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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.

Network226.131.40.0/22
Usable hosts1,022
Subnet mask255.255.252.0
Addresses1,024
Network address
226.131.40.0
Broadcast address
226.131.43.255
First usable
226.131.40.1
Last usable
226.131.43.254
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 E2832800 · Integer 3800246272 to 3800247295
Reverse DNS zones
40.131.226.in-addr.arpa
41.131.226.in-addr.arpa
42.131.226.in-addr.arpa
43.131.226.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
Address11100010.10000011.00101000.00000000226.131.40.0
Subnet mask11111111.11111111.11111100.00000000255.255.252.0
Network11100010.10000011.00101000.00000000226.131.40.0
Broadcast11100010.10000011.00101011.11111111226.131.43.255
Split into smaller subnets/30
/23 (2)/24 (4)/25 (8)/26 (16)/27 (32)/28 (64)/29 (128)/30 (256)/31 (512)/32 (1,024)

226.131.40.0/22 makes 256 subnets of /30.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
1226.131.40.0/30226.131.40.1 to 226.131.40.2226.131.40.32
2226.131.40.4/30226.131.40.5 to 226.131.40.6226.131.40.72
3226.131.40.8/30226.131.40.9 to 226.131.40.10226.131.40.112
4226.131.40.12/30226.131.40.13 to 226.131.40.14226.131.40.152
5226.131.40.16/30226.131.40.17 to 226.131.40.18226.131.40.192
6226.131.40.20/30226.131.40.21 to 226.131.40.22226.131.40.232
7226.131.40.24/30226.131.40.25 to 226.131.40.26226.131.40.272
8226.131.40.28/30226.131.40.29 to 226.131.40.30226.131.40.312
9226.131.40.32/30226.131.40.33 to 226.131.40.34226.131.40.352
10226.131.40.36/30226.131.40.37 to 226.131.40.38226.131.40.392
11226.131.40.40/30226.131.40.41 to 226.131.40.42226.131.40.432
12226.131.40.44/30226.131.40.45 to 226.131.40.46226.131.40.472
13226.131.40.48/30226.131.40.49 to 226.131.40.50226.131.40.512
14226.131.40.52/30226.131.40.53 to 226.131.40.54226.131.40.552
15226.131.40.56/30226.131.40.57 to 226.131.40.58226.131.40.592
16226.131.40.60/30226.131.40.61 to 226.131.40.62226.131.40.632
17226.131.40.64/30226.131.40.65 to 226.131.40.66226.131.40.672
18226.131.40.68/30226.131.40.69 to 226.131.40.70226.131.40.712
19226.131.40.72/30226.131.40.73 to 226.131.40.74226.131.40.752
20226.131.40.76/30226.131.40.77 to 226.131.40.78226.131.40.792
21226.131.40.80/30226.131.40.81 to 226.131.40.82226.131.40.832
22226.131.40.84/30226.131.40.85 to 226.131.40.86226.131.40.872
23226.131.40.88/30226.131.40.89 to 226.131.40.90226.131.40.912
24226.131.40.92/30226.131.40.93 to 226.131.40.94226.131.40.952
25226.131.40.96/30226.131.40.97 to 226.131.40.98226.131.40.992
26226.131.40.100/30226.131.40.101 to 226.131.40.102226.131.40.1032
27226.131.40.104/30226.131.40.105 to 226.131.40.106226.131.40.1072
28226.131.40.108/30226.131.40.109 to 226.131.40.110226.131.40.1112
29226.131.40.112/30226.131.40.113 to 226.131.40.114226.131.40.1152
30226.131.40.116/30226.131.40.117 to 226.131.40.118226.131.40.1192
31226.131.40.120/30226.131.40.121 to 226.131.40.122226.131.40.1232
