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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.

Network224.168.0.0/14
Usable hosts262,142
Subnet mask255.252.0.0
Addresses262,144
Network address
224.168.0.0
Broadcast address
224.171.255.255
First usable
224.168.0.1
Last usable
224.171.255.254
Usable hosts
262,142 (262,144 less the network and broadcast addresses)
Subnet mask
255.252.0.0
Wildcard mask
0.3.255.255 (Cisco ACLs, OSPF)
Prefix length
/14
Type
Multicast 224.0.0.0/4
One-to-many traffic, such as IPTV and routing protocols
Old class
D (multicast)
As numbers
Hex E0A80000 · Integer 3769106432 to 3769368575
Reverse DNS zones
168.224.in-addr.arpa
169.224.in-addr.arpa
170.224.in-addr.arpa
171.224.in-addr.arpa
/14 is not on a 8-bit boundary, so it takes 4 /16 zones.
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address11100000.10101000.00000000.00000000224.168.0.0
Subnet mask11111111.11111100.00000000.00000000255.252.0.0
Network11100000.10101000.00000000.00000000224.168.0.0
Broadcast11100000.10101011.11111111.11111111224.171.255.255
Split into smaller subnets/25
/15 (2)/16 (4)/17 (8)/18 (16)/19 (32)/20 (64)/21 (128)/22 (256)/23 (512)/24 (1,024)/25 (2,048)/26 (4,096)

224.168.0.0/14 makes 2,048 subnets of /25; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
1224.168.0.0/25224.168.0.1 to 224.168.0.126224.168.0.127126
2224.168.0.128/25224.168.0.129 to 224.168.0.254224.168.0.255126
3224.168.1.0/25224.168.1.1 to 224.168.1.126224.168.1.127126
4224.168.1.128/25224.168.1.129 to 224.168.1.254224.168.1.255126
5224.168.2.0/25224.168.2.1 to 224.168.2.126224.168.2.127126
6224.168.2.128/25224.168.2.129 to 224.168.2.254224.168.2.255126
7224.168.3.0/25224.168.3.1 to 224.168.3.126224.168.3.127126
8224.168.3.128/25224.168.3.129 to 224.168.3.254224.168.3.255126
9224.168.4.0/25224.168.4.1 to 224.168.4.126224.168.4.127126
10224.168.4.128/25224.168.4.129 to 224.168.4.254224.168.4.255126
11224.168.5.0/25224.168.5.1 to 224.168.5.126224.168.5.127126
12224.168.5.128/25224.168.5.129 to 224.168.5.254224.168.5.255126
13224.168.6.0/25224.168.6.1 to 224.168.6.126224.168.6.127126
14224.168.6.128/25224.168.6.129 to 224.168.6.254224.168.6.255126
15224.168.7.0/25224.168.7.1 to 224.168.7.126224.168.7.127126
16224.168.7.128/25224.168.7.129 to 224.168.7.254224.168.7.255126
17224.168.8.0/25224.168.8.1 to 224.168.8.126224.168.8.127126
18224.168.8.128/25224.168.8.129 to 224.168.8.254224.168.8.255126
19224.168.9.0/25224.168.9.1 to 224.168.9.126224.168.9.127126
20224.168.9.128/25224.168.9.129 to 224.168.9.254224.168.9.255126
21224.168.10.0/25224.168.10.1 to 224.168.10.126224.168.10.127126
22224.168.10.128/25224.168.10.129 to 224.168.10.254224.168.10.255126
23224.168.11.0/25224.168.11.1 to 224.168.11.126224.168.11.127126
24224.168.11.128/25224.168.11.129 to 224.168.11.254224.168.11.255126
25224.168.12.0/25224.168.12.1 to 224.168.12.126224.168.12.127126
26224.168.12.128/25224.168.12.129 to 224.168.12.254224.168.12.255126
27224.168.13.0/25224.168.13.1 to 224.168.13.126224.168.13.127126
28224.168.13.128/25224.168.13.129 to 224.168.13.254224.168.13.255126
29224.168.14.0/25224.168.14.1 to 224.168.14.126224.168.14.127126
30224.168.14.128/25224.168.14.129 to 224.168.14.254224.168.14.255126
31224.168.15.0/25224.168.15.1 to 224.168.15.126224.168.15.127126
