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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.

Network224.246.0.0/16
Usable hosts65,534
Subnet mask255.255.0.0
Addresses65,536
Network address
224.246.0.0
Broadcast address
224.246.255.255
First usable
224.246.0.1
Last usable
224.246.255.254
Usable hosts
65,534 (65,536 less the network and broadcast addresses)
Subnet mask
255.255.0.0
Wildcard mask
0.0.255.255 (Cisco ACLs, OSPF)
Prefix length
/16
Type
Multicast 224.0.0.0/4
One-to-many traffic, such as IPTV and routing protocols
Old class
D (multicast)
As numbers
Hex E0F60000 · Integer 3774218240 to 3774283775
Reverse DNS zone
246.224.in-addr.arpa
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address11100000.11110110..00000000.00000000224.246.0.0
Subnet mask11111111.11111111..00000000.00000000255.255.0.0
Network11100000.11110110..00000000.00000000224.246.0.0
Broadcast11100000.11110110..11111111.11111111224.246.255.255
Split into smaller subnets/26
/17 (2)/18 (4)/19 (8)/20 (16)/21 (32)/22 (64)/23 (128)/24 (256)/25 (512)/26 (1,024)/27 (2,048)/28 (4,096)

224.246.0.0/16 makes 1,024 subnets of /26; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
1224.246.0.0/26224.246.0.1 to 224.246.0.62224.246.0.6362
2224.246.0.64/26224.246.0.65 to 224.246.0.126224.246.0.12762
3224.246.0.128/26224.246.0.129 to 224.246.0.190224.246.0.19162
4224.246.0.192/26224.246.0.193 to 224.246.0.254224.246.0.25562
5224.246.1.0/26224.246.1.1 to 224.246.1.62224.246.1.6362
6224.246.1.64/26224.246.1.65 to 224.246.1.126224.246.1.12762
7224.246.1.128/26224.246.1.129 to 224.246.1.190224.246.1.19162
8224.246.1.192/26224.246.1.193 to 224.246.1.254224.246.1.25562
9224.246.2.0/26224.246.2.1 to 224.246.2.62224.246.2.6362
10224.246.2.64/26224.246.2.65 to 224.246.2.126224.246.2.12762
11224.246.2.128/26224.246.2.129 to 224.246.2.190224.246.2.19162
12224.246.2.192/26224.246.2.193 to 224.246.2.254224.246.2.25562
13224.246.3.0/26224.246.3.1 to 224.246.3.62224.246.3.6362
14224.246.3.64/26224.246.3.65 to 224.246.3.126224.246.3.12762
15224.246.3.128/26224.246.3.129 to 224.246.3.190224.246.3.19162
16224.246.3.192/26224.246.3.193 to 224.246.3.254224.246.3.25562
17224.246.4.0/26224.246.4.1 to 224.246.4.62224.246.4.6362
18224.246.4.64/26224.246.4.65 to 224.246.4.126224.246.4.12762
19224.246.4.128/26224.246.4.129 to 224.246.4.190224.246.4.19162
20224.246.4.192/26224.246.4.193 to 224.246.4.254224.246.4.25562
21224.246.5.0/26224.246.5.1 to 224.246.5.62224.246.5.6362
22224.246.5.64/26224.246.5.65 to 224.246.5.126224.246.5.12762
23224.246.5.128/26224.246.5.129 to 224.246.5.190224.246.5.19162
24224.246.5.192/26224.246.5.193 to 224.246.5.254224.246.5.25562
25224.246.6.0/26224.246.6.1 to 224.246.6.62224.246.6.6362
26224.246.6.64/26224.246.6.65 to 224.246.6.126224.246.6.12762
27224.246.6.128/26224.246.6.129 to 224.246.6.190224.246.6.19162
28224.246.6.192/26224.246.6.193 to 224.246.6.254224.246.6.25562
29224.246.7.0/26224.246.7.1 to 224.246.7.62224.246.7.6362
30224.246.7.64/26224.246.7.65 to 224.246.7.126224.246.7.12762
31224.246.7.128/26224.246.7.129 to 224.246.7.190224.246.7.19162
32224.246.7.192/26224.246.7.193 to 224.246.7.254224.246.7.25562
