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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.

Network230.2.4.0/22
Usable hosts1,022
Subnet mask255.255.252.0
Addresses1,024
Network address
230.2.4.0
Broadcast address
230.2.7.255
First usable
230.2.4.1
Last usable
230.2.7.254
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 E6020400 · Integer 3858891776 to 3858892799
Reverse DNS zones
4.2.230.in-addr.arpa
5.2.230.in-addr.arpa
6.2.230.in-addr.arpa
7.2.230.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
Address11100110.00000010.00000100.00000000230.2.4.0
Subnet mask11111111.11111111.11111100.00000000255.255.252.0
Network11100110.00000010.00000100.00000000230.2.4.0
Broadcast11100110.00000010.00000111.11111111230.2.7.255
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)

230.2.4.0/22 makes 256 subnets of /30.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
1230.2.4.0/30230.2.4.1 to 230.2.4.2230.2.4.32
2230.2.4.4/30230.2.4.5 to 230.2.4.6230.2.4.72
3230.2.4.8/30230.2.4.9 to 230.2.4.10230.2.4.112
4230.2.4.12/30230.2.4.13 to 230.2.4.14230.2.4.152
5230.2.4.16/30230.2.4.17 to 230.2.4.18230.2.4.192
6230.2.4.20/30230.2.4.21 to 230.2.4.22230.2.4.232
7230.2.4.24/30230.2.4.25 to 230.2.4.26230.2.4.272
8230.2.4.28/30230.2.4.29 to 230.2.4.30230.2.4.312
9230.2.4.32/30230.2.4.33 to 230.2.4.34230.2.4.352
10230.2.4.36/30230.2.4.37 to 230.2.4.38230.2.4.392
11230.2.4.40/30230.2.4.41 to 230.2.4.42230.2.4.432
12230.2.4.44/30230.2.4.45 to 230.2.4.46230.2.4.472
13230.2.4.48/30230.2.4.49 to 230.2.4.50230.2.4.512
14230.2.4.52/30230.2.4.53 to 230.2.4.54230.2.4.552
15230.2.4.56/30230.2.4.57 to 230.2.4.58230.2.4.592
16230.2.4.60/30230.2.4.61 to 230.2.4.62230.2.4.632
17230.2.4.64/30230.2.4.65 to 230.2.4.66230.2.4.672
18230.2.4.68/30230.2.4.69 to 230.2.4.70230.2.4.712
19230.2.4.72/30230.2.4.73 to 230.2.4.74230.2.4.752
20230.2.4.76/30230.2.4.77 to 230.2.4.78230.2.4.792
21230.2.4.80/30230.2.4.81 to 230.2.4.82230.2.4.832
22230.2.4.84/30230.2.4.85 to 230.2.4.86230.2.4.872
23230.2.4.88/30230.2.4.89 to 230.2.4.90230.2.4.912
24230.2.4.92/30230.2.4.93 to 230.2.4.94230.2.4.952
25230.2.4.96/30230.2.4.97 to 230.2.4.98230.2.4.992
26230.2.4.100/30230.2.4.101 to 230.2.4.102230.2.4.1032
27230.2.4.104/30230.2.4.105 to 230.2.4.106230.2.4.1072
28230.2.4.108/30230.2.4.109 to 230.2.4.110230.2.4.1112
29230.2.4.112/30230.2.4.113 to 230.2.4.114230.2.4.1152
30230.2.4.116/30230.2.4.117 to 230.2.4.118230.2.4.1192
