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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.

Network235.26.0.0/19
Usable hosts8,190
Subnet mask255.255.224.0
Addresses8,192
Network address
235.26.0.0
Broadcast address
235.26.31.255
First usable
235.26.0.1
Last usable
235.26.31.254
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
Multicast 224.0.0.0/4
One-to-many traffic, such as IPTV and routing protocols
Old class
D (multicast)
As numbers
Hex EB1A0000 · Integer 3944349696 to 3944357887
Reverse DNS zones
0.26.235.in-addr.arpa
1.26.235.in-addr.arpa
2.26.235.in-addr.arpa
3.26.235.in-addr.arpa
4.26.235.in-addr.arpa
5.26.235.in-addr.arpa
6.26.235.in-addr.arpa
7.26.235.in-addr.arpa
8.26.235.in-addr.arpa
9.26.235.in-addr.arpa
10.26.235.in-addr.arpa
11.26.235.in-addr.arpa
12.26.235.in-addr.arpa
13.26.235.in-addr.arpa
14.26.235.in-addr.arpa
15.26.235.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
Address11101011.00011010.00000000.00000000235.26.0.0
Subnet mask11111111.11111111.11100000.00000000255.255.224.0
Network11101011.00011010.00000000.00000000235.26.0.0
Broadcast11101011.00011010.00011111.11111111235.26.31.255
Split into smaller subnets/27
/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)

235.26.0.0/19 makes 256 subnets of /27.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
1235.26.0.0/27235.26.0.1 to 235.26.0.30235.26.0.3130
2235.26.0.32/27235.26.0.33 to 235.26.0.62235.26.0.6330
3235.26.0.64/27235.26.0.65 to 235.26.0.94235.26.0.9530
4235.26.0.96/27235.26.0.97 to 235.26.0.126235.26.0.12730
5235.26.0.128/27235.26.0.129 to 235.26.0.158235.26.0.15930
6235.26.0.160/27235.26.0.161 to 235.26.0.190235.26.0.19130
7235.26.0.192/27235.26.0.193 to 235.26.0.222235.26.0.22330
8235.26.0.224/27235.26.0.225 to 235.26.0.254235.26.0.25530
9235.26.1.0/27235.26.1.1 to 235.26.1.30235.26.1.3130
10235.26.1.32/27235.26.1.33 to 235.26.1.62235.26.1.6330
11235.26.1.64/27235.26.1.65 to 235.26.1.94235.26.1.9530
12235.26.1.96/27235.26.1.97 to 235.26.1.126235.26.1.12730
13235.26.1.128/27235.26.1.129 to 235.26.1.158235.26.1.15930
14235.26.1.160/27235.26.1.161 to 235.26.1.190235.26.1.19130
15235.26.1.192/27235.26.1.193 to 235.26.1.222235.26.1.22330
16235.26.1.224/27235.26.1.225 to 235.26.1.254235.26.1.25530
17235.26.2.0/27235.26.2.1 to 235.26.2.30235.26.2.3130
18235.26.2.32/27235.26.2.33 to 235.26.2.62235.26.2.6330
19235.26.2.64/27235.26.2.65 to 235.26.2.94235.26.2.9530
20235.26.2.96/27235.26.2.97 to 235.26.2.126235.26.2.12730
21235.26.2.128/27235.26.2.129 to 235.26.2.158235.26.2.15930
22235.26.2.160/27235.26.2.161 to 235.26.2.190235.26.2.19130
23235.26.2.192/27235.26.2.193 to 235.26.2.222235.26.2.22330
24235.26.2.224/27235.26.2.225 to 235.26.2.254235.26.2.25530
25235.26.3.0/27235.26.3.1 to 235.26.3.30235.26.3.3130
26235.26.3.32/27235.26.3.33 to 235.26.3.62235.26.3.6330
