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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.

Network114.3.192.0/19
Usable hosts8,190
Subnet mask255.255.224.0
Addresses8,192
Network address
114.3.192.0
Broadcast address
114.3.223.255
First usable
114.3.192.1
Last usable
114.3.223.254
Usable hosts
8,190 (8,192 less the network and broadcast addresses)
Subnet mask
255.255.224.0
Wildcard mask
0.0.31.255 (Cisco ACLs, OSPF)
Prefix length
/19
Type
Public public
Old class
A (default /8)
As numbers
Hex 7203C000 · Integer 1912848384 to 1912856575
Reverse DNS zones
192.3.114.in-addr.arpa
193.3.114.in-addr.arpa
194.3.114.in-addr.arpa
195.3.114.in-addr.arpa
196.3.114.in-addr.arpa
197.3.114.in-addr.arpa
198.3.114.in-addr.arpa
199.3.114.in-addr.arpa
200.3.114.in-addr.arpa
201.3.114.in-addr.arpa
202.3.114.in-addr.arpa
203.3.114.in-addr.arpa
204.3.114.in-addr.arpa
205.3.114.in-addr.arpa
206.3.114.in-addr.arpa
207.3.114.in-addr.arpa
and 16 more
/19 is not on a 8-bit boundary, so it takes 32 /24 zones.
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address01110010.00000011.11000000.00000000114.3.192.0
Subnet mask11111111.11111111.11100000.00000000255.255.224.0
Network01110010.00000011.11000000.00000000114.3.192.0
Broadcast01110010.00000011.11011111.11111111114.3.223.255
Split into smaller subnets/30
/20 (2)/21 (4)/22 (8)/23 (16)/24 (32)/25 (64)/26 (128)/27 (256)/28 (512)/29 (1,024)/30 (2,048)/31 (4,096)

114.3.192.0/19 makes 2,048 subnets of /30; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
1114.3.192.0/30114.3.192.1 to 114.3.192.2114.3.192.32
2114.3.192.4/30114.3.192.5 to 114.3.192.6114.3.192.72
3114.3.192.8/30114.3.192.9 to 114.3.192.10114.3.192.112
4114.3.192.12/30114.3.192.13 to 114.3.192.14114.3.192.152
5114.3.192.16/30114.3.192.17 to 114.3.192.18114.3.192.192
6114.3.192.20/30114.3.192.21 to 114.3.192.22114.3.192.232
7114.3.192.24/30114.3.192.25 to 114.3.192.26114.3.192.272
8114.3.192.28/30114.3.192.29 to 114.3.192.30114.3.192.312
9114.3.192.32/30114.3.192.33 to 114.3.192.34114.3.192.352
10114.3.192.36/30114.3.192.37 to 114.3.192.38114.3.192.392
11114.3.192.40/30114.3.192.41 to 114.3.192.42114.3.192.432
12114.3.192.44/30114.3.192.45 to 114.3.192.46114.3.192.472
13114.3.192.48/30114.3.192.49 to 114.3.192.50114.3.192.512
14114.3.192.52/30114.3.192.53 to 114.3.192.54114.3.192.552
15114.3.192.56/30114.3.192.57 to 114.3.192.58114.3.192.592
16114.3.192.60/30114.3.192.61 to 114.3.192.62114.3.192.632
17114.3.192.64/30114.3.192.65 to 114.3.192.66114.3.192.672
18114.3.192.68/30114.3.192.69 to 114.3.192.70114.3.192.712
19114.3.192.72/30114.3.192.73 to 114.3.192.74114.3.192.752
20114.3.192.76/30114.3.192.77 to 114.3.192.78114.3.192.792
21114.3.192.80/30114.3.192.81 to 114.3.192.82114.3.192.832
22114.3.192.84/30114.3.192.85 to 114.3.192.86114.3.192.872
23114.3.192.88/30114.3.192.89 to 114.3.192.90114.3.192.912
24114.3.192.92/30114.3.192.93 to 114.3.192.94114.3.192.952
