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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.

Network198.18.228.0/22
Usable hosts1,022
Subnet mask255.255.252.0
Addresses1,024
Network address
198.18.228.0
Broadcast address
198.18.231.255
First usable
198.18.228.1
Last usable
198.18.231.254
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
Benchmarking 198.18.0.0/15
Network equipment testing (RFC 2544)
Old class
C (default /24)
As numbers
Hex C612E400 · Integer 3323126784 to 3323127807
Reverse DNS zones
228.18.198.in-addr.arpa
229.18.198.in-addr.arpa
230.18.198.in-addr.arpa
231.18.198.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
Address11000110.00010010.11100100.00000000198.18.228.0
Subnet mask11111111.11111111.11111100.00000000255.255.252.0
Network11000110.00010010.11100100.00000000198.18.228.0
Broadcast11000110.00010010.11100111.11111111198.18.231.255
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)

198.18.228.0/22 makes 256 subnets of /30.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
1198.18.228.0/30198.18.228.1 to 198.18.228.2198.18.228.32
2198.18.228.4/30198.18.228.5 to 198.18.228.6198.18.228.72
3198.18.228.8/30198.18.228.9 to 198.18.228.10198.18.228.112
4198.18.228.12/30198.18.228.13 to 198.18.228.14198.18.228.152
5198.18.228.16/30198.18.228.17 to 198.18.228.18198.18.228.192
6198.18.228.20/30198.18.228.21 to 198.18.228.22198.18.228.232
7198.18.228.24/30198.18.228.25 to 198.18.228.26198.18.228.272
8198.18.228.28/30198.18.228.29 to 198.18.228.30198.18.228.312
9198.18.228.32/30198.18.228.33 to 198.18.228.34198.18.228.352
10198.18.228.36/30198.18.228.37 to 198.18.228.38198.18.228.392
11198.18.228.40/30198.18.228.41 to 198.18.228.42198.18.228.432
12198.18.228.44/30198.18.228.45 to 198.18.228.46198.18.228.472
13198.18.228.48/30198.18.228.49 to 198.18.228.50198.18.228.512
14198.18.228.52/30198.18.228.53 to 198.18.228.54198.18.228.552
15198.18.228.56/30198.18.228.57 to 198.18.228.58198.18.228.592
16198.18.228.60/30198.18.228.61 to 198.18.228.62198.18.228.632
17198.18.228.64/30198.18.228.65 to 198.18.228.66198.18.228.672
18198.18.228.68/30198.18.228.69 to 198.18.228.70198.18.228.712
19198.18.228.72/30198.18.228.73 to 198.18.228.74198.18.228.752
20198.18.228.76/30198.18.228.77 to 198.18.228.78198.18.228.792
21198.18.228.80/30198.18.228.81 to 198.18.228.82198.18.228.832
22198.18.228.84/30198.18.228.85 to 198.18.228.86198.18.228.872
23198.18.228.88/30198.18.228.89 to 198.18.228.90198.18.228.912
24198.18.228.92/30198.18.228.93 to 198.18.228.94198.18.228.952
25198.18.228.96/30198.18.228.97 to 198.18.228.98198.18.228.992
26198.18.228.100/30198.18.228.101 to 198.18.228.102198.18.228.1032
27198.18.228.104/30198.18.228.105 to 198.18.228.106198.18.228.1072
28198.18.228.108/30198.18.228.109 to 198.18.228.110198.18.228.1112
29198.18.228.112/30198.18.228.113 to 198.18.228.114198.18.228.1152
30198.18.228.116/30198.18.228.117 to 198.18.228.118198.18.228.1192
31198.18.228.120/30198.18.228.121 to 198.18.228.122198.18.228.1232