27235.26.3.64/27235.26.3.65 to 235.26.3.94235.26.3.9530
28235.26.3.96/27235.26.3.97 to 235.26.3.126235.26.3.12730
29235.26.3.128/27235.26.3.129 to 235.26.3.158235.26.3.15930
30235.26.3.160/27235.26.3.161 to 235.26.3.190235.26.3.19130
31235.26.3.192/27235.26.3.193 to 235.26.3.222235.26.3.22330
32235.26.3.224/27235.26.3.225 to 235.26.3.254235.26.3.25530
33235.26.4.0/27235.26.4.1 to 235.26.4.30235.26.4.3130
34235.26.4.32/27235.26.4.33 to 235.26.4.62235.26.4.6330
35235.26.4.64/27235.26.4.65 to 235.26.4.94235.26.4.9530
36235.26.4.96/27235.26.4.97 to 235.26.4.126235.26.4.12730
37235.26.4.128/27235.26.4.129 to 235.26.4.158235.26.4.15930
38235.26.4.160/27235.26.4.161 to 235.26.4.190235.26.4.19130
39235.26.4.192/27235.26.4.193 to 235.26.4.222235.26.4.22330
40235.26.4.224/27235.26.4.225 to 235.26.4.254235.26.4.25530
41235.26.5.0/27235.26.5.1 to 235.26.5.30235.26.5.3130
42235.26.5.32/27235.26.5.33 to 235.26.5.62235.26.5.6330
43235.26.5.64/27235.26.5.65 to 235.26.5.94235.26.5.9530
44235.26.5.96/27235.26.5.97 to 235.26.5.126235.26.5.12730
45235.26.5.128/27235.26.5.129 to 235.26.5.158235.26.5.15930
46235.26.5.160/27235.26.5.161 to 235.26.5.190235.26.5.19130
47235.26.5.192/27235.26.5.193 to 235.26.5.222235.26.5.22330
48235.26.5.224/27235.26.5.225 to 235.26.5.254235.26.5.25530
49235.26.6.0/27235.26.6.1 to 235.26.6.30235.26.6.3130
50235.26.6.32/27235.26.6.33 to 235.26.6.62235.26.6.6330
51235.26.6.64/27235.26.6.65 to 235.26.6.94235.26.6.9530
52235.26.6.96/27235.26.6.97 to 235.26.6.126235.26.6.12730
53235.26.6.128/27235.26.6.129 to 235.26.6.158235.26.6.15930
54235.26.6.160/27235.26.6.161 to 235.26.6.190235.26.6.19130
55235.26.6.192/27235.26.6.193 to 235.26.6.222235.26.6.22330
56235.26.6.224/27235.26.6.225 to 235.26.6.254235.26.6.25530
57235.26.7.0/27235.26.7.1 to 235.26.7.30235.26.7.3130
58235.26.7.32/27235.26.7.33 to 235.26.7.62235.26.7.6330
59235.26.7.64/27235.26.7.65 to 235.26.7.94235.26.7.9530
60235.26.7.96/27235.26.7.97 to 235.26.7.126235.26.7.12730
61235.26.7.128/27235.26.7.129 to 235.26.7.158235.26.7.15930
62235.26.7.160/27235.26.7.161 to 235.26.7.190235.26.7.19130
63235.26.7.192/27235.26.7.193 to 235.26.7.222235.26.7.22330
64235.26.7.224/27235.26.7.225 to 235.26.7.254235.26.7.25530
65235.26.8.0/27235.26.8.1 to 235.26.8.30235.26.8.3130
66235.26.8.32/27235.26.8.33 to 235.26.8.62235.26.8.6330
67235.26.8.64/27235.26.8.65 to 235.26.8.94235.26.8.9530
68235.26.8.96/27235.26.8.97 to 235.26.8.126235.26.8.12730
69235.26.8.128/27235.26.8.129 to 235.26.8.158235.26.8.15930
70235.26.8.160/27235.26.8.161 to 235.26.8.190235.26.8.19130
71235.26.8.192/27235.26.8.193 to 235.26.8.222235.26.8.22330
72235.26.8.224/27235.26.8.225 to 235.26.8.254235.26.8.25530
73235.26.9.0/27235.26.9.1 to 235.26.9.30235.26.9.3130
74235.26.9.32/27235.26.9.33 to 235.26.9.62235.26.9.6330
75235.26.9.64/27235.26.9.65 to 235.26.9.94235.26.9.9530
76235.26.9.96/27235.26.9.97 to 235.26.9.126235.26.9.12730