31230.2.4.120/30230.2.4.121 to 230.2.4.122230.2.4.1232
32230.2.4.124/30230.2.4.125 to 230.2.4.126230.2.4.1272
33230.2.4.128/30230.2.4.129 to 230.2.4.130230.2.4.1312
34230.2.4.132/30230.2.4.133 to 230.2.4.134230.2.4.1352
35230.2.4.136/30230.2.4.137 to 230.2.4.138230.2.4.1392
36230.2.4.140/30230.2.4.141 to 230.2.4.142230.2.4.1432
37230.2.4.144/30230.2.4.145 to 230.2.4.146230.2.4.1472
38230.2.4.148/30230.2.4.149 to 230.2.4.150230.2.4.1512
39230.2.4.152/30230.2.4.153 to 230.2.4.154230.2.4.1552
40230.2.4.156/30230.2.4.157 to 230.2.4.158230.2.4.1592
41230.2.4.160/30230.2.4.161 to 230.2.4.162230.2.4.1632
42230.2.4.164/30230.2.4.165 to 230.2.4.166230.2.4.1672
43230.2.4.168/30230.2.4.169 to 230.2.4.170230.2.4.1712
44230.2.4.172/30230.2.4.173 to 230.2.4.174230.2.4.1752
45230.2.4.176/30230.2.4.177 to 230.2.4.178230.2.4.1792
46230.2.4.180/30230.2.4.181 to 230.2.4.182230.2.4.1832
47230.2.4.184/30230.2.4.185 to 230.2.4.186230.2.4.1872
48230.2.4.188/30230.2.4.189 to 230.2.4.190230.2.4.1912
49230.2.4.192/30230.2.4.193 to 230.2.4.194230.2.4.1952
50230.2.4.196/30230.2.4.197 to 230.2.4.198230.2.4.1992
51230.2.4.200/30230.2.4.201 to 230.2.4.202230.2.4.2032
52230.2.4.204/30230.2.4.205 to 230.2.4.206230.2.4.2072
53230.2.4.208/30230.2.4.209 to 230.2.4.210230.2.4.2112
54230.2.4.212/30230.2.4.213 to 230.2.4.214230.2.4.2152
55230.2.4.216/30230.2.4.217 to 230.2.4.218230.2.4.2192
56230.2.4.220/30230.2.4.221 to 230.2.4.222230.2.4.2232
57230.2.4.224/30230.2.4.225 to 230.2.4.226230.2.4.2272
58230.2.4.228/30230.2.4.229 to 230.2.4.230230.2.4.2312
59230.2.4.232/30230.2.4.233 to 230.2.4.234230.2.4.2352
60230.2.4.236/30230.2.4.237 to 230.2.4.238230.2.4.2392
61230.2.4.240/30230.2.4.241 to 230.2.4.242230.2.4.2432
62230.2.4.244/30230.2.4.245 to 230.2.4.246230.2.4.2472
63230.2.4.248/30230.2.4.249 to 230.2.4.250230.2.4.2512
64230.2.4.252/30230.2.4.253 to 230.2.4.254230.2.4.2552
65230.2.5.0/30230.2.5.1 to 230.2.5.2230.2.5.32
66230.2.5.4/30230.2.5.5 to 230.2.5.6230.2.5.72
67230.2.5.8/30230.2.5.9 to 230.2.5.10230.2.5.112
68230.2.5.12/30230.2.5.13 to 230.2.5.14230.2.5.152
69230.2.5.16/30230.2.5.17 to 230.2.5.18230.2.5.192
70230.2.5.20/30230.2.5.21 to 230.2.5.22230.2.5.232
71230.2.5.24/30230.2.5.25 to 230.2.5.26230.2.5.272
72230.2.5.28/30230.2.5.29 to 230.2.5.30230.2.5.312
73230.2.5.32/30230.2.5.33 to 230.2.5.34230.2.5.352
74230.2.5.36/30230.2.5.37 to 230.2.5.38230.2.5.392
75230.2.5.40/30230.2.5.41 to 230.2.5.42230.2.5.432
76230.2.5.44/30230.2.5.45 to 230.2.5.46230.2.5.472