33224.246.8.0/26224.246.8.1 to 224.246.8.62224.246.8.6362
34224.246.8.64/26224.246.8.65 to 224.246.8.126224.246.8.12762
35224.246.8.128/26224.246.8.129 to 224.246.8.190224.246.8.19162
36224.246.8.192/26224.246.8.193 to 224.246.8.254224.246.8.25562
37224.246.9.0/26224.246.9.1 to 224.246.9.62224.246.9.6362
38224.246.9.64/26224.246.9.65 to 224.246.9.126224.246.9.12762
39224.246.9.128/26224.246.9.129 to 224.246.9.190224.246.9.19162
40224.246.9.192/26224.246.9.193 to 224.246.9.254224.246.9.25562
41224.246.10.0/26224.246.10.1 to 224.246.10.62224.246.10.6362
42224.246.10.64/26224.246.10.65 to 224.246.10.126224.246.10.12762
43224.246.10.128/26224.246.10.129 to 224.246.10.190224.246.10.19162
44224.246.10.192/26224.246.10.193 to 224.246.10.254224.246.10.25562
45224.246.11.0/26224.246.11.1 to 224.246.11.62224.246.11.6362
46224.246.11.64/26224.246.11.65 to 224.246.11.126224.246.11.12762
47224.246.11.128/26224.246.11.129 to 224.246.11.190224.246.11.19162
48224.246.11.192/26224.246.11.193 to 224.246.11.254224.246.11.25562
49224.246.12.0/26224.246.12.1 to 224.246.12.62224.246.12.6362
50224.246.12.64/26224.246.12.65 to 224.246.12.126224.246.12.12762
51224.246.12.128/26224.246.12.129 to 224.246.12.190224.246.12.19162
52224.246.12.192/26224.246.12.193 to 224.246.12.254224.246.12.25562
53224.246.13.0/26224.246.13.1 to 224.246.13.62224.246.13.6362
54224.246.13.64/26224.246.13.65 to 224.246.13.126224.246.13.12762
55224.246.13.128/26224.246.13.129 to 224.246.13.190224.246.13.19162
56224.246.13.192/26224.246.13.193 to 224.246.13.254224.246.13.25562
57224.246.14.0/26224.246.14.1 to 224.246.14.62224.246.14.6362
58224.246.14.64/26224.246.14.65 to 224.246.14.126224.246.14.12762
59224.246.14.128/26224.246.14.129 to 224.246.14.190224.246.14.19162
60224.246.14.192/26224.246.14.193 to 224.246.14.254224.246.14.25562
61224.246.15.0/26224.246.15.1 to 224.246.15.62224.246.15.6362
62224.246.15.64/26224.246.15.65 to 224.246.15.126224.246.15.12762
63224.246.15.128/26224.246.15.129 to 224.246.15.190224.246.15.19162
64224.246.15.192/26224.246.15.193 to 224.246.15.254224.246.15.25562
65224.246.16.0/26224.246.16.1 to 224.246.16.62224.246.16.6362
66224.246.16.64/26224.246.16.65 to 224.246.16.126224.246.16.12762
67224.246.16.128/26224.246.16.129 to 224.246.16.190224.246.16.19162
68224.246.16.192/26224.246.16.193 to 224.246.16.254224.246.16.25562
69224.246.17.0/26224.246.17.1 to 224.246.17.62224.246.17.6362
70224.246.17.64/26224.246.17.65 to 224.246.17.126224.246.17.12762
71224.246.17.128/26224.246.17.129 to 224.246.17.190224.246.17.19162
72224.246.17.192/26224.246.17.193 to 224.246.17.254224.246.17.25562
73224.246.18.0/26224.246.18.1 to 224.246.18.62224.246.18.6362
74224.246.18.64/26224.246.18.65 to 224.246.18.126224.246.18.12762
75224.246.18.128/26224.246.18.129 to 224.246.18.190224.246.18.19162
76224.246.18.192/26224.246.18.193 to 224.246.18.254224.246.18.25562
77224.246.19.0/26224.246.19.1 to 224.246.19.62224.246.19.6362
78224.246.19.64/26224.246.19.65 to 224.246.19.126224.246.19.12762
79224.246.19.128/26224.246.19.129 to 224.246.19.190224.246.19.19162
80224.246.19.192/26224.246.19.193 to 224.246.19.254224.246.19.25562