32198.18.228.124/30198.18.228.125 to 198.18.228.126198.18.228.1272
33198.18.228.128/30198.18.228.129 to 198.18.228.130198.18.228.1312
34198.18.228.132/30198.18.228.133 to 198.18.228.134198.18.228.1352
35198.18.228.136/30198.18.228.137 to 198.18.228.138198.18.228.1392
36198.18.228.140/30198.18.228.141 to 198.18.228.142198.18.228.1432
37198.18.228.144/30198.18.228.145 to 198.18.228.146198.18.228.1472
38198.18.228.148/30198.18.228.149 to 198.18.228.150198.18.228.1512
39198.18.228.152/30198.18.228.153 to 198.18.228.154198.18.228.1552
40198.18.228.156/30198.18.228.157 to 198.18.228.158198.18.228.1592
41198.18.228.160/30198.18.228.161 to 198.18.228.162198.18.228.1632
42198.18.228.164/30198.18.228.165 to 198.18.228.166198.18.228.1672
43198.18.228.168/30198.18.228.169 to 198.18.228.170198.18.228.1712
44198.18.228.172/30198.18.228.173 to 198.18.228.174198.18.228.1752
45198.18.228.176/30198.18.228.177 to 198.18.228.178198.18.228.1792
46198.18.228.180/30198.18.228.181 to 198.18.228.182198.18.228.1832
47198.18.228.184/30198.18.228.185 to 198.18.228.186198.18.228.1872
48198.18.228.188/30198.18.228.189 to 198.18.228.190198.18.228.1912
49198.18.228.192/30198.18.228.193 to 198.18.228.194198.18.228.1952
50198.18.228.196/30198.18.228.197 to 198.18.228.198198.18.228.1992
51198.18.228.200/30198.18.228.201 to 198.18.228.202198.18.228.2032
52198.18.228.204/30198.18.228.205 to 198.18.228.206198.18.228.2072
53198.18.228.208/30198.18.228.209 to 198.18.228.210198.18.228.2112
54198.18.228.212/30198.18.228.213 to 198.18.228.214198.18.228.2152
55198.18.228.216/30198.18.228.217 to 198.18.228.218198.18.228.2192
56198.18.228.220/30198.18.228.221 to 198.18.228.222198.18.228.2232
57198.18.228.224/30198.18.228.225 to 198.18.228.226198.18.228.2272
58198.18.228.228/30198.18.228.229 to 198.18.228.230198.18.228.2312
59198.18.228.232/30198.18.228.233 to 198.18.228.234198.18.228.2352
60198.18.228.236/30198.18.228.237 to 198.18.228.238198.18.228.2392
61198.18.228.240/30198.18.228.241 to 198.18.228.242198.18.228.2432
62198.18.228.244/30198.18.228.245 to 198.18.228.246198.18.228.2472
63198.18.228.248/30198.18.228.249 to 198.18.228.250198.18.228.2512
64198.18.228.252/30198.18.228.253 to 198.18.228.254198.18.228.2552
65198.18.229.0/30198.18.229.1 to 198.18.229.2198.18.229.32
66198.18.229.4/30198.18.229.5 to 198.18.229.6198.18.229.72
67198.18.229.8/30198.18.229.9 to 198.18.229.10198.18.229.112
68198.18.229.12/30198.18.229.13 to 198.18.229.14198.18.229.152
69198.18.229.16/30198.18.229.17 to 198.18.229.18198.18.229.192
70198.18.229.20/30198.18.229.21 to 198.18.229.22198.18.229.232
71198.18.229.24/30198.18.229.25 to 198.18.229.26198.18.229.272
72198.18.229.28/30198.18.229.29 to 198.18.229.30198.18.229.312
73198.18.229.32/30198.18.229.33 to 198.18.229.34198.18.229.352
74198.18.229.36/30198.18.229.37 to 198.18.229.38198.18.229.392
75198.18.229.40/30198.18.229.41 to 198.18.229.42198.18.229.432
76198.18.229.44/30198.18.229.45 to 198.18.229.46198.18.229.472