77230.2.5.48/30230.2.5.49 to 230.2.5.50230.2.5.512
78230.2.5.52/30230.2.5.53 to 230.2.5.54230.2.5.552
79230.2.5.56/30230.2.5.57 to 230.2.5.58230.2.5.592
80230.2.5.60/30230.2.5.61 to 230.2.5.62230.2.5.632
81230.2.5.64/30230.2.5.65 to 230.2.5.66230.2.5.672
82230.2.5.68/30230.2.5.69 to 230.2.5.70230.2.5.712
83230.2.5.72/30230.2.5.73 to 230.2.5.74230.2.5.752
84230.2.5.76/30230.2.5.77 to 230.2.5.78230.2.5.792
85230.2.5.80/30230.2.5.81 to 230.2.5.82230.2.5.832
86230.2.5.84/30230.2.5.85 to 230.2.5.86230.2.5.872
87230.2.5.88/30230.2.5.89 to 230.2.5.90230.2.5.912
88230.2.5.92/30230.2.5.93 to 230.2.5.94230.2.5.952
89230.2.5.96/30230.2.5.97 to 230.2.5.98230.2.5.992
90230.2.5.100/30230.2.5.101 to 230.2.5.102230.2.5.1032
91230.2.5.104/30230.2.5.105 to 230.2.5.106230.2.5.1072
92230.2.5.108/30230.2.5.109 to 230.2.5.110230.2.5.1112
93230.2.5.112/30230.2.5.113 to 230.2.5.114230.2.5.1152
94230.2.5.116/30230.2.5.117 to 230.2.5.118230.2.5.1192
95230.2.5.120/30230.2.5.121 to 230.2.5.122230.2.5.1232
96230.2.5.124/30230.2.5.125 to 230.2.5.126230.2.5.1272
97230.2.5.128/30230.2.5.129 to 230.2.5.130230.2.5.1312
98230.2.5.132/30230.2.5.133 to 230.2.5.134230.2.5.1352
99230.2.5.136/30230.2.5.137 to 230.2.5.138230.2.5.1392
100230.2.5.140/30230.2.5.141 to 230.2.5.142230.2.5.1432
101230.2.5.144/30230.2.5.145 to 230.2.5.146230.2.5.1472
102230.2.5.148/30230.2.5.149 to 230.2.5.150230.2.5.1512
103230.2.5.152/30230.2.5.153 to 230.2.5.154230.2.5.1552
104230.2.5.156/30230.2.5.157 to 230.2.5.158230.2.5.1592
105230.2.5.160/30230.2.5.161 to 230.2.5.162230.2.5.1632
106230.2.5.164/30230.2.5.165 to 230.2.5.166230.2.5.1672
107230.2.5.168/30230.2.5.169 to 230.2.5.170230.2.5.1712
108230.2.5.172/30230.2.5.173 to 230.2.5.174230.2.5.1752
109230.2.5.176/30230.2.5.177 to 230.2.5.178230.2.5.1792
110230.2.5.180/30230.2.5.181 to 230.2.5.182230.2.5.1832
111230.2.5.184/30230.2.5.185 to 230.2.5.186230.2.5.1872
112230.2.5.188/30230.2.5.189 to 230.2.5.190230.2.5.1912
113230.2.5.192/30230.2.5.193 to 230.2.5.194230.2.5.1952
114230.2.5.196/30230.2.5.197 to 230.2.5.198230.2.5.1992
115230.2.5.200/30230.2.5.201 to 230.2.5.202230.2.5.2032
116230.2.5.204/30230.2.5.205 to 230.2.5.206230.2.5.2072
117230.2.5.208/30230.2.5.209 to 230.2.5.210230.2.5.2112
118230.2.5.212/30230.2.5.213 to 230.2.5.214230.2.5.2152
119230.2.5.216/30230.2.5.217 to 230.2.5.218230.2.5.2192
120230.2.5.220/30230.2.5.221 to 230.2.5.222230.2.5.2232
121230.2.5.224/30230.2.5.225 to 230.2.5.226230.2.5.2272
