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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.

Network229.2.52.0/22
Usable hosts1,022
Subnet mask255.255.252.0
Addresses1,024
Network address
229.2.52.0
Broadcast address
229.2.55.255
First usable
229.2.52.1
Last usable
229.2.55.254
Usable hosts
1,022 (1,024 less the network and broadcast addresses)
Subnet mask
255.255.252.0
Wildcard mask
0.0.3.255 (Cisco ACLs, OSPF)
Prefix length
/22
Type
Multicast 224.0.0.0/4
One-to-many traffic, such as IPTV and routing protocols
Old class
D (multicast)
As numbers
Hex E5023400 · Integer 3842126848 to 3842127871
Reverse DNS zones
52.2.229.in-addr.arpa
53.2.229.in-addr.arpa
54.2.229.in-addr.arpa
55.2.229.in-addr.arpa
/22 is not on a 8-bit boundary, so it takes 4 /24 zones.
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address11100101.00000010.00110100.00000000229.2.52.0
Subnet mask11111111.11111111.11111100.00000000255.255.252.0
Network11100101.00000010.00110100.00000000229.2.52.0
Broadcast11100101.00000010.00110111.11111111229.2.55.255
Split into smaller subnets/32
/23 (2)/24 (4)/25 (8)/26 (16)/27 (32)/28 (64)/29 (128)/30 (256)/31 (512)/32 (1,024)

229.2.52.0/22 makes 1,024 subnets of /32; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
1229.2.52.0/32229.2.52.0 to 229.2.52.0—1
2229.2.52.1/32229.2.52.1 to 229.2.52.1—1
3229.2.52.2/32229.2.52.2 to 229.2.52.2—1
4229.2.52.3/32229.2.52.3 to 229.2.52.3—1
5229.2.52.4/32229.2.52.4 to 229.2.52.4—1
6229.2.52.5/32229.2.52.5 to 229.2.52.5—1
7229.2.52.6/32229.2.52.6 to 229.2.52.6—1
8229.2.52.7/32229.2.52.7 to 229.2.52.7—1
9229.2.52.8/32229.2.52.8 to 229.2.52.8—1
10229.2.52.9/32229.2.52.9 to 229.2.52.9—1
11229.2.52.10/32229.2.52.10 to 229.2.52.10—1
12229.2.52.11/32229.2.52.11 to 229.2.52.11—1
13229.2.52.12/32229.2.52.12 to 229.2.52.12—1
14229.2.52.13/32229.2.52.13 to 229.2.52.13—1
15229.2.52.14/32229.2.52.14 to 229.2.52.14—1
16229.2.52.15/32229.2.52.15 to 229.2.52.15—1
17229.2.52.16/32229.2.52.16 to 229.2.52.16—1
18229.2.52.17/32229.2.52.17 to 229.2.52.17—1
19229.2.52.18/32229.2.52.18 to 229.2.52.18—1
20229.2.52.19/32229.2.52.19 to 229.2.52.19—1
21229.2.52.20/32229.2.52.20 to 229.2.52.20—1
22229.2.52.21/32229.2.52.21 to 229.2.52.21—1
23229.2.52.22/32229.2.52.22 to 229.2.52.22—1
24229.2.52.23/32229.2.52.23 to 229.2.52.23—1
25229.2.52.24/32229.2.52.24 to 229.2.52.24—1
26229.2.52.25/32229.2.52.25 to 229.2.52.25—1
27229.2.52.26/32229.2.52.26 to 229.2.52.26—1
28229.2.52.27/32229.2.52.27 to 229.2.52.27—1
29229.2.52.28/32229.2.52.28 to 229.2.52.28—1
30229.2.52.29/32229.2.52.29 to 229.2.52.29—1
31229.2.52.30/32229.2.52.30 to 229.2.52.30—1
32229.2.52.31/32229.2.52.31 to 229.2.52.31—1