77198.18.229.48/30198.18.229.49 to 198.18.229.50198.18.229.512
78198.18.229.52/30198.18.229.53 to 198.18.229.54198.18.229.552
79198.18.229.56/30198.18.229.57 to 198.18.229.58198.18.229.592
80198.18.229.60/30198.18.229.61 to 198.18.229.62198.18.229.632
81198.18.229.64/30198.18.229.65 to 198.18.229.66198.18.229.672
82198.18.229.68/30198.18.229.69 to 198.18.229.70198.18.229.712
83198.18.229.72/30198.18.229.73 to 198.18.229.74198.18.229.752
84198.18.229.76/30198.18.229.77 to 198.18.229.78198.18.229.792
85198.18.229.80/30198.18.229.81 to 198.18.229.82198.18.229.832
86198.18.229.84/30198.18.229.85 to 198.18.229.86198.18.229.872
87198.18.229.88/30198.18.229.89 to 198.18.229.90198.18.229.912
88198.18.229.92/30198.18.229.93 to 198.18.229.94198.18.229.952
89198.18.229.96/30198.18.229.97 to 198.18.229.98198.18.229.992
90198.18.229.100/30198.18.229.101 to 198.18.229.102198.18.229.1032
91198.18.229.104/30198.18.229.105 to 198.18.229.106198.18.229.1072
92198.18.229.108/30198.18.229.109 to 198.18.229.110198.18.229.1112
93198.18.229.112/30198.18.229.113 to 198.18.229.114198.18.229.1152
94198.18.229.116/30198.18.229.117 to 198.18.229.118198.18.229.1192
95198.18.229.120/30198.18.229.121 to 198.18.229.122198.18.229.1232
96198.18.229.124/30198.18.229.125 to 198.18.229.126198.18.229.1272
97198.18.229.128/30198.18.229.129 to 198.18.229.130198.18.229.1312
98198.18.229.132/30198.18.229.133 to 198.18.229.134198.18.229.1352
99198.18.229.136/30198.18.229.137 to 198.18.229.138198.18.229.1392
100198.18.229.140/30198.18.229.141 to 198.18.229.142198.18.229.1432
101198.18.229.144/30198.18.229.145 to 198.18.229.146198.18.229.1472
102198.18.229.148/30198.18.229.149 to 198.18.229.150198.18.229.1512
103198.18.229.152/30198.18.229.153 to 198.18.229.154198.18.229.1552
104198.18.229.156/30198.18.229.157 to 198.18.229.158198.18.229.1592
105198.18.229.160/30198.18.229.161 to 198.18.229.162198.18.229.1632
106198.18.229.164/30198.18.229.165 to 198.18.229.166198.18.229.1672
107198.18.229.168/30198.18.229.169 to 198.18.229.170198.18.229.1712
108198.18.229.172/30198.18.229.173 to 198.18.229.174198.18.229.1752
109198.18.229.176/30198.18.229.177 to 198.18.229.178198.18.229.1792
110198.18.229.180/30198.18.229.181 to 198.18.229.182198.18.229.1832
111198.18.229.184/30198.18.229.185 to 198.18.229.186198.18.229.1872
112198.18.229.188/30198.18.229.189 to 198.18.229.190198.18.229.1912
113198.18.229.192/30198.18.229.193 to 198.18.229.194198.18.229.1952
114198.18.229.196/30198.18.229.197 to 198.18.229.198198.18.229.1992
115198.18.229.200/30198.18.229.201 to 198.18.229.202198.18.229.2032
116198.18.229.204/30198.18.229.205 to 198.18.229.206198.18.229.2072
117198.18.229.208/30198.18.229.209 to 198.18.229.210198.18.229.2112
118198.18.229.212/30198.18.229.213 to 198.18.229.214198.18.229.2152
119198.18.229.216/30198.18.229.217 to 198.18.229.218198.18.229.2192
120198.18.229.220/30198.18.229.221 to 198.18.229.222198.18.229.2232
121198.18.229.224/30198.18.229.225 to 198.18.229.226198.18.229.2272
122198.18.229.228/30198.18.229.229 to 198.18.229.230198.18.229.2312