122230.2.5.228/30230.2.5.229 to 230.2.5.230230.2.5.2312
123230.2.5.232/30230.2.5.233 to 230.2.5.234230.2.5.2352
124230.2.5.236/30230.2.5.237 to 230.2.5.238230.2.5.2392
125230.2.5.240/30230.2.5.241 to 230.2.5.242230.2.5.2432
126230.2.5.244/30230.2.5.245 to 230.2.5.246230.2.5.2472
127230.2.5.248/30230.2.5.249 to 230.2.5.250230.2.5.2512
128230.2.5.252/30230.2.5.253 to 230.2.5.254230.2.5.2552
129230.2.6.0/30230.2.6.1 to 230.2.6.2230.2.6.32
130230.2.6.4/30230.2.6.5 to 230.2.6.6230.2.6.72
131230.2.6.8/30230.2.6.9 to 230.2.6.10230.2.6.112
132230.2.6.12/30230.2.6.13 to 230.2.6.14230.2.6.152
133230.2.6.16/30230.2.6.17 to 230.2.6.18230.2.6.192
134230.2.6.20/30230.2.6.21 to 230.2.6.22230.2.6.232
135230.2.6.24/30230.2.6.25 to 230.2.6.26230.2.6.272
136230.2.6.28/30230.2.6.29 to 230.2.6.30230.2.6.312
137230.2.6.32/30230.2.6.33 to 230.2.6.34230.2.6.352
138230.2.6.36/30230.2.6.37 to 230.2.6.38230.2.6.392
139230.2.6.40/30230.2.6.41 to 230.2.6.42230.2.6.432
140230.2.6.44/30230.2.6.45 to 230.2.6.46230.2.6.472
141230.2.6.48/30230.2.6.49 to 230.2.6.50230.2.6.512
142230.2.6.52/30230.2.6.53 to 230.2.6.54230.2.6.552
143230.2.6.56/30230.2.6.57 to 230.2.6.58230.2.6.592
144230.2.6.60/30230.2.6.61 to 230.2.6.62230.2.6.632
145230.2.6.64/30230.2.6.65 to 230.2.6.66230.2.6.672
146230.2.6.68/30230.2.6.69 to 230.2.6.70230.2.6.712
147230.2.6.72/30230.2.6.73 to 230.2.6.74230.2.6.752
148230.2.6.76/30230.2.6.77 to 230.2.6.78230.2.6.792
149230.2.6.80/30230.2.6.81 to 230.2.6.82230.2.6.832
150230.2.6.84/30230.2.6.85 to 230.2.6.86230.2.6.872
151230.2.6.88/30230.2.6.89 to 230.2.6.90230.2.6.912
152230.2.6.92/30230.2.6.93 to 230.2.6.94230.2.6.952
153230.2.6.96/30230.2.6.97 to 230.2.6.98230.2.6.992
154230.2.6.100/30230.2.6.101 to 230.2.6.102230.2.6.1032
155230.2.6.104/30230.2.6.105 to 230.2.6.106230.2.6.1072
156230.2.6.108/30230.2.6.109 to 230.2.6.110230.2.6.1112
157230.2.6.112/30230.2.6.113 to 230.2.6.114230.2.6.1152
158230.2.6.116/30230.2.6.117 to 230.2.6.118230.2.6.1192
159230.2.6.120/30230.2.6.121 to 230.2.6.122230.2.6.1232
160230.2.6.124/30230.2.6.125 to 230.2.6.126230.2.6.1272
161230.2.6.128/30230.2.6.129 to 230.2.6.130230.2.6.1312
162230.2.6.132/30230.2.6.133 to 230.2.6.134230.2.6.1352
163230.2.6.136/30230.2.6.137 to 230.2.6.138230.2.6.1392
164230.2.6.140/30230.2.6.141 to 230.2.6.142230.2.6.1432
165230.2.6.144/30230.2.6.145 to 230.2.6.146230.2.6.1472
166230.2.6.148/30230.2.6.149 to 230.2.6.150230.2.6.1512
167230.2.6.152/30230.2.6.153 to 230.2.6.154230.2.6.1552