77235.26.9.128/27235.26.9.129 to 235.26.9.158235.26.9.15930
78235.26.9.160/27235.26.9.161 to 235.26.9.190235.26.9.19130
79235.26.9.192/27235.26.9.193 to 235.26.9.222235.26.9.22330
80235.26.9.224/27235.26.9.225 to 235.26.9.254235.26.9.25530
81235.26.10.0/27235.26.10.1 to 235.26.10.30235.26.10.3130
82235.26.10.32/27235.26.10.33 to 235.26.10.62235.26.10.6330
83235.26.10.64/27235.26.10.65 to 235.26.10.94235.26.10.9530
84235.26.10.96/27235.26.10.97 to 235.26.10.126235.26.10.12730
85235.26.10.128/27235.26.10.129 to 235.26.10.158235.26.10.15930
86235.26.10.160/27235.26.10.161 to 235.26.10.190235.26.10.19130
87235.26.10.192/27235.26.10.193 to 235.26.10.222235.26.10.22330
88235.26.10.224/27235.26.10.225 to 235.26.10.254235.26.10.25530
89235.26.11.0/27235.26.11.1 to 235.26.11.30235.26.11.3130
90235.26.11.32/27235.26.11.33 to 235.26.11.62235.26.11.6330
91235.26.11.64/27235.26.11.65 to 235.26.11.94235.26.11.9530
92235.26.11.96/27235.26.11.97 to 235.26.11.126235.26.11.12730
93235.26.11.128/27235.26.11.129 to 235.26.11.158235.26.11.15930
94235.26.11.160/27235.26.11.161 to 235.26.11.190235.26.11.19130
95235.26.11.192/27235.26.11.193 to 235.26.11.222235.26.11.22330
96235.26.11.224/27235.26.11.225 to 235.26.11.254235.26.11.25530
97235.26.12.0/27235.26.12.1 to 235.26.12.30235.26.12.3130
98235.26.12.32/27235.26.12.33 to 235.26.12.62235.26.12.6330
99235.26.12.64/27235.26.12.65 to 235.26.12.94235.26.12.9530
100235.26.12.96/27235.26.12.97 to 235.26.12.126235.26.12.12730
101235.26.12.128/27235.26.12.129 to 235.26.12.158235.26.12.15930
102235.26.12.160/27235.26.12.161 to 235.26.12.190235.26.12.19130
103235.26.12.192/27235.26.12.193 to 235.26.12.222235.26.12.22330
104235.26.12.224/27235.26.12.225 to 235.26.12.254235.26.12.25530
105235.26.13.0/27235.26.13.1 to 235.26.13.30235.26.13.3130
106235.26.13.32/27235.26.13.33 to 235.26.13.62235.26.13.6330
107235.26.13.64/27235.26.13.65 to 235.26.13.94235.26.13.9530
108235.26.13.96/27235.26.13.97 to 235.26.13.126235.26.13.12730
109235.26.13.128/27235.26.13.129 to 235.26.13.158235.26.13.15930
110235.26.13.160/27235.26.13.161 to 235.26.13.190235.26.13.19130
111235.26.13.192/27235.26.13.193 to 235.26.13.222235.26.13.22330
112235.26.13.224/27235.26.13.225 to 235.26.13.254235.26.13.25530
113235.26.14.0/27235.26.14.1 to 235.26.14.30235.26.14.3130
114235.26.14.32/27235.26.14.33 to 235.26.14.62235.26.14.6330
115235.26.14.64/27235.26.14.65 to 235.26.14.94235.26.14.9530
116235.26.14.96/27235.26.14.97 to 235.26.14.126235.26.14.12730
117235.26.14.128/27235.26.14.129 to 235.26.14.158235.26.14.15930
118235.26.14.160/27235.26.14.161 to 235.26.14.190235.26.14.19130
119235.26.14.192/27235.26.14.193 to 235.26.14.222235.26.14.22330
120235.26.14.224/27235.26.14.225 to 235.26.14.254235.26.14.25530
121235.26.15.0/27235.26.15.1 to 235.26.15.30235.26.15.3130
