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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.

Network211.136.0.0/14
Usable hosts262,142
Subnet mask255.252.0.0
Addresses262,144
Network address
211.136.0.0
Broadcast address
211.139.255.255
First usable
211.136.0.1
Last usable
211.139.255.254
Usable hosts
262,142 (262,144 less the network and broadcast addresses)
Subnet mask
255.252.0.0
Wildcard mask
0.3.255.255 (Cisco ACLs, OSPF)
Prefix length
/14
Type
Public public
Old class
C (default /24)
As numbers
Hex D3880000 · Integer 3548905472 to 3549167615
Reverse DNS zones
136.211.in-addr.arpa
137.211.in-addr.arpa
138.211.in-addr.arpa
139.211.in-addr.arpa
/14 is not on a 8-bit boundary, so it takes 4 /16 zones.
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address11010011.10001000.00000000.00000000211.136.0.0
Subnet mask11111111.11111100.00000000.00000000255.252.0.0
Network11010011.10001000.00000000.00000000211.136.0.0
Broadcast11010011.10001011.11111111.11111111211.139.255.255
Split into smaller subnets/26
/15 (2)/16 (4)/17 (8)/18 (16)/19 (32)/20 (64)/21 (128)/22 (256)/23 (512)/24 (1,024)/25 (2,048)/26 (4,096)

211.136.0.0/14 makes 4,096 subnets of /26; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
1211.136.0.0/26211.136.0.1 to 211.136.0.62211.136.0.6362
2211.136.0.64/26211.136.0.65 to 211.136.0.126211.136.0.12762
3211.136.0.128/26211.136.0.129 to 211.136.0.190211.136.0.19162
4211.136.0.192/26211.136.0.193 to 211.136.0.254211.136.0.25562
5211.136.1.0/26211.136.1.1 to 211.136.1.62211.136.1.6362
6211.136.1.64/26211.136.1.65 to 211.136.1.126211.136.1.12762
7211.136.1.128/26211.136.1.129 to 211.136.1.190211.136.1.19162
8211.136.1.192/26211.136.1.193 to 211.136.1.254211.136.1.25562
9211.136.2.0/26211.136.2.1 to 211.136.2.62211.136.2.6362
10211.136.2.64/26211.136.2.65 to 211.136.2.126211.136.2.12762
11211.136.2.128/26211.136.2.129 to 211.136.2.190211.136.2.19162
12211.136.2.192/26211.136.2.193 to 211.136.2.254211.136.2.25562
13211.136.3.0/26211.136.3.1 to 211.136.3.62211.136.3.6362
14211.136.3.64/26211.136.3.65 to 211.136.3.126211.136.3.12762
15211.136.3.128/26211.136.3.129 to 211.136.3.190211.136.3.19162
16211.136.3.192/26211.136.3.193 to 211.136.3.254211.136.3.25562
17211.136.4.0/26211.136.4.1 to 211.136.4.62211.136.4.6362
18211.136.4.64/26211.136.4.65 to 211.136.4.126211.136.4.12762
19211.136.4.128/26211.136.4.129 to 211.136.4.190211.136.4.19162
20211.136.4.192/26211.136.4.193 to 211.136.4.254211.136.4.25562
21211.136.5.0/26211.136.5.1 to 211.136.5.62211.136.5.6362
22211.136.5.64/26211.136.5.65 to 211.136.5.126211.136.5.12762
23211.136.5.128/26211.136.5.129 to 211.136.5.190211.136.5.19162
24211.136.5.192/26211.136.5.193 to 211.136.5.254211.136.5.25562
25211.136.6.0/26211.136.6.1 to 211.136.6.62211.136.6.6362
26211.136.6.64/26211.136.6.65 to 211.136.6.126211.136.6.12762
27211.136.6.128/26211.136.6.129 to 211.136.6.190211.136.6.19162
28211.136.6.192/26211.136.6.193 to 211.136.6.254211.136.6.25562
29211.136.7.0/26211.136.7.1 to 211.136.7.62211.136.7.6362