168230.2.6.156/30230.2.6.157 to 230.2.6.158230.2.6.1592
169230.2.6.160/30230.2.6.161 to 230.2.6.162230.2.6.1632
170230.2.6.164/30230.2.6.165 to 230.2.6.166230.2.6.1672
171230.2.6.168/30230.2.6.169 to 230.2.6.170230.2.6.1712
172230.2.6.172/30230.2.6.173 to 230.2.6.174230.2.6.1752
173230.2.6.176/30230.2.6.177 to 230.2.6.178230.2.6.1792
174230.2.6.180/30230.2.6.181 to 230.2.6.182230.2.6.1832
175230.2.6.184/30230.2.6.185 to 230.2.6.186230.2.6.1872
176230.2.6.188/30230.2.6.189 to 230.2.6.190230.2.6.1912
177230.2.6.192/30230.2.6.193 to 230.2.6.194230.2.6.1952
178230.2.6.196/30230.2.6.197 to 230.2.6.198230.2.6.1992
179230.2.6.200/30230.2.6.201 to 230.2.6.202230.2.6.2032
180230.2.6.204/30230.2.6.205 to 230.2.6.206230.2.6.2072
181230.2.6.208/30230.2.6.209 to 230.2.6.210230.2.6.2112
182230.2.6.212/30230.2.6.213 to 230.2.6.214230.2.6.2152
183230.2.6.216/30230.2.6.217 to 230.2.6.218230.2.6.2192
184230.2.6.220/30230.2.6.221 to 230.2.6.222230.2.6.2232
185230.2.6.224/30230.2.6.225 to 230.2.6.226230.2.6.2272
186230.2.6.228/30230.2.6.229 to 230.2.6.230230.2.6.2312
187230.2.6.232/30230.2.6.233 to 230.2.6.234230.2.6.2352
188230.2.6.236/30230.2.6.237 to 230.2.6.238230.2.6.2392
189230.2.6.240/30230.2.6.241 to 230.2.6.242230.2.6.2432
190230.2.6.244/30230.2.6.245 to 230.2.6.246230.2.6.2472
191230.2.6.248/30230.2.6.249 to 230.2.6.250230.2.6.2512
192230.2.6.252/30230.2.6.253 to 230.2.6.254230.2.6.2552
193230.2.7.0/30230.2.7.1 to 230.2.7.2230.2.7.32
194230.2.7.4/30230.2.7.5 to 230.2.7.6230.2.7.72
195230.2.7.8/30230.2.7.9 to 230.2.7.10230.2.7.112
196230.2.7.12/30230.2.7.13 to 230.2.7.14230.2.7.152
197230.2.7.16/30230.2.7.17 to 230.2.7.18230.2.7.192
198230.2.7.20/30230.2.7.21 to 230.2.7.22230.2.7.232
199230.2.7.24/30230.2.7.25 to 230.2.7.26230.2.7.272
200230.2.7.28/30230.2.7.29 to 230.2.7.30230.2.7.312
201230.2.7.32/30230.2.7.33 to 230.2.7.34230.2.7.352
202230.2.7.36/30230.2.7.37 to 230.2.7.38230.2.7.392
203230.2.7.40/30230.2.7.41 to 230.2.7.42230.2.7.432
204230.2.7.44/30230.2.7.45 to 230.2.7.46230.2.7.472
205230.2.7.48/30230.2.7.49 to 230.2.7.50230.2.7.512
206230.2.7.52/30230.2.7.53 to 230.2.7.54230.2.7.552
207230.2.7.56/30230.2.7.57 to 230.2.7.58230.2.7.592
208230.2.7.60/30230.2.7.61 to 230.2.7.62230.2.7.632
209230.2.7.64/30230.2.7.65 to 230.2.7.66230.2.7.672
210230.2.7.68/30230.2.7.69 to 230.2.7.70230.2.7.712
211230.2.7.72/30230.2.7.73 to 230.2.7.74230.2.7.752
212230.2.7.76/30230.2.7.77 to 230.2.7.78230.2.7.792
213230.2.7.80/30230.2.7.81 to 230.2.7.82230.2.7.832