25114.3.192.96/30114.3.192.97 to 114.3.192.98114.3.192.992
26114.3.192.100/30114.3.192.101 to 114.3.192.102114.3.192.1032
27114.3.192.104/30114.3.192.105 to 114.3.192.106114.3.192.1072
28114.3.192.108/30114.3.192.109 to 114.3.192.110114.3.192.1112
29114.3.192.112/30114.3.192.113 to 114.3.192.114114.3.192.1152
30114.3.192.116/30114.3.192.117 to 114.3.192.118114.3.192.1192
31114.3.192.120/30114.3.192.121 to 114.3.192.122114.3.192.1232
32114.3.192.124/30114.3.192.125 to 114.3.192.126114.3.192.1272
33114.3.192.128/30114.3.192.129 to 114.3.192.130114.3.192.1312
34114.3.192.132/30114.3.192.133 to 114.3.192.134114.3.192.1352
35114.3.192.136/30114.3.192.137 to 114.3.192.138114.3.192.1392
36114.3.192.140/30114.3.192.141 to 114.3.192.142114.3.192.1432
37114.3.192.144/30114.3.192.145 to 114.3.192.146114.3.192.1472
38114.3.192.148/30114.3.192.149 to 114.3.192.150114.3.192.1512
39114.3.192.152/30114.3.192.153 to 114.3.192.154114.3.192.1552
40114.3.192.156/30114.3.192.157 to 114.3.192.158114.3.192.1592
41114.3.192.160/30114.3.192.161 to 114.3.192.162114.3.192.1632
42114.3.192.164/30114.3.192.165 to 114.3.192.166114.3.192.1672
43114.3.192.168/30114.3.192.169 to 114.3.192.170114.3.192.1712
44114.3.192.172/30114.3.192.173 to 114.3.192.174114.3.192.1752
45114.3.192.176/30114.3.192.177 to 114.3.192.178114.3.192.1792
46114.3.192.180/30114.3.192.181 to 114.3.192.182114.3.192.1832
47114.3.192.184/30114.3.192.185 to 114.3.192.186114.3.192.1872
48114.3.192.188/30114.3.192.189 to 114.3.192.190114.3.192.1912
49114.3.192.192/30114.3.192.193 to 114.3.192.194114.3.192.1952
50114.3.192.196/30114.3.192.197 to 114.3.192.198114.3.192.1992
51114.3.192.200/30114.3.192.201 to 114.3.192.202114.3.192.2032
52114.3.192.204/30114.3.192.205 to 114.3.192.206114.3.192.2072
53114.3.192.208/30114.3.192.209 to 114.3.192.210114.3.192.2112
54114.3.192.212/30114.3.192.213 to 114.3.192.214114.3.192.2152
55114.3.192.216/30114.3.192.217 to 114.3.192.218114.3.192.2192
56114.3.192.220/30114.3.192.221 to 114.3.192.222114.3.192.2232
57114.3.192.224/30114.3.192.225 to 114.3.192.226114.3.192.2272
58114.3.192.228/30114.3.192.229 to 114.3.192.230114.3.192.2312
59114.3.192.232/30114.3.192.233 to 114.3.192.234114.3.192.2352
60114.3.192.236/30114.3.192.237 to 114.3.192.238114.3.192.2392
61114.3.192.240/30114.3.192.241 to 114.3.192.242114.3.192.2432
62114.3.192.244/30114.3.192.245 to 114.3.192.246114.3.192.2472
63114.3.192.248/30114.3.192.249 to 114.3.192.250114.3.192.2512
64114.3.192.252/30114.3.192.253 to 114.3.192.254114.3.192.2552
65114.3.193.0/30114.3.193.1 to 114.3.193.2114.3.193.32
66114.3.193.4/30114.3.193.5 to 114.3.193.6114.3.193.72
67114.3.193.8/30114.3.193.9 to 114.3.193.10114.3.193.112
68114.3.193.12/30114.3.193.13 to 114.3.193.14114.3.193.152
69114.3.193.16/30114.3.193.17 to 114.3.193.18114.3.193.192
70114.3.193.20/30114.3.193.21 to 114.3.193.22114.3.193.232