30211.136.7.64/26211.136.7.65 to 211.136.7.126211.136.7.12762
31211.136.7.128/26211.136.7.129 to 211.136.7.190211.136.7.19162
32211.136.7.192/26211.136.7.193 to 211.136.7.254211.136.7.25562
33211.136.8.0/26211.136.8.1 to 211.136.8.62211.136.8.6362
34211.136.8.64/26211.136.8.65 to 211.136.8.126211.136.8.12762
35211.136.8.128/26211.136.8.129 to 211.136.8.190211.136.8.19162
36211.136.8.192/26211.136.8.193 to 211.136.8.254211.136.8.25562
37211.136.9.0/26211.136.9.1 to 211.136.9.62211.136.9.6362
38211.136.9.64/26211.136.9.65 to 211.136.9.126211.136.9.12762
39211.136.9.128/26211.136.9.129 to 211.136.9.190211.136.9.19162
40211.136.9.192/26211.136.9.193 to 211.136.9.254211.136.9.25562
41211.136.10.0/26211.136.10.1 to 211.136.10.62211.136.10.6362
42211.136.10.64/26211.136.10.65 to 211.136.10.126211.136.10.12762
43211.136.10.128/26211.136.10.129 to 211.136.10.190211.136.10.19162
44211.136.10.192/26211.136.10.193 to 211.136.10.254211.136.10.25562
45211.136.11.0/26211.136.11.1 to 211.136.11.62211.136.11.6362
46211.136.11.64/26211.136.11.65 to 211.136.11.126211.136.11.12762
47211.136.11.128/26211.136.11.129 to 211.136.11.190211.136.11.19162
48211.136.11.192/26211.136.11.193 to 211.136.11.254211.136.11.25562
49211.136.12.0/26211.136.12.1 to 211.136.12.62211.136.12.6362
50211.136.12.64/26211.136.12.65 to 211.136.12.126211.136.12.12762
51211.136.12.128/26211.136.12.129 to 211.136.12.190211.136.12.19162
52211.136.12.192/26211.136.12.193 to 211.136.12.254211.136.12.25562
53211.136.13.0/26211.136.13.1 to 211.136.13.62211.136.13.6362
54211.136.13.64/26211.136.13.65 to 211.136.13.126211.136.13.12762
55211.136.13.128/26211.136.13.129 to 211.136.13.190211.136.13.19162
56211.136.13.192/26211.136.13.193 to 211.136.13.254211.136.13.25562
57211.136.14.0/26211.136.14.1 to 211.136.14.62211.136.14.6362
58211.136.14.64/26211.136.14.65 to 211.136.14.126211.136.14.12762
59211.136.14.128/26211.136.14.129 to 211.136.14.190211.136.14.19162
60211.136.14.192/26211.136.14.193 to 211.136.14.254211.136.14.25562
61211.136.15.0/26211.136.15.1 to 211.136.15.62211.136.15.6362
62211.136.15.64/26211.136.15.65 to 211.136.15.126211.136.15.12762
63211.136.15.128/26211.136.15.129 to 211.136.15.190211.136.15.19162
64211.136.15.192/26211.136.15.193 to 211.136.15.254211.136.15.25562
65211.136.16.0/26211.136.16.1 to 211.136.16.62211.136.16.6362
66211.136.16.64/26211.136.16.65 to 211.136.16.126211.136.16.12762
67211.136.16.128/26211.136.16.129 to 211.136.16.190211.136.16.19162
68211.136.16.192/26211.136.16.193 to 211.136.16.254211.136.16.25562
69211.136.17.0/26211.136.17.1 to 211.136.17.62211.136.17.6362
70211.136.17.64/26211.136.17.65 to 211.136.17.126211.136.17.12762
71211.136.17.128/26211.136.17.129 to 211.136.17.190211.136.17.19162
72211.136.17.192/26211.136.17.193 to 211.136.17.254211.136.17.25562
73211.136.18.0/26211.136.18.1 to 211.136.18.62211.136.18.6362
74211.136.18.64/26211.136.18.65 to 211.136.18.126211.136.18.12762
75211.136.18.128/26211.136.18.129 to 211.136.18.190211.136.18.19162
76211.136.18.192/26211.136.18.193 to 211.136.18.254211.136.18.25562