33229.2.52.32/32229.2.52.32 to 229.2.52.32—1
34229.2.52.33/32229.2.52.33 to 229.2.52.33—1
35229.2.52.34/32229.2.52.34 to 229.2.52.34—1
36229.2.52.35/32229.2.52.35 to 229.2.52.35—1
37229.2.52.36/32229.2.52.36 to 229.2.52.36—1
38229.2.52.37/32229.2.52.37 to 229.2.52.37—1
39229.2.52.38/32229.2.52.38 to 229.2.52.38—1
40229.2.52.39/32229.2.52.39 to 229.2.52.39—1
41229.2.52.40/32229.2.52.40 to 229.2.52.40—1
42229.2.52.41/32229.2.52.41 to 229.2.52.41—1
43229.2.52.42/32229.2.52.42 to 229.2.52.42—1
44229.2.52.43/32229.2.52.43 to 229.2.52.43—1
45229.2.52.44/32229.2.52.44 to 229.2.52.44—1
46229.2.52.45/32229.2.52.45 to 229.2.52.45—1
47229.2.52.46/32229.2.52.46 to 229.2.52.46—1
48229.2.52.47/32229.2.52.47 to 229.2.52.47—1
49229.2.52.48/32229.2.52.48 to 229.2.52.48—1
50229.2.52.49/32229.2.52.49 to 229.2.52.49—1
51229.2.52.50/32229.2.52.50 to 229.2.52.50—1
52229.2.52.51/32229.2.52.51 to 229.2.52.51—1
53229.2.52.52/32229.2.52.52 to 229.2.52.52—1
54229.2.52.53/32229.2.52.53 to 229.2.52.53—1
55229.2.52.54/32229.2.52.54 to 229.2.52.54—1
56229.2.52.55/32229.2.52.55 to 229.2.52.55—1
57229.2.52.56/32229.2.52.56 to 229.2.52.56—1
58229.2.52.57/32229.2.52.57 to 229.2.52.57—1
59229.2.52.58/32229.2.52.58 to 229.2.52.58—1
60229.2.52.59/32229.2.52.59 to 229.2.52.59—1
61229.2.52.60/32229.2.52.60 to 229.2.52.60—1
62229.2.52.61/32229.2.52.61 to 229.2.52.61—1
63229.2.52.62/32229.2.52.62 to 229.2.52.62—1
64229.2.52.63/32229.2.52.63 to 229.2.52.63—1
65229.2.52.64/32229.2.52.64 to 229.2.52.64—1
66229.2.52.65/32229.2.52.65 to 229.2.52.65—1
67229.2.52.66/32229.2.52.66 to 229.2.52.66—1
68229.2.52.67/32229.2.52.67 to 229.2.52.67—1
69229.2.52.68/32229.2.52.68 to 229.2.52.68—1
70229.2.52.69/32229.2.52.69 to 229.2.52.69—1
71229.2.52.70/32229.2.52.70 to 229.2.52.70—1
72229.2.52.71/32229.2.52.71 to 229.2.52.71—1
73229.2.52.72/32229.2.52.72 to 229.2.52.72—1
74229.2.52.73/32229.2.52.73 to 229.2.52.73—1
75229.2.52.74/32229.2.52.74 to 229.2.52.74—1
76229.2.52.75/32229.2.52.75 to 229.2.52.75—1
77229.2.52.76/32229.2.52.76 to 229.2.52.76—1
78229.2.52.77/32229.2.52.77 to 229.2.52.77—1
79229.2.52.78/32229.2.52.78 to 229.2.52.78—1
80229.2.52.79/32229.2.52.79 to 229.2.52.79—1
81229.2.52.80/32229.2.52.80 to 229.2.52.80—1
82229.2.52.81/32229.2.52.81 to 229.2.52.81—1
83229.2.52.82/32229.2.52.82 to 229.2.52.82—1
84229.2.52.83/32229.2.52.83 to 229.2.52.83—1
85229.2.52.84/32229.2.52.84 to 229.2.52.84—1
86229.2.52.85/32229.2.52.85 to 229.2.52.85—1
87229.2.52.86/32229.2.52.86 to 229.2.52.86—1
88229.2.52.87/32229.2.52.87 to 229.2.52.87—1
89229.2.52.88/32229.2.52.88 to 229.2.52.88—1
90229.2.52.89/32229.2.52.89 to 229.2.52.89—1
91229.2.52.90/32229.2.52.90 to 229.2.52.90—1
92229.2.52.91/32229.2.52.91 to 229.2.52.91—1
