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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.

Network194.0.0.0/8
Usable hosts16,777,214
Subnet mask255.0.0.0
Addresses16,777,216
Network address
194.0.0.0
Broadcast address
194.255.255.255
First usable
194.0.0.1
Last usable
194.255.255.254
Usable hosts
16,777,214 (16,777,216 less the network and broadcast addresses)
Subnet mask
255.0.0.0
Wildcard mask
0.255.255.255 (Cisco ACLs, OSPF)
Prefix length
/8
Type
Public public
Old class
C (default /24)
As numbers
Hex C2000000 · Integer 3254779904 to 3271557119
Reverse DNS zone
194.in-addr.arpa
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address11000010..00000000.00000000.00000000194.0.0.0
Subnet mask11111111..00000000.00000000.00000000255.0.0.0
Network11000010..00000000.00000000.00000000194.0.0.0
Broadcast11000010..11111111.11111111.11111111194.255.255.255
Split into smaller subnets/18
/9 (2)/10 (4)/11 (8)/12 (16)/13 (32)/14 (64)/15 (128)/16 (256)/17 (512)/18 (1,024)/19 (2,048)/20 (4,096)

194.0.0.0/8 makes 1,024 subnets of /18; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
1194.0.0.0/18194.0.0.1 to 194.0.63.254194.0.63.25516,382
2194.0.64.0/18194.0.64.1 to 194.0.127.254194.0.127.25516,382
3194.0.128.0/18194.0.128.1 to 194.0.191.254194.0.191.25516,382
4194.0.192.0/18194.0.192.1 to 194.0.255.254194.0.255.25516,382
5194.1.0.0/18194.1.0.1 to 194.1.63.254194.1.63.25516,382
6194.1.64.0/18194.1.64.1 to 194.1.127.254194.1.127.25516,382
7194.1.128.0/18194.1.128.1 to 194.1.191.254194.1.191.25516,382
8194.1.192.0/18194.1.192.1 to 194.1.255.254194.1.255.25516,382
9194.2.0.0/18194.2.0.1 to 194.2.63.254194.2.63.25516,382
10194.2.64.0/18194.2.64.1 to 194.2.127.254194.2.127.25516,382
11194.2.128.0/18194.2.128.1 to 194.2.191.254194.2.191.25516,382
12194.2.192.0/18194.2.192.1 to 194.2.255.254194.2.255.25516,382
13194.3.0.0/18194.3.0.1 to 194.3.63.254194.3.63.25516,382
14194.3.64.0/18194.3.64.1 to 194.3.127.254194.3.127.25516,382
15194.3.128.0/18194.3.128.1 to 194.3.191.254194.3.191.25516,382
16194.3.192.0/18194.3.192.1 to 194.3.255.254194.3.255.25516,382
17194.4.0.0/18194.4.0.1 to 194.4.63.254194.4.63.25516,382
18194.4.64.0/18194.4.64.1 to 194.4.127.254194.4.127.25516,382
19194.4.128.0/18194.4.128.1 to 194.4.191.254194.4.191.25516,382
20194.4.192.0/18194.4.192.1 to 194.4.255.254194.4.255.25516,382
21194.5.0.0/18194.5.0.1 to 194.5.63.254194.5.63.25516,382
22194.5.64.0/18194.5.64.1 to 194.5.127.254194.5.127.25516,382
23194.5.128.0/18194.5.128.1 to 194.5.191.254194.5.191.25516,382
24194.5.192.0/18194.5.192.1 to 194.5.255.254194.5.255.25516,382
25194.6.0.0/18194.6.0.1 to 194.6.63.254194.6.63.25516,382
26194.6.64.0/18194.6.64.1 to 194.6.127.254194.6.127.25516,382
27194.6.128.0/18194.6.128.1 to 194.6.191.254194.6.191.25516,382
28194.6.192.0/18194.6.192.1 to 194.6.255.254194.6.255.25516,382
29194.7.0.0/18194.7.0.1 to 194.7.63.254194.7.63.25516,382
30194.7.64.0/18194.7.64.1 to 194.7.127.254194.7.127.25516,382
31194.7.128.0/18194.7.128.1 to 194.7.191.254194.7.191.25516,382
