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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.

Network134.0.0.0/7
Usable hosts33,554,430
Subnet mask254.0.0.0
Addresses33,554,432
Network address
134.0.0.0
Broadcast address
135.255.255.255
First usable
134.0.0.1
Last usable
135.255.255.254
Usable hosts
33,554,430 (33,554,432 less the network and broadcast addresses)
Subnet mask
254.0.0.0
Wildcard mask
1.255.255.255 (Cisco ACLs, OSPF)
Prefix length
/7
Type
Public public
Old class
B (default /16)
As numbers
Hex 86000000 · Integer 2248146944 to 2281701375
Reverse DNS zones
134.in-addr.arpa
135.in-addr.arpa
/7 is not on a 8-bit boundary, so it takes 2 /8 zones.
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address10000110.00000000.00000000.00000000134.0.0.0
Subnet mask11111110.00000000.00000000.00000000254.0.0.0
Network10000110.00000000.00000000.00000000134.0.0.0
Broadcast10000111.11111111.11111111.11111111135.255.255.255
Split into smaller subnets/19
/8 (2)/9 (4)/10 (8)/11 (16)/12 (32)/13 (64)/14 (128)/15 (256)/16 (512)/17 (1,024)/18 (2,048)/19 (4,096)

134.0.0.0/7 makes 4,096 subnets of /19; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
1134.0.0.0/19134.0.0.1 to 134.0.31.254134.0.31.2558,190
2134.0.32.0/19134.0.32.1 to 134.0.63.254134.0.63.2558,190
3134.0.64.0/19134.0.64.1 to 134.0.95.254134.0.95.2558,190
4134.0.96.0/19134.0.96.1 to 134.0.127.254134.0.127.2558,190
5134.0.128.0/19134.0.128.1 to 134.0.159.254134.0.159.2558,190
6134.0.160.0/19134.0.160.1 to 134.0.191.254134.0.191.2558,190
7134.0.192.0/19134.0.192.1 to 134.0.223.254134.0.223.2558,190
8134.0.224.0/19134.0.224.1 to 134.0.255.254134.0.255.2558,190
9134.1.0.0/19134.1.0.1 to 134.1.31.254134.1.31.2558,190
10134.1.32.0/19134.1.32.1 to 134.1.63.254134.1.63.2558,190
11134.1.64.0/19134.1.64.1 to 134.1.95.254134.1.95.2558,190
12134.1.96.0/19134.1.96.1 to 134.1.127.254134.1.127.2558,190
13134.1.128.0/19134.1.128.1 to 134.1.159.254134.1.159.2558,190
14134.1.160.0/19134.1.160.1 to 134.1.191.254134.1.191.2558,190
15134.1.192.0/19134.1.192.1 to 134.1.223.254134.1.223.2558,190
16134.1.224.0/19134.1.224.1 to 134.1.255.254134.1.255.2558,190
17134.2.0.0/19134.2.0.1 to 134.2.31.254134.2.31.2558,190
18134.2.32.0/19134.2.32.1 to 134.2.63.254134.2.63.2558,190
19134.2.64.0/19134.2.64.1 to 134.2.95.254134.2.95.2558,190
20134.2.96.0/19134.2.96.1 to 134.2.127.254134.2.127.2558,190
21134.2.128.0/19134.2.128.1 to 134.2.159.254134.2.159.2558,190
22134.2.160.0/19134.2.160.1 to 134.2.191.254134.2.191.2558,190
23134.2.192.0/19134.2.192.1 to 134.2.223.254134.2.223.2558,190
24134.2.224.0/19134.2.224.1 to 134.2.255.254134.2.255.2558,190
25134.3.0.0/19134.3.0.1 to 134.3.31.254134.3.31.2558,190
26134.3.32.0/19134.3.32.1 to 134.3.63.254134.3.63.2558,190
27134.3.64.0/19134.3.64.1 to 134.3.95.254134.3.95.2558,190
28134.3.96.0/19134.3.96.1 to 134.3.127.254134.3.127.2558,190
29134.3.128.0/19134.3.128.1 to 134.3.159.254134.3.159.2558,190