32226.131.40.124/30226.131.40.125 to 226.131.40.126226.131.40.1272
33226.131.40.128/30226.131.40.129 to 226.131.40.130226.131.40.1312
34226.131.40.132/30226.131.40.133 to 226.131.40.134226.131.40.1352
35226.131.40.136/30226.131.40.137 to 226.131.40.138226.131.40.1392
36226.131.40.140/30226.131.40.141 to 226.131.40.142226.131.40.1432
37226.131.40.144/30226.131.40.145 to 226.131.40.146226.131.40.1472
38226.131.40.148/30226.131.40.149 to 226.131.40.150226.131.40.1512
39226.131.40.152/30226.131.40.153 to 226.131.40.154226.131.40.1552
40226.131.40.156/30226.131.40.157 to 226.131.40.158226.131.40.1592
41226.131.40.160/30226.131.40.161 to 226.131.40.162226.131.40.1632
42226.131.40.164/30226.131.40.165 to 226.131.40.166226.131.40.1672
43226.131.40.168/30226.131.40.169 to 226.131.40.170226.131.40.1712
44226.131.40.172/30226.131.40.173 to 226.131.40.174226.131.40.1752
45226.131.40.176/30226.131.40.177 to 226.131.40.178226.131.40.1792
46226.131.40.180/30226.131.40.181 to 226.131.40.182226.131.40.1832
47226.131.40.184/30226.131.40.185 to 226.131.40.186226.131.40.1872
48226.131.40.188/30226.131.40.189 to 226.131.40.190226.131.40.1912
49226.131.40.192/30226.131.40.193 to 226.131.40.194226.131.40.1952
50226.131.40.196/30226.131.40.197 to 226.131.40.198226.131.40.1992
51226.131.40.200/30226.131.40.201 to 226.131.40.202226.131.40.2032
52226.131.40.204/30226.131.40.205 to 226.131.40.206226.131.40.2072
53226.131.40.208/30226.131.40.209 to 226.131.40.210226.131.40.2112
54226.131.40.212/30226.131.40.213 to 226.131.40.214226.131.40.2152
55226.131.40.216/30226.131.40.217 to 226.131.40.218226.131.40.2192
56226.131.40.220/30226.131.40.221 to 226.131.40.222226.131.40.2232
57226.131.40.224/30226.131.40.225 to 226.131.40.226226.131.40.2272
58226.131.40.228/30226.131.40.229 to 226.131.40.230226.131.40.2312
59226.131.40.232/30226.131.40.233 to 226.131.40.234226.131.40.2352
60226.131.40.236/30226.131.40.237 to 226.131.40.238226.131.40.2392
61226.131.40.240/30226.131.40.241 to 226.131.40.242226.131.40.2432
62226.131.40.244/30226.131.40.245 to 226.131.40.246226.131.40.2472
63226.131.40.248/30226.131.40.249 to 226.131.40.250226.131.40.2512
64226.131.40.252/30226.131.40.253 to 226.131.40.254226.131.40.2552
65226.131.41.0/30226.131.41.1 to 226.131.41.2226.131.41.32
66226.131.41.4/30226.131.41.5 to 226.131.41.6226.131.41.72
67226.131.41.8/30226.131.41.9 to 226.131.41.10226.131.41.112
68226.131.41.12/30226.131.41.13 to 226.131.41.14226.131.41.152
69226.131.41.16/30226.131.41.17 to 226.131.41.18226.131.41.192
70226.131.41.20/30226.131.41.21 to 226.131.41.22226.131.41.232
71226.131.41.24/30226.131.41.25 to 226.131.41.26226.131.41.272
72226.131.41.28/30226.131.41.29 to 226.131.41.30226.131.41.312
73226.131.41.32/30226.131.41.33 to 226.131.41.34226.131.41.352
74226.131.41.36/30226.131.41.37 to 226.131.41.38226.131.41.392
75226.131.41.40/30226.131.41.41 to 226.131.41.42226.131.41.432
76226.131.41.44/30226.131.41.45 to 226.131.41.46226.131.41.472
77226.131.41.48/30226.131.41.49 to 226.131.41.50226.131.41.512
