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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.

Network232.53.0.0/17
Usable hosts32,766
Subnet mask255.255.128.0
Addresses32,768
Network address
232.53.0.0
Broadcast address
232.53.127.255
First usable
232.53.0.1
Last usable
232.53.127.254
Usable hosts
32,766 (32,768 less the network and broadcast addresses)
Subnet mask
255.255.128.0
Wildcard mask
0.0.127.255 (Cisco ACLs, OSPF)
Prefix length
/17
Type
Multicast 224.0.0.0/4
One-to-many traffic, such as IPTV and routing protocols
Old class
D (multicast)
As numbers
Hex E8350000 · Integer 3895787520 to 3895820287
Reverse DNS zones
0.53.232.in-addr.arpa
1.53.232.in-addr.arpa
2.53.232.in-addr.arpa
3.53.232.in-addr.arpa
4.53.232.in-addr.arpa
5.53.232.in-addr.arpa
6.53.232.in-addr.arpa
7.53.232.in-addr.arpa
8.53.232.in-addr.arpa
9.53.232.in-addr.arpa
10.53.232.in-addr.arpa
11.53.232.in-addr.arpa
12.53.232.in-addr.arpa
13.53.232.in-addr.arpa
14.53.232.in-addr.arpa
15.53.232.in-addr.arpa
and 112 more
/17 is not on a 8-bit boundary, so it takes 128 /24 zones.
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address11101000.00110101.00000000.00000000232.53.0.0
Subnet mask11111111.11111111.10000000.00000000255.255.128.0
Network11101000.00110101.00000000.00000000232.53.0.0
Broadcast11101000.00110101.01111111.11111111232.53.127.255
Split into smaller subnets/27
/18 (2)/19 (4)/20 (8)/21 (16)/22 (32)/23 (64)/24 (128)/25 (256)/26 (512)/27 (1,024)/28 (2,048)/29 (4,096)

232.53.0.0/17 makes 1,024 subnets of /27; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
1232.53.0.0/27232.53.0.1 to 232.53.0.30232.53.0.3130
2232.53.0.32/27232.53.0.33 to 232.53.0.62232.53.0.6330
3232.53.0.64/27232.53.0.65 to 232.53.0.94232.53.0.9530
4232.53.0.96/27232.53.0.97 to 232.53.0.126232.53.0.12730
5232.53.0.128/27232.53.0.129 to 232.53.0.158232.53.0.15930
6232.53.0.160/27232.53.0.161 to 232.53.0.190232.53.0.19130
7232.53.0.192/27232.53.0.193 to 232.53.0.222232.53.0.22330
8232.53.0.224/27232.53.0.225 to 232.53.0.254232.53.0.25530
9232.53.1.0/27232.53.1.1 to 232.53.1.30232.53.1.3130
10232.53.1.32/27232.53.1.33 to 232.53.1.62232.53.1.6330
11232.53.1.64/27232.53.1.65 to 232.53.1.94232.53.1.9530
12232.53.1.96/27232.53.1.97 to 232.53.1.126232.53.1.12730
13232.53.1.128/27232.53.1.129 to 232.53.1.158232.53.1.15930
14232.53.1.160/27232.53.1.161 to 232.53.1.190232.53.1.19130
15232.53.1.192/27232.53.1.193 to 232.53.1.222232.53.1.22330
16232.53.1.224/27232.53.1.225 to 232.53.1.254232.53.1.25530
17232.53.2.0/27232.53.2.1 to 232.53.2.30232.53.2.3130
18232.53.2.32/27232.53.2.33 to 232.53.2.62232.53.2.6330
19232.53.2.64/27232.53.2.65 to 232.53.2.94232.53.2.9530
20232.53.2.96/27232.53.2.97 to 232.53.2.126232.53.2.12730
21232.53.2.128/27232.53.2.129 to 232.53.2.158232.53.2.15930
22232.53.2.160/27232.53.2.161 to 232.53.2.190232.53.2.19130
23232.53.2.192/27232.53.2.193 to 232.53.2.222232.53.2.22330
