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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.

Network183.192.0.0/10
Usable hosts4,194,302
Subnet mask255.192.0.0
Addresses4,194,304
Network address
183.192.0.0
Broadcast address
183.255.255.255
First usable
183.192.0.1
Last usable
183.255.255.254
Usable hosts
4,194,302 (4,194,304 less the network and broadcast addresses)
Subnet mask
255.192.0.0
Wildcard mask
0.63.255.255 (Cisco ACLs, OSPF)
Prefix length
/10
Type
Public public
Old class
B (default /16)
As numbers
Hex B7C00000 · Integer 3082813440 to 3087007743
Reverse DNS zones
192.183.in-addr.arpa
193.183.in-addr.arpa
194.183.in-addr.arpa
195.183.in-addr.arpa
196.183.in-addr.arpa
197.183.in-addr.arpa
198.183.in-addr.arpa
199.183.in-addr.arpa
200.183.in-addr.arpa
201.183.in-addr.arpa
202.183.in-addr.arpa
203.183.in-addr.arpa
204.183.in-addr.arpa
205.183.in-addr.arpa
206.183.in-addr.arpa
207.183.in-addr.arpa
and 48 more
/10 is not on a 8-bit boundary, so it takes 64 /16 zones.
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address10110111.11000000.00000000.00000000183.192.0.0
Subnet mask11111111.11000000.00000000.00000000255.192.0.0
Network10110111.11000000.00000000.00000000183.192.0.0
Broadcast10110111.11111111.11111111.11111111183.255.255.255
Split into smaller subnets/19
/11 (2)/12 (4)/13 (8)/14 (16)/15 (32)/16 (64)/17 (128)/18 (256)/19 (512)/20 (1,024)/21 (2,048)/22 (4,096)

183.192.0.0/10 makes 512 subnets of /19; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
1183.192.0.0/19183.192.0.1 to 183.192.31.254183.192.31.2558,190
2183.192.32.0/19183.192.32.1 to 183.192.63.254183.192.63.2558,190
3183.192.64.0/19183.192.64.1 to 183.192.95.254183.192.95.2558,190
4183.192.96.0/19183.192.96.1 to 183.192.127.254183.192.127.2558,190
5183.192.128.0/19183.192.128.1 to 183.192.159.254183.192.159.2558,190
6183.192.160.0/19183.192.160.1 to 183.192.191.254183.192.191.2558,190
7183.192.192.0/19183.192.192.1 to 183.192.223.254183.192.223.2558,190
8183.192.224.0/19183.192.224.1 to 183.192.255.254183.192.255.2558,190
9183.193.0.0/19183.193.0.1 to 183.193.31.254183.193.31.2558,190
10183.193.32.0/19183.193.32.1 to 183.193.63.254183.193.63.2558,190
11183.193.64.0/19183.193.64.1 to 183.193.95.254183.193.95.2558,190
12183.193.96.0/19183.193.96.1 to 183.193.127.254183.193.127.2558,190
13183.193.128.0/19183.193.128.1 to 183.193.159.254183.193.159.2558,190
14183.193.160.0/19183.193.160.1 to 183.193.191.254183.193.191.2558,190
15183.193.192.0/19183.193.192.1 to 183.193.223.254183.193.223.2558,190
16183.193.224.0/19183.193.224.1 to 183.193.255.254183.193.255.2558,190
17183.194.0.0/19183.194.0.1 to 183.194.31.254183.194.31.2558,190
18183.194.32.0/19183.194.32.1 to 183.194.63.254183.194.63.2558,190
19183.194.64.0/19183.194.64.1 to 183.194.95.254183.194.95.2558,190
20183.194.96.0/19183.194.96.1 to 183.194.127.254183.194.127.2558,190
21183.194.128.0/19183.194.128.1 to 183.194.159.254183.194.159.2558,190
22183.194.160.0/19183.194.160.1 to 183.194.191.254183.194.191.2558,190
23183.194.192.0/19183.194.192.1 to 183.194.223.254183.194.223.2558,190
24183.194.224.0/19183.194.224.1 to 183.194.255.254183.194.255.2558,190
25183.195.0.0/19183.195.0.1 to 183.195.31.254183.195.31.2558,190