93229.2.52.92/32229.2.52.92 to 229.2.52.92—1
94229.2.52.93/32229.2.52.93 to 229.2.52.93—1
95229.2.52.94/32229.2.52.94 to 229.2.52.94—1
96229.2.52.95/32229.2.52.95 to 229.2.52.95—1
97229.2.52.96/32229.2.52.96 to 229.2.52.96—1
98229.2.52.97/32229.2.52.97 to 229.2.52.97—1
99229.2.52.98/32229.2.52.98 to 229.2.52.98—1
100229.2.52.99/32229.2.52.99 to 229.2.52.99—1
101229.2.52.100/32229.2.52.100 to 229.2.52.100—1
102229.2.52.101/32229.2.52.101 to 229.2.52.101—1
103229.2.52.102/32229.2.52.102 to 229.2.52.102—1
104229.2.52.103/32229.2.52.103 to 229.2.52.103—1
105229.2.52.104/32229.2.52.104 to 229.2.52.104—1
106229.2.52.105/32229.2.52.105 to 229.2.52.105—1
107229.2.52.106/32229.2.52.106 to 229.2.52.106—1
108229.2.52.107/32229.2.52.107 to 229.2.52.107—1
109229.2.52.108/32229.2.52.108 to 229.2.52.108—1
110229.2.52.109/32229.2.52.109 to 229.2.52.109—1
111229.2.52.110/32229.2.52.110 to 229.2.52.110—1
112229.2.52.111/32229.2.52.111 to 229.2.52.111—1
113229.2.52.112/32229.2.52.112 to 229.2.52.112—1
114229.2.52.113/32229.2.52.113 to 229.2.52.113—1
115229.2.52.114/32229.2.52.114 to 229.2.52.114—1
116229.2.52.115/32229.2.52.115 to 229.2.52.115—1
117229.2.52.116/32229.2.52.116 to 229.2.52.116—1
118229.2.52.117/32229.2.52.117 to 229.2.52.117—1
119229.2.52.118/32229.2.52.118 to 229.2.52.118—1
120229.2.52.119/32229.2.52.119 to 229.2.52.119—1
121229.2.52.120/32229.2.52.120 to 229.2.52.120—1
122229.2.52.121/32229.2.52.121 to 229.2.52.121—1
123229.2.52.122/32229.2.52.122 to 229.2.52.122—1
124229.2.52.123/32229.2.52.123 to 229.2.52.123—1
125229.2.52.124/32229.2.52.124 to 229.2.52.124—1
126229.2.52.125/32229.2.52.125 to 229.2.52.125—1
127229.2.52.126/32229.2.52.126 to 229.2.52.126—1
128229.2.52.127/32229.2.52.127 to 229.2.52.127—1
129229.2.52.128/32229.2.52.128 to 229.2.52.128—1
130229.2.52.129/32229.2.52.129 to 229.2.52.129—1
131229.2.52.130/32229.2.52.130 to 229.2.52.130—1
132229.2.52.131/32229.2.52.131 to 229.2.52.131—1
133229.2.52.132/32229.2.52.132 to 229.2.52.132—1
134229.2.52.133/32229.2.52.133 to 229.2.52.133—1
135229.2.52.134/32229.2.52.134 to 229.2.52.134—1
136229.2.52.135/32229.2.52.135 to 229.2.52.135—1
137229.2.52.136/32229.2.52.136 to 229.2.52.136—1
138229.2.52.137/32229.2.52.137 to 229.2.52.137—1
139229.2.52.138/32229.2.52.138 to 229.2.52.138—1
140229.2.52.139/32229.2.52.139 to 229.2.52.139—1
141229.2.52.140/32229.2.52.140 to 229.2.52.140—1
142229.2.52.141/32229.2.52.141 to 229.2.52.141—1
143229.2.52.142/32229.2.52.142 to 229.2.52.142—1
144229.2.52.143/32229.2.52.143 to 229.2.52.143—1
145229.2.52.144/32229.2.52.144 to 229.2.52.144—1
146229.2.52.145/32229.2.52.145 to 229.2.52.145—1
147229.2.52.146/32229.2.52.146 to 229.2.52.146—1
148229.2.52.147/32229.2.52.147 to 229.2.52.147—1