24232.53.2.224/27232.53.2.225 to 232.53.2.254232.53.2.25530
25232.53.3.0/27232.53.3.1 to 232.53.3.30232.53.3.3130
26232.53.3.32/27232.53.3.33 to 232.53.3.62232.53.3.6330
27232.53.3.64/27232.53.3.65 to 232.53.3.94232.53.3.9530
28232.53.3.96/27232.53.3.97 to 232.53.3.126232.53.3.12730
29232.53.3.128/27232.53.3.129 to 232.53.3.158232.53.3.15930
30232.53.3.160/27232.53.3.161 to 232.53.3.190232.53.3.19130
31232.53.3.192/27232.53.3.193 to 232.53.3.222232.53.3.22330
32232.53.3.224/27232.53.3.225 to 232.53.3.254232.53.3.25530
33232.53.4.0/27232.53.4.1 to 232.53.4.30232.53.4.3130
34232.53.4.32/27232.53.4.33 to 232.53.4.62232.53.4.6330
35232.53.4.64/27232.53.4.65 to 232.53.4.94232.53.4.9530
36232.53.4.96/27232.53.4.97 to 232.53.4.126232.53.4.12730
37232.53.4.128/27232.53.4.129 to 232.53.4.158232.53.4.15930
38232.53.4.160/27232.53.4.161 to 232.53.4.190232.53.4.19130
39232.53.4.192/27232.53.4.193 to 232.53.4.222232.53.4.22330
40232.53.4.224/27232.53.4.225 to 232.53.4.254232.53.4.25530
41232.53.5.0/27232.53.5.1 to 232.53.5.30232.53.5.3130
42232.53.5.32/27232.53.5.33 to 232.53.5.62232.53.5.6330
43232.53.5.64/27232.53.5.65 to 232.53.5.94232.53.5.9530
44232.53.5.96/27232.53.5.97 to 232.53.5.126232.53.5.12730
45232.53.5.128/27232.53.5.129 to 232.53.5.158232.53.5.15930
46232.53.5.160/27232.53.5.161 to 232.53.5.190232.53.5.19130
47232.53.5.192/27232.53.5.193 to 232.53.5.222232.53.5.22330
48232.53.5.224/27232.53.5.225 to 232.53.5.254232.53.5.25530
49232.53.6.0/27232.53.6.1 to 232.53.6.30232.53.6.3130
50232.53.6.32/27232.53.6.33 to 232.53.6.62232.53.6.6330
51232.53.6.64/27232.53.6.65 to 232.53.6.94232.53.6.9530
52232.53.6.96/27232.53.6.97 to 232.53.6.126232.53.6.12730
53232.53.6.128/27232.53.6.129 to 232.53.6.158232.53.6.15930
54232.53.6.160/27232.53.6.161 to 232.53.6.190232.53.6.19130
55232.53.6.192/27232.53.6.193 to 232.53.6.222232.53.6.22330
56232.53.6.224/27232.53.6.225 to 232.53.6.254232.53.6.25530
57232.53.7.0/27232.53.7.1 to 232.53.7.30232.53.7.3130
58232.53.7.32/27232.53.7.33 to 232.53.7.62232.53.7.6330
59232.53.7.64/27232.53.7.65 to 232.53.7.94232.53.7.9530
60232.53.7.96/27232.53.7.97 to 232.53.7.126232.53.7.12730
61232.53.7.128/27232.53.7.129 to 232.53.7.158232.53.7.15930
62232.53.7.160/27232.53.7.161 to 232.53.7.190232.53.7.19130
63232.53.7.192/27232.53.7.193 to 232.53.7.222232.53.7.22330
64232.53.7.224/27232.53.7.225 to 232.53.7.254232.53.7.25530
65232.53.8.0/27232.53.8.1 to 232.53.8.30232.53.8.3130
66232.53.8.32/27232.53.8.33 to 232.53.8.62232.53.8.6330
67232.53.8.64/27232.53.8.65 to 232.53.8.94232.53.8.9530
68232.53.8.96/27232.53.8.97 to 232.53.8.126232.53.8.12730
69232.53.8.128/27232.53.8.129 to 232.53.8.158232.53.8.15930
70232.53.8.160/27232.53.8.161 to 232.53.8.190232.53.8.19130
71232.53.8.192/27232.53.8.193 to 232.53.8.222232.53.8.22330
72232.53.8.224/27232.53.8.225 to 232.53.8.254232.53.8.25530
73232.53.9.0/27232.53.9.1 to 232.53.9.30232.53.9.3130