81224.246.20.0/26224.246.20.1 to 224.246.20.62224.246.20.6362
82224.246.20.64/26224.246.20.65 to 224.246.20.126224.246.20.12762
83224.246.20.128/26224.246.20.129 to 224.246.20.190224.246.20.19162
84224.246.20.192/26224.246.20.193 to 224.246.20.254224.246.20.25562
85224.246.21.0/26224.246.21.1 to 224.246.21.62224.246.21.6362
86224.246.21.64/26224.246.21.65 to 224.246.21.126224.246.21.12762
87224.246.21.128/26224.246.21.129 to 224.246.21.190224.246.21.19162
88224.246.21.192/26224.246.21.193 to 224.246.21.254224.246.21.25562
89224.246.22.0/26224.246.22.1 to 224.246.22.62224.246.22.6362
90224.246.22.64/26224.246.22.65 to 224.246.22.126224.246.22.12762
91224.246.22.128/26224.246.22.129 to 224.246.22.190224.246.22.19162
92224.246.22.192/26224.246.22.193 to 224.246.22.254224.246.22.25562
93224.246.23.0/26224.246.23.1 to 224.246.23.62224.246.23.6362
94224.246.23.64/26224.246.23.65 to 224.246.23.126224.246.23.12762
95224.246.23.128/26224.246.23.129 to 224.246.23.190224.246.23.19162
96224.246.23.192/26224.246.23.193 to 224.246.23.254224.246.23.25562
97224.246.24.0/26224.246.24.1 to 224.246.24.62224.246.24.6362
98224.246.24.64/26224.246.24.65 to 224.246.24.126224.246.24.12762
99224.246.24.128/26224.246.24.129 to 224.246.24.190224.246.24.19162
100224.246.24.192/26224.246.24.193 to 224.246.24.254224.246.24.25562
101224.246.25.0/26224.246.25.1 to 224.246.25.62224.246.25.6362
102224.246.25.64/26224.246.25.65 to 224.246.25.126224.246.25.12762
103224.246.25.128/26224.246.25.129 to 224.246.25.190224.246.25.19162
104224.246.25.192/26224.246.25.193 to 224.246.25.254224.246.25.25562
105224.246.26.0/26224.246.26.1 to 224.246.26.62224.246.26.6362
106224.246.26.64/26224.246.26.65 to 224.246.26.126224.246.26.12762
107224.246.26.128/26224.246.26.129 to 224.246.26.190224.246.26.19162
108224.246.26.192/26224.246.26.193 to 224.246.26.254224.246.26.25562
109224.246.27.0/26224.246.27.1 to 224.246.27.62224.246.27.6362
110224.246.27.64/26224.246.27.65 to 224.246.27.126224.246.27.12762
111224.246.27.128/26224.246.27.129 to 224.246.27.190224.246.27.19162
112224.246.27.192/26224.246.27.193 to 224.246.27.254224.246.27.25562
113224.246.28.0/26224.246.28.1 to 224.246.28.62224.246.28.6362
114224.246.28.64/26224.246.28.65 to 224.246.28.126224.246.28.12762
115224.246.28.128/26224.246.28.129 to 224.246.28.190224.246.28.19162
116224.246.28.192/26224.246.28.193 to 224.246.28.254224.246.28.25562
117224.246.29.0/26224.246.29.1 to 224.246.29.62224.246.29.6362
118224.246.29.64/26224.246.29.65 to 224.246.29.126224.246.29.12762
119224.246.29.128/26224.246.29.129 to 224.246.29.190224.246.29.19162
120224.246.29.192/26224.246.29.193 to 224.246.29.254224.246.29.25562
121224.246.30.0/26224.246.30.1 to 224.246.30.62224.246.30.6362
122224.246.30.64/26224.246.30.65 to 224.246.30.126224.246.30.12762
123224.246.30.128/26224.246.30.129 to 224.246.30.190224.246.30.19162
124224.246.30.192/26224.246.30.193 to 224.246.30.254224.246.30.25562
125224.246.31.0/26224.246.31.1 to 224.246.31.62224.246.31.6362
126224.246.31.64/26224.246.31.65 to 224.246.31.126224.246.31.12762
127224.246.31.128/26224.246.31.129 to 224.246.31.190224.246.31.19162
