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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.

Network229.64.0.0/11
Usable hosts2,097,150
Subnet mask255.224.0.0
Addresses2,097,152
Network address
229.64.0.0
Broadcast address
229.95.255.255
First usable
229.64.0.1
Last usable
229.95.255.254
Usable hosts
2,097,150 (2,097,152 less the network and broadcast addresses)
Subnet mask
255.224.0.0
Wildcard mask
0.31.255.255 (Cisco ACLs, OSPF)
Prefix length
/11
Type
Multicast 224.0.0.0/4
One-to-many traffic, such as IPTV and routing protocols
Old class
D (multicast)
As numbers
Hex E5400000 · Integer 3846176768 to 3848273919
Reverse DNS zones
64.229.in-addr.arpa
65.229.in-addr.arpa
66.229.in-addr.arpa
67.229.in-addr.arpa
68.229.in-addr.arpa
69.229.in-addr.arpa
70.229.in-addr.arpa
71.229.in-addr.arpa
72.229.in-addr.arpa
73.229.in-addr.arpa
74.229.in-addr.arpa
75.229.in-addr.arpa
76.229.in-addr.arpa
77.229.in-addr.arpa
78.229.in-addr.arpa
79.229.in-addr.arpa
and 16 more
/11 is not on a 8-bit boundary, so it takes 32 /16 zones.
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address11100101.01000000.00000000.00000000229.64.0.0
Subnet mask11111111.11100000.00000000.00000000255.224.0.0
Network11100101.01000000.00000000.00000000229.64.0.0
Broadcast11100101.01011111.11111111.11111111229.95.255.255
Split into smaller subnets/18
/12 (2)/13 (4)/14 (8)/15 (16)/16 (32)/17 (64)/18 (128)/19 (256)/20 (512)/21 (1,024)/22 (2,048)/23 (4,096)

229.64.0.0/11 makes 128 subnets of /18.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
1229.64.0.0/18229.64.0.1 to 229.64.63.254229.64.63.25516,382
2229.64.64.0/18229.64.64.1 to 229.64.127.254229.64.127.25516,382
3229.64.128.0/18229.64.128.1 to 229.64.191.254229.64.191.25516,382
4229.64.192.0/18229.64.192.1 to 229.64.255.254229.64.255.25516,382
5229.65.0.0/18229.65.0.1 to 229.65.63.254229.65.63.25516,382
6229.65.64.0/18229.65.64.1 to 229.65.127.254229.65.127.25516,382
7229.65.128.0/18229.65.128.1 to 229.65.191.254229.65.191.25516,382
8229.65.192.0/18229.65.192.1 to 229.65.255.254229.65.255.25516,382
9229.66.0.0/18229.66.0.1 to 229.66.63.254229.66.63.25516,382
10229.66.64.0/18229.66.64.1 to 229.66.127.254229.66.127.25516,382
11229.66.128.0/18229.66.128.1 to 229.66.191.254229.66.191.25516,382
12229.66.192.0/18229.66.192.1 to 229.66.255.254229.66.255.25516,382
13229.67.0.0/18229.67.0.1 to 229.67.63.254229.67.63.25516,382
14229.67.64.0/18229.67.64.1 to 229.67.127.254229.67.127.25516,382
15229.67.128.0/18229.67.128.1 to 229.67.191.254229.67.191.25516,382
16229.67.192.0/18229.67.192.1 to 229.67.255.254229.67.255.25516,382
17229.68.0.0/18229.68.0.1 to 229.68.63.254229.68.63.25516,382
18229.68.64.0/18229.68.64.1 to 229.68.127.254229.68.127.25516,382
19229.68.128.0/18229.68.128.1 to 229.68.191.254229.68.191.25516,382
20229.68.192.0/18229.68.192.1 to 229.68.255.254229.68.255.25516,382
21229.69.0.0/18229.69.0.1 to 229.69.63.254229.69.63.25516,382
22229.69.64.0/18229.69.64.1 to 229.69.127.254229.69.127.25516,382
23229.69.128.0/18229.69.128.1 to 229.69.191.254229.69.191.25516,382
24229.69.192.0/18229.69.192.1 to 229.69.255.254229.69.255.25516,382
25229.70.0.0/18229.70.0.1 to 229.70.63.254229.70.63.25516,382
26229.70.64.0/18229.70.64.1 to 229.70.127.254229.70.127.25516,382
27229.70.128.0/18229.70.128.1 to 229.70.191.254229.70.191.25516,382
28229.70.192.0/18229.70.192.1 to 229.70.255.254229.70.255.25516,382