71114.3.193.24/30114.3.193.25 to 114.3.193.26114.3.193.272
72114.3.193.28/30114.3.193.29 to 114.3.193.30114.3.193.312
73114.3.193.32/30114.3.193.33 to 114.3.193.34114.3.193.352
74114.3.193.36/30114.3.193.37 to 114.3.193.38114.3.193.392
75114.3.193.40/30114.3.193.41 to 114.3.193.42114.3.193.432
76114.3.193.44/30114.3.193.45 to 114.3.193.46114.3.193.472
77114.3.193.48/30114.3.193.49 to 114.3.193.50114.3.193.512
78114.3.193.52/30114.3.193.53 to 114.3.193.54114.3.193.552
79114.3.193.56/30114.3.193.57 to 114.3.193.58114.3.193.592
80114.3.193.60/30114.3.193.61 to 114.3.193.62114.3.193.632
81114.3.193.64/30114.3.193.65 to 114.3.193.66114.3.193.672
82114.3.193.68/30114.3.193.69 to 114.3.193.70114.3.193.712
83114.3.193.72/30114.3.193.73 to 114.3.193.74114.3.193.752
84114.3.193.76/30114.3.193.77 to 114.3.193.78114.3.193.792
85114.3.193.80/30114.3.193.81 to 114.3.193.82114.3.193.832
86114.3.193.84/30114.3.193.85 to 114.3.193.86114.3.193.872
87114.3.193.88/30114.3.193.89 to 114.3.193.90114.3.193.912
88114.3.193.92/30114.3.193.93 to 114.3.193.94114.3.193.952
89114.3.193.96/30114.3.193.97 to 114.3.193.98114.3.193.992
90114.3.193.100/30114.3.193.101 to 114.3.193.102114.3.193.1032
91114.3.193.104/30114.3.193.105 to 114.3.193.106114.3.193.1072
92114.3.193.108/30114.3.193.109 to 114.3.193.110114.3.193.1112
93114.3.193.112/30114.3.193.113 to 114.3.193.114114.3.193.1152
94114.3.193.116/30114.3.193.117 to 114.3.193.118114.3.193.1192
95114.3.193.120/30114.3.193.121 to 114.3.193.122114.3.193.1232
96114.3.193.124/30114.3.193.125 to 114.3.193.126114.3.193.1272
97114.3.193.128/30114.3.193.129 to 114.3.193.130114.3.193.1312
98114.3.193.132/30114.3.193.133 to 114.3.193.134114.3.193.1352
99114.3.193.136/30114.3.193.137 to 114.3.193.138114.3.193.1392
100114.3.193.140/30114.3.193.141 to 114.3.193.142114.3.193.1432
101114.3.193.144/30114.3.193.145 to 114.3.193.146114.3.193.1472
102114.3.193.148/30114.3.193.149 to 114.3.193.150114.3.193.1512
103114.3.193.152/30114.3.193.153 to 114.3.193.154114.3.193.1552
104114.3.193.156/30114.3.193.157 to 114.3.193.158114.3.193.1592
105114.3.193.160/30114.3.193.161 to 114.3.193.162114.3.193.1632
106114.3.193.164/30114.3.193.165 to 114.3.193.166114.3.193.1672
107114.3.193.168/30114.3.193.169 to 114.3.193.170114.3.193.1712
108114.3.193.172/30114.3.193.173 to 114.3.193.174114.3.193.1752
109114.3.193.176/30114.3.193.177 to 114.3.193.178114.3.193.1792
110114.3.193.180/30114.3.193.181 to 114.3.193.182114.3.193.1832
111114.3.193.184/30114.3.193.185 to 114.3.193.186114.3.193.1872
112114.3.193.188/30114.3.193.189 to 114.3.193.190114.3.193.1912
113114.3.193.192/30114.3.193.193 to 114.3.193.194114.3.193.1952
114114.3.193.196/30114.3.193.197 to 114.3.193.198114.3.193.1992
115114.3.193.200/30114.3.193.201 to 114.3.193.202114.3.193.2032
116114.3.193.204/30114.3.193.205 to 114.3.193.206114.3.193.2072
117114.3.193.208/30114.3.193.209 to 114.3.193.210114.3.193.2112