74232.53.9.32/27232.53.9.33 to 232.53.9.62232.53.9.6330
75232.53.9.64/27232.53.9.65 to 232.53.9.94232.53.9.9530
76232.53.9.96/27232.53.9.97 to 232.53.9.126232.53.9.12730
77232.53.9.128/27232.53.9.129 to 232.53.9.158232.53.9.15930
78232.53.9.160/27232.53.9.161 to 232.53.9.190232.53.9.19130
79232.53.9.192/27232.53.9.193 to 232.53.9.222232.53.9.22330
80232.53.9.224/27232.53.9.225 to 232.53.9.254232.53.9.25530
81232.53.10.0/27232.53.10.1 to 232.53.10.30232.53.10.3130
82232.53.10.32/27232.53.10.33 to 232.53.10.62232.53.10.6330
83232.53.10.64/27232.53.10.65 to 232.53.10.94232.53.10.9530
84232.53.10.96/27232.53.10.97 to 232.53.10.126232.53.10.12730
85232.53.10.128/27232.53.10.129 to 232.53.10.158232.53.10.15930
86232.53.10.160/27232.53.10.161 to 232.53.10.190232.53.10.19130
87232.53.10.192/27232.53.10.193 to 232.53.10.222232.53.10.22330
88232.53.10.224/27232.53.10.225 to 232.53.10.254232.53.10.25530
89232.53.11.0/27232.53.11.1 to 232.53.11.30232.53.11.3130
90232.53.11.32/27232.53.11.33 to 232.53.11.62232.53.11.6330
91232.53.11.64/27232.53.11.65 to 232.53.11.94232.53.11.9530
92232.53.11.96/27232.53.11.97 to 232.53.11.126232.53.11.12730
93232.53.11.128/27232.53.11.129 to 232.53.11.158232.53.11.15930
94232.53.11.160/27232.53.11.161 to 232.53.11.190232.53.11.19130
95232.53.11.192/27232.53.11.193 to 232.53.11.222232.53.11.22330
96232.53.11.224/27232.53.11.225 to 232.53.11.254232.53.11.25530
97232.53.12.0/27232.53.12.1 to 232.53.12.30232.53.12.3130
98232.53.12.32/27232.53.12.33 to 232.53.12.62232.53.12.6330
99232.53.12.64/27232.53.12.65 to 232.53.12.94232.53.12.9530
100232.53.12.96/27232.53.12.97 to 232.53.12.126232.53.12.12730
101232.53.12.128/27232.53.12.129 to 232.53.12.158232.53.12.15930
102232.53.12.160/27232.53.12.161 to 232.53.12.190232.53.12.19130
103232.53.12.192/27232.53.12.193 to 232.53.12.222232.53.12.22330
104232.53.12.224/27232.53.12.225 to 232.53.12.254232.53.12.25530
105232.53.13.0/27232.53.13.1 to 232.53.13.30232.53.13.3130
106232.53.13.32/27232.53.13.33 to 232.53.13.62232.53.13.6330
107232.53.13.64/27232.53.13.65 to 232.53.13.94232.53.13.9530
108232.53.13.96/27232.53.13.97 to 232.53.13.126232.53.13.12730
109232.53.13.128/27232.53.13.129 to 232.53.13.158232.53.13.15930
110232.53.13.160/27232.53.13.161 to 232.53.13.190232.53.13.19130
111232.53.13.192/27232.53.13.193 to 232.53.13.222232.53.13.22330
112232.53.13.224/27232.53.13.225 to 232.53.13.254232.53.13.25530
113232.53.14.0/27232.53.14.1 to 232.53.14.30232.53.14.3130
114232.53.14.32/27232.53.14.33 to 232.53.14.62232.53.14.6330
115232.53.14.64/27232.53.14.65 to 232.53.14.94232.53.14.9530
116232.53.14.96/27232.53.14.97 to 232.53.14.126232.53.14.12730
117232.53.14.128/27232.53.14.129 to 232.53.14.158232.53.14.15930
118232.53.14.160/27232.53.14.161 to 232.53.14.190232.53.14.19130
119232.53.14.192/27232.53.14.193 to 232.53.14.222232.53.14.22330