30134.3.160.0/19134.3.160.1 to 134.3.191.254134.3.191.2558,190
31134.3.192.0/19134.3.192.1 to 134.3.223.254134.3.223.2558,190
32134.3.224.0/19134.3.224.1 to 134.3.255.254134.3.255.2558,190
33134.4.0.0/19134.4.0.1 to 134.4.31.254134.4.31.2558,190
34134.4.32.0/19134.4.32.1 to 134.4.63.254134.4.63.2558,190
35134.4.64.0/19134.4.64.1 to 134.4.95.254134.4.95.2558,190
36134.4.96.0/19134.4.96.1 to 134.4.127.254134.4.127.2558,190
37134.4.128.0/19134.4.128.1 to 134.4.159.254134.4.159.2558,190
38134.4.160.0/19134.4.160.1 to 134.4.191.254134.4.191.2558,190
39134.4.192.0/19134.4.192.1 to 134.4.223.254134.4.223.2558,190
40134.4.224.0/19134.4.224.1 to 134.4.255.254134.4.255.2558,190
41134.5.0.0/19134.5.0.1 to 134.5.31.254134.5.31.2558,190
42134.5.32.0/19134.5.32.1 to 134.5.63.254134.5.63.2558,190
43134.5.64.0/19134.5.64.1 to 134.5.95.254134.5.95.2558,190
44134.5.96.0/19134.5.96.1 to 134.5.127.254134.5.127.2558,190
45134.5.128.0/19134.5.128.1 to 134.5.159.254134.5.159.2558,190
46134.5.160.0/19134.5.160.1 to 134.5.191.254134.5.191.2558,190
47134.5.192.0/19134.5.192.1 to 134.5.223.254134.5.223.2558,190
48134.5.224.0/19134.5.224.1 to 134.5.255.254134.5.255.2558,190
49134.6.0.0/19134.6.0.1 to 134.6.31.254134.6.31.2558,190
50134.6.32.0/19134.6.32.1 to 134.6.63.254134.6.63.2558,190
51134.6.64.0/19134.6.64.1 to 134.6.95.254134.6.95.2558,190
52134.6.96.0/19134.6.96.1 to 134.6.127.254134.6.127.2558,190
53134.6.128.0/19134.6.128.1 to 134.6.159.254134.6.159.2558,190
54134.6.160.0/19134.6.160.1 to 134.6.191.254134.6.191.2558,190
55134.6.192.0/19134.6.192.1 to 134.6.223.254134.6.223.2558,190
56134.6.224.0/19134.6.224.1 to 134.6.255.254134.6.255.2558,190
57134.7.0.0/19134.7.0.1 to 134.7.31.254134.7.31.2558,190
58134.7.32.0/19134.7.32.1 to 134.7.63.254134.7.63.2558,190
59134.7.64.0/19134.7.64.1 to 134.7.95.254134.7.95.2558,190
60134.7.96.0/19134.7.96.1 to 134.7.127.254134.7.127.2558,190
61134.7.128.0/19134.7.128.1 to 134.7.159.254134.7.159.2558,190
62134.7.160.0/19134.7.160.1 to 134.7.191.254134.7.191.2558,190
63134.7.192.0/19134.7.192.1 to 134.7.223.254134.7.223.2558,190
64134.7.224.0/19134.7.224.1 to 134.7.255.254134.7.255.2558,190
65134.8.0.0/19134.8.0.1 to 134.8.31.254134.8.31.2558,190
66134.8.32.0/19134.8.32.1 to 134.8.63.254134.8.63.2558,190
67134.8.64.0/19134.8.64.1 to 134.8.95.254134.8.95.2558,190
68134.8.96.0/19134.8.96.1 to 134.8.127.254134.8.127.2558,190
69134.8.128.0/19134.8.128.1 to 134.8.159.254134.8.159.2558,190
70134.8.160.0/19134.8.160.1 to 134.8.191.254134.8.191.2558,190
71134.8.192.0/19134.8.192.1 to 134.8.223.254134.8.223.2558,190
72134.8.224.0/19134.8.224.1 to 134.8.255.254134.8.255.2558,190
73134.9.0.0/19134.9.0.1 to 134.9.31.254134.9.31.2558,190
74134.9.32.0/19134.9.32.1 to 134.9.63.254134.9.63.2558,190
75134.9.64.0/19134.9.64.1 to 134.9.95.254134.9.95.2558,190
76134.9.96.0/19134.9.96.1 to 134.9.127.254134.9.127.2558,190
77134.9.128.0/19134.9.128.1 to 134.9.159.254134.9.159.2558,190
78134.9.160.0/19134.9.160.1 to 134.9.191.254134.9.191.2558,190