214230.2.7.84/30230.2.7.85 to 230.2.7.86230.2.7.872
215230.2.7.88/30230.2.7.89 to 230.2.7.90230.2.7.912
216230.2.7.92/30230.2.7.93 to 230.2.7.94230.2.7.952
217230.2.7.96/30230.2.7.97 to 230.2.7.98230.2.7.992
218230.2.7.100/30230.2.7.101 to 230.2.7.102230.2.7.1032
219230.2.7.104/30230.2.7.105 to 230.2.7.106230.2.7.1072
220230.2.7.108/30230.2.7.109 to 230.2.7.110230.2.7.1112
221230.2.7.112/30230.2.7.113 to 230.2.7.114230.2.7.1152
222230.2.7.116/30230.2.7.117 to 230.2.7.118230.2.7.1192
223230.2.7.120/30230.2.7.121 to 230.2.7.122230.2.7.1232
224230.2.7.124/30230.2.7.125 to 230.2.7.126230.2.7.1272
225230.2.7.128/30230.2.7.129 to 230.2.7.130230.2.7.1312
226230.2.7.132/30230.2.7.133 to 230.2.7.134230.2.7.1352
227230.2.7.136/30230.2.7.137 to 230.2.7.138230.2.7.1392
228230.2.7.140/30230.2.7.141 to 230.2.7.142230.2.7.1432
229230.2.7.144/30230.2.7.145 to 230.2.7.146230.2.7.1472
230230.2.7.148/30230.2.7.149 to 230.2.7.150230.2.7.1512
231230.2.7.152/30230.2.7.153 to 230.2.7.154230.2.7.1552
232230.2.7.156/30230.2.7.157 to 230.2.7.158230.2.7.1592
233230.2.7.160/30230.2.7.161 to 230.2.7.162230.2.7.1632
234230.2.7.164/30230.2.7.165 to 230.2.7.166230.2.7.1672
235230.2.7.168/30230.2.7.169 to 230.2.7.170230.2.7.1712
236230.2.7.172/30230.2.7.173 to 230.2.7.174230.2.7.1752
237230.2.7.176/30230.2.7.177 to 230.2.7.178230.2.7.1792
238230.2.7.180/30230.2.7.181 to 230.2.7.182230.2.7.1832
239230.2.7.184/30230.2.7.185 to 230.2.7.186230.2.7.1872
240230.2.7.188/30230.2.7.189 to 230.2.7.190230.2.7.1912
241230.2.7.192/30230.2.7.193 to 230.2.7.194230.2.7.1952
242230.2.7.196/30230.2.7.197 to 230.2.7.198230.2.7.1992
243230.2.7.200/30230.2.7.201 to 230.2.7.202230.2.7.2032
244230.2.7.204/30230.2.7.205 to 230.2.7.206230.2.7.2072
245230.2.7.208/30230.2.7.209 to 230.2.7.210230.2.7.2112
246230.2.7.212/30230.2.7.213 to 230.2.7.214230.2.7.2152
247230.2.7.216/30230.2.7.217 to 230.2.7.218230.2.7.2192
248230.2.7.220/30230.2.7.221 to 230.2.7.222230.2.7.2232
249230.2.7.224/30230.2.7.225 to 230.2.7.226230.2.7.2272
250230.2.7.228/30230.2.7.229 to 230.2.7.230230.2.7.2312
251230.2.7.232/30230.2.7.233 to 230.2.7.234230.2.7.2352
252230.2.7.236/30230.2.7.237 to 230.2.7.238230.2.7.2392
253230.2.7.240/30230.2.7.241 to 230.2.7.242230.2.7.2432
254230.2.7.244/30230.2.7.245 to 230.2.7.246230.2.7.2472
255230.2.7.248/30230.2.7.249 to 230.2.7.250230.2.7.2512
256230.2.7.252/30230.2.7.253 to 230.2.7.254230.2.7.2552

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.