32194.7.192.0/18194.7.192.1 to 194.7.255.254194.7.255.25516,382
33194.8.0.0/18194.8.0.1 to 194.8.63.254194.8.63.25516,382
34194.8.64.0/18194.8.64.1 to 194.8.127.254194.8.127.25516,382
35194.8.128.0/18194.8.128.1 to 194.8.191.254194.8.191.25516,382
36194.8.192.0/18194.8.192.1 to 194.8.255.254194.8.255.25516,382
37194.9.0.0/18194.9.0.1 to 194.9.63.254194.9.63.25516,382
38194.9.64.0/18194.9.64.1 to 194.9.127.254194.9.127.25516,382
39194.9.128.0/18194.9.128.1 to 194.9.191.254194.9.191.25516,382
40194.9.192.0/18194.9.192.1 to 194.9.255.254194.9.255.25516,382
41194.10.0.0/18194.10.0.1 to 194.10.63.254194.10.63.25516,382
42194.10.64.0/18194.10.64.1 to 194.10.127.254194.10.127.25516,382
43194.10.128.0/18194.10.128.1 to 194.10.191.254194.10.191.25516,382
44194.10.192.0/18194.10.192.1 to 194.10.255.254194.10.255.25516,382
45194.11.0.0/18194.11.0.1 to 194.11.63.254194.11.63.25516,382
46194.11.64.0/18194.11.64.1 to 194.11.127.254194.11.127.25516,382
47194.11.128.0/18194.11.128.1 to 194.11.191.254194.11.191.25516,382
48194.11.192.0/18194.11.192.1 to 194.11.255.254194.11.255.25516,382
49194.12.0.0/18194.12.0.1 to 194.12.63.254194.12.63.25516,382
50194.12.64.0/18194.12.64.1 to 194.12.127.254194.12.127.25516,382
51194.12.128.0/18194.12.128.1 to 194.12.191.254194.12.191.25516,382
52194.12.192.0/18194.12.192.1 to 194.12.255.254194.12.255.25516,382
53194.13.0.0/18194.13.0.1 to 194.13.63.254194.13.63.25516,382
54194.13.64.0/18194.13.64.1 to 194.13.127.254194.13.127.25516,382
55194.13.128.0/18194.13.128.1 to 194.13.191.254194.13.191.25516,382
56194.13.192.0/18194.13.192.1 to 194.13.255.254194.13.255.25516,382
57194.14.0.0/18194.14.0.1 to 194.14.63.254194.14.63.25516,382
58194.14.64.0/18194.14.64.1 to 194.14.127.254194.14.127.25516,382
59194.14.128.0/18194.14.128.1 to 194.14.191.254194.14.191.25516,382
60194.14.192.0/18194.14.192.1 to 194.14.255.254194.14.255.25516,382
61194.15.0.0/18194.15.0.1 to 194.15.63.254194.15.63.25516,382
62194.15.64.0/18194.15.64.1 to 194.15.127.254194.15.127.25516,382
63194.15.128.0/18194.15.128.1 to 194.15.191.254194.15.191.25516,382
64194.15.192.0/18194.15.192.1 to 194.15.255.254194.15.255.25516,382
65194.16.0.0/18194.16.0.1 to 194.16.63.254194.16.63.25516,382
66194.16.64.0/18194.16.64.1 to 194.16.127.254194.16.127.25516,382
67194.16.128.0/18194.16.128.1 to 194.16.191.254194.16.191.25516,382
68194.16.192.0/18194.16.192.1 to 194.16.255.254194.16.255.25516,382
69194.17.0.0/18194.17.0.1 to 194.17.63.254194.17.63.25516,382
70194.17.64.0/18194.17.64.1 to 194.17.127.254194.17.127.25516,382
71194.17.128.0/18194.17.128.1 to 194.17.191.254194.17.191.25516,382
72194.17.192.0/18194.17.192.1 to 194.17.255.254194.17.255.25516,382
73194.18.0.0/18194.18.0.1 to 194.18.63.254194.18.63.25516,382
74194.18.64.0/18194.18.64.1 to 194.18.127.254194.18.127.25516,382
75194.18.128.0/18194.18.128.1 to 194.18.191.254194.18.191.25516,382
76194.18.192.0/18194.18.192.1 to 194.18.255.254194.18.255.25516,382
77194.19.0.0/18194.19.0.1 to 194.19.63.254194.19.63.25516,382
