255.254110.96.255.2554,094
17110.97.0.0/20110.97.0.1 to 110.97.15.254110.97.15.2554,094
18110.97.16.0/20110.97.16.1 to 110.97.31.254110.97.31.2554,094
19110.97.32.0/20110.97.32.1 to 110.97.47.254110.97.47.2554,094
20110.97.48.0/20110.97.48.1 to 110.97.63.254110.97.63.2554,094
21110.97.64.0/20110.97.64.1 to 110.97.79.254110.97.79.2554,094
22110.97.80.0/20110.97.80.1 to 110.97.95.254110.97.95.2554,094
23110.97.96.0/20110.97.96.1 to 110.97.111.254110.97.111.2554,094
24110.97.112.0/20110.97.112.1 to 110.97.127.254110.97.127.2554,094
25110.97.128.0/20110.97.128.1 to 110.97.143.254110.97.143.2554,094
26110.97.144.0/20110.97.144.1 to 110.97.159.254110.97.159.2554,094
27110.97.160.0/20110.97.160.1 to 110.97.175.254110.97.175.2554,094
28110.97.176.0/20110.97.176.1 to 110.97.191.254110.97.191.2554,094
29110.97.192.0/20110.97.192.1 to 110.97.207.254110.97.207.2554,094
30110.97.208.0/20110.97.208.1 to 110.97.223.254110.97.223.2554,094
31110.97.224.0/20110.97.224.1 to 110.97.239.254110.97.239.2554,094
32110.97.240.0/20110.97.240.1 to 110.97.255.254110.97.255.2554,094
33110.98.0.0/20110.98.0.1 to 110.98.15.254110.98.15.2554,094
34110.98.16.0/20110.98.16.1 to 110.98.31.254110.98.31.2554,094
35110.98.32.0/20110.98.32.1 to 110.98.47.254110.98.47.2554,094
36110.98.48.0/20110.98.48.1 to 110.98.63.254110.98.63.2554,094
37110.98.64.0/20110.98.64.1 to 110.98.79.254110.98.79.2554,094
38110.98.80.0/20110.98.80.1 to 110.98.95.254110.98.95.2554,094
39110.98.96.0/20110.98.96.1 to 110.98.111.254110.98.111.2554,094
40110.98.112.0/20110.98.112.1 to 110.98.127.254110.98.127.2554,094
41110.98.128.0/20110.98.128.1 to 110.98.143.254110.98.143.2554,094
42110.98.144.0/20110.98.144.1 to 110.98.159.254110.98.159.2554,094
43110.98.160.0/20110.98.160.1 to 110.98.175.254110.98.175.2554,094
44110.98.176.0/20110.98.176.1 to 110.98.191.254110.98.191.2554,094
45110.98.192.0/20110.98.192.1 to 110.98.207.254110.98.207.2554,094
46110.98.208.0/20110.98.208.1 to 110.98.223.254110.98.223.2554,094
47110.98.224.0/20110.98.224.1 to 110.98.239.254110.98.239.2554,094
48110.98.240.0/20110.98.240.1 to 110.98.255.254110.98.255.2554,094
49110.99.0.0/20110.99.0.1 to 110.99.15.254110.99.15.2554,094
50110.99.16.0/20110.99.16.1 to 110.99.31.254110.99.31.2554,094
51110.99.32.0/20110.99.32.1 to 110.99.47.254110.99.47.2554,094
52110.99.48.0/20110.99.48.1 to 110.99.63.254110.99.63.2554,094
53110.99.64.0/20110.99.64.1 to 110.99.79.254110.99.79.2554,094
54110.99.80.0/20110.99.80.1 to 110.99.95.254110.99.95.2554,094
55110.99.96.0/20110.99.96.1 to 110.99.111.254110.99.111.2554,094
56110.99.112.0/20110.99.112.1 to 110.99.127.254110.99.127.2554,094
57110.99.128.0/20110.99.128.1 to 110.99.143.254110.99.143.2554,094
58110.99.144.0/20110.99.144.1 to 110.99.159.254110.99.159.2554,094
59110.99.160.0/20110.99.160.1 to 110.99.175.254110.99.175.2554,094
60110.99.176.0/20110.99.176.1 to 110.99.191.254110.99.191.2554,094
61110.99.192.0/20110.99.192.1 to 110.99.207.254110.99.207.2554,094
62110.99.208.0/20110.99.208.1 to 110.99.223.254110.99.223.2554,094
63110.99.224.0/20110.99.224.1 to 110.99.239.254110.99.239.2554,094
64110.99.240.0/20110.99.240.1 to 110.99.255.254110.99.255.2554,094
65110.100.0.0/20110.100.0.1 to 110.100.15.254110.100.15.2554,094
66110.100.16.0/20110.100.16.1 to 110.100.31.254110.100.31.2554,094
67110.100.32.0/20110.100.32.1 to 110.100.47.254110.100.47.2554,094
68110.100.48.0/20110.100.48.1 to 110.100.63.254110.100.63.2554,094
69110.100.64.0/20110.100.64.1 to 110.100.79.254110.100.79.2554,094
70110.100.80.0/20110.100.80.1 to 110.100.95.254110.100.95.2554,094
71110.100.96.0/20110.100.96.1 to 110.100.111.254110.100.111.2554,094
72110.100.112.0/20110.100.112.1 to 110.100.127.254110.100.127.2554,094
73110.100.128.0/20110.100.128.1 to 110.100.143.254110.100.143.2554,094
74110.100.144.0/20110.100.144.1 to 110.100.159.254110.100.159.2554,094
