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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.

Network224.0.0.0/7
Usable hosts33,554,430
Subnet mask254.0.0.0
Addresses33,554,432
Network address
224.0.0.0
Broadcast address
225.255.255.255
First usable
224.0.0.1
Last usable
225.255.255.254
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
Multicast 224.0.0.0/4
One-to-many traffic, such as IPTV and routing protocols
Old class
D (multicast)
As numbers
Hex E0000000 · Integer 3758096384 to 3791650815
Reverse DNS zones
224.in-addr.arpa
225.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
Address11100000.00000000.00000000.00000000224.0.0.0
Subnet mask11111110.00000000.00000000.00000000254.0.0.0
Network11100000.00000000.00000000.00000000224.0.0.0
Broadcast11100001.11111111.11111111.11111111225.255.255.255
Split into smaller subnets/18
/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)

224.0.0.0/7 makes 2,048 subnets of /18; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
1224.0.0.0/18224.0.0.1 to 224.0.63.254224.0.63.25516,382
2224.0.64.0/18224.0.64.1 to 224.0.127.254224.0.127.25516,382
3224.0.128.0/18224.0.128.1 to 224.0.191.254224.0.191.25516,382
4224.0.192.0/18224.0.192.1 to 224.0.255.254224.0.255.25516,382
5224.1.0.0/18224.1.0.1 to 224.1.63.254224.1.63.25516,382
6224.1.64.0/18224.1.64.1 to 224.1.127.254224.1.127.25516,382
7224.1.128.0/18224.1.128.1 to 224.1.191.254224.1.191.25516,382
8224.1.192.0/18224.1.192.1 to 224.1.255.254224.1.255.25516,382
9224.2.0.0/18224.2.0.1 to 224.2.63.254224.2.63.25516,382
10224.2.64.0/18224.2.64.1 to 224.2.127.254224.2.127.25516,382
11224.2.128.0/18224.2.128.1 to 224.2.191.254224.2.191.25516,382
12224.2.192.0/18224.2.192.1 to 224.2.255.254224.2.255.25516,382
13224.3.0.0/18224.3.0.1 to 224.3.63.254224.3.63.25516,382
14224.3.64.0/18224.3.64.1 to 224.3.127.254224.3.127.25516,382
15224.3.128.0/18224.3.128.1 to 224.3.191.254224.3.191.25516,382
16224.3.192.0/18224.3.192.1 to 224.3.255.254224.3.255.25516,382
17224.4.0.0/18224.4.0.1 to 224.4.63.254224.4.63.25516,382
18224.4.64.0/18224.4.64.1 to 224.4.127.254224.4.127.25516,382
19224.4.128.0/18224.4.128.1 to 224.4.191.254224.4.191.25516,382
20224.4.192.0/18224.4.192.1 to 224.4.255.254224.4.255.25516,382
21224.5.0.0/18224.5.0.1 to 224.5.63.254224.5.63.25516,382
22224.5.64.0/18224.5.64.1 to 224.5.127.254224.5.127.25516,382
23224.5.128.0/18224.5.128.1 to 224.5.191.254224.5.191.25516,382
24224.5.192.0/18224.5.192.1 to 224.5.255.254224.5.255.25516,382
25224.6.0.0/18224.6.0.1 to 224.6.63.254224.6.63.25516,382
26224.6.64.0/18224.6.64.1 to 224.6.127.254224.6.127.25516,382
27224.6.128.0/18224.6.128.1 to 224.6.191.254224.6.191.25516,382
28224.6.192.0/18224.6.192.1 to 224.6.255.254224.6.255.25516,382
29224.7.0.0/18224.7.0.1 to 224.7.63.254224.7.63.25516,382
30224.7.64.0/18224.7.64.1 to 224.7.127.254224.7.127.25516,382
31224.7.128.0/18224.7.128.1 to 224.7.191.254224.7.191.25516,382
32224.7.192.0/18224.7.192.1 to 224.7.255.254224.7.255.25516,382
33224.8.0.0/18224.8.0.1 to 224.8.63.254224.8.63.25516,382
34224.8.64.0/18224.8.64.1 to 224.8.127.254224.8.127.25516,382
35224.8.128.0/18224.8.128.1 to 224.8.191.254224.8.191.25516,382
36224.8.192.0/18224.8.192.1 to 224.8.255.254224.8.255.25516,382
37224.9.0.0/18224.9.0.1 to 224.9.63.254224.9.63.25516,382
38224.9.64.0/18224.9.64.1 to 224.9.127.254224.9.127.25516,382
39224.9.128.0/18224.9.128.1 to 224.9.191.254224.9.191.25516,382
40224.9.192.0/18224.9.192.1 to 224.9.255.254224.9.255.25516,382
41224.10.0.0/18224.10.0.1 to 224.10.63.254224.10.63.25516,382
42224.10.64.0/18224.10.64.1 to 224.10.127.254224.10.127.25516,382