78194.19.64.0/18194.19.64.1 to 194.19.127.254194.19.127.25516,382
79194.19.128.0/18194.19.128.1 to 194.19.191.254194.19.191.25516,382
80194.19.192.0/18194.19.192.1 to 194.19.255.254194.19.255.25516,382
81194.20.0.0/18194.20.0.1 to 194.20.63.254194.20.63.25516,382
82194.20.64.0/18194.20.64.1 to 194.20.127.254194.20.127.25516,382
83194.20.128.0/18194.20.128.1 to 194.20.191.254194.20.191.25516,382
84194.20.192.0/18194.20.192.1 to 194.20.255.254194.20.255.25516,382
85194.21.0.0/18194.21.0.1 to 194.21.63.254194.21.63.25516,382
86194.21.64.0/18194.21.64.1 to 194.21.127.254194.21.127.25516,382
87194.21.128.0/18194.21.128.1 to 194.21.191.254194.21.191.25516,382
88194.21.192.0/18194.21.192.1 to 194.21.255.254194.21.255.25516,382
89194.22.0.0/18194.22.0.1 to 194.22.63.254194.22.63.25516,382
90194.22.64.0/18194.22.64.1 to 194.22.127.254194.22.127.25516,382
91194.22.128.0/18194.22.128.1 to 194.22.191.254194.22.191.25516,382
92194.22.192.0/18194.22.192.1 to 194.22.255.254194.22.255.25516,382
93194.23.0.0/18194.23.0.1 to 194.23.63.254194.23.63.25516,382
94194.23.64.0/18194.23.64.1 to 194.23.127.254194.23.127.25516,382
95194.23.128.0/18194.23.128.1 to 194.23.191.254194.23.191.25516,382
96194.23.192.0/18194.23.192.1 to 194.23.255.254194.23.255.25516,382
97194.24.0.0/18194.24.0.1 to 194.24.63.254194.24.63.25516,382
98194.24.64.0/18194.24.64.1 to 194.24.127.254194.24.127.25516,382
99194.24.128.0/18194.24.128.1 to 194.24.191.254194.24.191.25516,382
100194.24.192.0/18194.24.192.1 to 194.24.255.254194.24.255.25516,382
101194.25.0.0/18194.25.0.1 to 194.25.63.254194.25.63.25516,382
102194.25.64.0/18194.25.64.1 to 194.25.127.254194.25.127.25516,382
103194.25.128.0/18194.25.128.1 to 194.25.191.254194.25.191.25516,382
104194.25.192.0/18194.25.192.1 to 194.25.255.254194.25.255.25516,382
105194.26.0.0/18194.26.0.1 to 194.26.63.254194.26.63.25516,382
106194.26.64.0/18194.26.64.1 to 194.26.127.254194.26.127.25516,382
107194.26.128.0/18194.26.128.1 to 194.26.191.254194.26.191.25516,382
108194.26.192.0/18194.26.192.1 to 194.26.255.254194.26.255.25516,382
109194.27.0.0/18194.27.0.1 to 194.27.63.254194.27.63.25516,382
110194.27.64.0/18194.27.64.1 to 194.27.127.254194.27.127.25516,382
111194.27.128.0/18194.27.128.1 to 194.27.191.254194.27.191.25516,382
112194.27.192.0/18194.27.192.1 to 194.27.255.254194.27.255.25516,382
113194.28.0.0/18194.28.0.1 to 194.28.63.254194.28.63.25516,382
114194.28.64.0/18194.28.64.1 to 194.28.127.254194.28.127.25516,382
115194.28.128.0/18194.28.128.1 to 194.28.191.254194.28.191.25516,382
116194.28.192.0/18194.28.192.1 to 194.28.255.254194.28.255.25516,382
117194.29.0.0/18194.29.0.1 to 194.29.63.254194.29.63.25516,382
118194.29.64.0/18194.29.64.1 to 194.29.127.254194.29.127.25516,382
119194.29.128.0/18194.29.128.1 to 194.29.191.254194.29.191.25516,382
120194.29.192.0/18194.29.192.1 to 194.29.255.254194.29.255.25516,382
121194.30.0.0/18194.30.0.1 to 194.30.63.254194.30.63.25516,382
122194.30.64.0/18194.30.64.1 to 194.30.127.254194.30.127.25516,382