122235.26.15.32/27235.26.15.33 to 235.26.15.62235.26.15.6330
123235.26.15.64/27235.26.15.65 to 235.26.15.94235.26.15.9530
124235.26.15.96/27235.26.15.97 to 235.26.15.126235.26.15.12730
125235.26.15.128/27235.26.15.129 to 235.26.15.158235.26.15.15930
126235.26.15.160/27235.26.15.161 to 235.26.15.190235.26.15.19130
127235.26.15.192/27235.26.15.193 to 235.26.15.222235.26.15.22330
128235.26.15.224/27235.26.15.225 to 235.26.15.254235.26.15.25530
129235.26.16.0/27235.26.16.1 to 235.26.16.30235.26.16.3130
130235.26.16.32/27235.26.16.33 to 235.26.16.62235.26.16.6330
131235.26.16.64/27235.26.16.65 to 235.26.16.94235.26.16.9530
132235.26.16.96/27235.26.16.97 to 235.26.16.126235.26.16.12730
133235.26.16.128/27235.26.16.129 to 235.26.16.158235.26.16.15930
134235.26.16.160/27235.26.16.161 to 235.26.16.190235.26.16.19130
135235.26.16.192/27235.26.16.193 to 235.26.16.222235.26.16.22330
136235.26.16.224/27235.26.16.225 to 235.26.16.254235.26.16.25530
137235.26.17.0/27235.26.17.1 to 235.26.17.30235.26.17.3130
138235.26.17.32/27235.26.17.33 to 235.26.17.62235.26.17.6330
139235.26.17.64/27235.26.17.65 to 235.26.17.94235.26.17.9530
140235.26.17.96/27235.26.17.97 to 235.26.17.126235.26.17.12730
141235.26.17.128/27235.26.17.129 to 235.26.17.158235.26.17.15930
142235.26.17.160/27235.26.17.161 to 235.26.17.190235.26.17.19130
143235.26.17.192/27235.26.17.193 to 235.26.17.222235.26.17.22330
144235.26.17.224/27235.26.17.225 to 235.26.17.254235.26.17.25530
145235.26.18.0/27235.26.18.1 to 235.26.18.30235.26.18.3130
146235.26.18.32/27235.26.18.33 to 235.26.18.62235.26.18.6330
147235.26.18.64/27235.26.18.65 to 235.26.18.94235.26.18.9530
148235.26.18.96/27235.26.18.97 to 235.26.18.126235.26.18.12730
149235.26.18.128/27235.26.18.129 to 235.26.18.158235.26.18.15930
150235.26.18.160/27235.26.18.161 to 235.26.18.190235.26.18.19130
151235.26.18.192/27235.26.18.193 to 235.26.18.222235.26.18.22330
152235.26.18.224/27235.26.18.225 to 235.26.18.254235.26.18.25530
153235.26.19.0/27235.26.19.1 to 235.26.19.30235.26.19.3130
154235.26.19.32/27235.26.19.33 to 235.26.19.62235.26.19.6330
155235.26.19.64/27235.26.19.65 to 235.26.19.94235.26.19.9530
156235.26.19.96/27235.26.19.97 to 235.26.19.126235.26.19.12730
157235.26.19.128/27235.26.19.129 to 235.26.19.158235.26.19.15930
158235.26.19.160/27235.26.19.161 to 235.26.19.190235.26.19.19130
159235.26.19.192/27235.26.19.193 to 235.26.19.222235.26.19.22330
160235.26.19.224/27235.26.19.225 to 235.26.19.254235.26.19.25530
161235.26.20.0/27235.26.20.1 to 235.26.20.30235.26.20.3130
162235.26.20.32/27235.26.20.33 to 235.26.20.62235.26.20.6330
163235.26.20.64/27235.26.20.65 to 235.26.20.94235.26.20.9530
164235.26.20.96/27235.26.20.97 to 235.26.20.126235.26.20.12730
165235.26.20.128/27235.26.20.129 to 235.26.20.158235.26.20.15930
166235.26.20.160/27235.26.20.161 to 235.26.20.190235.26.20.19130
167235.26.20.192/27235.26.20.193 to 235.26.20.222235.26.20.22330