120232.53.14.224/27232.53.14.225 to 232.53.14.254232.53.14.25530
121232.53.15.0/27232.53.15.1 to 232.53.15.30232.53.15.3130
122232.53.15.32/27232.53.15.33 to 232.53.15.62232.53.15.6330
123232.53.15.64/27232.53.15.65 to 232.53.15.94232.53.15.9530
124232.53.15.96/27232.53.15.97 to 232.53.15.126232.53.15.12730
125232.53.15.128/27232.53.15.129 to 232.53.15.158232.53.15.15930
126232.53.15.160/27232.53.15.161 to 232.53.15.190232.53.15.19130
127232.53.15.192/27232.53.15.193 to 232.53.15.222232.53.15.22330
128232.53.15.224/27232.53.15.225 to 232.53.15.254232.53.15.25530
129232.53.16.0/27232.53.16.1 to 232.53.16.30232.53.16.3130
130232.53.16.32/27232.53.16.33 to 232.53.16.62232.53.16.6330
131232.53.16.64/27232.53.16.65 to 232.53.16.94232.53.16.9530
132232.53.16.96/27232.53.16.97 to 232.53.16.126232.53.16.12730
133232.53.16.128/27232.53.16.129 to 232.53.16.158232.53.16.15930
134232.53.16.160/27232.53.16.161 to 232.53.16.190232.53.16.19130
135232.53.16.192/27232.53.16.193 to 232.53.16.222232.53.16.22330
136232.53.16.224/27232.53.16.225 to 232.53.16.254232.53.16.25530
137232.53.17.0/27232.53.17.1 to 232.53.17.30232.53.17.3130
138232.53.17.32/27232.53.17.33 to 232.53.17.62232.53.17.6330
139232.53.17.64/27232.53.17.65 to 232.53.17.94232.53.17.9530
140232.53.17.96/27232.53.17.97 to 232.53.17.126232.53.17.12730
141232.53.17.128/27232.53.17.129 to 232.53.17.158232.53.17.15930
142232.53.17.160/27232.53.17.161 to 232.53.17.190232.53.17.19130
143232.53.17.192/27232.53.17.193 to 232.53.17.222232.53.17.22330
144232.53.17.224/27232.53.17.225 to 232.53.17.254232.53.17.25530
145232.53.18.0/27232.53.18.1 to 232.53.18.30232.53.18.3130
146232.53.18.32/27232.53.18.33 to 232.53.18.62232.53.18.6330
147232.53.18.64/27232.53.18.65 to 232.53.18.94232.53.18.9530
148232.53.18.96/27232.53.18.97 to 232.53.18.126232.53.18.12730
149232.53.18.128/27232.53.18.129 to 232.53.18.158232.53.18.15930
150232.53.18.160/27232.53.18.161 to 232.53.18.190232.53.18.19130
151232.53.18.192/27232.53.18.193 to 232.53.18.222232.53.18.22330
152232.53.18.224/27232.53.18.225 to 232.53.18.254232.53.18.25530
153232.53.19.0/27232.53.19.1 to 232.53.19.30232.53.19.3130
154232.53.19.32/27232.53.19.33 to 232.53.19.62232.53.19.6330
155232.53.19.64/27232.53.19.65 to 232.53.19.94232.53.19.9530
156232.53.19.96/27232.53.19.97 to 232.53.19.126232.53.19.12730
157232.53.19.128/27232.53.19.129 to 232.53.19.158232.53.19.15930
158232.53.19.160/27232.53.19.161 to 232.53.19.190232.53.19.19130
159232.53.19.192/27232.53.19.193 to 232.53.19.222232.53.19.22330
160232.53.19.224/27232.53.19.225 to 232.53.19.254232.53.19.25530
161232.53.20.0/27232.53.20.1 to 232.53.20.30232.53.20.3130
162232.53.20.32/27232.53.20.33 to 232.53.20.62232.53.20.6330
163232.53.20.64/27232.53.20.65 to 232.53.20.94232.53.20.9530
164232.53.20.96/27232.53.20.97 to 232.53.20.126232.53.20.12730
165232.53.20.128/27232.53.20.129 to 232.53.20.158232.53.20.15930