149229.2.52.148/32229.2.52.148 to 229.2.52.148—1
150229.2.52.149/32229.2.52.149 to 229.2.52.149—1
151229.2.52.150/32229.2.52.150 to 229.2.52.150—1
152229.2.52.151/32229.2.52.151 to 229.2.52.151—1
153229.2.52.152/32229.2.52.152 to 229.2.52.152—1
154229.2.52.153/32229.2.52.153 to 229.2.52.153—1
155229.2.52.154/32229.2.52.154 to 229.2.52.154—1
156229.2.52.155/32229.2.52.155 to 229.2.52.155—1
157229.2.52.156/32229.2.52.156 to 229.2.52.156—1
158229.2.52.157/32229.2.52.157 to 229.2.52.157—1
159229.2.52.158/32229.2.52.158 to 229.2.52.158—1
160229.2.52.159/32229.2.52.159 to 229.2.52.159—1
161229.2.52.160/32229.2.52.160 to 229.2.52.160—1
162229.2.52.161/32229.2.52.161 to 229.2.52.161—1
163229.2.52.162/32229.2.52.162 to 229.2.52.162—1
164229.2.52.163/32229.2.52.163 to 229.2.52.163—1
165229.2.52.164/32229.2.52.164 to 229.2.52.164—1
166229.2.52.165/32229.2.52.165 to 229.2.52.165—1
167229.2.52.166/32229.2.52.166 to 229.2.52.166—1
168229.2.52.167/32229.2.52.167 to 229.2.52.167—1
169229.2.52.168/32229.2.52.168 to 229.2.52.168—1
170229.2.52.169/32229.2.52.169 to 229.2.52.169—1
171229.2.52.170/32229.2.52.170 to 229.2.52.170—1
172229.2.52.171/32229.2.52.171 to 229.2.52.171—1
173229.2.52.172/32229.2.52.172 to 229.2.52.172—1
174229.2.52.173/32229.2.52.173 to 229.2.52.173—1
175229.2.52.174/32229.2.52.174 to 229.2.52.174—1
176229.2.52.175/32229.2.52.175 to 229.2.52.175—1
177229.2.52.176/32229.2.52.176 to 229.2.52.176—1
178229.2.52.177/32229.2.52.177 to 229.2.52.177—1
179229.2.52.178/32229.2.52.178 to 229.2.52.178—1
180229.2.52.179/32229.2.52.179 to 229.2.52.179—1
181229.2.52.180/32229.2.52.180 to 229.2.52.180—1
182229.2.52.181/32229.2.52.181 to 229.2.52.181—1
183229.2.52.182/32229.2.52.182 to 229.2.52.182—1
184229.2.52.183/32229.2.52.183 to 229.2.52.183—1
185229.2.52.184/32229.2.52.184 to 229.2.52.184—1
186229.2.52.185/32229.2.52.185 to 229.2.52.185—1
187229.2.52.186/32229.2.52.186 to 229.2.52.186—1
188229.2.52.187/32229.2.52.187 to 229.2.52.187—1
189229.2.52.188/32229.2.52.188 to 229.2.52.188—1
190229.2.52.189/32229.2.52.189 to 229.2.52.189—1
191229.2.52.190/32229.2.52.190 to 229.2.52.190—1
192229.2.52.191/32229.2.52.191 to 229.2.52.191—1
193229.2.52.192/32229.2.52.192 to 229.2.52.192—1
194229.2.52.193/32229.2.52.193 to 229.2.52.193—1
195229.2.52.194/32229.2.52.194 to 229.2.52.194—1
196229.2.52.195/32229.2.52.195 to 229.2.52.195—1
197229.2.52.196/32229.2.52.196 to 229.2.52.196—1
198229.2.52.197/32229.2.52.197 to 229.2.52.197—1
199229.2.52.198/32229.2.52.198 to 229.2.52.198—1
200229.2.52.199/32229.2.52.199 to 229.2.52.199—1
201229.2.52.200/32229.2.52.200 to 229.2.52.200—1
202229.2.52.201/32229.2.52.201 to 229.2.52.201—1