123198.18.229.232/30198.18.229.233 to 198.18.229.234198.18.229.2352
124198.18.229.236/30198.18.229.237 to 198.18.229.238198.18.229.2392
125198.18.229.240/30198.18.229.241 to 198.18.229.242198.18.229.2432
126198.18.229.244/30198.18.229.245 to 198.18.229.246198.18.229.2472
127198.18.229.248/30198.18.229.249 to 198.18.229.250198.18.229.2512
128198.18.229.252/30198.18.229.253 to 198.18.229.254198.18.229.2552
129198.18.230.0/30198.18.230.1 to 198.18.230.2198.18.230.32
130198.18.230.4/30198.18.230.5 to 198.18.230.6198.18.230.72
131198.18.230.8/30198.18.230.9 to 198.18.230.10198.18.230.112
132198.18.230.12/30198.18.230.13 to 198.18.230.14198.18.230.152
133198.18.230.16/30198.18.230.17 to 198.18.230.18198.18.230.192
134198.18.230.20/30198.18.230.21 to 198.18.230.22198.18.230.232
135198.18.230.24/30198.18.230.25 to 198.18.230.26198.18.230.272
136198.18.230.28/30198.18.230.29 to 198.18.230.30198.18.230.312
137198.18.230.32/30198.18.230.33 to 198.18.230.34198.18.230.352
138198.18.230.36/30198.18.230.37 to 198.18.230.38198.18.230.392
139198.18.230.40/30198.18.230.41 to 198.18.230.42198.18.230.432
140198.18.230.44/30198.18.230.45 to 198.18.230.46198.18.230.472
141198.18.230.48/30198.18.230.49 to 198.18.230.50198.18.230.512
142198.18.230.52/30198.18.230.53 to 198.18.230.54198.18.230.552
143198.18.230.56/30198.18.230.57 to 198.18.230.58198.18.230.592
144198.18.230.60/30198.18.230.61 to 198.18.230.62198.18.230.632
145198.18.230.64/30198.18.230.65 to 198.18.230.66198.18.230.672
146198.18.230.68/30198.18.230.69 to 198.18.230.70198.18.230.712
147198.18.230.72/30198.18.230.73 to 198.18.230.74198.18.230.752
148198.18.230.76/30198.18.230.77 to 198.18.230.78198.18.230.792
149198.18.230.80/30198.18.230.81 to 198.18.230.82198.18.230.832
150198.18.230.84/30198.18.230.85 to 198.18.230.86198.18.230.872
151198.18.230.88/30198.18.230.89 to 198.18.230.90198.18.230.912
152198.18.230.92/30198.18.230.93 to 198.18.230.94198.18.230.952
153198.18.230.96/30198.18.230.97 to 198.18.230.98198.18.230.992
154198.18.230.100/30198.18.230.101 to 198.18.230.102198.18.230.1032
155198.18.230.104/30198.18.230.105 to 198.18.230.106198.18.230.1072
156198.18.230.108/30198.18.230.109 to 198.18.230.110198.18.230.1112
157198.18.230.112/30198.18.230.113 to 198.18.230.114198.18.230.1152
158198.18.230.116/30198.18.230.117 to 198.18.230.118198.18.230.1192
159198.18.230.120/30198.18.230.121 to 198.18.230.122198.18.230.1232
160198.18.230.124/30198.18.230.125 to 198.18.230.126198.18.230.1272
161198.18.230.128/30198.18.230.129 to 198.18.230.130198.18.230.1312
162198.18.230.132/30198.18.230.133 to 198.18.230.134198.18.230.1352
163198.18.230.136/30198.18.230.137 to 198.18.230.138198.18.230.1392
164198.18.230.140/30198.18.230.141 to 198.18.230.142198.18.230.1432
165198.18.230.144/30198.18.230.145 to 198.18.230.146198.18.230.1472
166198.18.230.148/30198.18.230.149 to 198.18.230.150198.18.230.1512
167198.18.230.152/30198.18.230.153 to 198.18.230.154198.18.230.1552