78226.131.41.52/30226.131.41.53 to 226.131.41.54226.131.41.552
79226.131.41.56/30226.131.41.57 to 226.131.41.58226.131.41.592
80226.131.41.60/30226.131.41.61 to 226.131.41.62226.131.41.632
81226.131.41.64/30226.131.41.65 to 226.131.41.66226.131.41.672
82226.131.41.68/30226.131.41.69 to 226.131.41.70226.131.41.712
83226.131.41.72/30226.131.41.73 to 226.131.41.74226.131.41.752
84226.131.41.76/30226.131.41.77 to 226.131.41.78226.131.41.792
85226.131.41.80/30226.131.41.81 to 226.131.41.82226.131.41.832
86226.131.41.84/30226.131.41.85 to 226.131.41.86226.131.41.872
87226.131.41.88/30226.131.41.89 to 226.131.41.90226.131.41.912
88226.131.41.92/30226.131.41.93 to 226.131.41.94226.131.41.952
89226.131.41.96/30226.131.41.97 to 226.131.41.98226.131.41.992
90226.131.41.100/30226.131.41.101 to 226.131.41.102226.131.41.1032
91226.131.41.104/30226.131.41.105 to 226.131.41.106226.131.41.1072
92226.131.41.108/30226.131.41.109 to 226.131.41.110226.131.41.1112
93226.131.41.112/30226.131.41.113 to 226.131.41.114226.131.41.1152
94226.131.41.116/30226.131.41.117 to 226.131.41.118226.131.41.1192
95226.131.41.120/30226.131.41.121 to 226.131.41.122226.131.41.1232
96226.131.41.124/30226.131.41.125 to 226.131.41.126226.131.41.1272
97226.131.41.128/30226.131.41.129 to 226.131.41.130226.131.41.1312
98226.131.41.132/30226.131.41.133 to 226.131.41.134226.131.41.1352
99226.131.41.136/30226.131.41.137 to 226.131.41.138226.131.41.1392
100226.131.41.140/30226.131.41.141 to 226.131.41.142226.131.41.1432
101226.131.41.144/30226.131.41.145 to 226.131.41.146226.131.41.1472
102226.131.41.148/30226.131.41.149 to 226.131.41.150226.131.41.1512
103226.131.41.152/30226.131.41.153 to 226.131.41.154226.131.41.1552
104226.131.41.156/30226.131.41.157 to 226.131.41.158226.131.41.1592
105226.131.41.160/30226.131.41.161 to 226.131.41.162226.131.41.1632
106226.131.41.164/30226.131.41.165 to 226.131.41.166226.131.41.1672
107226.131.41.168/30226.131.41.169 to 226.131.41.170226.131.41.1712
108226.131.41.172/30226.131.41.173 to 226.131.41.174226.131.41.1752
109226.131.41.176/30226.131.41.177 to 226.131.41.178226.131.41.1792
110226.131.41.180/30226.131.41.181 to 226.131.41.182226.131.41.1832
111226.131.41.184/30226.131.41.185 to 226.131.41.186226.131.41.1872
112226.131.41.188/30226.131.41.189 to 226.131.41.190226.131.41.1912
113226.131.41.192/30226.131.41.193 to 226.131.41.194226.131.41.1952
114226.131.41.196/30226.131.41.197 to 226.131.41.198226.131.41.1992
115226.131.41.200/30226.131.41.201 to 226.131.41.202226.131.41.2032
116226.131.41.204/30226.131.41.205 to 226.131.41.206226.131.41.2072
117226.131.41.208/30226.131.41.209 to 226.131.41.210226.131.41.2112
118226.131.41.212/30226.131.41.213 to 226.131.41.214226.131.41.2152
119226.131.41.216/30226.131.41.217 to 226.131.41.218226.131.41.2192
120226.131.41.220/30226.131.41.221 to 226.131.41.222226.131.41.2232
121226.131.41.224/30226.131.41.225 to 226.131.41.226226.131.41.2272
122226.131.41.228/30226.131.41.229 to 226.131.41.230226.131.41.2312