77211.136.19.0/26211.136.19.1 to 211.136.19.62211.136.19.6362
78211.136.19.64/26211.136.19.65 to 211.136.19.126211.136.19.12762
79211.136.19.128/26211.136.19.129 to 211.136.19.190211.136.19.19162
80211.136.19.192/26211.136.19.193 to 211.136.19.254211.136.19.25562
81211.136.20.0/26211.136.20.1 to 211.136.20.62211.136.20.6362
82211.136.20.64/26211.136.20.65 to 211.136.20.126211.136.20.12762
83211.136.20.128/26211.136.20.129 to 211.136.20.190211.136.20.19162
84211.136.20.192/26211.136.20.193 to 211.136.20.254211.136.20.25562
85211.136.21.0/26211.136.21.1 to 211.136.21.62211.136.21.6362
86211.136.21.64/26211.136.21.65 to 211.136.21.126211.136.21.12762
87211.136.21.128/26211.136.21.129 to 211.136.21.190211.136.21.19162
88211.136.21.192/26211.136.21.193 to 211.136.21.254211.136.21.25562
89211.136.22.0/26211.136.22.1 to 211.136.22.62211.136.22.6362
90211.136.22.64/26211.136.22.65 to 211.136.22.126211.136.22.12762
91211.136.22.128/26211.136.22.129 to 211.136.22.190211.136.22.19162
92211.136.22.192/26211.136.22.193 to 211.136.22.254211.136.22.25562
93211.136.23.0/26211.136.23.1 to 211.136.23.62211.136.23.6362
94211.136.23.64/26211.136.23.65 to 211.136.23.126211.136.23.12762
95211.136.23.128/26211.136.23.129 to 211.136.23.190211.136.23.19162
96211.136.23.192/26211.136.23.193 to 211.136.23.254211.136.23.25562
97211.136.24.0/26211.136.24.1 to 211.136.24.62211.136.24.6362
98211.136.24.64/26211.136.24.65 to 211.136.24.126211.136.24.12762
99211.136.24.128/26211.136.24.129 to 211.136.24.190211.136.24.19162
100211.136.24.192/26211.136.24.193 to 211.136.24.254211.136.24.25562
101211.136.25.0/26211.136.25.1 to 211.136.25.62211.136.25.6362
102211.136.25.64/26211.136.25.65 to 211.136.25.126211.136.25.12762
103211.136.25.128/26211.136.25.129 to 211.136.25.190211.136.25.19162
104211.136.25.192/26211.136.25.193 to 211.136.25.254211.136.25.25562
105211.136.26.0/26211.136.26.1 to 211.136.26.62211.136.26.6362
106211.136.26.64/26211.136.26.65 to 211.136.26.126211.136.26.12762
107211.136.26.128/26211.136.26.129 to 211.136.26.190211.136.26.19162
108211.136.26.192/26211.136.26.193 to 211.136.26.254211.136.26.25562
109211.136.27.0/26211.136.27.1 to 211.136.27.62211.136.27.6362
110211.136.27.64/26211.136.27.65 to 211.136.27.126211.136.27.12762
111211.136.27.128/26211.136.27.129 to 211.136.27.190211.136.27.19162
112211.136.27.192/26211.136.27.193 to 211.136.27.254211.136.27.25562
113211.136.28.0/26211.136.28.1 to 211.136.28.62211.136.28.6362
114211.136.28.64/26211.136.28.65 to 211.136.28.126211.136.28.12762
115211.136.28.128/26211.136.28.129 to 211.136.28.190211.136.28.19162
116211.136.28.192/26211.136.28.193 to 211.136.28.254211.136.28.25562
117211.136.29.0/26211.136.29.1 to 211.136.29.62211.136.29.6362
118211.136.29.64/26211.136.29.65 to 211.136.29.126211.136.29.12762
119211.136.29.128/26211.136.29.129 to 211.136.29.190211.136.29.19162
120211.136.29.192/26211.136.29.193 to 211.136.29.254211.136.29.25562
121211.136.30.0/26211.136.30.1 to 211.136.30.62211.136.30.6362