43224.10.128.0/18224.10.128.1 to 224.10.191.254224.10.191.25516,382
44224.10.192.0/18224.10.192.1 to 224.10.255.254224.10.255.25516,382
45224.11.0.0/18224.11.0.1 to 224.11.63.254224.11.63.25516,382
46224.11.64.0/18224.11.64.1 to 224.11.127.254224.11.127.25516,382
47224.11.128.0/18224.11.128.1 to 224.11.191.254224.11.191.25516,382
48224.11.192.0/18224.11.192.1 to 224.11.255.254224.11.255.25516,382
49224.12.0.0/18224.12.0.1 to 224.12.63.254224.12.63.25516,382
50224.12.64.0/18224.12.64.1 to 224.12.127.254224.12.127.25516,382
51224.12.128.0/18224.12.128.1 to 224.12.191.254224.12.191.25516,382
52224.12.192.0/18224.12.192.1 to 224.12.255.254224.12.255.25516,382
53224.13.0.0/18224.13.0.1 to 224.13.63.254224.13.63.25516,382
54224.13.64.0/18224.13.64.1 to 224.13.127.254224.13.127.25516,382
55224.13.128.0/18224.13.128.1 to 224.13.191.254224.13.191.25516,382
56224.13.192.0/18224.13.192.1 to 224.13.255.254224.13.255.25516,382
57224.14.0.0/18224.14.0.1 to 224.14.63.254224.14.63.25516,382
58224.14.64.0/18224.14.64.1 to 224.14.127.254224.14.127.25516,382
59224.14.128.0/18224.14.128.1 to 224.14.191.254224.14.191.25516,382
60224.14.192.0/18224.14.192.1 to 224.14.255.254224.14.255.25516,382
61224.15.0.0/18224.15.0.1 to 224.15.63.254224.15.63.25516,382
62224.15.64.0/18224.15.64.1 to 224.15.127.254224.15.127.25516,382
63224.15.128.0/18224.15.128.1 to 224.15.191.254224.15.191.25516,382
64224.15.192.0/18224.15.192.1 to 224.15.255.254224.15.255.25516,382
65224.16.0.0/18224.16.0.1 to 224.16.63.254224.16.63.25516,382
66224.16.64.0/18224.16.64.1 to 224.16.127.254224.16.127.25516,382
67224.16.128.0/18224.16.128.1 to 224.16.191.254224.16.191.25516,382
68224.16.192.0/18224.16.192.1 to 224.16.255.254224.16.255.25516,382
69224.17.0.0/18224.17.0.1 to 224.17.63.254224.17.63.25516,382
70224.17.64.0/18224.17.64.1 to 224.17.127.254224.17.127.25516,382
71224.17.128.0/18224.17.128.1 to 224.17.191.254224.17.191.25516,382
72224.17.192.0/18224.17.192.1 to 224.17.255.254224.17.255.25516,382
73224.18.0.0/18224.18.0.1 to 224.18.63.254224.18.63.25516,382
74224.18.64.0/18224.18.64.1 to 224.18.127.254224.18.127.25516,382
75224.18.128.0/18224.18.128.1 to 224.18.191.254224.18.191.25516,382
76224.18.192.0/18224.18.192.1 to 224.18.255.254224.18.255.25516,382
77224.19.0.0/18224.19.0.1 to 224.19.63.254224.19.63.25516,382
78224.19.64.0/18224.19.64.1 to 224.19.127.254224.19.127.25516,382
79224.19.128.0/18224.19.128.1 to 224.19.191.254224.19.191.25516,382
80224.19.192.0/18224.19.192.1 to 224.19.255.254224.19.255.25516,382
81224.20.0.0/18224.20.0.1 to 224.20.63.254224.20.63.25516,382
82224.20.64.0/18224.20.64.1 to 224.20.127.254224.20.127.25516,382
83224.20.128.0/18224.20.128.1 to 224.20.191.254224.20.191.25516,382
84224.20.192.0/18224.20.192.1 to 224.20.255.254224.20.255.25516,382
85224.21.0.0/18224.21.0.1 to 224.21.63.254224.21.63.25516,382
86224.21.64.0/18224.21.64.1 to 224.21.127.254224.21.127.25516,382
87224.21.128.0/18224.21.128.1 to 224.21.191.254224.21.191.25516,382
88224.21.192.0/18224.21.192.1 to 224.21.255.254224.21.255.25516,382
89224.22.0.0/18224.22.0.1 to 224.22.63.254224.22.63.25516,382
90224.22.64.0/18224.22.64.1 to 224.22.127.254224.22.127.25516,382
91224.22.128.0/18224.22.128.1 to 224.22.191.254224.22.191.25516,382
92224.22.192.0/18224.22.192.1 to 224.22.255.254224.22.255.25516,382
93224.23.0.0/18224.23.0.1 to 224.23.63.254224.23.63.25516,382
94224.23.64.0/18224.23.64.1 to 224.23.127.254224.23.127.25516,382
95224.23.128.0/18224.23.128.1 to 224.23.191.254224.23.191.25516,382
96224.23.192.0/18224.23.192.1 to 224.23.255.254224.23.255.25516,382