123226.131.41.232/30226.131.41.233 to 226.131.41.234226.131.41.2352
124226.131.41.236/30226.131.41.237 to 226.131.41.238226.131.41.2392
125226.131.41.240/30226.131.41.241 to 226.131.41.242226.131.41.2432
126226.131.41.244/30226.131.41.245 to 226.131.41.246226.131.41.2472
127226.131.41.248/30226.131.41.249 to 226.131.41.250226.131.41.2512
128226.131.41.252/30226.131.41.253 to 226.131.41.254226.131.41.2552
129226.131.42.0/30226.131.42.1 to 226.131.42.2226.131.42.32
130226.131.42.4/30226.131.42.5 to 226.131.42.6226.131.42.72
131226.131.42.8/30226.131.42.9 to 226.131.42.10226.131.42.112
132226.131.42.12/30226.131.42.13 to 226.131.42.14226.131.42.152
133226.131.42.16/30226.131.42.17 to 226.131.42.18226.131.42.192
134226.131.42.20/30226.131.42.21 to 226.131.42.22226.131.42.232
135226.131.42.24/30226.131.42.25 to 226.131.42.26226.131.42.272
136226.131.42.28/30226.131.42.29 to 226.131.42.30226.131.42.312
137226.131.42.32/30226.131.42.33 to 226.131.42.34226.131.42.352
138226.131.42.36/30226.131.42.37 to 226.131.42.38226.131.42.392
139226.131.42.40/30226.131.42.41 to 226.131.42.42226.131.42.432
140226.131.42.44/30226.131.42.45 to 226.131.42.46226.131.42.472
141226.131.42.48/30226.131.42.49 to 226.131.42.50226.131.42.512
142226.131.42.52/30226.131.42.53 to 226.131.42.54226.131.42.552
143226.131.42.56/30226.131.42.57 to 226.131.42.58226.131.42.592
144226.131.42.60/30226.131.42.61 to 226.131.42.62226.131.42.632
145226.131.42.64/30226.131.42.65 to 226.131.42.66226.131.42.672
146226.131.42.68/30226.131.42.69 to 226.131.42.70226.131.42.712
147226.131.42.72/30226.131.42.73 to 226.131.42.74226.131.42.752
148226.131.42.76/30226.131.42.77 to 226.131.42.78226.131.42.792
149226.131.42.80/30226.131.42.81 to 226.131.42.82226.131.42.832
150226.131.42.84/30226.131.42.85 to 226.131.42.86226.131.42.872
151226.131.42.88/30226.131.42.89 to 226.131.42.90226.131.42.912
152226.131.42.92/30226.131.42.93 to 226.131.42.94226.131.42.952
153226.131.42.96/30226.131.42.97 to 226.131.42.98226.131.42.992
154226.131.42.100/30226.131.42.101 to 226.131.42.102226.131.42.1032
155226.131.42.104/30226.131.42.105 to 226.131.42.106226.131.42.1072
156226.131.42.108/30226.131.42.109 to 226.131.42.110226.131.42.1112
157226.131.42.112/30226.131.42.113 to 226.131.42.114226.131.42.1152
158226.131.42.116/30226.131.42.117 to 226.131.42.118226.131.42.1192
159226.131.42.120/30226.131.42.121 to 226.131.42.122226.131.42.1232
160226.131.42.124/30226.131.42.125 to 226.131.42.126226.131.42.1272
161226.131.42.128/30226.131.42.129 to 226.131.42.130226.131.42.1312
162226.131.42.132/30226.131.42.133 to 226.131.42.134226.131.42.1352
163226.131.42.136/30226.131.42.137 to 226.131.42.138226.131.42.1392
164226.131.42.140/30226.131.42.141 to 226.131.42.142226.131.42.1432
165226.131.42.144/30226.131.42.145 to 226.131.42.146226.131.42.1472
166226.131.42.148/30226.131.42.149 to 226.131.42.150226.131.42.1512
167226.131.42.152/30226.131.42.153 to 226.131.42.154226.131.42.1552