118114.3.193.212/30114.3.193.213 to 114.3.193.214114.3.193.2152
119114.3.193.216/30114.3.193.217 to 114.3.193.218114.3.193.2192
120114.3.193.220/30114.3.193.221 to 114.3.193.222114.3.193.2232
121114.3.193.224/30114.3.193.225 to 114.3.193.226114.3.193.2272
122114.3.193.228/30114.3.193.229 to 114.3.193.230114.3.193.2312
123114.3.193.232/30114.3.193.233 to 114.3.193.234114.3.193.2352
124114.3.193.236/30114.3.193.237 to 114.3.193.238114.3.193.2392
125114.3.193.240/30114.3.193.241 to 114.3.193.242114.3.193.2432
126114.3.193.244/30114.3.193.245 to 114.3.193.246114.3.193.2472
127114.3.193.248/30114.3.193.249 to 114.3.193.250114.3.193.2512
128114.3.193.252/30114.3.193.253 to 114.3.193.254114.3.193.2552
129114.3.194.0/30114.3.194.1 to 114.3.194.2114.3.194.32
130114.3.194.4/30114.3.194.5 to 114.3.194.6114.3.194.72
131114.3.194.8/30114.3.194.9 to 114.3.194.10114.3.194.112
132114.3.194.12/30114.3.194.13 to 114.3.194.14114.3.194.152
133114.3.194.16/30114.3.194.17 to 114.3.194.18114.3.194.192
134114.3.194.20/30114.3.194.21 to 114.3.194.22114.3.194.232
135114.3.194.24/30114.3.194.25 to 114.3.194.26114.3.194.272
136114.3.194.28/30114.3.194.29 to 114.3.194.30114.3.194.312
137114.3.194.32/30114.3.194.33 to 114.3.194.34114.3.194.352
138114.3.194.36/30114.3.194.37 to 114.3.194.38114.3.194.392
139114.3.194.40/30114.3.194.41 to 114.3.194.42114.3.194.432
140114.3.194.44/30114.3.194.45 to 114.3.194.46114.3.194.472
141114.3.194.48/30114.3.194.49 to 114.3.194.50114.3.194.512
142114.3.194.52/30114.3.194.53 to 114.3.194.54114.3.194.552
143114.3.194.56/30114.3.194.57 to 114.3.194.58114.3.194.592
144114.3.194.60/30114.3.194.61 to 114.3.194.62114.3.194.632
145114.3.194.64/30114.3.194.65 to 114.3.194.66114.3.194.672
146114.3.194.68/30114.3.194.69 to 114.3.194.70114.3.194.712
147114.3.194.72/30114.3.194.73 to 114.3.194.74114.3.194.752
148114.3.194.76/30114.3.194.77 to 114.3.194.78114.3.194.792
149114.3.194.80/30114.3.194.81 to 114.3.194.82114.3.194.832
150114.3.194.84/30114.3.194.85 to 114.3.194.86114.3.194.872
151114.3.194.88/30114.3.194.89 to 114.3.194.90114.3.194.912
152114.3.194.92/30114.3.194.93 to 114.3.194.94114.3.194.952
153114.3.194.96/30114.3.194.97 to 114.3.194.98114.3.194.992
154114.3.194.100/30114.3.194.101 to 114.3.194.102114.3.194.1032
155114.3.194.104/30114.3.194.105 to 114.3.194.106114.3.194.1072
156114.3.194.108/30114.3.194.109 to 114.3.194.110114.3.194.1112
157114.3.194.112/30114.3.194.113 to 114.3.194.114114.3.194.1152
158114.3.194.116/30114.3.194.117 to 114.3.194.118114.3.194.1192
159114.3.194.120/30114.3.194.121 to 114.3.194.122114.3.194.1232
160114.3.194.124/30114.3.194.125 to 114.3.194.126114.3.194.1272
161114.3.194.128/30114.3.194.129 to 114.3.194.130114.3.194.1312
162114.3.194.132/30114.3.194.133 to 114.3.194.134114.3.194.1352
163114.3.194.136/30114.3.194.137 to 114.3.194.138114.3.194.1392
164114.3.194.140/30114.3.194.141 to 114.3.194.142114.3.194.1432