79134.9.192.0/19134.9.192.1 to 134.9.223.254134.9.223.2558,190
80134.9.224.0/19134.9.224.1 to 134.9.255.254134.9.255.2558,190
81134.10.0.0/19134.10.0.1 to 134.10.31.254134.10.31.2558,190
82134.10.32.0/19134.10.32.1 to 134.10.63.254134.10.63.2558,190
83134.10.64.0/19134.10.64.1 to 134.10.95.254134.10.95.2558,190
84134.10.96.0/19134.10.96.1 to 134.10.127.254134.10.127.2558,190
85134.10.128.0/19134.10.128.1 to 134.10.159.254134.10.159.2558,190
86134.10.160.0/19134.10.160.1 to 134.10.191.254134.10.191.2558,190
87134.10.192.0/19134.10.192.1 to 134.10.223.254134.10.223.2558,190
88134.10.224.0/19134.10.224.1 to 134.10.255.254134.10.255.2558,190
89134.11.0.0/19134.11.0.1 to 134.11.31.254134.11.31.2558,190
90134.11.32.0/19134.11.32.1 to 134.11.63.254134.11.63.2558,190
91134.11.64.0/19134.11.64.1 to 134.11.95.254134.11.95.2558,190
92134.11.96.0/19134.11.96.1 to 134.11.127.254134.11.127.2558,190
93134.11.128.0/19134.11.128.1 to 134.11.159.254134.11.159.2558,190
94134.11.160.0/19134.11.160.1 to 134.11.191.254134.11.191.2558,190
95134.11.192.0/19134.11.192.1 to 134.11.223.254134.11.223.2558,190
96134.11.224.0/19134.11.224.1 to 134.11.255.254134.11.255.2558,190
97134.12.0.0/19134.12.0.1 to 134.12.31.254134.12.31.2558,190
98134.12.32.0/19134.12.32.1 to 134.12.63.254134.12.63.2558,190
99134.12.64.0/19134.12.64.1 to 134.12.95.254134.12.95.2558,190
100134.12.96.0/19134.12.96.1 to 134.12.127.254134.12.127.2558,190
101134.12.128.0/19134.12.128.1 to 134.12.159.254134.12.159.2558,190
102134.12.160.0/19134.12.160.1 to 134.12.191.254134.12.191.2558,190
103134.12.192.0/19134.12.192.1 to 134.12.223.254134.12.223.2558,190
104134.12.224.0/19134.12.224.1 to 134.12.255.254134.12.255.2558,190
105134.13.0.0/19134.13.0.1 to 134.13.31.254134.13.31.2558,190
106134.13.32.0/19134.13.32.1 to 134.13.63.254134.13.63.2558,190
107134.13.64.0/19134.13.64.1 to 134.13.95.254134.13.95.2558,190
108134.13.96.0/19134.13.96.1 to 134.13.127.254134.13.127.2558,190
109134.13.128.0/19134.13.128.1 to 134.13.159.254134.13.159.2558,190
110134.13.160.0/19134.13.160.1 to 134.13.191.254134.13.191.2558,190
111134.13.192.0/19134.13.192.1 to 134.13.223.254134.13.223.2558,190
112134.13.224.0/19134.13.224.1 to 134.13.255.254134.13.255.2558,190
113134.14.0.0/19134.14.0.1 to 134.14.31.254134.14.31.2558,190
114134.14.32.0/19134.14.32.1 to 134.14.63.254134.14.63.2558,190
115134.14.64.0/19134.14.64.1 to 134.14.95.254134.14.95.2558,190
116134.14.96.0/19134.14.96.1 to 134.14.127.254134.14.127.2558,190
117134.14.128.0/19134.14.128.1 to 134.14.159.254134.14.159.2558,190
118134.14.160.0/19134.14.160.1 to 134.14.191.254134.14.191.2558,190
119134.14.192.0/19134.14.192.1 to 134.14.223.254134.14.223.2558,190
120134.14.224.0/19134.14.224.1 to 134.14.255.254134.14.255.2558,190
121134.15.0.0/19134.15.0.1 to 134.15.31.254134.15.31.2558,190
122134.15.32.0/19134.15.32.1 to 134.15.63.254134.15.63.2558,190
123134.15.64.0/19134.15.64.1 to 134.15.95.254134.15.95.2558,190