97224.24.0.0/18224.24.0.1 to 224.24.63.254224.24.63.25516,382
98224.24.64.0/18224.24.64.1 to 224.24.127.254224.24.127.25516,382
99224.24.128.0/18224.24.128.1 to 224.24.191.254224.24.191.25516,382
100224.24.192.0/18224.24.192.1 to 224.24.255.254224.24.255.25516,382
101224.25.0.0/18224.25.0.1 to 224.25.63.254224.25.63.25516,382
102224.25.64.0/18224.25.64.1 to 224.25.127.254224.25.127.25516,382
103224.25.128.0/18224.25.128.1 to 224.25.191.254224.25.191.25516,382
104224.25.192.0/18224.25.192.1 to 224.25.255.254224.25.255.25516,382
105224.26.0.0/18224.26.0.1 to 224.26.63.254224.26.63.25516,382
106224.26.64.0/18224.26.64.1 to 224.26.127.254224.26.127.25516,382
107224.26.128.0/18224.26.128.1 to 224.26.191.254224.26.191.25516,382
108224.26.192.0/18224.26.192.1 to 224.26.255.254224.26.255.25516,382
109224.27.0.0/18224.27.0.1 to 224.27.63.254224.27.63.25516,382
110224.27.64.0/18224.27.64.1 to 224.27.127.254224.27.127.25516,382
111224.27.128.0/18224.27.128.1 to 224.27.191.254224.27.191.25516,382
112224.27.192.0/18224.27.192.1 to 224.27.255.254224.27.255.25516,382
113224.28.0.0/18224.28.0.1 to 224.28.63.254224.28.63.25516,382
114224.28.64.0/18224.28.64.1 to 224.28.127.254224.28.127.25516,382
115224.28.128.0/18224.28.128.1 to 224.28.191.254224.28.191.25516,382
116224.28.192.0/18224.28.192.1 to 224.28.255.254224.28.255.25516,382
117224.29.0.0/18224.29.0.1 to 224.29.63.254224.29.63.25516,382
118224.29.64.0/18224.29.64.1 to 224.29.127.254224.29.127.25516,382
119224.29.128.0/18224.29.128.1 to 224.29.191.254224.29.191.25516,382
120224.29.192.0/18224.29.192.1 to 224.29.255.254224.29.255.25516,382
121224.30.0.0/18224.30.0.1 to 224.30.63.254224.30.63.25516,382
122224.30.64.0/18224.30.64.1 to 224.30.127.254224.30.127.25516,382
123224.30.128.0/18224.30.128.1 to 224.30.191.254224.30.191.25516,382
124224.30.192.0/18224.30.192.1 to 224.30.255.254224.30.255.25516,382
125224.31.0.0/18224.31.0.1 to 224.31.63.254224.31.63.25516,382
126224.31.64.0/18224.31.64.1 to 224.31.127.254224.31.127.25516,382
127224.31.128.0/18224.31.128.1 to 224.31.191.254224.31.191.25516,382
128224.31.192.0/18224.31.192.1 to 224.31.255.254224.31.255.25516,382
129224.32.0.0/18224.32.0.1 to 224.32.63.254224.32.63.25516,382
130224.32.64.0/18224.32.64.1 to 224.32.127.254224.32.127.25516,382
131224.32.128.0/18224.32.128.1 to 224.32.191.254224.32.191.25516,382
132224.32.192.0/18224.32.192.1 to 224.32.255.254224.32.255.25516,382
133224.33.0.0/18224.33.0.1 to 224.33.63.254224.33.63.25516,382
134224.33.64.0/18224.33.64.1 to 224.33.127.254224.33.127.25516,382
135224.33.128.0/18224.33.128.1 to 224.33.191.254224.33.191.25516,382
136224.33.192.0/18224.33.192.1 to 224.33.255.254224.33.255.25516,382
137224.34.0.0/18224.34.0.1 to 224.34.63.254224.34.63.25516,382
138224.34.64.0/18224.34.64.1 to 224.34.127.254224.34.127.25516,382
139224.34.128.0/18224.34.128.1 to 224.34.191.254224.34.191.25516,382
140224.34.192.0/18224.34.192.1 to 224.34.255.254224.34.255.25516,382
141224.35.0.0/18224.35.0.1 to 224.35.63.254224.35.63.25516,382
142224.35.64.0/18224.35.64.1 to 224.35.127.254224.35.127.25516,382
143224.35.128.0/18224.35.128.1 to 224.35.191.254224.35.191.25516,382
144224.35.192.0/18224.35.192.1 to 224.35.255.254224.35.255.25516,382
145224.36.0.0/18224.36.0.1 to 224.36.63.254224.36.63.25516,382
146224.36.64.0/18224.36.64.1 to 224.36.127.254224.36.127.25516,382
147224.36.128.0/18224.36.128.1 to 224.36.191.254224.36.191.25516,382
148224.36.192.0/18224.36.192.1 to 224.36.255.254224.36.255.25516,382
149224.37.0.0/18224.37.0.1 to 224.37.63.254224.37.63.25516,382