122211.136.30.64/26211.136.30.65 to 211.136.30.126211.136.30.12762
123211.136.30.128/26211.136.30.129 to 211.136.30.190211.136.30.19162
124211.136.30.192/26211.136.30.193 to 211.136.30.254211.136.30.25562
125211.136.31.0/26211.136.31.1 to 211.136.31.62211.136.31.6362
126211.136.31.64/26211.136.31.65 to 211.136.31.126211.136.31.12762
127211.136.31.128/26211.136.31.129 to 211.136.31.190211.136.31.19162
128211.136.31.192/26211.136.31.193 to 211.136.31.254211.136.31.25562
129211.136.32.0/26211.136.32.1 to 211.136.32.62211.136.32.6362
130211.136.32.64/26211.136.32.65 to 211.136.32.126211.136.32.12762
131211.136.32.128/26211.136.32.129 to 211.136.32.190211.136.32.19162
132211.136.32.192/26211.136.32.193 to 211.136.32.254211.136.32.25562
133211.136.33.0/26211.136.33.1 to 211.136.33.62211.136.33.6362
134211.136.33.64/26211.136.33.65 to 211.136.33.126211.136.33.12762
135211.136.33.128/26211.136.33.129 to 211.136.33.190211.136.33.19162
136211.136.33.192/26211.136.33.193 to 211.136.33.254211.136.33.25562
137211.136.34.0/26211.136.34.1 to 211.136.34.62211.136.34.6362
138211.136.34.64/26211.136.34.65 to 211.136.34.126211.136.34.12762
139211.136.34.128/26211.136.34.129 to 211.136.34.190211.136.34.19162
140211.136.34.192/26211.136.34.193 to 211.136.34.254211.136.34.25562
141211.136.35.0/26211.136.35.1 to 211.136.35.62211.136.35.6362
142211.136.35.64/26211.136.35.65 to 211.136.35.126211.136.35.12762
143211.136.35.128/26211.136.35.129 to 211.136.35.190211.136.35.19162
144211.136.35.192/26211.136.35.193 to 211.136.35.254211.136.35.25562
145211.136.36.0/26211.136.36.1 to 211.136.36.62211.136.36.6362
146211.136.36.64/26211.136.36.65 to 211.136.36.126211.136.36.12762
147211.136.36.128/26211.136.36.129 to 211.136.36.190211.136.36.19162
148211.136.36.192/26211.136.36.193 to 211.136.36.254211.136.36.25562
149211.136.37.0/26211.136.37.1 to 211.136.37.62211.136.37.6362
150211.136.37.64/26211.136.37.65 to 211.136.37.126211.136.37.12762
151211.136.37.128/26211.136.37.129 to 211.136.37.190211.136.37.19162
152211.136.37.192/26211.136.37.193 to 211.136.37.254211.136.37.25562
153211.136.38.0/26211.136.38.1 to 211.136.38.62211.136.38.6362
154211.136.38.64/26211.136.38.65 to 211.136.38.126211.136.38.12762
155211.136.38.128/26211.136.38.129 to 211.136.38.190211.136.38.19162
156211.136.38.192/26211.136.38.193 to 211.136.38.254211.136.38.25562
157211.136.39.0/26211.136.39.1 to 211.136.39.62211.136.39.6362
158211.136.39.64/26211.136.39.65 to 211.136.39.126211.136.39.12762
159211.136.39.128/26211.136.39.129 to 211.136.39.190211.136.39.19162
160211.136.39.192/26211.136.39.193 to 211.136.39.254211.136.39.25562
161211.136.40.0/26211.136.40.1 to 211.136.40.62211.136.40.6362
162211.136.40.64/26211.136.40.65 to 211.136.40.126211.136.40.12762
163211.136.40.128/26211.136.40.129 to 211.136.40.190211.136.40.19162
164211.136.40.192/26211.136.40.193 to 211.136.40.254211.136.40.25562
165211.136.41.0/26211.136.41.1 to 211.136.41.62211.136.41.6362
166211.136.41.64/26211.136.41.65 to 211.136.41.126211.136.41.12762