75110.100.160.0/20110.100.160.1 to 110.100.175.254110.100.175.2554,094
76110.100.176.0/20110.100.176.1 to 110.100.191.254110.100.191.2554,094
77110.100.192.0/20110.100.192.1 to 110.100.207.254110.100.207.2554,094
78110.100.208.0/20110.100.208.1 to 110.100.223.254110.100.223.2554,094
79110.100.224.0/20110.100.224.1 to 110.100.239.254110.100.239.2554,094
80110.100.240.0/20110.100.240.1 to 110.100.255.254110.100.255.2554,094
81110.101.0.0/20110.101.0.1 to 110.101.15.254110.101.15.2554,094
82110.101.16.0/20110.101.16.1 to 110.101.31.254110.101.31.2554,094
83110.101.32.0/20110.101.32.1 to 110.101.47.254110.101.47.2554,094
84110.101.48.0/20110.101.48.1 to 110.101.63.254110.101.63.2554,094
85110.101.64.0/20110.101.64.1 to 110.101.79.254110.101.79.2554,094
86110.101.80.0/20110.101.80.1 to 110.101.95.254110.101.95.2554,094
87110.101.96.0/20110.101.96.1 to 110.101.111.254110.101.111.2554,094
88110.101.112.0/20110.101.112.1 to 110.101.127.254110.101.127.2554,094
89110.101.128.0/20110.101.128.1 to 110.101.143.254110.101.143.2554,094
90110.101.144.0/20110.101.144.1 to 110.101.159.254110.101.159.2554,094
91110.101.160.0/20110.101.160.1 to 110.101.175.254110.101.175.2554,094
92110.101.176.0/20110.101.176.1 to 110.101.191.254110.101.191.2554,094
93110.101.192.0/20110.101.192.1 to 110.101.207.254110.101.207.2554,094
94110.101.208.0/20110.101.208.1 to 110.101.223.254110.101.223.2554,094
95110.101.224.0/20110.101.224.1 to 110.101.239.254110.101.239.2554,094
96110.101.240.0/20110.101.240.1 to 110.101.255.254110.101.255.2554,094
97110.102.0.0/20110.102.0.1 to 110.102.15.254110.102.15.2554,094
98110.102.16.0/20110.102.16.1 to 110.102.31.254110.102.31.2554,094
99110.102.32.0/20110.102.32.1 to 110.102.47.254110.102.47.2554,094
100110.102.48.0/20110.102.48.1 to 110.102.63.254110.102.63.2554,094
101110.102.64.0/20110.102.64.1 to 110.102.79.254110.102.79.2554,094
102110.102.80.0/20110.102.80.1 to 110.102.95.254110.102.95.2554,094
103110.102.96.0/20110.102.96.1 to 110.102.111.254110.102.111.2554,094
104110.102.112.0/20110.102.112.1 to 110.102.127.254110.102.127.2554,094
105110.102.128.0/20110.102.128.1 to 110.102.143.254110.102.143.2554,094
106110.102.144.0/20110.102.144.1 to 110.102.159.254110.102.159.2554,094
107110.102.160.0/20110.102.160.1 to 110.102.175.254110.102.175.2554,094
108110.102.176.0/20110.102.176.1 to 110.102.191.254110.102.191.2554,094
109110.102.192.0/20110.102.192.1 to 110.102.207.254110.102.207.2554,094
110110.102.208.0/20110.102.208.1 to 110.102.223.254110.102.223.2554,094
111110.102.224.0/20110.102.224.1 to 110.102.239.254110.102.239.2554,094
112110.102.240.0/20110.102.240.1 to 110.102.255.254110.102.255.2554,094
113110.103.0.0/20110.103.0.1 to 110.103.15.254110.103.15.2554,094
114110.103.16.0/20110.103.16.1 to 110.103.31.254110.103.31.2554,094
115110.103.32.0/20110.103.32.1 to 110.103.47.254110.103.47.2554,094
116110.103.48.0/20110.103.48.1 to 110.103.63.254110.103.63.2554,094
117110.103.64.0/20110.103.64.1 to 110.103.79.254110.103.79.2554,094
118110.103.80.0/20110.103.80.1 to 110.103.95.254110.103.95.2554,094
119110.103.96.0/20110.103.96.1 to 110.103.111.254110.103.111.2554,094
120110.103.112.0/20110.103.112.1 to 110.103.127.254110.103.127.2554,094
121110.103.128.0/20110.103.128.1 to 110.103.143.254110.103.143.2554,094
122110.103.144.0/20110.103.144.1 to 110.103.159.254110.103.159.2554,094
123110.103.160.0/20110.103.160.1 to 110.103.175.254110.103.175.2554,094
124110.103.176.0/20110.103.176.1 to 110.103.191.254110.103.191.2554,094
125110.103.192.0/20110.103.192.1 to 110.103.207.254110.103.207.2554,094
126110.103.208.0/20110.103.208.1 to 110.103.223.254110.103.223.2554,094
127110.103.224.0/20110.103.224.1 to 110.103.239.254110.103.239.2554,094
128110.103.240.0/20110.103.240.1 to 110.103.255.254110.103.255.2554,094