168226.131.42.156/30226.131.42.157 to 226.131.42.158226.131.42.1592
169226.131.42.160/30226.131.42.161 to 226.131.42.162226.131.42.1632
170226.131.42.164/30226.131.42.165 to 226.131.42.166226.131.42.1672
171226.131.42.168/30226.131.42.169 to 226.131.42.170226.131.42.1712
172226.131.42.172/30226.131.42.173 to 226.131.42.174226.131.42.1752
173226.131.42.176/30226.131.42.177 to 226.131.42.178226.131.42.1792
174226.131.42.180/30226.131.42.181 to 226.131.42.182226.131.42.1832
175226.131.42.184/30226.131.42.185 to 226.131.42.186226.131.42.1872
176226.131.42.188/30226.131.42.189 to 226.131.42.190226.131.42.1912
177226.131.42.192/30226.131.42.193 to 226.131.42.194226.131.42.1952
178226.131.42.196/30226.131.42.197 to 226.131.42.198226.131.42.1992
179226.131.42.200/30226.131.42.201 to 226.131.42.202226.131.42.2032
180226.131.42.204/30226.131.42.205 to 226.131.42.206226.131.42.2072
181226.131.42.208/30226.131.42.209 to 226.131.42.210226.131.42.2112
182226.131.42.212/30226.131.42.213 to 226.131.42.214226.131.42.2152
183226.131.42.216/30226.131.42.217 to 226.131.42.218226.131.42.2192
184226.131.42.220/30226.131.42.221 to 226.131.42.222226.131.42.2232
185226.131.42.224/30226.131.42.225 to 226.131.42.226226.131.42.2272
186226.131.42.228/30226.131.42.229 to 226.131.42.230226.131.42.2312
187226.131.42.232/30226.131.42.233 to 226.131.42.234226.131.42.2352
188226.131.42.236/30226.131.42.237 to 226.131.42.238226.131.42.2392
189226.131.42.240/30226.131.42.241 to 226.131.42.242226.131.42.2432
190226.131.42.244/30226.131.42.245 to 226.131.42.246226.131.42.2472
191226.131.42.248/30226.131.42.249 to 226.131.42.250226.131.42.2512
192226.131.42.252/30226.131.42.253 to 226.131.42.254226.131.42.2552
193226.131.43.0/30226.131.43.1 to 226.131.43.2226.131.43.32
194226.131.43.4/30226.131.43.5 to 226.131.43.6226.131.43.72
195226.131.43.8/30226.131.43.9 to 226.131.43.10226.131.43.112
196226.131.43.12/30226.131.43.13 to 226.131.43.14226.131.43.152
197226.131.43.16/30226.131.43.17 to 226.131.43.18226.131.43.192
198226.131.43.20/30226.131.43.21 to 226.131.43.22226.131.43.232
199226.131.43.24/30226.131.43.25 to 226.131.43.26226.131.43.272
200226.131.43.28/30226.131.43.29 to 226.131.43.30226.131.43.312
201226.131.43.32/30226.131.43.33 to 226.131.43.34226.131.43.352
202226.131.43.36/30226.131.43.37 to 226.131.43.38226.131.43.392
203226.131.43.40/30226.131.43.41 to 226.131.43.42226.131.43.432
204226.131.43.44/30226.131.43.45 to 226.131.43.46226.131.43.472
205226.131.43.48/30226.131.43.49 to 226.131.43.50226.131.43.512
206226.131.43.52/30226.131.43.53 to 226.131.43.54226.131.43.552
207226.131.43.56/30226.131.43.57 to 226.131.43.58226.131.43.592
208226.131.43.60/30226.131.43.61 to 226.131.43.62226.131.43.632
209226.131.43.64/30226.131.43.65 to 226.131.43.66226.131.43.672
210226.131.43.68/30226.131.43.69 to 226.131.43.70226.131.43.712
211226.131.43.72/30226.131.43.73 to 226.131.43.74226.131.43.752
212226.131.43.76/30226.131.43.77 to 226.131.43.78226.131.43.792
213226.131.43.80/30226.131.43.81 to 226.131.43.82226.131.43.832