167211.136.41.128/26211.136.41.129 to 211.136.41.190211.136.41.19162
168211.136.41.192/26211.136.41.193 to 211.136.41.254211.136.41.25562
169211.136.42.0/26211.136.42.1 to 211.136.42.62211.136.42.6362
170211.136.42.64/26211.136.42.65 to 211.136.42.126211.136.42.12762
171211.136.42.128/26211.136.42.129 to 211.136.42.190211.136.42.19162
172211.136.42.192/26211.136.42.193 to 211.136.42.254211.136.42.25562
173211.136.43.0/26211.136.43.1 to 211.136.43.62211.136.43.6362
174211.136.43.64/26211.136.43.65 to 211.136.43.126211.136.43.12762
175211.136.43.128/26211.136.43.129 to 211.136.43.190211.136.43.19162
176211.136.43.192/26211.136.43.193 to 211.136.43.254211.136.43.25562
177211.136.44.0/26211.136.44.1 to 211.136.44.62211.136.44.6362
178211.136.44.64/26211.136.44.65 to 211.136.44.126211.136.44.12762
179211.136.44.128/26211.136.44.129 to 211.136.44.190211.136.44.19162
180211.136.44.192/26211.136.44.193 to 211.136.44.254211.136.44.25562
181211.136.45.0/26211.136.45.1 to 211.136.45.62211.136.45.6362
182211.136.45.64/26211.136.45.65 to 211.136.45.126211.136.45.12762
183211.136.45.128/26211.136.45.129 to 211.136.45.190211.136.45.19162
184211.136.45.192/26211.136.45.193 to 211.136.45.254211.136.45.25562
185211.136.46.0/26211.136.46.1 to 211.136.46.62211.136.46.6362
186211.136.46.64/26211.136.46.65 to 211.136.46.126211.136.46.12762
187211.136.46.128/26211.136.46.129 to 211.136.46.190211.136.46.19162
188211.136.46.192/26211.136.46.193 to 211.136.46.254211.136.46.25562
189211.136.47.0/26211.136.47.1 to 211.136.47.62211.136.47.6362
190211.136.47.64/26211.136.47.65 to 211.136.47.126211.136.47.12762
191211.136.47.128/26211.136.47.129 to 211.136.47.190211.136.47.19162
192211.136.47.192/26211.136.47.193 to 211.136.47.254211.136.47.25562
193211.136.48.0/26211.136.48.1 to 211.136.48.62211.136.48.6362
194211.136.48.64/26211.136.48.65 to 211.136.48.126211.136.48.12762
195211.136.48.128/26211.136.48.129 to 211.136.48.190211.136.48.19162
196211.136.48.192/26211.136.48.193 to 211.136.48.254211.136.48.25562
197211.136.49.0/26211.136.49.1 to 211.136.49.62211.136.49.6362
198211.136.49.64/26211.136.49.65 to 211.136.49.126211.136.49.12762
199211.136.49.128/26211.136.49.129 to 211.136.49.190211.136.49.19162
200211.136.49.192/26211.136.49.193 to 211.136.49.254211.136.49.25562
201211.136.50.0/26211.136.50.1 to 211.136.50.62211.136.50.6362
202211.136.50.64/26211.136.50.65 to 211.136.50.126211.136.50.12762
203211.136.50.128/26211.136.50.129 to 211.136.50.190211.136.50.19162
204211.136.50.192/26211.136.50.193 to 211.136.50.254211.136.50.25562
205211.136.51.0/26211.136.51.1 to 211.136.51.62211.136.51.6362
206211.136.51.64/26211.136.51.65 to 211.136.51.126211.136.51.12762
207211.136.51.128/26211.136.51.129 to 211.136.51.190211.136.51.19162
208211.136.51.192/26211.136.51.193 to 211.136.51.254211.136.51.25562
209211.136.52.0/26211.136.52.1 to 211.136.52.62211.136.52.6362
210211.136.52.64/26211.136.52.65 to 211.136.52.126211.136.52.12762
211211.136.52.128/26211.136.52.129 to 211.136.52.190211.136.52.19162
212211.136.52.192/26211.136.52.193 to 211.136.52.254211.136.52.25562