123194.30.128.0/18194.30.128.1 to 194.30.191.254194.30.191.25516,382
124194.30.192.0/18194.30.192.1 to 194.30.255.254194.30.255.25516,382
125194.31.0.0/18194.31.0.1 to 194.31.63.254194.31.63.25516,382
126194.31.64.0/18194.31.64.1 to 194.31.127.254194.31.127.25516,382
127194.31.128.0/18194.31.128.1 to 194.31.191.254194.31.191.25516,382
128194.31.192.0/18194.31.192.1 to 194.31.255.254194.31.255.25516,382
129194.32.0.0/18194.32.0.1 to 194.32.63.254194.32.63.25516,382
130194.32.64.0/18194.32.64.1 to 194.32.127.254194.32.127.25516,382
131194.32.128.0/18194.32.128.1 to 194.32.191.254194.32.191.25516,382
132194.32.192.0/18194.32.192.1 to 194.32.255.254194.32.255.25516,382
133194.33.0.0/18194.33.0.1 to 194.33.63.254194.33.63.25516,382
134194.33.64.0/18194.33.64.1 to 194.33.127.254194.33.127.25516,382
135194.33.128.0/18194.33.128.1 to 194.33.191.254194.33.191.25516,382
136194.33.192.0/18194.33.192.1 to 194.33.255.254194.33.255.25516,382
137194.34.0.0/18194.34.0.1 to 194.34.63.254194.34.63.25516,382
138194.34.64.0/18194.34.64.1 to 194.34.127.254194.34.127.25516,382
139194.34.128.0/18194.34.128.1 to 194.34.191.254194.34.191.25516,382
140194.34.192.0/18194.34.192.1 to 194.34.255.254194.34.255.25516,382
141194.35.0.0/18194.35.0.1 to 194.35.63.254194.35.63.25516,382
142194.35.64.0/18194.35.64.1 to 194.35.127.254194.35.127.25516,382
143194.35.128.0/18194.35.128.1 to 194.35.191.254194.35.191.25516,382
144194.35.192.0/18194.35.192.1 to 194.35.255.254194.35.255.25516,382
145194.36.0.0/18194.36.0.1 to 194.36.63.254194.36.63.25516,382
146194.36.64.0/18194.36.64.1 to 194.36.127.254194.36.127.25516,382
147194.36.128.0/18194.36.128.1 to 194.36.191.254194.36.191.25516,382
148194.36.192.0/18194.36.192.1 to 194.36.255.254194.36.255.25516,382
149194.37.0.0/18194.37.0.1 to 194.37.63.254194.37.63.25516,382
150194.37.64.0/18194.37.64.1 to 194.37.127.254194.37.127.25516,382
151194.37.128.0/18194.37.128.1 to 194.37.191.254194.37.191.25516,382
152194.37.192.0/18194.37.192.1 to 194.37.255.254194.37.255.25516,382
153194.38.0.0/18194.38.0.1 to 194.38.63.254194.38.63.25516,382
154194.38.64.0/18194.38.64.1 to 194.38.127.254194.38.127.25516,382
155194.38.128.0/18194.38.128.1 to 194.38.191.254194.38.191.25516,382
156194.38.192.0/18194.38.192.1 to 194.38.255.254194.38.255.25516,382
157194.39.0.0/18194.39.0.1 to 194.39.63.254194.39.63.25516,382
158194.39.64.0/18194.39.64.1 to 194.39.127.254194.39.127.25516,382
159194.39.128.0/18194.39.128.1 to 194.39.191.254194.39.191.25516,382
160194.39.192.0/18194.39.192.1 to 194.39.255.254194.39.255.25516,382
161194.40.0.0/18194.40.0.1 to 194.40.63.254194.40.63.25516,382
162194.40.64.0/18194.40.64.1 to 194.40.127.254194.40.127.25516,382
163194.40.128.0/18194.40.128.1 to 194.40.191.254194.40.191.25516,382
164194.40.192.0/18194.40.192.1 to 194.40.255.254194.40.255.25516,382
165194.41.0.0/18194.41.0.1 to 194.41.63.254194.41.63.25516,382
166194.41.64.0/18194.41.64.1 to 194.41.127.254194.41.127.25516,382
167194.41.128.0/18194.41.128.1 to 194.41.191.254194.41.191.25516,382