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

About this tool

A network is written as an address and a prefix length, such as 192.168.1.0/24: the first 24 bits name the network and the rest number the devices on it. The calculator works out where the network starts and ends, how many devices it holds, its subnet and wildcard masks, and the reverse DNS zone to ask your provider for.

It also splits a network into equal smaller ones (one per VLAN or site), turns a range of addresses into the fewest CIDR blocks for a firewall rule, and lists every IPv4 prefix length and the common IPv6 ones in reference tables.

Common questions

Why are two addresses lost in every IPv4 subnet?

The first address names the network and the last is the broadcast address, so a /24 has 256 addresses but 254 for devices. A /31 (a link between two routers) and a /32 (one host) are the exceptions.

What size of IPv6 network should a LAN use?

Always /64. Devices pick their own address within it (SLAAC), which needs the full 64 bits. A site usually gets a /48 or /56 from its provider, which holds 65,536 or 256 LANs.

What is a wildcard mask?

The subnet mask turned inside out: 255.255.255.0 becomes 0.0.0.255. Cisco access lists and OSPF use it to say which bits must match.

Which ranges can I use inside an office?

IPv4: 10.0.0.0/8, 172.16.0.0/12 and 192.168.0.0/16. IPv6: unique local addresses from fd00::/8, though most networks use the public prefix from their provider.