150224.37.64.0/18224.37.64.1 to 224.37.127.254224.37.127.25516,382
151224.37.128.0/18224.37.128.1 to 224.37.191.254224.37.191.25516,382
152224.37.192.0/18224.37.192.1 to 224.37.255.254224.37.255.25516,382
153224.38.0.0/18224.38.0.1 to 224.38.63.254224.38.63.25516,382
154224.38.64.0/18224.38.64.1 to 224.38.127.254224.38.127.25516,382
155224.38.128.0/18224.38.128.1 to 224.38.191.254224.38.191.25516,382
156224.38.192.0/18224.38.192.1 to 224.38.255.254224.38.255.25516,382
157224.39.0.0/18224.39.0.1 to 224.39.63.254224.39.63.25516,382
158224.39.64.0/18224.39.64.1 to 224.39.127.254224.39.127.25516,382
159224.39.128.0/18224.39.128.1 to 224.39.191.254224.39.191.25516,382
160224.39.192.0/18224.39.192.1 to 224.39.255.254224.39.255.25516,382
161224.40.0.0/18224.40.0.1 to 224.40.63.254224.40.63.25516,382
162224.40.64.0/18224.40.64.1 to 224.40.127.254224.40.127.25516,382
163224.40.128.0/18224.40.128.1 to 224.40.191.254224.40.191.25516,382
164224.40.192.0/18224.40.192.1 to 224.40.255.254224.40.255.25516,382
165224.41.0.0/18224.41.0.1 to 224.41.63.254224.41.63.25516,382
166224.41.64.0/18224.41.64.1 to 224.41.127.254224.41.127.25516,382
167224.41.128.0/18224.41.128.1 to 224.41.191.254224.41.191.25516,382
168224.41.192.0/18224.41.192.1 to 224.41.255.254224.41.255.25516,382
169224.42.0.0/18224.42.0.1 to 224.42.63.254224.42.63.25516,382
170224.42.64.0/18224.42.64.1 to 224.42.127.254224.42.127.25516,382
171224.42.128.0/18224.42.128.1 to 224.42.191.254224.42.191.25516,382
172224.42.192.0/18224.42.192.1 to 224.42.255.254224.42.255.25516,382
173224.43.0.0/18224.43.0.1 to 224.43.63.254224.43.63.25516,382
174224.43.64.0/18224.43.64.1 to 224.43.127.254224.43.127.25516,382
175224.43.128.0/18224.43.128.1 to 224.43.191.254224.43.191.25516,382
176224.43.192.0/18224.43.192.1 to 224.43.255.254224.43.255.25516,382
177224.44.0.0/18224.44.0.1 to 224.44.63.254224.44.63.25516,382
178224.44.64.0/18224.44.64.1 to 224.44.127.254224.44.127.25516,382
179224.44.128.0/18224.44.128.1 to 224.44.191.254224.44.191.25516,382
180224.44.192.0/18224.44.192.1 to 224.44.255.254224.44.255.25516,382
181224.45.0.0/18224.45.0.1 to 224.45.63.254224.45.63.25516,382
182224.45.64.0/18224.45.64.1 to 224.45.127.254224.45.127.25516,382
183224.45.128.0/18224.45.128.1 to 224.45.191.254224.45.191.25516,382
184224.45.192.0/18224.45.192.1 to 224.45.255.254224.45.255.25516,382
185224.46.0.0/18224.46.0.1 to 224.46.63.254224.46.63.25516,382
186224.46.64.0/18224.46.64.1 to 224.46.127.254224.46.127.25516,382
187224.46.128.0/18224.46.128.1 to 224.46.191.254224.46.191.25516,382
188224.46.192.0/18224.46.192.1 to 224.46.255.254224.46.255.25516,382
189224.47.0.0/18224.47.0.1 to 224.47.63.254224.47.63.25516,382
190224.47.64.0/18224.47.64.1 to 224.47.127.254224.47.127.25516,382
191224.47.128.0/18224.47.128.1 to 224.47.191.254224.47.191.25516,382
192224.47.192.0/18224.47.192.1 to 224.47.255.254224.47.255.25516,382
193224.48.0.0/18224.48.0.1 to 224.48.63.254224.48.63.25516,382
194224.48.64.0/18224.48.64.1 to 224.48.127.254224.48.127.25516,382
195224.48.128.0/18224.48.128.1 to 224.48.191.254224.48.191.25516,382
196224.48.192.0/18224.48.192.1 to 224.48.255.254224.48.255.25516,382
197224.49.0.0/18224.49.0.1 to 224.49.63.254224.49.63.25516,382
198224.49.64.0/18224.49.64.1 to 224.49.127.254224.49.127.25516,382
199224.49.128.0/18224.49.128.1 to 224.49.191.254224.49.191.25516,382
200224.49.192.0/18224.49.192.1 to 224.49.255.254224.49.255.25516,382
201224.50.0.0/18224.50.0.1 to 224.50.63.254224.50.63.25516,382
202224.50.64.0/18224.50.64.1 to 224.50.127.254224.50.127.25516,382
203224.50.128.0/18224.50.128.1 to 224.50.191.254224.50.191.25516,382