168194.41.192.0/18194.41.192.1 to 194.41.255.254194.41.255.25516,382
169194.42.0.0/18194.42.0.1 to 194.42.63.254194.42.63.25516,382
170194.42.64.0/18194.42.64.1 to 194.42.127.254194.42.127.25516,382
171194.42.128.0/18194.42.128.1 to 194.42.191.254194.42.191.25516,382
172194.42.192.0/18194.42.192.1 to 194.42.255.254194.42.255.25516,382
173194.43.0.0/18194.43.0.1 to 194.43.63.254194.43.63.25516,382
174194.43.64.0/18194.43.64.1 to 194.43.127.254194.43.127.25516,382
175194.43.128.0/18194.43.128.1 to 194.43.191.254194.43.191.25516,382
176194.43.192.0/18194.43.192.1 to 194.43.255.254194.43.255.25516,382
177194.44.0.0/18194.44.0.1 to 194.44.63.254194.44.63.25516,382
178194.44.64.0/18194.44.64.1 to 194.44.127.254194.44.127.25516,382
179194.44.128.0/18194.44.128.1 to 194.44.191.254194.44.191.25516,382
180194.44.192.0/18194.44.192.1 to 194.44.255.254194.44.255.25516,382
181194.45.0.0/18194.45.0.1 to 194.45.63.254194.45.63.25516,382
182194.45.64.0/18194.45.64.1 to 194.45.127.254194.45.127.25516,382
183194.45.128.0/18194.45.128.1 to 194.45.191.254194.45.191.25516,382
184194.45.192.0/18194.45.192.1 to 194.45.255.254194.45.255.25516,382
185194.46.0.0/18194.46.0.1 to 194.46.63.254194.46.63.25516,382
186194.46.64.0/18194.46.64.1 to 194.46.127.254194.46.127.25516,382
187194.46.128.0/18194.46.128.1 to 194.46.191.254194.46.191.25516,382
188194.46.192.0/18194.46.192.1 to 194.46.255.254194.46.255.25516,382
189194.47.0.0/18194.47.0.1 to 194.47.63.254194.47.63.25516,382
190194.47.64.0/18194.47.64.1 to 194.47.127.254194.47.127.25516,382
191194.47.128.0/18194.47.128.1 to 194.47.191.254194.47.191.25516,382
192194.47.192.0/18194.47.192.1 to 194.47.255.254194.47.255.25516,382
193194.48.0.0/18194.48.0.1 to 194.48.63.254194.48.63.25516,382
194194.48.64.0/18194.48.64.1 to 194.48.127.254194.48.127.25516,382
195194.48.128.0/18194.48.128.1 to 194.48.191.254194.48.191.25516,382
196194.48.192.0/18194.48.192.1 to 194.48.255.254194.48.255.25516,382
197194.49.0.0/18194.49.0.1 to 194.49.63.254194.49.63.25516,382
198194.49.64.0/18194.49.64.1 to 194.49.127.254194.49.127.25516,382
199194.49.128.0/18194.49.128.1 to 194.49.191.254194.49.191.25516,382
200194.49.192.0/18194.49.192.1 to 194.49.255.254194.49.255.25516,382
201194.50.0.0/18194.50.0.1 to 194.50.63.254194.50.63.25516,382
202194.50.64.0/18194.50.64.1 to 194.50.127.254194.50.127.25516,382
203194.50.128.0/18194.50.128.1 to 194.50.191.254194.50.191.25516,382
204194.50.192.0/18194.50.192.1 to 194.50.255.254194.50.255.25516,382
205194.51.0.0/18194.51.0.1 to 194.51.63.254194.51.63.25516,382
206194.51.64.0/18194.51.64.1 to 194.51.127.254194.51.127.25516,382
207194.51.128.0/18194.51.128.1 to 194.51.191.254194.51.191.25516,382
208194.51.192.0/18194.51.192.1 to 194.51.255.254194.51.255.25516,382
209194.52.0.0/18194.52.0.1 to 194.52.63.254194.52.63.25516,382
210194.52.64.0/18194.52.64.1 to 194.52.127.254194.52.127.25516,382
211194.52.128.0/18194.52.128.1 to 194.52.191.254194.52.191.25516,382
212194.52.192.0/18194.52.192.1 to 194.52.255.254194.52.255.25516,382