26183.195.32.0/19183.195.32.1 to 183.195.63.254183.195.63.2558,190
27183.195.64.0/19183.195.64.1 to 183.195.95.254183.195.95.2558,190
28183.195.96.0/19183.195.96.1 to 183.195.127.254183.195.127.2558,190
29183.195.128.0/19183.195.128.1 to 183.195.159.254183.195.159.2558,190
30183.195.160.0/19183.195.160.1 to 183.195.191.254183.195.191.2558,190
31183.195.192.0/19183.195.192.1 to 183.195.223.254183.195.223.2558,190
32183.195.224.0/19183.195.224.1 to 183.195.255.254183.195.255.2558,190
33183.196.0.0/19183.196.0.1 to 183.196.31.254183.196.31.2558,190
34183.196.32.0/19183.196.32.1 to 183.196.63.254183.196.63.2558,190
35183.196.64.0/19183.196.64.1 to 183.196.95.254183.196.95.2558,190
36183.196.96.0/19183.196.96.1 to 183.196.127.254183.196.127.2558,190
37183.196.128.0/19183.196.128.1 to 183.196.159.254183.196.159.2558,190
38183.196.160.0/19183.196.160.1 to 183.196.191.254183.196.191.2558,190
39183.196.192.0/19183.196.192.1 to 183.196.223.254183.196.223.2558,190
40183.196.224.0/19183.196.224.1 to 183.196.255.254183.196.255.2558,190
41183.197.0.0/19183.197.0.1 to 183.197.31.254183.197.31.2558,190
42183.197.32.0/19183.197.32.1 to 183.197.63.254183.197.63.2558,190
43183.197.64.0/19183.197.64.1 to 183.197.95.254183.197.95.2558,190
44183.197.96.0/19183.197.96.1 to 183.197.127.254183.197.127.2558,190
45183.197.128.0/19183.197.128.1 to 183.197.159.254183.197.159.2558,190
46183.197.160.0/19183.197.160.1 to 183.197.191.254183.197.191.2558,190
47183.197.192.0/19183.197.192.1 to 183.197.223.254183.197.223.2558,190
48183.197.224.0/19183.197.224.1 to 183.197.255.254183.197.255.2558,190
49183.198.0.0/19183.198.0.1 to 183.198.31.254183.198.31.2558,190
50183.198.32.0/19183.198.32.1 to 183.198.63.254183.198.63.2558,190
51183.198.64.0/19183.198.64.1 to 183.198.95.254183.198.95.2558,190
52183.198.96.0/19183.198.96.1 to 183.198.127.254183.198.127.2558,190
53183.198.128.0/19183.198.128.1 to 183.198.159.254183.198.159.2558,190
54183.198.160.0/19183.198.160.1 to 183.198.191.254183.198.191.2558,190
55183.198.192.0/19183.198.192.1 to 183.198.223.254183.198.223.2558,190
56183.198.224.0/19183.198.224.1 to 183.198.255.254183.198.255.2558,190
57183.199.0.0/19183.199.0.1 to 183.199.31.254183.199.31.2558,190
58183.199.32.0/19183.199.32.1 to 183.199.63.254183.199.63.2558,190
59183.199.64.0/19183.199.64.1 to 183.199.95.254183.199.95.2558,190
60183.199.96.0/19183.199.96.1 to 183.199.127.254183.199.127.2558,190
61183.199.128.0/19183.199.128.1 to 183.199.159.254183.199.159.2558,190
62183.199.160.0/19183.199.160.1 to 183.199.191.254183.199.191.2558,190
63183.199.192.0/19183.199.192.1 to 183.199.223.254183.199.223.2558,190
64183.199.224.0/19183.199.224.1 to 183.199.255.254183.199.255.2558,190
65183.200.0.0/19183.200.0.1 to 183.200.31.254183.200.31.2558,190
66183.200.32.0/19183.200.32.1 to 183.200.63.254183.200.63.2558,190
67183.200.64.0/19183.200.64.1 to 183.200.95.254183.200.95.2558,190
68183.200.96.0/19183.200.96.1 to 183.200.127.254183.200.127.2558,190
69183.200.128.0/19183.200.128.1 to 183.200.159.254183.200.159.2558,190
70183.200.160.0/19183.200.160.1 to 183.200.191.254183.200.191.2558,190
71183.200.192.0/19183.200.192.1 to 183.200.223.254183.200.223.2558,190
72183.200.224.0/19183.200.224.1 to 183.200.255.254183.200.255.2558,190