204224.50.192.0/18224.50.192.1 to 224.50.255.254224.50.255.25516,382
205224.51.0.0/18224.51.0.1 to 224.51.63.254224.51.63.25516,382
206224.51.64.0/18224.51.64.1 to 224.51.127.254224.51.127.25516,382
207224.51.128.0/18224.51.128.1 to 224.51.191.254224.51.191.25516,382
208224.51.192.0/18224.51.192.1 to 224.51.255.254224.51.255.25516,382
209224.52.0.0/18224.52.0.1 to 224.52.63.254224.52.63.25516,382
210224.52.64.0/18224.52.64.1 to 224.52.127.254224.52.127.25516,382
211224.52.128.0/18224.52.128.1 to 224.52.191.254224.52.191.25516,382
212224.52.192.0/18224.52.192.1 to 224.52.255.254224.52.255.25516,382
213224.53.0.0/18224.53.0.1 to 224.53.63.254224.53.63.25516,382
214224.53.64.0/18224.53.64.1 to 224.53.127.254224.53.127.25516,382
215224.53.128.0/18224.53.128.1 to 224.53.191.254224.53.191.25516,382
216224.53.192.0/18224.53.192.1 to 224.53.255.254224.53.255.25516,382
217224.54.0.0/18224.54.0.1 to 224.54.63.254224.54.63.25516,382
218224.54.64.0/18224.54.64.1 to 224.54.127.254224.54.127.25516,382
219224.54.128.0/18224.54.128.1 to 224.54.191.254224.54.191.25516,382
220224.54.192.0/18224.54.192.1 to 224.54.255.254224.54.255.25516,382
221224.55.0.0/18224.55.0.1 to 224.55.63.254224.55.63.25516,382
222224.55.64.0/18224.55.64.1 to 224.55.127.254224.55.127.25516,382
223224.55.128.0/18224.55.128.1 to 224.55.191.254224.55.191.25516,382
224224.55.192.0/18224.55.192.1 to 224.55.255.254224.55.255.25516,382
225224.56.0.0/18224.56.0.1 to 224.56.63.254224.56.63.25516,382
226224.56.64.0/18224.56.64.1 to 224.56.127.254224.56.127.25516,382
227224.56.128.0/18224.56.128.1 to 224.56.191.254224.56.191.25516,382
228224.56.192.0/18224.56.192.1 to 224.56.255.254224.56.255.25516,382
229224.57.0.0/18224.57.0.1 to 224.57.63.254224.57.63.25516,382
230224.57.64.0/18224.57.64.1 to 224.57.127.254224.57.127.25516,382
231224.57.128.0/18224.57.128.1 to 224.57.191.254224.57.191.25516,382
232224.57.192.0/18224.57.192.1 to 224.57.255.254224.57.255.25516,382
233224.58.0.0/18224.58.0.1 to 224.58.63.254224.58.63.25516,382
234224.58.64.0/18224.58.64.1 to 224.58.127.254224.58.127.25516,382
235224.58.128.0/18224.58.128.1 to 224.58.191.254224.58.191.25516,382
236224.58.192.0/18224.58.192.1 to 224.58.255.254224.58.255.25516,382
237224.59.0.0/18224.59.0.1 to 224.59.63.254224.59.63.25516,382
238224.59.64.0/18224.59.64.1 to 224.59.127.254224.59.127.25516,382
239224.59.128.0/18224.59.128.1 to 224.59.191.254224.59.191.25516,382
240224.59.192.0/18224.59.192.1 to 224.59.255.254224.59.255.25516,382
241224.60.0.0/18224.60.0.1 to 224.60.63.254224.60.63.25516,382
242224.60.64.0/18224.60.64.1 to 224.60.127.254224.60.127.25516,382
243224.60.128.0/18224.60.128.1 to 224.60.191.254224.60.191.25516,382
244224.60.192.0/18224.60.192.1 to 224.60.255.254224.60.255.25516,382
245224.61.0.0/18224.61.0.1 to 224.61.63.254224.61.63.25516,382
246224.61.64.0/18224.61.64.1 to 224.61.127.254224.61.127.25516,382
247224.61.128.0/18224.61.128.1 to 224.61.191.254224.61.191.25516,382
248224.61.192.0/18224.61.192.1 to 224.61.255.254224.61.255.25516,382
249224.62.0.0/18224.62.0.1 to 224.62.63.254224.62.63.25516,382
250224.62.64.0/18224.62.64.1 to 224.62.127.254224.62.127.25516,382
251224.62.128.0/18224.62.128.1 to 224.62.191.254224.62.191.25516,382
252224.62.192.0/18224.62.192.1 to 224.62.255.254224.62.255.25516,382
253224.63.0.0/18224.63.0.1 to 224.63.63.254224.63.63.25516,382
254224.63.64.0/18224.63.64.1 to 224.63.127.254224.63.127.25516,382
255224.63.128.0/18224.63.128.1 to 224.63.191.254224.63.191.25516,382
256224.63.192.0/18224.63.192.1 to 224.63.255.254224.63.255.25516,382