168235.26.20.224/27235.26.20.225 to 235.26.20.254235.26.20.25530
169235.26.21.0/27235.26.21.1 to 235.26.21.30235.26.21.3130
170235.26.21.32/27235.26.21.33 to 235.26.21.62235.26.21.6330
171235.26.21.64/27235.26.21.65 to 235.26.21.94235.26.21.9530
172235.26.21.96/27235.26.21.97 to 235.26.21.126235.26.21.12730
173235.26.21.128/27235.26.21.129 to 235.26.21.158235.26.21.15930
174235.26.21.160/27235.26.21.161 to 235.26.21.190235.26.21.19130
175235.26.21.192/27235.26.21.193 to 235.26.21.222235.26.21.22330
176235.26.21.224/27235.26.21.225 to 235.26.21.254235.26.21.25530
177235.26.22.0/27235.26.22.1 to 235.26.22.30235.26.22.3130
178235.26.22.32/27235.26.22.33 to 235.26.22.62235.26.22.6330
179235.26.22.64/27235.26.22.65 to 235.26.22.94235.26.22.9530
180235.26.22.96/27235.26.22.97 to 235.26.22.126235.26.22.12730
181235.26.22.128/27235.26.22.129 to 235.26.22.158235.26.22.15930
182235.26.22.160/27235.26.22.161 to 235.26.22.190235.26.22.19130
183235.26.22.192/27235.26.22.193 to 235.26.22.222235.26.22.22330
184235.26.22.224/27235.26.22.225 to 235.26.22.254235.26.22.25530
185235.26.23.0/27235.26.23.1 to 235.26.23.30235.26.23.3130
186235.26.23.32/27235.26.23.33 to 235.26.23.62235.26.23.6330
187235.26.23.64/27235.26.23.65 to 235.26.23.94235.26.23.9530
188235.26.23.96/27235.26.23.97 to 235.26.23.126235.26.23.12730
189235.26.23.128/27235.26.23.129 to 235.26.23.158235.26.23.15930
190235.26.23.160/27235.26.23.161 to 235.26.23.190235.26.23.19130
191235.26.23.192/27235.26.23.193 to 235.26.23.222235.26.23.22330
192235.26.23.224/27235.26.23.225 to 235.26.23.254235.26.23.25530
193235.26.24.0/27235.26.24.1 to 235.26.24.30235.26.24.3130
194235.26.24.32/27235.26.24.33 to 235.26.24.62235.26.24.6330
195235.26.24.64/27235.26.24.65 to 235.26.24.94235.26.24.9530
196235.26.24.96/27235.26.24.97 to 235.26.24.126235.26.24.12730
197235.26.24.128/27235.26.24.129 to 235.26.24.158235.26.24.15930
198235.26.24.160/27235.26.24.161 to 235.26.24.190235.26.24.19130
199235.26.24.192/27235.26.24.193 to 235.26.24.222235.26.24.22330
200235.26.24.224/27235.26.24.225 to 235.26.24.254235.26.24.25530
201235.26.25.0/27235.26.25.1 to 235.26.25.30235.26.25.3130
202235.26.25.32/27235.26.25.33 to 235.26.25.62235.26.25.6330
203235.26.25.64/27235.26.25.65 to 235.26.25.94235.26.25.9530
204235.26.25.96/27235.26.25.97 to 235.26.25.126235.26.25.12730
205235.26.25.128/27235.26.25.129 to 235.26.25.158235.26.25.15930
206235.26.25.160/27235.26.25.161 to 235.26.25.190235.26.25.19130
207235.26.25.192/27235.26.25.193 to 235.26.25.222235.26.25.22330
208235.26.25.224/27235.26.25.225 to 235.26.25.254235.26.25.25530
209235.26.26.0/27235.26.26.1 to 235.26.26.30235.26.26.3130
210235.26.26.32/27235.26.26.33 to 235.26.26.62235.26.26.6330
211235.26.26.64/27235.26.26.65 to 235.26.26.94235.26.26.9530
212235.26.26.96/27235.26.26.97 to 235.26.26.126235.26.26.12730