73183.201.0.0/19183.201.0.1 to 183.201.31.254183.201.31.2558,190
74183.201.32.0/19183.201.32.1 to 183.201.63.254183.201.63.2558,190
75183.201.64.0/19183.201.64.1 to 183.201.95.254183.201.95.2558,190
76183.201.96.0/19183.201.96.1 to 183.201.127.254183.201.127.2558,190
77183.201.128.0/19183.201.128.1 to 183.201.159.254183.201.159.2558,190
78183.201.160.0/19183.201.160.1 to 183.201.191.254183.201.191.2558,190
79183.201.192.0/19183.201.192.1 to 183.201.223.254183.201.223.2558,190
80183.201.224.0/19183.201.224.1 to 183.201.255.254183.201.255.2558,190
81183.202.0.0/19183.202.0.1 to 183.202.31.254183.202.31.2558,190
82183.202.32.0/19183.202.32.1 to 183.202.63.254183.202.63.2558,190
83183.202.64.0/19183.202.64.1 to 183.202.95.254183.202.95.2558,190
84183.202.96.0/19183.202.96.1 to 183.202.127.254183.202.127.2558,190
85183.202.128.0/19183.202.128.1 to 183.202.159.254183.202.159.2558,190
86183.202.160.0/19183.202.160.1 to 183.202.191.254183.202.191.2558,190
87183.202.192.0/19183.202.192.1 to 183.202.223.254183.202.223.2558,190
88183.202.224.0/19183.202.224.1 to 183.202.255.254183.202.255.2558,190
89183.203.0.0/19183.203.0.1 to 183.203.31.254183.203.31.2558,190
90183.203.32.0/19183.203.32.1 to 183.203.63.254183.203.63.2558,190
91183.203.64.0/19183.203.64.1 to 183.203.95.254183.203.95.2558,190
92183.203.96.0/19183.203.96.1 to 183.203.127.254183.203.127.2558,190
93183.203.128.0/19183.203.128.1 to 183.203.159.254183.203.159.2558,190
94183.203.160.0/19183.203.160.1 to 183.203.191.254183.203.191.2558,190
95183.203.192.0/19183.203.192.1 to 183.203.223.254183.203.223.2558,190
96183.203.224.0/19183.203.224.1 to 183.203.255.254183.203.255.2558,190
97183.204.0.0/19183.204.0.1 to 183.204.31.254183.204.31.2558,190
98183.204.32.0/19183.204.32.1 to 183.204.63.254183.204.63.2558,190
99183.204.64.0/19183.204.64.1 to 183.204.95.254183.204.95.2558,190
100183.204.96.0/19183.204.96.1 to 183.204.127.254183.204.127.2558,190
101183.204.128.0/19183.204.128.1 to 183.204.159.254183.204.159.2558,190
102183.204.160.0/19183.204.160.1 to 183.204.191.254183.204.191.2558,190
103183.204.192.0/19183.204.192.1 to 183.204.223.254183.204.223.2558,190
104183.204.224.0/19183.204.224.1 to 183.204.255.254183.204.255.2558,190
105183.205.0.0/19183.205.0.1 to 183.205.31.254183.205.31.2558,190
106183.205.32.0/19183.205.32.1 to 183.205.63.254183.205.63.2558,190
107183.205.64.0/19183.205.64.1 to 183.205.95.254183.205.95.2558,190
108183.205.96.0/19183.205.96.1 to 183.205.127.254183.205.127.2558,190
109183.205.128.0/19183.205.128.1 to 183.205.159.254183.205.159.2558,190
110183.205.160.0/19183.205.160.1 to 183.205.191.254183.205.191.2558,190
111183.205.192.0/19183.205.192.1 to 183.205.223.254183.205.223.2558,190
112183.205.224.0/19183.205.224.1 to 183.205.255.254183.205.255.2558,190
113183.206.0.0/19183.206.0.1 to 183.206.31.254183.206.31.2558,190
114183.206.32.0/19183.206.32.1 to 183.206.63.254183.206.63.2558,190
115183.206.64.0/19183.206.64.1 to 183.206.95.254183.206.95.2558,190
116183.206.96.0/19183.206.96.1 to 183.206.127.254183.206.127.2558,190
117183.206.128.0/19183.206.128.1 to 183.206.159.254183.206.159.2558,190
118183.206.160.0/19183.206.160.1 to 183.206.191.254183.206.191.2558,190