124134.15.96.0/19134.15.96.1 to 134.15.127.254134.15.127.2558,190
125134.15.128.0/19134.15.128.1 to 134.15.159.254134.15.159.2558,190
126134.15.160.0/19134.15.160.1 to 134.15.191.254134.15.191.2558,190
127134.15.192.0/19134.15.192.1 to 134.15.223.254134.15.223.2558,190
128134.15.224.0/19134.15.224.1 to 134.15.255.254134.15.255.2558,190
129134.16.0.0/19134.16.0.1 to 134.16.31.254134.16.31.2558,190
130134.16.32.0/19134.16.32.1 to 134.16.63.254134.16.63.2558,190
131134.16.64.0/19134.16.64.1 to 134.16.95.254134.16.95.2558,190
132134.16.96.0/19134.16.96.1 to 134.16.127.254134.16.127.2558,190
133134.16.128.0/19134.16.128.1 to 134.16.159.254134.16.159.2558,190
134134.16.160.0/19134.16.160.1 to 134.16.191.254134.16.191.2558,190
135134.16.192.0/19134.16.192.1 to 134.16.223.254134.16.223.2558,190
136134.16.224.0/19134.16.224.1 to 134.16.255.254134.16.255.2558,190
137134.17.0.0/19134.17.0.1 to 134.17.31.254134.17.31.2558,190
138134.17.32.0/19134.17.32.1 to 134.17.63.254134.17.63.2558,190
139134.17.64.0/19134.17.64.1 to 134.17.95.254134.17.95.2558,190
140134.17.96.0/19134.17.96.1 to 134.17.127.254134.17.127.2558,190
141134.17.128.0/19134.17.128.1 to 134.17.159.254134.17.159.2558,190
142134.17.160.0/19134.17.160.1 to 134.17.191.254134.17.191.2558,190
143134.17.192.0/19134.17.192.1 to 134.17.223.254134.17.223.2558,190
144134.17.224.0/19134.17.224.1 to 134.17.255.254134.17.255.2558,190
145134.18.0.0/19134.18.0.1 to 134.18.31.254134.18.31.2558,190
146134.18.32.0/19134.18.32.1 to 134.18.63.254134.18.63.2558,190
147134.18.64.0/19134.18.64.1 to 134.18.95.254134.18.95.2558,190
148134.18.96.0/19134.18.96.1 to 134.18.127.254134.18.127.2558,190
149134.18.128.0/19134.18.128.1 to 134.18.159.254134.18.159.2558,190
150134.18.160.0/19134.18.160.1 to 134.18.191.254134.18.191.2558,190
151134.18.192.0/19134.18.192.1 to 134.18.223.254134.18.223.2558,190
152134.18.224.0/19134.18.224.1 to 134.18.255.254134.18.255.2558,190
153134.19.0.0/19134.19.0.1 to 134.19.31.254134.19.31.2558,190
154134.19.32.0/19134.19.32.1 to 134.19.63.254134.19.63.2558,190
155134.19.64.0/19134.19.64.1 to 134.19.95.254134.19.95.2558,190
156134.19.96.0/19134.19.96.1 to 134.19.127.254134.19.127.2558,190
157134.19.128.0/19134.19.128.1 to 134.19.159.254134.19.159.2558,190
158134.19.160.0/19134.19.160.1 to 134.19.191.254134.19.191.2558,190
159134.19.192.0/19134.19.192.1 to 134.19.223.254134.19.223.2558,190
160134.19.224.0/19134.19.224.1 to 134.19.255.254134.19.255.2558,190
161134.20.0.0/19134.20.0.1 to 134.20.31.254134.20.31.2558,190
162134.20.32.0/19134.20.32.1 to 134.20.63.254134.20.63.2558,190
163134.20.64.0/19134.20.64.1 to 134.20.95.254134.20.95.2558,190
164134.20.96.0/19134.20.96.1 to 134.20.127.254134.20.127.2558,190
165134.20.128.0/19134.20.128.1 to 134.20.159.254134.20.159.2558,190
166134.20.160.0/19134.20.160.1 to 134.20.191.254134.20.191.2558,190
167134.20.192.0/19134.20.192.1 to 134.20.223.254134.20.223.2558,190