IPv4 CIDR reference (/0 to /32)

IPv4 prefix lengths
PrefixSubnet maskWildcardAddressesUsable hostsSizeTypical use
/00.0.0.0255.255.255.2554,294,967,2964,294,967,29416,777,216 × /24
/1128.0.0.0127.255.255.2552,147,483,6482,147,483,6468,388,608 × /24
/2192.0.0.063.255.255.2551,073,741,8241,073,741,8224,194,304 × /24
/3224.0.0.031.255.255.255536,870,912536,870,9102,097,152 × /24
/4240.0.0.015.255.255.255268,435,456268,435,4541,048,576 × /24
/5248.0.0.07.255.255.255134,217,728134,217,726524,288 × /24
/6252.0.0.03.255.255.25567,108,86467,108,862262,144 × /24
/7254.0.0.01.255.255.25533,554,43233,554,430131,072 × /24
/8255.0.0.00.255.255.25516,777,21616,777,21465,536 × /24Old class A; 10.0.0.0/8
/9255.128.0.00.127.255.2558,388,6088,388,60632,768 × /24
/10255.192.0.00.63.255.2554,194,3044,194,30216,384 × /24
/11255.224.0.00.31.255.2552,097,1522,097,1508,192 × /24
/12255.240.0.00.15.255.2551,048,5761,048,5744,096 × /24172.16.0.0/12
/13255.248.0.00.7.255.255524,288524,2862,048 × /24
/14255.252.0.00.3.255.255262,144262,1421,024 × /24
/15255.254.0.00.1.255.255131,072131,070512 × /24
/16255.255.0.00.0.255.25565,53665,534256 × /24Old class B; 192.168.0.0/16
/17255.255.128.00.0.127.25532,76832,766128 × /24
/18255.255.192.00.0.63.25516,38416,38264 × /24
/19255.255.224.00.0.31.2558,1928,19032 × /24
/20255.255.240.00.0.15.2554,0964,09416 × /24
/21255.255.248.00.0.7.2552,0482,0468 × /24
/22255.255.252.00.0.3.2551,0241,0224 × /24Large office or guest Wi-Fi (1,022 hosts)
/23255.255.254.00.0.1.2555125102 × /24Larger office LAN (510 hosts)
/24255.255.255.00.0.0.2552562541 × /24Typical office LAN (old class C)
/25255.255.255.1280.0.0.1271281261/2 of a /24Smaller LAN or VLAN
/26255.255.255.1920.0.0.6364621/4 of a /24Smaller LAN or VLAN
/27255.255.255.2240.0.0.3132301/8 of a /24Small VLAN, phones, cameras
/28255.255.255.2400.0.0.1516141/16 of a /24Small VLAN, phones, cameras
/29255.255.255.2480.0.0.7861/32 of a /24Small fixed public block (5 usable)
/30255.255.255.2520.0.0.3421/64 of a /24Point-to-point (old style)
/31255.255.255.2540.0.0.1221/128 of a /24Point-to-point link (RFC 3021)
/32255.255.255.2550.0.0.0111/256 of a /24One host