119183.206.192.0/19183.206.192.1 to 183.206.223.254183.206.223.2558,190
120183.206.224.0/19183.206.224.1 to 183.206.255.254183.206.255.2558,190
121183.207.0.0/19183.207.0.1 to 183.207.31.254183.207.31.2558,190
122183.207.32.0/19183.207.32.1 to 183.207.63.254183.207.63.2558,190
123183.207.64.0/19183.207.64.1 to 183.207.95.254183.207.95.2558,190
124183.207.96.0/19183.207.96.1 to 183.207.127.254183.207.127.2558,190
125183.207.128.0/19183.207.128.1 to 183.207.159.254183.207.159.2558,190
126183.207.160.0/19183.207.160.1 to 183.207.191.254183.207.191.2558,190
127183.207.192.0/19183.207.192.1 to 183.207.223.254183.207.223.2558,190
128183.207.224.0/19183.207.224.1 to 183.207.255.254183.207.255.2558,190
129183.208.0.0/19183.208.0.1 to 183.208.31.254183.208.31.2558,190
130183.208.32.0/19183.208.32.1 to 183.208.63.254183.208.63.2558,190
131183.208.64.0/19183.208.64.1 to 183.208.95.254183.208.95.2558,190
132183.208.96.0/19183.208.96.1 to 183.208.127.254183.208.127.2558,190
133183.208.128.0/19183.208.128.1 to 183.208.159.254183.208.159.2558,190
134183.208.160.0/19183.208.160.1 to 183.208.191.254183.208.191.2558,190
135183.208.192.0/19183.208.192.1 to 183.208.223.254183.208.223.2558,190
136183.208.224.0/19183.208.224.1 to 183.208.255.254183.208.255.2558,190
137183.209.0.0/19183.209.0.1 to 183.209.31.254183.209.31.2558,190
138183.209.32.0/19183.209.32.1 to 183.209.63.254183.209.63.2558,190
139183.209.64.0/19183.209.64.1 to 183.209.95.254183.209.95.2558,190
140183.209.96.0/19183.209.96.1 to 183.209.127.254183.209.127.2558,190
141183.209.128.0/19183.209.128.1 to 183.209.159.254183.209.159.2558,190
142183.209.160.0/19183.209.160.1 to 183.209.191.254183.209.191.2558,190
143183.209.192.0/19183.209.192.1 to 183.209.223.254183.209.223.2558,190
144183.209.224.0/19183.209.224.1 to 183.209.255.254183.209.255.2558,190
145183.210.0.0/19183.210.0.1 to 183.210.31.254183.210.31.2558,190
146183.210.32.0/19183.210.32.1 to 183.210.63.254183.210.63.2558,190
147183.210.64.0/19183.210.64.1 to 183.210.95.254183.210.95.2558,190
148183.210.96.0/19183.210.96.1 to 183.210.127.254183.210.127.2558,190
149183.210.128.0/19183.210.128.1 to 183.210.159.254183.210.159.2558,190
150183.210.160.0/19183.210.160.1 to 183.210.191.254183.210.191.2558,190
151183.210.192.0/19183.210.192.1 to 183.210.223.254183.210.223.2558,190
152183.210.224.0/19183.210.224.1 to 183.210.255.254183.210.255.2558,190
153183.211.0.0/19183.211.0.1 to 183.211.31.254183.211.31.2558,190
154183.211.32.0/19183.211.32.1 to 183.211.63.254183.211.63.2558,190
155183.211.64.0/19183.211.64.1 to 183.211.95.254183.211.95.2558,190
156183.211.96.0/19183.211.96.1 to 183.211.127.254183.211.127.2558,190
157183.211.128.0/19183.211.128.1 to 183.211.159.254183.211.159.2558,190
158183.211.160.0/19183.211.160.1 to 183.211.191.254183.211.191.2558,190
159183.211.192.0/19183.211.192.1 to 183.211.223.254183.211.223.2558,190
160183.211.224.0/19183.211.224.1 to 183.211.255.254183.211.255.2558,190
161183.212.0.0/19183.212.0.1 to 183.212.31.254183.212.31.2558,190
162183.212.32.0/19183.212.32.1 to 183.212.63.254183.212.63.2558,190
163183.212.64.0/19183.212.64.1 to 183.212.95.254183.212.95.2558,190
164183.212.96.0/19183.212.96.1 to 183.212.127.254183.212.127.2558,190
165183.212.128.0/19183.212.128.1 to 183.212.159.254183.212.159.2558,190