168134.20.224.0/19134.20.224.1 to 134.20.255.254134.20.255.2558,190
169134.21.0.0/19134.21.0.1 to 134.21.31.254134.21.31.2558,190
170134.21.32.0/19134.21.32.1 to 134.21.63.254134.21.63.2558,190
171134.21.64.0/19134.21.64.1 to 134.21.95.254134.21.95.2558,190
172134.21.96.0/19134.21.96.1 to 134.21.127.254134.21.127.2558,190
173134.21.128.0/19134.21.128.1 to 134.21.159.254134.21.159.2558,190
174134.21.160.0/19134.21.160.1 to 134.21.191.254134.21.191.2558,190
175134.21.192.0/19134.21.192.1 to 134.21.223.254134.21.223.2558,190
176134.21.224.0/19134.21.224.1 to 134.21.255.254134.21.255.2558,190
177134.22.0.0/19134.22.0.1 to 134.22.31.254134.22.31.2558,190
178134.22.32.0/19134.22.32.1 to 134.22.63.254134.22.63.2558,190
179134.22.64.0/19134.22.64.1 to 134.22.95.254134.22.95.2558,190
180134.22.96.0/19134.22.96.1 to 134.22.127.254134.22.127.2558,190
181134.22.128.0/19134.22.128.1 to 134.22.159.254134.22.159.2558,190
182134.22.160.0/19134.22.160.1 to 134.22.191.254134.22.191.2558,190
183134.22.192.0/19134.22.192.1 to 134.22.223.254134.22.223.2558,190
184134.22.224.0/19134.22.224.1 to 134.22.255.254134.22.255.2558,190
185134.23.0.0/19134.23.0.1 to 134.23.31.254134.23.31.2558,190
186134.23.32.0/19134.23.32.1 to 134.23.63.254134.23.63.2558,190
187134.23.64.0/19134.23.64.1 to 134.23.95.254134.23.95.2558,190
188134.23.96.0/19134.23.96.1 to 134.23.127.254134.23.127.2558,190
189134.23.128.0/19134.23.128.1 to 134.23.159.254134.23.159.2558,190
190134.23.160.0/19134.23.160.1 to 134.23.191.254134.23.191.2558,190
191134.23.192.0/19134.23.192.1 to 134.23.223.254134.23.223.2558,190
192134.23.224.0/19134.23.224.1 to 134.23.255.254134.23.255.2558,190
193134.24.0.0/19134.24.0.1 to 134.24.31.254134.24.31.2558,190
194134.24.32.0/19134.24.32.1 to 134.24.63.254134.24.63.2558,190
195134.24.64.0/19134.24.64.1 to 134.24.95.254134.24.95.2558,190
196134.24.96.0/19134.24.96.1 to 134.24.127.254134.24.127.2558,190
197134.24.128.0/19134.24.128.1 to 134.24.159.254134.24.159.2558,190
198134.24.160.0/19134.24.160.1 to 134.24.191.254134.24.191.2558,190
199134.24.192.0/19134.24.192.1 to 134.24.223.254134.24.223.2558,190
200134.24.224.0/19134.24.224.1 to 134.24.255.254134.24.255.2558,190
201134.25.0.0/19134.25.0.1 to 134.25.31.254134.25.31.2558,190
202134.25.32.0/19134.25.32.1 to 134.25.63.254134.25.63.2558,190
203134.25.64.0/19134.25.64.1 to 134.25.95.254134.25.95.2558,190
204134.25.96.0/19134.25.96.1 to 134.25.127.254134.25.127.2558,190
205134.25.128.0/19134.25.128.1 to 134.25.159.254134.25.159.2558,190
206134.25.160.0/19134.25.160.1 to 134.25.191.254134.25.191.2558,190
207134.25.192.0/19134.25.192.1 to 134.25.223.254134.25.223.2558,190
208134.25.224.0/19134.25.224.1 to 134.25.255.254134.25.255.2558,190
209134.26.0.0/19134.26.0.1 to 134.26.31.254134.26.31.2558,190
210134.26.32.0/19134.26.32.1 to 134.26.63.254134.26.63.2558,190
211134.26.64.0/19134.26.64.1 to 134.26.95.254134.26.95.2558,190
212134.26.96.0/19134.26.96.1 to 134.26.127.254134.26.127.2558,190