IPv6 prefix reference

IPv6 prefix lengths
PrefixAddresses/64 LANs/48 sitesNibbleTypical use
/342,535,295,865,117,307,932,921,825,928,971,026,432 (2^125)2,305,843,009,213,693,95235,184,372,088,832NoAll global unicast (2000::/3)
/165,192,296,858,534,827,628,530,496,329,220,096 (2^112)281,474,976,710,6564,294,967,296Yes
/20324,518,553,658,426,726,783,156,020,576,256 (2^108)17,592,186,044,416268,435,456YesLarge provider allocation (RIPE minimum for some)
/29633,825,300,114,114,700,748,351,602,688 (2^99)34,359,738,368524,288NoRIPE allocation to a provider (often)
/3279,228,162,514,264,337,593,543,950,336 (2^96)4,294,967,29665,536YesProvider allocation (RIPE default)
/364,951,760,157,141,521,099,596,496,896 (2^92)268,435,4564,096Yes
/40309,485,009,821,345,068,724,781,056 (2^88)16,777,216256Yes
/4419,342,813,113,834,066,795,298,816 (2^84)1,048,57616Yes
/481,208,925,819,614,629,174,706,176 (2^80)65,5361YesOne site or organisation (RIPE PI / assignment)
/5275,557,863,725,914,323,419,136 (2^76)4,096Yes
/564,722,366,482,869,645,213,696 (2^72)256YesSmall site or home (common provider assignment)
/60295,147,905,179,352,825,856 (2^68)16YesSome home broadband (16 LANs)
/6418,446,744,073,709,551,616 (2^64)1YesOne LAN or VLAN (needed for SLAAC)
/7272,057,594,037,927,936 (2^56)1/256 of a /64Yes
/80281,474,976,710,656 (2^48)1/65,536 of a /64Yes
/964,294,967,2961/4,294,967,296 of a /64YesEmbeds an IPv4 address (NAT64)
/11265,5361/281,474,976,710,656 of a /64Yes
/1202561/72,057,594,037,927,936 of a /64Yes
/124161/1,152,921,504,606,846,976 of a /64Yes
/12641/4,611,686,018,427,387,904 of a /64No
/12721/9,223,372,036,854,775,808 of a /64NoPoint-to-point link (RFC 6164)
/12811/18,446,744,073,709,551,616 of a /64YesOne host or loopback