165114.3.194.144/30114.3.194.145 to 114.3.194.146114.3.194.1472
166114.3.194.148/30114.3.194.149 to 114.3.194.150114.3.194.1512
167114.3.194.152/30114.3.194.153 to 114.3.194.154114.3.194.1552
168114.3.194.156/30114.3.194.157 to 114.3.194.158114.3.194.1592
169114.3.194.160/30114.3.194.161 to 114.3.194.162114.3.194.1632
170114.3.194.164/30114.3.194.165 to 114.3.194.166114.3.194.1672
171114.3.194.168/30114.3.194.169 to 114.3.194.170114.3.194.1712
172114.3.194.172/30114.3.194.173 to 114.3.194.174114.3.194.1752
173114.3.194.176/30114.3.194.177 to 114.3.194.178114.3.194.1792
174114.3.194.180/30114.3.194.181 to 114.3.194.182114.3.194.1832
175114.3.194.184/30114.3.194.185 to 114.3.194.186114.3.194.1872
176114.3.194.188/30114.3.194.189 to 114.3.194.190114.3.194.1912
177114.3.194.192/30114.3.194.193 to 114.3.194.194114.3.194.1952
178114.3.194.196/30114.3.194.197 to 114.3.194.198114.3.194.1992
179114.3.194.200/30114.3.194.201 to 114.3.194.202114.3.194.2032
180114.3.194.204/30114.3.194.205 to 114.3.194.206114.3.194.2072
181114.3.194.208/30114.3.194.209 to 114.3.194.210114.3.194.2112
182114.3.194.212/30114.3.194.213 to 114.3.194.214114.3.194.2152
183114.3.194.216/30114.3.194.217 to 114.3.194.218114.3.194.2192
184114.3.194.220/30114.3.194.221 to 114.3.194.222114.3.194.2232
185114.3.194.224/30114.3.194.225 to 114.3.194.226114.3.194.2272
186114.3.194.228/30114.3.194.229 to 114.3.194.230114.3.194.2312
187114.3.194.232/30114.3.194.233 to 114.3.194.234114.3.194.2352
188114.3.194.236/30114.3.194.237 to 114.3.194.238114.3.194.2392
189114.3.194.240/30114.3.194.241 to 114.3.194.242114.3.194.2432
190114.3.194.244/30114.3.194.245 to 114.3.194.246114.3.194.2472
191114.3.194.248/30114.3.194.249 to 114.3.194.250114.3.194.2512
192114.3.194.252/30114.3.194.253 to 114.3.194.254114.3.194.2552
193114.3.195.0/30114.3.195.1 to 114.3.195.2114.3.195.32
194114.3.195.4/30114.3.195.5 to 114.3.195.6114.3.195.72
195114.3.195.8/30114.3.195.9 to 114.3.195.10114.3.195.112
196114.3.195.12/30114.3.195.13 to 114.3.195.14114.3.195.152
197114.3.195.16/30114.3.195.17 to 114.3.195.18114.3.195.192
198114.3.195.20/30114.3.195.21 to 114.3.195.22114.3.195.232
199114.3.195.24/30114.3.195.25 to 114.3.195.26114.3.195.272
200114.3.195.28/30114.3.195.29 to 114.3.195.30114.3.195.312
201114.3.195.32/30114.3.195.33 to 114.3.195.34114.3.195.352
202114.3.195.36/30114.3.195.37 to 114.3.195.38114.3.195.392
203114.3.195.40/30114.3.195.41 to 114.3.195.42114.3.195.432
204114.3.195.44/30114.3.195.45 to 114.3.195.46114.3.195.472
205114.3.195.48/30114.3.195.49 to 114.3.195.50114.3.195.512
206114.3.195.52/30114.3.195.53 to 114.3.195.54114.3.195.552
207114.3.195.56/30114.3.195.57 to 114.3.195.58114.3.195.592
208114.3.195.60/30114.3.195.61 to 114.3.195.62114.3.195.632
209114.3.195.64/30114.3.195.65 to 114.3.195.66114.3.195.672
210114.3.195.68/30114.3.195.69 to 114.3.195.70114.3.195.712
211114.3.195.72/30114.3.195.73 to 114.3.195.74114.3.195.752