166183.212.160.0/19183.212.160.1 to 183.212.191.254183.212.191.2558,190
167183.212.192.0/19183.212.192.1 to 183.212.223.254183.212.223.2558,190
168183.212.224.0/19183.212.224.1 to 183.212.255.254183.212.255.2558,190
169183.213.0.0/19183.213.0.1 to 183.213.31.254183.213.31.2558,190
170183.213.32.0/19183.213.32.1 to 183.213.63.254183.213.63.2558,190
171183.213.64.0/19183.213.64.1 to 183.213.95.254183.213.95.2558,190
172183.213.96.0/19183.213.96.1 to 183.213.127.254183.213.127.2558,190
173183.213.128.0/19183.213.128.1 to 183.213.159.254183.213.159.2558,190
174183.213.160.0/19183.213.160.1 to 183.213.191.254183.213.191.2558,190
175183.213.192.0/19183.213.192.1 to 183.213.223.254183.213.223.2558,190
176183.213.224.0/19183.213.224.1 to 183.213.255.254183.213.255.2558,190
177183.214.0.0/19183.214.0.1 to 183.214.31.254183.214.31.2558,190
178183.214.32.0/19183.214.32.1 to 183.214.63.254183.214.63.2558,190
179183.214.64.0/19183.214.64.1 to 183.214.95.254183.214.95.2558,190
180183.214.96.0/19183.214.96.1 to 183.214.127.254183.214.127.2558,190
181183.214.128.0/19183.214.128.1 to 183.214.159.254183.214.159.2558,190
182183.214.160.0/19183.214.160.1 to 183.214.191.254183.214.191.2558,190
183183.214.192.0/19183.214.192.1 to 183.214.223.254183.214.223.2558,190
184183.214.224.0/19183.214.224.1 to 183.214.255.254183.214.255.2558,190
185183.215.0.0/19183.215.0.1 to 183.215.31.254183.215.31.2558,190
186183.215.32.0/19183.215.32.1 to 183.215.63.254183.215.63.2558,190
187183.215.64.0/19183.215.64.1 to 183.215.95.254183.215.95.2558,190
188183.215.96.0/19183.215.96.1 to 183.215.127.254183.215.127.2558,190
189183.215.128.0/19183.215.128.1 to 183.215.159.254183.215.159.2558,190
190183.215.160.0/19183.215.160.1 to 183.215.191.254183.215.191.2558,190
191183.215.192.0/19183.215.192.1 to 183.215.223.254183.215.223.2558,190
192183.215.224.0/19183.215.224.1 to 183.215.255.254183.215.255.2558,190
193183.216.0.0/19183.216.0.1 to 183.216.31.254183.216.31.2558,190
194183.216.32.0/19183.216.32.1 to 183.216.63.254183.216.63.2558,190
195183.216.64.0/19183.216.64.1 to 183.216.95.254183.216.95.2558,190
196183.216.96.0/19183.216.96.1 to 183.216.127.254183.216.127.2558,190
197183.216.128.0/19183.216.128.1 to 183.216.159.254183.216.159.2558,190
198183.216.160.0/19183.216.160.1 to 183.216.191.254183.216.191.2558,190
199183.216.192.0/19183.216.192.1 to 183.216.223.254183.216.223.2558,190
200183.216.224.0/19183.216.224.1 to 183.216.255.254183.216.255.2558,190
201183.217.0.0/19183.217.0.1 to 183.217.31.254183.217.31.2558,190
202183.217.32.0/19183.217.32.1 to 183.217.63.254183.217.63.2558,190
203183.217.64.0/19183.217.64.1 to 183.217.95.254183.217.95.2558,190
204183.217.96.0/19183.217.96.1 to 183.217.127.254183.217.127.2558,190
205183.217.128.0/19183.217.128.1 to 183.217.159.254183.217.159.2558,190
206183.217.160.0/19183.217.160.1 to 183.217.191.254183.217.191.2558,190
207183.217.192.0/19183.217.192.1 to 183.217.223.254183.217.223.2558,190
208183.217.224.0/19183.217.224.1 to 183.217.255.254183.217.255.2558,190
209183.218.0.0/19183.218.0.1 to 183.218.31.254183.218.31.2558,190
210183.218.32.0/19183.218.32.1 to 183.218.63.254183.218.63.2558,190
211183.218.64.0/19183.218.64.1 to 183.218.95.254183.218.95.2558,190