203229.2.52.202/32229.2.52.202 to 229.2.52.202—1
204229.2.52.203/32229.2.52.203 to 229.2.52.203—1
205229.2.52.204/32229.2.52.204 to 229.2.52.204—1
206229.2.52.205/32229.2.52.205 to 229.2.52.205—1
207229.2.52.206/32229.2.52.206 to 229.2.52.206—1
208229.2.52.207/32229.2.52.207 to 229.2.52.207—1
209229.2.52.208/32229.2.52.208 to 229.2.52.208—1
210229.2.52.209/32229.2.52.209 to 229.2.52.209—1
211229.2.52.210/32229.2.52.210 to 229.2.52.210—1
212229.2.52.211/32229.2.52.211 to 229.2.52.211—1
213229.2.52.212/32229.2.52.212 to 229.2.52.212—1
214229.2.52.213/32229.2.52.213 to 229.2.52.213—1
215229.2.52.214/32229.2.52.214 to 229.2.52.214—1
216229.2.52.215/32229.2.52.215 to 229.2.52.215—1
217229.2.52.216/32229.2.52.216 to 229.2.52.216—1
218229.2.52.217/32229.2.52.217 to 229.2.52.217—1
219229.2.52.218/32229.2.52.218 to 229.2.52.218—1
220229.2.52.219/32229.2.52.219 to 229.2.52.219—1
221229.2.52.220/32229.2.52.220 to 229.2.52.220—1
222229.2.52.221/32229.2.52.221 to 229.2.52.221—1
223229.2.52.222/32229.2.52.222 to 229.2.52.222—1
224229.2.52.223/32229.2.52.223 to 229.2.52.223—1
225229.2.52.224/32229.2.52.224 to 229.2.52.224—1
226229.2.52.225/32229.2.52.225 to 229.2.52.225—1
227229.2.52.226/32229.2.52.226 to 229.2.52.226—1
228229.2.52.227/32229.2.52.227 to 229.2.52.227—1
229229.2.52.228/32229.2.52.228 to 229.2.52.228—1
230229.2.52.229/32229.2.52.229 to 229.2.52.229—1
231229.2.52.230/32229.2.52.230 to 229.2.52.230—1
232229.2.52.231/32229.2.52.231 to 229.2.52.231—1
233229.2.52.232/32229.2.52.232 to 229.2.52.232—1
234229.2.52.233/32229.2.52.233 to 229.2.52.233—1
235229.2.52.234/32229.2.52.234 to 229.2.52.234—1
236229.2.52.235/32229.2.52.235 to 229.2.52.235—1
237229.2.52.236/32229.2.52.236 to 229.2.52.236—1
238229.2.52.237/32229.2.52.237 to 229.2.52.237—1
239229.2.52.238/32229.2.52.238 to 229.2.52.238—1
240229.2.52.239/32229.2.52.239 to 229.2.52.239—1
241229.2.52.240/32229.2.52.240 to 229.2.52.240—1
242229.2.52.241/32229.2.52.241 to 229.2.52.241—1
243229.2.52.242/32229.2.52.242 to 229.2.52.242—1
244229.2.52.243/32229.2.52.243 to 229.2.52.243—1
245229.2.52.244/32229.2.52.244 to 229.2.52.244—1
246229.2.52.245/32229.2.52.245 to 229.2.52.245—1
247229.2.52.246/32229.2.52.246 to 229.2.52.246—1
248229.2.52.247/32229.2.52.247 to 229.2.52.247—1
249229.2.52.248/32229.2.52.248 to 229.2.52.248—1
250229.2.52.249/32229.2.52.249 to 229.2.52.249—1
251229.2.52.250/32229.2.52.250 to 229.2.52.250—1
252229.2.52.251/32229.2.52.251 to 229.2.52.251—1
253229.2.52.252/32229.2.52.252 to 229.2.52.252—1
254229.2.52.253/32229.2.52.253 to 229.2.52.253—1
255229.2.52.254/32229.2.52.254 to 229.2.52.254—1
256229.2.52.255/32229.2.52.255 to 229.2.52.255—1

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.