213194.53.0.0/18194.53.0.1 to 194.53.63.254194.53.63.25516,382
214194.53.64.0/18194.53.64.1 to 194.53.127.254194.53.127.25516,382
215194.53.128.0/18194.53.128.1 to 194.53.191.254194.53.191.25516,382
216194.53.192.0/18194.53.192.1 to 194.53.255.254194.53.255.25516,382
217194.54.0.0/18194.54.0.1 to 194.54.63.254194.54.63.25516,382
218194.54.64.0/18194.54.64.1 to 194.54.127.254194.54.127.25516,382
219194.54.128.0/18194.54.128.1 to 194.54.191.254194.54.191.25516,382
220194.54.192.0/18194.54.192.1 to 194.54.255.254194.54.255.25516,382
221194.55.0.0/18194.55.0.1 to 194.55.63.254194.55.63.25516,382
222194.55.64.0/18194.55.64.1 to 194.55.127.254194.55.127.25516,382
223194.55.128.0/18194.55.128.1 to 194.55.191.254194.55.191.25516,382
224194.55.192.0/18194.55.192.1 to 194.55.255.254194.55.255.25516,382
225194.56.0.0/18194.56.0.1 to 194.56.63.254194.56.63.25516,382
226194.56.64.0/18194.56.64.1 to 194.56.127.254194.56.127.25516,382
227194.56.128.0/18194.56.128.1 to 194.56.191.254194.56.191.25516,382
228194.56.192.0/18194.56.192.1 to 194.56.255.254194.56.255.25516,382
229194.57.0.0/18194.57.0.1 to 194.57.63.254194.57.63.25516,382
230194.57.64.0/18194.57.64.1 to 194.57.127.254194.57.127.25516,382
231194.57.128.0/18194.57.128.1 to 194.57.191.254194.57.191.25516,382
232194.57.192.0/18194.57.192.1 to 194.57.255.254194.57.255.25516,382
233194.58.0.0/18194.58.0.1 to 194.58.63.254194.58.63.25516,382
234194.58.64.0/18194.58.64.1 to 194.58.127.254194.58.127.25516,382
235194.58.128.0/18194.58.128.1 to 194.58.191.254194.58.191.25516,382
236194.58.192.0/18194.58.192.1 to 194.58.255.254194.58.255.25516,382
237194.59.0.0/18194.59.0.1 to 194.59.63.254194.59.63.25516,382
238194.59.64.0/18194.59.64.1 to 194.59.127.254194.59.127.25516,382
239194.59.128.0/18194.59.128.1 to 194.59.191.254194.59.191.25516,382
240194.59.192.0/18194.59.192.1 to 194.59.255.254194.59.255.25516,382
241194.60.0.0/18194.60.0.1 to 194.60.63.254194.60.63.25516,382
242194.60.64.0/18194.60.64.1 to 194.60.127.254194.60.127.25516,382
243194.60.128.0/18194.60.128.1 to 194.60.191.254194.60.191.25516,382
244194.60.192.0/18194.60.192.1 to 194.60.255.254194.60.255.25516,382
245194.61.0.0/18194.61.0.1 to 194.61.63.254194.61.63.25516,382
246194.61.64.0/18194.61.64.1 to 194.61.127.254194.61.127.25516,382
247194.61.128.0/18194.61.128.1 to 194.61.191.254194.61.191.25516,382
248194.61.192.0/18194.61.192.1 to 194.61.255.254194.61.255.25516,382
249194.62.0.0/18194.62.0.1 to 194.62.63.254194.62.63.25516,382
250194.62.64.0/18194.62.64.1 to 194.62.127.254194.62.127.25516,382
251194.62.128.0/18194.62.128.1 to 194.62.191.254194.62.191.25516,382
252194.62.192.0/18194.62.192.1 to 194.62.255.254194.62.255.25516,382
253194.63.0.0/18194.63.0.1 to 194.63.63.254194.63.63.25516,382
254194.63.64.0/18194.63.64.1 to 194.63.127.254194.63.127.25516,382
255194.63.128.0/18194.63.128.1 to 194.63.191.254194.63.191.25516,382
256194.63.192.0/18194.63.192.1 to 194.63.255.254194.63.255.25516,382

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.