212183.218.96.0/19183.218.96.1 to 183.218.127.254183.218.127.2558,190
213183.218.128.0/19183.218.128.1 to 183.218.159.254183.218.159.2558,190
214183.218.160.0/19183.218.160.1 to 183.218.191.254183.218.191.2558,190
215183.218.192.0/19183.218.192.1 to 183.218.223.254183.218.223.2558,190
216183.218.224.0/19183.218.224.1 to 183.218.255.254183.218.255.2558,190
217183.219.0.0/19183.219.0.1 to 183.219.31.254183.219.31.2558,190
218183.219.32.0/19183.219.32.1 to 183.219.63.254183.219.63.2558,190
219183.219.64.0/19183.219.64.1 to 183.219.95.254183.219.95.2558,190
220183.219.96.0/19183.219.96.1 to 183.219.127.254183.219.127.2558,190
221183.219.128.0/19183.219.128.1 to 183.219.159.254183.219.159.2558,190
222183.219.160.0/19183.219.160.1 to 183.219.191.254183.219.191.2558,190
223183.219.192.0/19183.219.192.1 to 183.219.223.254183.219.223.2558,190
224183.219.224.0/19183.219.224.1 to 183.219.255.254183.219.255.2558,190
225183.220.0.0/19183.220.0.1 to 183.220.31.254183.220.31.2558,190
226183.220.32.0/19183.220.32.1 to 183.220.63.254183.220.63.2558,190
227183.220.64.0/19183.220.64.1 to 183.220.95.254183.220.95.2558,190
228183.220.96.0/19183.220.96.1 to 183.220.127.254183.220.127.2558,190
229183.220.128.0/19183.220.128.1 to 183.220.159.254183.220.159.2558,190
230183.220.160.0/19183.220.160.1 to 183.220.191.254183.220.191.2558,190
231183.220.192.0/19183.220.192.1 to 183.220.223.254183.220.223.2558,190
232183.220.224.0/19183.220.224.1 to 183.220.255.254183.220.255.2558,190
233183.221.0.0/19183.221.0.1 to 183.221.31.254183.221.31.2558,190
234183.221.32.0/19183.221.32.1 to 183.221.63.254183.221.63.2558,190
235183.221.64.0/19183.221.64.1 to 183.221.95.254183.221.95.2558,190
236183.221.96.0/19183.221.96.1 to 183.221.127.254183.221.127.2558,190
237183.221.128.0/19183.221.128.1 to 183.221.159.254183.221.159.2558,190
238183.221.160.0/19183.221.160.1 to 183.221.191.254183.221.191.2558,190
239183.221.192.0/19183.221.192.1 to 183.221.223.254183.221.223.2558,190
240183.221.224.0/19183.221.224.1 to 183.221.255.254183.221.255.2558,190
241183.222.0.0/19183.222.0.1 to 183.222.31.254183.222.31.2558,190
242183.222.32.0/19183.222.32.1 to 183.222.63.254183.222.63.2558,190
243183.222.64.0/19183.222.64.1 to 183.222.95.254183.222.95.2558,190
244183.222.96.0/19183.222.96.1 to 183.222.127.254183.222.127.2558,190
245183.222.128.0/19183.222.128.1 to 183.222.159.254183.222.159.2558,190
246183.222.160.0/19183.222.160.1 to 183.222.191.254183.222.191.2558,190
247183.222.192.0/19183.222.192.1 to 183.222.223.254183.222.223.2558,190
248183.222.224.0/19183.222.224.1 to 183.222.255.254183.222.255.2558,190
249183.223.0.0/19183.223.0.1 to 183.223.31.254183.223.31.2558,190
250183.223.32.0/19183.223.32.1 to 183.223.63.254183.223.63.2558,190
251183.223.64.0/19183.223.64.1 to 183.223.95.254183.223.95.2558,190
252183.223.96.0/19183.223.96.1 to 183.223.127.254183.223.127.2558,190
253183.223.128.0/19183.223.128.1 to 183.223.159.254183.223.159.2558,190
254183.223.160.0/19183.223.160.1 to 183.223.191.254183.223.191.2558,190
255183.223.192.0/19183.223.192.1 to 183.223.223.254183.223.223.2558,190
256183.223.224.0/19183.223.224.1 to 183.223.255.254183.223.255.2558,190

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.