29229.71.0.0/18229.71.0.1 to 229.71.63.254229.71.63.25516,382
30229.71.64.0/18229.71.64.1 to 229.71.127.254229.71.127.25516,382
31229.71.128.0/18229.71.128.1 to 229.71.191.254229.71.191.25516,382
32229.71.192.0/18229.71.192.1 to 229.71.255.254229.71.255.25516,382
33229.72.0.0/18229.72.0.1 to 229.72.63.254229.72.63.25516,382
34229.72.64.0/18229.72.64.1 to 229.72.127.254229.72.127.25516,382
35229.72.128.0/18229.72.128.1 to 229.72.191.254229.72.191.25516,382
36229.72.192.0/18229.72.192.1 to 229.72.255.254229.72.255.25516,382
37229.73.0.0/18229.73.0.1 to 229.73.63.254229.73.63.25516,382
38229.73.64.0/18229.73.64.1 to 229.73.127.254229.73.127.25516,382
39229.73.128.0/18229.73.128.1 to 229.73.191.254229.73.191.25516,382
40229.73.192.0/18229.73.192.1 to 229.73.255.254229.73.255.25516,382
41229.74.0.0/18229.74.0.1 to 229.74.63.254229.74.63.25516,382
42229.74.64.0/18229.74.64.1 to 229.74.127.254229.74.127.25516,382
43229.74.128.0/18229.74.128.1 to 229.74.191.254229.74.191.25516,382
44229.74.192.0/18229.74.192.1 to 229.74.255.254229.74.255.25516,382
45229.75.0.0/18229.75.0.1 to 229.75.63.254229.75.63.25516,382
46229.75.64.0/18229.75.64.1 to 229.75.127.254229.75.127.25516,382
47229.75.128.0/18229.75.128.1 to 229.75.191.254229.75.191.25516,382
48229.75.192.0/18229.75.192.1 to 229.75.255.254229.75.255.25516,382
49229.76.0.0/18229.76.0.1 to 229.76.63.254229.76.63.25516,382
50229.76.64.0/18229.76.64.1 to 229.76.127.254229.76.127.25516,382
51229.76.128.0/18229.76.128.1 to 229.76.191.254229.76.191.25516,382
52229.76.192.0/18229.76.192.1 to 229.76.255.254229.76.255.25516,382
53229.77.0.0/18229.77.0.1 to 229.77.63.254229.77.63.25516,382
54229.77.64.0/18229.77.64.1 to 229.77.127.254229.77.127.25516,382
55229.77.128.0/18229.77.128.1 to 229.77.191.254229.77.191.25516,382
56229.77.192.0/18229.77.192.1 to 229.77.255.254229.77.255.25516,382
57229.78.0.0/18229.78.0.1 to 229.78.63.254229.78.63.25516,382
58229.78.64.0/18229.78.64.1 to 229.78.127.254229.78.127.25516,382
59229.78.128.0/18229.78.128.1 to 229.78.191.254229.78.191.25516,382
60229.78.192.0/18229.78.192.1 to 229.78.255.254229.78.255.25516,382
61229.79.0.0/18229.79.0.1 to 229.79.63.254229.79.63.25516,382
62229.79.64.0/18229.79.64.1 to 229.79.127.254229.79.127.25516,382
63229.79.128.0/18229.79.128.1 to 229.79.191.254229.79.191.25516,382
64229.79.192.0/18229.79.192.1 to 229.79.255.254229.79.255.25516,382
65229.80.0.0/18229.80.0.1 to 229.80.63.254229.80.63.25516,382
66229.80.64.0/18229.80.64.1 to 229.80.127.254229.80.127.25516,382
67229.80.128.0/18229.80.128.1 to 229.80.191.254229.80.191.25516,382
68229.80.192.0/18229.80.192.1 to 229.80.255.254229.80.255.25516,382
69229.81.0.0/18229.81.0.1 to 229.81.63.254229.81.63.25516,382
70229.81.64.0/18229.81.64.1 to 229.81.127.254229.81.127.25516,382
71229.81.128.0/18229.81.128.1 to 229.81.191.254229.81.191.25516,382
72229.81.192.0/18229.81.192.1 to 229.81.255.254229.81.255.25516,382
73229.82.0.0/18229.82.0.1 to 229.82.63.254229.82.63.25516,382
74229.82.64.0/18229.82.64.1 to 229.82.127.254229.82.127.25516,382
75229.82.128.0/18229.82.128.1 to 229.82.191.254229.82.191.25516,382
76229.82.192.0/18229.82.192.1 to 229.82.255.254229.82.255.25516,382
77229.83.0.0/18229.83.0.1 to 229.83.63.254229.83.63.25516,382
78229.83.64.0/18229.83.64.1 to 229.83.127.254229.83.127.25516,382