128224.246.31.192/26224.246.31.193 to 224.246.31.254224.246.31.25562
129224.246.32.0/26224.246.32.1 to 224.246.32.62224.246.32.6362
130224.246.32.64/26224.246.32.65 to 224.246.32.126224.246.32.12762
131224.246.32.128/26224.246.32.129 to 224.246.32.190224.246.32.19162
132224.246.32.192/26224.246.32.193 to 224.246.32.254224.246.32.25562
133224.246.33.0/26224.246.33.1 to 224.246.33.62224.246.33.6362
134224.246.33.64/26224.246.33.65 to 224.246.33.126224.246.33.12762
135224.246.33.128/26224.246.33.129 to 224.246.33.190224.246.33.19162
136224.246.33.192/26224.246.33.193 to 224.246.33.254224.246.33.25562
137224.246.34.0/26224.246.34.1 to 224.246.34.62224.246.34.6362
138224.246.34.64/26224.246.34.65 to 224.246.34.126224.246.34.12762
139224.246.34.128/26224.246.34.129 to 224.246.34.190224.246.34.19162
140224.246.34.192/26224.246.34.193 to 224.246.34.254224.246.34.25562
141224.246.35.0/26224.246.35.1 to 224.246.35.62224.246.35.6362
142224.246.35.64/26224.246.35.65 to 224.246.35.126224.246.35.12762
143224.246.35.128/26224.246.35.129 to 224.246.35.190224.246.35.19162
144224.246.35.192/26224.246.35.193 to 224.246.35.254224.246.35.25562
145224.246.36.0/26224.246.36.1 to 224.246.36.62224.246.36.6362
146224.246.36.64/26224.246.36.65 to 224.246.36.126224.246.36.12762
147224.246.36.128/26224.246.36.129 to 224.246.36.190224.246.36.19162
148224.246.36.192/26224.246.36.193 to 224.246.36.254224.246.36.25562
149224.246.37.0/26224.246.37.1 to 224.246.37.62224.246.37.6362
150224.246.37.64/26224.246.37.65 to 224.246.37.126224.246.37.12762
151224.246.37.128/26224.246.37.129 to 224.246.37.190224.246.37.19162
152224.246.37.192/26224.246.37.193 to 224.246.37.254224.246.37.25562
153224.246.38.0/26224.246.38.1 to 224.246.38.62224.246.38.6362
154224.246.38.64/26224.246.38.65 to 224.246.38.126224.246.38.12762
155224.246.38.128/26224.246.38.129 to 224.246.38.190224.246.38.19162
156224.246.38.192/26224.246.38.193 to 224.246.38.254224.246.38.25562
157224.246.39.0/26224.246.39.1 to 224.246.39.62224.246.39.6362
158224.246.39.64/26224.246.39.65 to 224.246.39.126224.246.39.12762
159224.246.39.128/26224.246.39.129 to 224.246.39.190224.246.39.19162
160224.246.39.192/26224.246.39.193 to 224.246.39.254224.246.39.25562
161224.246.40.0/26224.246.40.1 to 224.246.40.62224.246.40.6362
162224.246.40.64/26224.246.40.65 to 224.246.40.126224.246.40.12762
163224.246.40.128/26224.246.40.129 to 224.246.40.190224.246.40.19162
164224.246.40.192/26224.246.40.193 to 224.246.40.254224.246.40.25562
165224.246.41.0/26224.246.41.1 to 224.246.41.62224.246.41.6362
166224.246.41.64/26224.246.41.65 to 224.246.41.126224.246.41.12762
167224.246.41.128/26224.246.41.129 to 224.246.41.190224.246.41.19162
168224.246.41.192/26224.246.41.193 to 224.246.41.254224.246.41.25562
169224.246.42.0/26224.246.42.1 to 224.246.42.62224.246.42.6362
170224.246.42.64/26224.246.42.65 to 224.246.42.126224.246.42.12762
171224.246.42.128/26224.246.42.129 to 224.246.42.190224.246.42.19162
172224.246.42.192/26224.246.42.193 to 224.246.42.254224.246.42.25562
173224.246.43.0/26224.246.43.1 to 224.246.43.62224.246.43.6362
174224.246.43.64/26224.246.43.65 to 224.246.43.126224.246.43.12762
175224.246.43.128/26224.246.43.129 to 224.246.43.190224.246.43.19162