212114.3.195.76/30114.3.195.77 to 114.3.195.78114.3.195.792
213114.3.195.80/30114.3.195.81 to 114.3.195.82114.3.195.832
214114.3.195.84/30114.3.195.85 to 114.3.195.86114.3.195.872
215114.3.195.88/30114.3.195.89 to 114.3.195.90114.3.195.912
216114.3.195.92/30114.3.195.93 to 114.3.195.94114.3.195.952
217114.3.195.96/30114.3.195.97 to 114.3.195.98114.3.195.992
218114.3.195.100/30114.3.195.101 to 114.3.195.102114.3.195.1032
219114.3.195.104/30114.3.195.105 to 114.3.195.106114.3.195.1072
220114.3.195.108/30114.3.195.109 to 114.3.195.110114.3.195.1112
221114.3.195.112/30114.3.195.113 to 114.3.195.114114.3.195.1152
222114.3.195.116/30114.3.195.117 to 114.3.195.118114.3.195.1192
223114.3.195.120/30114.3.195.121 to 114.3.195.122114.3.195.1232
224114.3.195.124/30114.3.195.125 to 114.3.195.126114.3.195.1272
225114.3.195.128/30114.3.195.129 to 114.3.195.130114.3.195.1312
226114.3.195.132/30114.3.195.133 to 114.3.195.134114.3.195.1352
227114.3.195.136/30114.3.195.137 to 114.3.195.138114.3.195.1392
228114.3.195.140/30114.3.195.141 to 114.3.195.142114.3.195.1432
229114.3.195.144/30114.3.195.145 to 114.3.195.146114.3.195.1472
230114.3.195.148/30114.3.195.149 to 114.3.195.150114.3.195.1512
231114.3.195.152/30114.3.195.153 to 114.3.195.154114.3.195.1552
232114.3.195.156/30114.3.195.157 to 114.3.195.158114.3.195.1592
233114.3.195.160/30114.3.195.161 to 114.3.195.162114.3.195.1632
234114.3.195.164/30114.3.195.165 to 114.3.195.166114.3.195.1672
235114.3.195.168/30114.3.195.169 to 114.3.195.170114.3.195.1712
236114.3.195.172/30114.3.195.173 to 114.3.195.174114.3.195.1752
237114.3.195.176/30114.3.195.177 to 114.3.195.178114.3.195.1792
238114.3.195.180/30114.3.195.181 to 114.3.195.182114.3.195.1832
239114.3.195.184/30114.3.195.185 to 114.3.195.186114.3.195.1872
240114.3.195.188/30114.3.195.189 to 114.3.195.190114.3.195.1912
241114.3.195.192/30114.3.195.193 to 114.3.195.194114.3.195.1952
242114.3.195.196/30114.3.195.197 to 114.3.195.198114.3.195.1992
243114.3.195.200/30114.3.195.201 to 114.3.195.202114.3.195.2032
244114.3.195.204/30114.3.195.205 to 114.3.195.206114.3.195.2072
245114.3.195.208/30114.3.195.209 to 114.3.195.210114.3.195.2112
246114.3.195.212/30114.3.195.213 to 114.3.195.214114.3.195.2152
247114.3.195.216/30114.3.195.217 to 114.3.195.218114.3.195.2192
248114.3.195.220/30114.3.195.221 to 114.3.195.222114.3.195.2232
249114.3.195.224/30114.3.195.225 to 114.3.195.226114.3.195.2272
250114.3.195.228/30114.3.195.229 to 114.3.195.230114.3.195.2312
251114.3.195.232/30114.3.195.233 to 114.3.195.234114.3.195.2352
252114.3.195.236/30114.3.195.237 to 114.3.195.238114.3.195.2392
253114.3.195.240/30114.3.195.241 to 114.3.195.242114.3.195.2432
254114.3.195.244/30114.3.195.245 to 114.3.195.246114.3.195.2472
255114.3.195.248/30114.3.195.249 to 114.3.195.250114.3.195.2512
256114.3.195.252/30114.3.195.253 to 114.3.195.254114.3.195.2552

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.