213134.26.128.0/19134.26.128.1 to 134.26.159.254134.26.159.2558,190
214134.26.160.0/19134.26.160.1 to 134.26.191.254134.26.191.2558,190
215134.26.192.0/19134.26.192.1 to 134.26.223.254134.26.223.2558,190
216134.26.224.0/19134.26.224.1 to 134.26.255.254134.26.255.2558,190
217134.27.0.0/19134.27.0.1 to 134.27.31.254134.27.31.2558,190
218134.27.32.0/19134.27.32.1 to 134.27.63.254134.27.63.2558,190
219134.27.64.0/19134.27.64.1 to 134.27.95.254134.27.95.2558,190
220134.27.96.0/19134.27.96.1 to 134.27.127.254134.27.127.2558,190
221134.27.128.0/19134.27.128.1 to 134.27.159.254134.27.159.2558,190
222134.27.160.0/19134.27.160.1 to 134.27.191.254134.27.191.2558,190
223134.27.192.0/19134.27.192.1 to 134.27.223.254134.27.223.2558,190
224134.27.224.0/19134.27.224.1 to 134.27.255.254134.27.255.2558,190
225134.28.0.0/19134.28.0.1 to 134.28.31.254134.28.31.2558,190
226134.28.32.0/19134.28.32.1 to 134.28.63.254134.28.63.2558,190
227134.28.64.0/19134.28.64.1 to 134.28.95.254134.28.95.2558,190
228134.28.96.0/19134.28.96.1 to 134.28.127.254134.28.127.2558,190
229134.28.128.0/19134.28.128.1 to 134.28.159.254134.28.159.2558,190
230134.28.160.0/19134.28.160.1 to 134.28.191.254134.28.191.2558,190
231134.28.192.0/19134.28.192.1 to 134.28.223.254134.28.223.2558,190
232134.28.224.0/19134.28.224.1 to 134.28.255.254134.28.255.2558,190
233134.29.0.0/19134.29.0.1 to 134.29.31.254134.29.31.2558,190
234134.29.32.0/19134.29.32.1 to 134.29.63.254134.29.63.2558,190
235134.29.64.0/19134.29.64.1 to 134.29.95.254134.29.95.2558,190
236134.29.96.0/19134.29.96.1 to 134.29.127.254134.29.127.2558,190
237134.29.128.0/19134.29.128.1 to 134.29.159.254134.29.159.2558,190
238134.29.160.0/19134.29.160.1 to 134.29.191.254134.29.191.2558,190
239134.29.192.0/19134.29.192.1 to 134.29.223.254134.29.223.2558,190
240134.29.224.0/19134.29.224.1 to 134.29.255.254134.29.255.2558,190
241134.30.0.0/19134.30.0.1 to 134.30.31.254134.30.31.2558,190
242134.30.32.0/19134.30.32.1 to 134.30.63.254134.30.63.2558,190
243134.30.64.0/19134.30.64.1 to 134.30.95.254134.30.95.2558,190
244134.30.96.0/19134.30.96.1 to 134.30.127.254134.30.127.2558,190
245134.30.128.0/19134.30.128.1 to 134.30.159.254134.30.159.2558,190
246134.30.160.0/19134.30.160.1 to 134.30.191.254134.30.191.2558,190
247134.30.192.0/19134.30.192.1 to 134.30.223.254134.30.223.2558,190
248134.30.224.0/19134.30.224.1 to 134.30.255.254134.30.255.2558,190
249134.31.0.0/19134.31.0.1 to 134.31.31.254134.31.31.2558,190
250134.31.32.0/19134.31.32.1 to 134.31.63.254134.31.63.2558,190
251134.31.64.0/19134.31.64.1 to 134.31.95.254134.31.95.2558,190
252134.31.96.0/19134.31.96.1 to 134.31.127.254134.31.127.2558,190
253134.31.128.0/19134.31.128.1 to 134.31.159.254134.31.159.2558,190
254134.31.160.0/19134.31.160.1 to 134.31.191.254134.31.191.2558,190
255134.31.192.0/19134.31.192.1 to 134.31.223.254134.31.223.2558,190
256134.31.224.0/19134.31.224.1 to 134.31.255.254134.31.255.2558,190

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.