213211.136.53.0/26211.136.53.1 to 211.136.53.62211.136.53.6362
214211.136.53.64/26211.136.53.65 to 211.136.53.126211.136.53.12762
215211.136.53.128/26211.136.53.129 to 211.136.53.190211.136.53.19162
216211.136.53.192/26211.136.53.193 to 211.136.53.254211.136.53.25562
217211.136.54.0/26211.136.54.1 to 211.136.54.62211.136.54.6362
218211.136.54.64/26211.136.54.65 to 211.136.54.126211.136.54.12762
219211.136.54.128/26211.136.54.129 to 211.136.54.190211.136.54.19162
220211.136.54.192/26211.136.54.193 to 211.136.54.254211.136.54.25562
221211.136.55.0/26211.136.55.1 to 211.136.55.62211.136.55.6362
222211.136.55.64/26211.136.55.65 to 211.136.55.126211.136.55.12762
223211.136.55.128/26211.136.55.129 to 211.136.55.190211.136.55.19162
224211.136.55.192/26211.136.55.193 to 211.136.55.254211.136.55.25562
225211.136.56.0/26211.136.56.1 to 211.136.56.62211.136.56.6362
226211.136.56.64/26211.136.56.65 to 211.136.56.126211.136.56.12762
227211.136.56.128/26211.136.56.129 to 211.136.56.190211.136.56.19162
228211.136.56.192/26211.136.56.193 to 211.136.56.254211.136.56.25562
229211.136.57.0/26211.136.57.1 to 211.136.57.62211.136.57.6362
230211.136.57.64/26211.136.57.65 to 211.136.57.126211.136.57.12762
231211.136.57.128/26211.136.57.129 to 211.136.57.190211.136.57.19162
232211.136.57.192/26211.136.57.193 to 211.136.57.254211.136.57.25562
233211.136.58.0/26211.136.58.1 to 211.136.58.62211.136.58.6362
234211.136.58.64/26211.136.58.65 to 211.136.58.126211.136.58.12762
235211.136.58.128/26211.136.58.129 to 211.136.58.190211.136.58.19162
236211.136.58.192/26211.136.58.193 to 211.136.58.254211.136.58.25562
237211.136.59.0/26211.136.59.1 to 211.136.59.62211.136.59.6362
238211.136.59.64/26211.136.59.65 to 211.136.59.126211.136.59.12762
239211.136.59.128/26211.136.59.129 to 211.136.59.190211.136.59.19162
240211.136.59.192/26211.136.59.193 to 211.136.59.254211.136.59.25562
241211.136.60.0/26211.136.60.1 to 211.136.60.62211.136.60.6362
242211.136.60.64/26211.136.60.65 to 211.136.60.126211.136.60.12762
243211.136.60.128/26211.136.60.129 to 211.136.60.190211.136.60.19162
244211.136.60.192/26211.136.60.193 to 211.136.60.254211.136.60.25562
245211.136.61.0/26211.136.61.1 to 211.136.61.62211.136.61.6362
246211.136.61.64/26211.136.61.65 to 211.136.61.126211.136.61.12762
247211.136.61.128/26211.136.61.129 to 211.136.61.190211.136.61.19162
248211.136.61.192/26211.136.61.193 to 211.136.61.254211.136.61.25562
249211.136.62.0/26211.136.62.1 to 211.136.62.62211.136.62.6362
250211.136.62.64/26211.136.62.65 to 211.136.62.126211.136.62.12762
251211.136.62.128/26211.136.62.129 to 211.136.62.190211.136.62.19162
252211.136.62.192/26211.136.62.193 to 211.136.62.254211.136.62.25562
253211.136.63.0/26211.136.63.1 to 211.136.63.62211.136.63.6362
254211.136.63.64/26211.136.63.65 to 211.136.63.126211.136.63.12762
255211.136.63.128/26211.136.63.129 to 211.136.63.190211.136.63.19162
256211.136.63.192/26211.136.63.193 to 211.136.63.254211.136.63.25562

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.