213235.26.26.128/27235.26.26.129 to 235.26.26.158235.26.26.15930
214235.26.26.160/27235.26.26.161 to 235.26.26.190235.26.26.19130
215235.26.26.192/27235.26.26.193 to 235.26.26.222235.26.26.22330
216235.26.26.224/27235.26.26.225 to 235.26.26.254235.26.26.25530
217235.26.27.0/27235.26.27.1 to 235.26.27.30235.26.27.3130
218235.26.27.32/27235.26.27.33 to 235.26.27.62235.26.27.6330
219235.26.27.64/27235.26.27.65 to 235.26.27.94235.26.27.9530
220235.26.27.96/27235.26.27.97 to 235.26.27.126235.26.27.12730
221235.26.27.128/27235.26.27.129 to 235.26.27.158235.26.27.15930
222235.26.27.160/27235.26.27.161 to 235.26.27.190235.26.27.19130
223235.26.27.192/27235.26.27.193 to 235.26.27.222235.26.27.22330
224235.26.27.224/27235.26.27.225 to 235.26.27.254235.26.27.25530
225235.26.28.0/27235.26.28.1 to 235.26.28.30235.26.28.3130
226235.26.28.32/27235.26.28.33 to 235.26.28.62235.26.28.6330
227235.26.28.64/27235.26.28.65 to 235.26.28.94235.26.28.9530
228235.26.28.96/27235.26.28.97 to 235.26.28.126235.26.28.12730
229235.26.28.128/27235.26.28.129 to 235.26.28.158235.26.28.15930
230235.26.28.160/27235.26.28.161 to 235.26.28.190235.26.28.19130
231235.26.28.192/27235.26.28.193 to 235.26.28.222235.26.28.22330
232235.26.28.224/27235.26.28.225 to 235.26.28.254235.26.28.25530
233235.26.29.0/27235.26.29.1 to 235.26.29.30235.26.29.3130
234235.26.29.32/27235.26.29.33 to 235.26.29.62235.26.29.6330
235235.26.29.64/27235.26.29.65 to 235.26.29.94235.26.29.9530
236235.26.29.96/27235.26.29.97 to 235.26.29.126235.26.29.12730
237235.26.29.128/27235.26.29.129 to 235.26.29.158235.26.29.15930
238235.26.29.160/27235.26.29.161 to 235.26.29.190235.26.29.19130
239235.26.29.192/27235.26.29.193 to 235.26.29.222235.26.29.22330
240235.26.29.224/27235.26.29.225 to 235.26.29.254235.26.29.25530
241235.26.30.0/27235.26.30.1 to 235.26.30.30235.26.30.3130
242235.26.30.32/27235.26.30.33 to 235.26.30.62235.26.30.6330
243235.26.30.64/27235.26.30.65 to 235.26.30.94235.26.30.9530
244235.26.30.96/27235.26.30.97 to 235.26.30.126235.26.30.12730
245235.26.30.128/27235.26.30.129 to 235.26.30.158235.26.30.15930
246235.26.30.160/27235.26.30.161 to 235.26.30.190235.26.30.19130
247235.26.30.192/27235.26.30.193 to 235.26.30.222235.26.30.22330
248235.26.30.224/27235.26.30.225 to 235.26.30.254235.26.30.25530
249235.26.31.0/27235.26.31.1 to 235.26.31.30235.26.31.3130
250235.26.31.32/27235.26.31.33 to 235.26.31.62235.26.31.6330
251235.26.31.64/27235.26.31.65 to 235.26.31.94235.26.31.9530
252235.26.31.96/27235.26.31.97 to 235.26.31.126235.26.31.12730
253235.26.31.128/27235.26.31.129 to 235.26.31.158235.26.31.15930
254235.26.31.160/27235.26.31.161 to 235.26.31.190235.26.31.19130
255235.26.31.192/27235.26.31.193 to 235.26.31.222235.26.31.22330
256235.26.31.224/27235.26.31.225 to 235.26.31.254235.26.31.25530

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.