166232.53.20.160/27232.53.20.161 to 232.53.20.190232.53.20.19130
167232.53.20.192/27232.53.20.193 to 232.53.20.222232.53.20.22330
168232.53.20.224/27232.53.20.225 to 232.53.20.254232.53.20.25530
169232.53.21.0/27232.53.21.1 to 232.53.21.30232.53.21.3130
170232.53.21.32/27232.53.21.33 to 232.53.21.62232.53.21.6330
171232.53.21.64/27232.53.21.65 to 232.53.21.94232.53.21.9530
172232.53.21.96/27232.53.21.97 to 232.53.21.126232.53.21.12730
173232.53.21.128/27232.53.21.129 to 232.53.21.158232.53.21.15930
174232.53.21.160/27232.53.21.161 to 232.53.21.190232.53.21.19130
175232.53.21.192/27232.53.21.193 to 232.53.21.222232.53.21.22330
176232.53.21.224/27232.53.21.225 to 232.53.21.254232.53.21.25530
177232.53.22.0/27232.53.22.1 to 232.53.22.30232.53.22.3130
178232.53.22.32/27232.53.22.33 to 232.53.22.62232.53.22.6330
179232.53.22.64/27232.53.22.65 to 232.53.22.94232.53.22.9530
180232.53.22.96/27232.53.22.97 to 232.53.22.126232.53.22.12730
181232.53.22.128/27232.53.22.129 to 232.53.22.158232.53.22.15930
182232.53.22.160/27232.53.22.161 to 232.53.22.190232.53.22.19130
183232.53.22.192/27232.53.22.193 to 232.53.22.222232.53.22.22330
184232.53.22.224/27232.53.22.225 to 232.53.22.254232.53.22.25530
185232.53.23.0/27232.53.23.1 to 232.53.23.30232.53.23.3130
186232.53.23.32/27232.53.23.33 to 232.53.23.62232.53.23.6330
187232.53.23.64/27232.53.23.65 to 232.53.23.94232.53.23.9530
188232.53.23.96/27232.53.23.97 to 232.53.23.126232.53.23.12730
189232.53.23.128/27232.53.23.129 to 232.53.23.158232.53.23.15930
190232.53.23.160/27232.53.23.161 to 232.53.23.190232.53.23.19130
191232.53.23.192/27232.53.23.193 to 232.53.23.222232.53.23.22330
192232.53.23.224/27232.53.23.225 to 232.53.23.254232.53.23.25530
193232.53.24.0/27232.53.24.1 to 232.53.24.30232.53.24.3130
194232.53.24.32/27232.53.24.33 to 232.53.24.62232.53.24.6330
195232.53.24.64/27232.53.24.65 to 232.53.24.94232.53.24.9530
196232.53.24.96/27232.53.24.97 to 232.53.24.126232.53.24.12730
197232.53.24.128/27232.53.24.129 to 232.53.24.158232.53.24.15930
198232.53.24.160/27232.53.24.161 to 232.53.24.190232.53.24.19130
199232.53.24.192/27232.53.24.193 to 232.53.24.222232.53.24.22330
200232.53.24.224/27232.53.24.225 to 232.53.24.254232.53.24.25530
201232.53.25.0/27232.53.25.1 to 232.53.25.30232.53.25.3130
202232.53.25.32/27232.53.25.33 to 232.53.25.62232.53.25.6330
203232.53.25.64/27232.53.25.65 to 232.53.25.94232.53.25.9530
204232.53.25.96/27232.53.25.97 to 232.53.25.126232.53.25.12730
205232.53.25.128/27232.53.25.129 to 232.53.25.158232.53.25.15930
206232.53.25.160/27232.53.25.161 to 232.53.25.190232.53.25.19130
207232.53.25.192/27232.53.25.193 to 232.53.25.222232.53.25.22330
208232.53.25.224/27232.53.25.225 to 232.53.25.254232.53.25.25530
209232.53.26.0/27232.53.26.1 to 232.53.26.30232.53.26.3130
210232.53.26.32/27232.53.26.33 to 232.53.26.62232.53.26.6330
211232.53.26.64/27232.53.26.65 to 232.53.26.94232.53.26.9530