168198.18.230.156/30198.18.230.157 to 198.18.230.158198.18.230.1592
169198.18.230.160/30198.18.230.161 to 198.18.230.162198.18.230.1632
170198.18.230.164/30198.18.230.165 to 198.18.230.166198.18.230.1672
171198.18.230.168/30198.18.230.169 to 198.18.230.170198.18.230.1712
172198.18.230.172/30198.18.230.173 to 198.18.230.174198.18.230.1752
173198.18.230.176/30198.18.230.177 to 198.18.230.178198.18.230.1792
174198.18.230.180/30198.18.230.181 to 198.18.230.182198.18.230.1832
175198.18.230.184/30198.18.230.185 to 198.18.230.186198.18.230.1872
176198.18.230.188/30198.18.230.189 to 198.18.230.190198.18.230.1912
177198.18.230.192/30198.18.230.193 to 198.18.230.194198.18.230.1952
178198.18.230.196/30198.18.230.197 to 198.18.230.198198.18.230.1992
179198.18.230.200/30198.18.230.201 to 198.18.230.202198.18.230.2032
180198.18.230.204/30198.18.230.205 to 198.18.230.206198.18.230.2072
181198.18.230.208/30198.18.230.209 to 198.18.230.210198.18.230.2112
182198.18.230.212/30198.18.230.213 to 198.18.230.214198.18.230.2152
183198.18.230.216/30198.18.230.217 to 198.18.230.218198.18.230.2192
184198.18.230.220/30198.18.230.221 to 198.18.230.222198.18.230.2232
185198.18.230.224/30198.18.230.225 to 198.18.230.226198.18.230.2272
186198.18.230.228/30198.18.230.229 to 198.18.230.230198.18.230.2312
187198.18.230.232/30198.18.230.233 to 198.18.230.234198.18.230.2352
188198.18.230.236/30198.18.230.237 to 198.18.230.238198.18.230.2392
189198.18.230.240/30198.18.230.241 to 198.18.230.242198.18.230.2432
190198.18.230.244/30198.18.230.245 to 198.18.230.246198.18.230.2472
191198.18.230.248/30198.18.230.249 to 198.18.230.250198.18.230.2512
192198.18.230.252/30198.18.230.253 to 198.18.230.254198.18.230.2552
193198.18.231.0/30198.18.231.1 to 198.18.231.2198.18.231.32
194198.18.231.4/30198.18.231.5 to 198.18.231.6198.18.231.72
195198.18.231.8/30198.18.231.9 to 198.18.231.10198.18.231.112
196198.18.231.12/30198.18.231.13 to 198.18.231.14198.18.231.152
197198.18.231.16/30198.18.231.17 to 198.18.231.18198.18.231.192
198198.18.231.20/30198.18.231.21 to 198.18.231.22198.18.231.232
199198.18.231.24/30198.18.231.25 to 198.18.231.26198.18.231.272
200198.18.231.28/30198.18.231.29 to 198.18.231.30198.18.231.312
201198.18.231.32/30198.18.231.33 to 198.18.231.34198.18.231.352
202198.18.231.36/30198.18.231.37 to 198.18.231.38198.18.231.392
203198.18.231.40/30198.18.231.41 to 198.18.231.42198.18.231.432
204198.18.231.44/30198.18.231.45 to 198.18.231.46198.18.231.472
205198.18.231.48/30198.18.231.49 to 198.18.231.50198.18.231.512
206198.18.231.52/30198.18.231.53 to 198.18.231.54198.18.231.552
207198.18.231.56/30198.18.231.57 to 198.18.231.58198.18.231.592
208198.18.231.60/30198.18.231.61 to 198.18.231.62198.18.231.632
209198.18.231.64/30198.18.231.65 to 198.18.231.66198.18.231.672
210198.18.231.68/30198.18.231.69 to 198.18.231.70198.18.231.712
211198.18.231.72/30198.18.231.73 to 198.18.231.74198.18.231.752
212198.18.231.76/30198.18.231.77 to 198.18.231.78198.18.231.792
213198.18.231.80/30198.18.231.81 to 198.18.231.82198.18.231.832