79229.83.128.0/18229.83.128.1 to 229.83.191.254229.83.191.25516,382
80229.83.192.0/18229.83.192.1 to 229.83.255.254229.83.255.25516,382
81229.84.0.0/18229.84.0.1 to 229.84.63.254229.84.63.25516,382
82229.84.64.0/18229.84.64.1 to 229.84.127.254229.84.127.25516,382
83229.84.128.0/18229.84.128.1 to 229.84.191.254229.84.191.25516,382
84229.84.192.0/18229.84.192.1 to 229.84.255.254229.84.255.25516,382
85229.85.0.0/18229.85.0.1 to 229.85.63.254229.85.63.25516,382
86229.85.64.0/18229.85.64.1 to 229.85.127.254229.85.127.25516,382
87229.85.128.0/18229.85.128.1 to 229.85.191.254229.85.191.25516,382
88229.85.192.0/18229.85.192.1 to 229.85.255.254229.85.255.25516,382
89229.86.0.0/18229.86.0.1 to 229.86.63.254229.86.63.25516,382
90229.86.64.0/18229.86.64.1 to 229.86.127.254229.86.127.25516,382
91229.86.128.0/18229.86.128.1 to 229.86.191.254229.86.191.25516,382
92229.86.192.0/18229.86.192.1 to 229.86.255.254229.86.255.25516,382
93229.87.0.0/18229.87.0.1 to 229.87.63.254229.87.63.25516,382
94229.87.64.0/18229.87.64.1 to 229.87.127.254229.87.127.25516,382
95229.87.128.0/18229.87.128.1 to 229.87.191.254229.87.191.25516,382
96229.87.192.0/18229.87.192.1 to 229.87.255.254229.87.255.25516,382
97229.88.0.0/18229.88.0.1 to 229.88.63.254229.88.63.25516,382
98229.88.64.0/18229.88.64.1 to 229.88.127.254229.88.127.25516,382
99229.88.128.0/18229.88.128.1 to 229.88.191.254229.88.191.25516,382
100229.88.192.0/18229.88.192.1 to 229.88.255.254229.88.255.25516,382
101229.89.0.0/18229.89.0.1 to 229.89.63.254229.89.63.25516,382
102229.89.64.0/18229.89.64.1 to 229.89.127.254229.89.127.25516,382
103229.89.128.0/18229.89.128.1 to 229.89.191.254229.89.191.25516,382
104229.89.192.0/18229.89.192.1 to 229.89.255.254229.89.255.25516,382
105229.90.0.0/18229.90.0.1 to 229.90.63.254229.90.63.25516,382
106229.90.64.0/18229.90.64.1 to 229.90.127.254229.90.127.25516,382
107229.90.128.0/18229.90.128.1 to 229.90.191.254229.90.191.25516,382
108229.90.192.0/18229.90.192.1 to 229.90.255.254229.90.255.25516,382
109229.91.0.0/18229.91.0.1 to 229.91.63.254229.91.63.25516,382
110229.91.64.0/18229.91.64.1 to 229.91.127.254229.91.127.25516,382
111229.91.128.0/18229.91.128.1 to 229.91.191.254229.91.191.25516,382
112229.91.192.0/18229.91.192.1 to 229.91.255.254229.91.255.25516,382
113229.92.0.0/18229.92.0.1 to 229.92.63.254229.92.63.25516,382
114229.92.64.0/18229.92.64.1 to 229.92.127.254229.92.127.25516,382
115229.92.128.0/18229.92.128.1 to 229.92.191.254229.92.191.25516,382
116229.92.192.0/18229.92.192.1 to 229.92.255.254229.92.255.25516,382
117229.93.0.0/18229.93.0.1 to 229.93.63.254229.93.63.25516,382
118229.93.64.0/18229.93.64.1 to 229.93.127.254229.93.127.25516,382
119229.93.128.0/18229.93.128.1 to 229.93.191.254229.93.191.25516,382
120229.93.192.0/18229.93.192.1 to 229.93.255.254229.93.255.25516,382
121229.94.0.0/18229.94.0.1 to 229.94.63.254229.94.63.25516,382
122229.94.64.0/18229.94.64.1 to 229.94.127.254229.94.127.25516,382
123229.94.128.0/18229.94.128.1 to 229.94.191.254229.94.191.25516,382
124229.94.192.0/18229.94.192.1 to 229.94.255.254229.94.255.25516,382
125229.95.0.0/18229.95.0.1 to 229.95.63.254229.95.63.25516,382
126229.95.64.0/18229.95.64.1 to 229.95.127.254229.95.127.25516,382
127229.95.128.0/18229.95.128.1 to 229.95.191.254229.95.191.25516,382
128229.95.192.0/18229.95.192.1 to 229.95.255.254229.95.255.25516,382

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.