214226.131.43.84/30226.131.43.85 to 226.131.43.86226.131.43.872
215226.131.43.88/30226.131.43.89 to 226.131.43.90226.131.43.912
216226.131.43.92/30226.131.43.93 to 226.131.43.94226.131.43.952
217226.131.43.96/30226.131.43.97 to 226.131.43.98226.131.43.992
218226.131.43.100/30226.131.43.101 to 226.131.43.102226.131.43.1032
219226.131.43.104/30226.131.43.105 to 226.131.43.106226.131.43.1072
220226.131.43.108/30226.131.43.109 to 226.131.43.110226.131.43.1112
221226.131.43.112/30226.131.43.113 to 226.131.43.114226.131.43.1152
222226.131.43.116/30226.131.43.117 to 226.131.43.118226.131.43.1192
223226.131.43.120/30226.131.43.121 to 226.131.43.122226.131.43.1232
224226.131.43.124/30226.131.43.125 to 226.131.43.126226.131.43.1272
225226.131.43.128/30226.131.43.129 to 226.131.43.130226.131.43.1312
226226.131.43.132/30226.131.43.133 to 226.131.43.134226.131.43.1352
227226.131.43.136/30226.131.43.137 to 226.131.43.138226.131.43.1392
228226.131.43.140/30226.131.43.141 to 226.131.43.142226.131.43.1432
229226.131.43.144/30226.131.43.145 to 226.131.43.146226.131.43.1472
230226.131.43.148/30226.131.43.149 to 226.131.43.150226.131.43.1512
231226.131.43.152/30226.131.43.153 to 226.131.43.154226.131.43.1552
232226.131.43.156/30226.131.43.157 to 226.131.43.158226.131.43.1592
233226.131.43.160/30226.131.43.161 to 226.131.43.162226.131.43.1632
234226.131.43.164/30226.131.43.165 to 226.131.43.166226.131.43.1672
235226.131.43.168/30226.131.43.169 to 226.131.43.170226.131.43.1712
236226.131.43.172/30226.131.43.173 to 226.131.43.174226.131.43.1752
237226.131.43.176/30226.131.43.177 to 226.131.43.178226.131.43.1792
238226.131.43.180/30226.131.43.181 to 226.131.43.182226.131.43.1832
239226.131.43.184/30226.131.43.185 to 226.131.43.186226.131.43.1872
240226.131.43.188/30226.131.43.189 to 226.131.43.190226.131.43.1912
241226.131.43.192/30226.131.43.193 to 226.131.43.194226.131.43.1952
242226.131.43.196/30226.131.43.197 to 226.131.43.198226.131.43.1992
243226.131.43.200/30226.131.43.201 to 226.131.43.202226.131.43.2032
244226.131.43.204/30226.131.43.205 to 226.131.43.206226.131.43.2072
245226.131.43.208/30226.131.43.209 to 226.131.43.210226.131.43.2112
246226.131.43.212/30226.131.43.213 to 226.131.43.214226.131.43.2152
247226.131.43.216/30226.131.43.217 to 226.131.43.218226.131.43.2192
248226.131.43.220/30226.131.43.221 to 226.131.43.222226.131.43.2232
249226.131.43.224/30226.131.43.225 to 226.131.43.226226.131.43.2272
250226.131.43.228/30226.131.43.229 to 226.131.43.230226.131.43.2312
251226.131.43.232/30226.131.43.233 to 226.131.43.234226.131.43.2352
252226.131.43.236/30226.131.43.237 to 226.131.43.238226.131.43.2392
253226.131.43.240/30226.131.43.241 to 226.131.43.242226.131.43.2432
254226.131.43.244/30226.131.43.245 to 226.131.43.246226.131.43.2472
255226.131.43.248/30226.131.43.249 to 226.131.43.250226.131.43.2512
256226.131.43.252/30226.131.43.253 to 226.131.43.254226.131.43.2552

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.