176224.246.43.192/26224.246.43.193 to 224.246.43.254224.246.43.25562
177224.246.44.0/26224.246.44.1 to 224.246.44.62224.246.44.6362
178224.246.44.64/26224.246.44.65 to 224.246.44.126224.246.44.12762
179224.246.44.128/26224.246.44.129 to 224.246.44.190224.246.44.19162
180224.246.44.192/26224.246.44.193 to 224.246.44.254224.246.44.25562
181224.246.45.0/26224.246.45.1 to 224.246.45.62224.246.45.6362
182224.246.45.64/26224.246.45.65 to 224.246.45.126224.246.45.12762
183224.246.45.128/26224.246.45.129 to 224.246.45.190224.246.45.19162
184224.246.45.192/26224.246.45.193 to 224.246.45.254224.246.45.25562
185224.246.46.0/26224.246.46.1 to 224.246.46.62224.246.46.6362
186224.246.46.64/26224.246.46.65 to 224.246.46.126224.246.46.12762
187224.246.46.128/26224.246.46.129 to 224.246.46.190224.246.46.19162
188224.246.46.192/26224.246.46.193 to 224.246.46.254224.246.46.25562
189224.246.47.0/26224.246.47.1 to 224.246.47.62224.246.47.6362
190224.246.47.64/26224.246.47.65 to 224.246.47.126224.246.47.12762
191224.246.47.128/26224.246.47.129 to 224.246.47.190224.246.47.19162
192224.246.47.192/26224.246.47.193 to 224.246.47.254224.246.47.25562
193224.246.48.0/26224.246.48.1 to 224.246.48.62224.246.48.6362
194224.246.48.64/26224.246.48.65 to 224.246.48.126224.246.48.12762
195224.246.48.128/26224.246.48.129 to 224.246.48.190224.246.48.19162
196224.246.48.192/26224.246.48.193 to 224.246.48.254224.246.48.25562
197224.246.49.0/26224.246.49.1 to 224.246.49.62224.246.49.6362
198224.246.49.64/26224.246.49.65 to 224.246.49.126224.246.49.12762
199224.246.49.128/26224.246.49.129 to 224.246.49.190224.246.49.19162
200224.246.49.192/26224.246.49.193 to 224.246.49.254224.246.49.25562
201224.246.50.0/26224.246.50.1 to 224.246.50.62224.246.50.6362
202224.246.50.64/26224.246.50.65 to 224.246.50.126224.246.50.12762
203224.246.50.128/26224.246.50.129 to 224.246.50.190224.246.50.19162
204224.246.50.192/26224.246.50.193 to 224.246.50.254224.246.50.25562
205224.246.51.0/26224.246.51.1 to 224.246.51.62224.246.51.6362
206224.246.51.64/26224.246.51.65 to 224.246.51.126224.246.51.12762
207224.246.51.128/26224.246.51.129 to 224.246.51.190224.246.51.19162
208224.246.51.192/26224.246.51.193 to 224.246.51.254224.246.51.25562
209224.246.52.0/26224.246.52.1 to 224.246.52.62224.246.52.6362
210224.246.52.64/26224.246.52.65 to 224.246.52.126224.246.52.12762
211224.246.52.128/26224.246.52.129 to 224.246.52.190224.246.52.19162
212224.246.52.192/26224.246.52.193 to 224.246.52.254224.246.52.25562
213224.246.53.0/26224.246.53.1 to 224.246.53.62224.246.53.6362
214224.246.53.64/26224.246.53.65 to 224.246.53.126224.246.53.12762
215224.246.53.128/26224.246.53.129 to 224.246.53.190224.246.53.19162
216224.246.53.192/26224.246.53.193 to 224.246.53.254224.246.53.25562
217224.246.54.0/26224.246.54.1 to 224.246.54.62224.246.54.6362
218224.246.54.64/26224.246.54.65 to 224.246.54.126224.246.54.12762
219224.246.54.128/26224.246.54.129 to 224.246.54.190224.246.54.19162
220224.246.54.192/26224.246.54.193 to 224.246.54.254224.246.54.25562
221224.246.55.0/26224.246.55.1 to 224.246.55.62224.246.55.6362
222224.246.55.64/26224.246.55.65 to 224.246.55.126224.246.55.12762