214198.18.231.84/30198.18.231.85 to 198.18.231.86198.18.231.872
215198.18.231.88/30198.18.231.89 to 198.18.231.90198.18.231.912
216198.18.231.92/30198.18.231.93 to 198.18.231.94198.18.231.952
217198.18.231.96/30198.18.231.97 to 198.18.231.98198.18.231.992
218198.18.231.100/30198.18.231.101 to 198.18.231.102198.18.231.1032
219198.18.231.104/30198.18.231.105 to 198.18.231.106198.18.231.1072
220198.18.231.108/30198.18.231.109 to 198.18.231.110198.18.231.1112
221198.18.231.112/30198.18.231.113 to 198.18.231.114198.18.231.1152
222198.18.231.116/30198.18.231.117 to 198.18.231.118198.18.231.1192
223198.18.231.120/30198.18.231.121 to 198.18.231.122198.18.231.1232
224198.18.231.124/30198.18.231.125 to 198.18.231.126198.18.231.1272
225198.18.231.128/30198.18.231.129 to 198.18.231.130198.18.231.1312
226198.18.231.132/30198.18.231.133 to 198.18.231.134198.18.231.1352
227198.18.231.136/30198.18.231.137 to 198.18.231.138198.18.231.1392
228198.18.231.140/30198.18.231.141 to 198.18.231.142198.18.231.1432
229198.18.231.144/30198.18.231.145 to 198.18.231.146198.18.231.1472
230198.18.231.148/30198.18.231.149 to 198.18.231.150198.18.231.1512
231198.18.231.152/30198.18.231.153 to 198.18.231.154198.18.231.1552
232198.18.231.156/30198.18.231.157 to 198.18.231.158198.18.231.1592
233198.18.231.160/30198.18.231.161 to 198.18.231.162198.18.231.1632
234198.18.231.164/30198.18.231.165 to 198.18.231.166198.18.231.1672
235198.18.231.168/30198.18.231.169 to 198.18.231.170198.18.231.1712
236198.18.231.172/30198.18.231.173 to 198.18.231.174198.18.231.1752
237198.18.231.176/30198.18.231.177 to 198.18.231.178198.18.231.1792
238198.18.231.180/30198.18.231.181 to 198.18.231.182198.18.231.1832
239198.18.231.184/30198.18.231.185 to 198.18.231.186198.18.231.1872
240198.18.231.188/30198.18.231.189 to 198.18.231.190198.18.231.1912
241198.18.231.192/30198.18.231.193 to 198.18.231.194198.18.231.1952
242198.18.231.196/30198.18.231.197 to 198.18.231.198198.18.231.1992
243198.18.231.200/30198.18.231.201 to 198.18.231.202198.18.231.2032
244198.18.231.204/30198.18.231.205 to 198.18.231.206198.18.231.2072
245198.18.231.208/30198.18.231.209 to 198.18.231.210198.18.231.2112
246198.18.231.212/30198.18.231.213 to 198.18.231.214198.18.231.2152
247198.18.231.216/30198.18.231.217 to 198.18.231.218198.18.231.2192
248198.18.231.220/30198.18.231.221 to 198.18.231.222198.18.231.2232
249198.18.231.224/30198.18.231.225 to 198.18.231.226198.18.231.2272
250198.18.231.228/30198.18.231.229 to 198.18.231.230198.18.231.2312
251198.18.231.232/30198.18.231.233 to 198.18.231.234198.18.231.2352
252198.18.231.236/30198.18.231.237 to 198.18.231.238198.18.231.2392
253198.18.231.240/30198.18.231.241 to 198.18.231.242198.18.231.2432
254198.18.231.244/30198.18.231.245 to 198.18.231.246198.18.231.2472
255198.18.231.248/30198.18.231.249 to 198.18.231.250198.18.231.2512
256198.18.231.252/30198.18.231.253 to 198.18.231.254198.18.231.2552

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.