Private and special ranges

IPv4

Special-purpose ranges
RangeNameWhat it is
255.255.255.255/32Limited broadcastEvery host on the local network
0.0.0.0/8This networkNot routed; 0.0.0.0 means "any address" in settings
10.0.0.0/8Private (RFC 1918)Office and home networks; not routed on the internet
100.64.0.0/10Shared address space (CGNAT)Used by providers behind carrier-grade NAT (RFC 6598)
127.0.0.0/8LoopbackThis computer
169.254.0.0/16Link-local (APIPA)Self-assigned when no DHCP server answers
172.16.0.0/12Private (RFC 1918)Office and home networks; not routed on the internet
192.0.0.0/24IETF protocol assignmentsSpecial uses such as DS-Lite
192.0.2.0/24Documentation (TEST-NET-1)For examples; never used on a network
192.88.99.0/246to4 relay (deprecated)Formerly anycast for 6to4
192.168.0.0/16Private (RFC 1918)Office and home networks; not routed on the internet
198.18.0.0/15BenchmarkingNetwork equipment testing (RFC 2544)
198.51.100.0/24Documentation (TEST-NET-2)For examples; never used on a network
203.0.113.0/24Documentation (TEST-NET-3)For examples; never used on a network
224.0.0.0/4MulticastOne-to-many traffic, such as IPTV and routing protocols
240.0.0.0/4ReservedFuture use; not usable on most systems

IPv6

Special-purpose ranges
RangeNameWhat it is
::/128UnspecifiedNo address; :: means "any address" in settings
::1/128LoopbackThis computer
::ffff:0:0/96IPv4-mappedAn IPv4 address written as IPv6
64:ff9b::/96NAT64IPv4 addresses reached through a NAT64 gateway
100::/64Discard onlyTraffic sent here is dropped (RFC 6666)
2001:db8::/32DocumentationFor examples; never used on a network
2001::/32TeredoIPv6 tunnelled over IPv4 UDP
2002::/166to4IPv6 tunnelled over IPv4 (largely retired)
3fff::/20DocumentationFor examples (RFC 9637)
fc00::/7Unique local (ULA)Private IPv6, like RFC 1918; usually fd00::/8
fe80::/10Link-localEvery IPv6 interface has one; not routed
ff00::/8MulticastOne-to-many traffic; replaces broadcast
2000::/3Global unicastPublic internet addresses

About this tool

A network is written as an address and a prefix length, such as 192.168.1.0/24: the first 24 bits name the network and the rest number the devices on it. The calculator works out where the network starts and ends, how many devices it holds, its subnet and wildcard masks, and the reverse DNS zone to ask your provider for.

It also splits a network into equal smaller ones (one per VLAN or site), turns a range of addresses into the fewest CIDR blocks for a firewall rule, and lists every IPv4 prefix length and the common IPv6 ones in reference tables.

Common questions

Why are two addresses lost in every IPv4 subnet?

The first address names the network and the last is the broadcast address, so a /24 has 256 addresses but 254 for devices. A /31 (a link between two routers) and a /32 (one host) are the exceptions.

What size of IPv6 network should a LAN use?

Always /64. Devices pick their own address within it (SLAAC), which needs the full 64 bits. A site usually gets a /48 or /56 from its provider, which holds 65,536 or 256 LANs.

What is a wildcard mask?

The subnet mask turned inside out: 255.255.255.0 becomes 0.0.0.255. Cisco access lists and OSPF use it to say which bits must match.

Which ranges can I use inside an office?

IPv4: 10.0.0.0/8, 172.16.0.0/12 and 192.168.0.0/16. IPv6: unique local addresses from fd00::/8, though most networks use the public prefix from their provider.