212232.53.26.96/27232.53.26.97 to 232.53.26.126232.53.26.12730
213232.53.26.128/27232.53.26.129 to 232.53.26.158232.53.26.15930
214232.53.26.160/27232.53.26.161 to 232.53.26.190232.53.26.19130
215232.53.26.192/27232.53.26.193 to 232.53.26.222232.53.26.22330
216232.53.26.224/27232.53.26.225 to 232.53.26.254232.53.26.25530
217232.53.27.0/27232.53.27.1 to 232.53.27.30232.53.27.3130
218232.53.27.32/27232.53.27.33 to 232.53.27.62232.53.27.6330
219232.53.27.64/27232.53.27.65 to 232.53.27.94232.53.27.9530
220232.53.27.96/27232.53.27.97 to 232.53.27.126232.53.27.12730
221232.53.27.128/27232.53.27.129 to 232.53.27.158232.53.27.15930
222232.53.27.160/27232.53.27.161 to 232.53.27.190232.53.27.19130
223232.53.27.192/27232.53.27.193 to 232.53.27.222232.53.27.22330
224232.53.27.224/27232.53.27.225 to 232.53.27.254232.53.27.25530
225232.53.28.0/27232.53.28.1 to 232.53.28.30232.53.28.3130
226232.53.28.32/27232.53.28.33 to 232.53.28.62232.53.28.6330
227232.53.28.64/27232.53.28.65 to 232.53.28.94232.53.28.9530
228232.53.28.96/27232.53.28.97 to 232.53.28.126232.53.28.12730
229232.53.28.128/27232.53.28.129 to 232.53.28.158232.53.28.15930
230232.53.28.160/27232.53.28.161 to 232.53.28.190232.53.28.19130
231232.53.28.192/27232.53.28.193 to 232.53.28.222232.53.28.22330
232232.53.28.224/27232.53.28.225 to 232.53.28.254232.53.28.25530
233232.53.29.0/27232.53.29.1 to 232.53.29.30232.53.29.3130
234232.53.29.32/27232.53.29.33 to 232.53.29.62232.53.29.6330
235232.53.29.64/27232.53.29.65 to 232.53.29.94232.53.29.9530
236232.53.29.96/27232.53.29.97 to 232.53.29.126232.53.29.12730
237232.53.29.128/27232.53.29.129 to 232.53.29.158232.53.29.15930
238232.53.29.160/27232.53.29.161 to 232.53.29.190232.53.29.19130
239232.53.29.192/27232.53.29.193 to 232.53.29.222232.53.29.22330
240232.53.29.224/27232.53.29.225 to 232.53.29.254232.53.29.25530
241232.53.30.0/27232.53.30.1 to 232.53.30.30232.53.30.3130
242232.53.30.32/27232.53.30.33 to 232.53.30.62232.53.30.6330
243232.53.30.64/27232.53.30.65 to 232.53.30.94232.53.30.9530
244232.53.30.96/27232.53.30.97 to 232.53.30.126232.53.30.12730
245232.53.30.128/27232.53.30.129 to 232.53.30.158232.53.30.15930
246232.53.30.160/27232.53.30.161 to 232.53.30.190232.53.30.19130
247232.53.30.192/27232.53.30.193 to 232.53.30.222232.53.30.22330
248232.53.30.224/27232.53.30.225 to 232.53.30.254232.53.30.25530
249232.53.31.0/27232.53.31.1 to 232.53.31.30232.53.31.3130
250232.53.31.32/27232.53.31.33 to 232.53.31.62232.53.31.6330
251232.53.31.64/27232.53.31.65 to 232.53.31.94232.53.31.9530
252232.53.31.96/27232.53.31.97 to 232.53.31.126232.53.31.12730
253232.53.31.128/27232.53.31.129 to 232.53.31.158232.53.31.15930
254232.53.31.160/27232.53.31.161 to 232.53.31.190232.53.31.19130
255232.53.31.192/27232.53.31.193 to 232.53.31.222232.53.31.22330
256232.53.31.224/27232.53.31.225 to 232.53.31.254232.53.31.25530

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.