223224.246.55.128/26224.246.55.129 to 224.246.55.190224.246.55.19162
224224.246.55.192/26224.246.55.193 to 224.246.55.254224.246.55.25562
225224.246.56.0/26224.246.56.1 to 224.246.56.62224.246.56.6362
226224.246.56.64/26224.246.56.65 to 224.246.56.126224.246.56.12762
227224.246.56.128/26224.246.56.129 to 224.246.56.190224.246.56.19162
228224.246.56.192/26224.246.56.193 to 224.246.56.254224.246.56.25562
229224.246.57.0/26224.246.57.1 to 224.246.57.62224.246.57.6362
230224.246.57.64/26224.246.57.65 to 224.246.57.126224.246.57.12762
231224.246.57.128/26224.246.57.129 to 224.246.57.190224.246.57.19162
232224.246.57.192/26224.246.57.193 to 224.246.57.254224.246.57.25562
233224.246.58.0/26224.246.58.1 to 224.246.58.62224.246.58.6362
234224.246.58.64/26224.246.58.65 to 224.246.58.126224.246.58.12762
235224.246.58.128/26224.246.58.129 to 224.246.58.190224.246.58.19162
236224.246.58.192/26224.246.58.193 to 224.246.58.254224.246.58.25562
237224.246.59.0/26224.246.59.1 to 224.246.59.62224.246.59.6362
238224.246.59.64/26224.246.59.65 to 224.246.59.126224.246.59.12762
239224.246.59.128/26224.246.59.129 to 224.246.59.190224.246.59.19162
240224.246.59.192/26224.246.59.193 to 224.246.59.254224.246.59.25562
241224.246.60.0/26224.246.60.1 to 224.246.60.62224.246.60.6362
242224.246.60.64/26224.246.60.65 to 224.246.60.126224.246.60.12762
243224.246.60.128/26224.246.60.129 to 224.246.60.190224.246.60.19162
244224.246.60.192/26224.246.60.193 to 224.246.60.254224.246.60.25562
245224.246.61.0/26224.246.61.1 to 224.246.61.62224.246.61.6362
246224.246.61.64/26224.246.61.65 to 224.246.61.126224.246.61.12762
247224.246.61.128/26224.246.61.129 to 224.246.61.190224.246.61.19162
248224.246.61.192/26224.246.61.193 to 224.246.61.254224.246.61.25562
249224.246.62.0/26224.246.62.1 to 224.246.62.62224.246.62.6362
250224.246.62.64/26224.246.62.65 to 224.246.62.126224.246.62.12762
251224.246.62.128/26224.246.62.129 to 224.246.62.190224.246.62.19162
252224.246.62.192/26224.246.62.193 to 224.246.62.254224.246.62.25562
253224.246.63.0/26224.246.63.1 to 224.246.63.62224.246.63.6362
254224.246.63.64/26224.246.63.65 to 224.246.63.126224.246.63.12762
255224.246.63.128/26224.246.63.129 to 224.246.63.190224.246.63.19162
256224.246.63.192/26224.246.63.193 to 224.246.63.254224.246.63.25562

IPv4 CIDR reference (/0 to /32)

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

IPv6 prefix reference

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

Private and special ranges

IPv4

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

IPv6

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

About this tool

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

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

Common questions

Why are two addresses lost in every IPv4 subnet?

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

What size of IPv6 network should a LAN use?

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

What is a wildcard mask?

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

Which ranges can I use inside an office?

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