32224.168.15.128/25224.168.15.129 to 224.168.15.254224.168.15.255126
33224.168.16.0/25224.168.16.1 to 224.168.16.126224.168.16.127126
34224.168.16.128/25224.168.16.129 to 224.168.16.254224.168.16.255126
35224.168.17.0/25224.168.17.1 to 224.168.17.126224.168.17.127126
36224.168.17.128/25224.168.17.129 to 224.168.17.254224.168.17.255126
37224.168.18.0/25224.168.18.1 to 224.168.18.126224.168.18.127126
38224.168.18.128/25224.168.18.129 to 224.168.18.254224.168.18.255126
39224.168.19.0/25224.168.19.1 to 224.168.19.126224.168.19.127126
40224.168.19.128/25224.168.19.129 to 224.168.19.254224.168.19.255126
41224.168.20.0/25224.168.20.1 to 224.168.20.126224.168.20.127126
42224.168.20.128/25224.168.20.129 to 224.168.20.254224.168.20.255126
43224.168.21.0/25224.168.21.1 to 224.168.21.126224.168.21.127126
44224.168.21.128/25224.168.21.129 to 224.168.21.254224.168.21.255126
45224.168.22.0/25224.168.22.1 to 224.168.22.126224.168.22.127126
46224.168.22.128/25224.168.22.129 to 224.168.22.254224.168.22.255126
47224.168.23.0/25224.168.23.1 to 224.168.23.126224.168.23.127126
48224.168.23.128/25224.168.23.129 to 224.168.23.254224.168.23.255126
49224.168.24.0/25224.168.24.1 to 224.168.24.126224.168.24.127126
50224.168.24.128/25224.168.24.129 to 224.168.24.254224.168.24.255126
51224.168.25.0/25224.168.25.1 to 224.168.25.126224.168.25.127126
52224.168.25.128/25224.168.25.129 to 224.168.25.254224.168.25.255126
53224.168.26.0/25224.168.26.1 to 224.168.26.126224.168.26.127126
54224.168.26.128/25224.168.26.129 to 224.168.26.254224.168.26.255126
55224.168.27.0/25224.168.27.1 to 224.168.27.126224.168.27.127126
56224.168.27.128/25224.168.27.129 to 224.168.27.254224.168.27.255126
57224.168.28.0/25224.168.28.1 to 224.168.28.126224.168.28.127126
58224.168.28.128/25224.168.28.129 to 224.168.28.254224.168.28.255126
59224.168.29.0/25224.168.29.1 to 224.168.29.126224.168.29.127126
60224.168.29.128/25224.168.29.129 to 224.168.29.254224.168.29.255126
61224.168.30.0/25224.168.30.1 to 224.168.30.126224.168.30.127126
62224.168.30.128/25224.168.30.129 to 224.168.30.254224.168.30.255126
63224.168.31.0/25224.168.31.1 to 224.168.31.126224.168.31.127126
64224.168.31.128/25224.168.31.129 to 224.168.31.254224.168.31.255126
65224.168.32.0/25224.168.32.1 to 224.168.32.126224.168.32.127126
66224.168.32.128/25224.168.32.129 to 224.168.32.254224.168.32.255126
67224.168.33.0/25224.168.33.1 to 224.168.33.126224.168.33.127126
68224.168.33.128/25224.168.33.129 to 224.168.33.254224.168.33.255126
69224.168.34.0/25224.168.34.1 to 224.168.34.126224.168.34.127126
70224.168.34.128/25224.168.34.129 to 224.168.34.254224.168.34.255126
71224.168.35.0/25224.168.35.1 to 224.168.35.126224.168.35.127126
72224.168.35.128/25224.168.35.129 to 224.168.35.254224.168.35.255126
73224.168.36.0/25224.168.36.1 to 224.168.36.126224.168.36.127126
74224.168.36.128/25224.168.36.129 to 224.168.36.254224.168.36.255126
75224.168.37.0/25224.168.37.1 to 224.168.37.126224.168.37.127126
76224.168.37.128/25224.168.37.129 to 224.168.37.254224.168.37.255126
77224.168.38.0/25224.168.38.1 to 224.168.38.126224.168.38.127126
78224.168.38.128/25224.168.38.129 to 224.168.38.254224.168.38.255126
79224.168.39.0/25224.168.39.1 to 224.168.39.126224.168.39.127126
80224.168.39.128/25224.168.39.129 to 224.168.39.254224.168.39.255126
81224.168.40.0/25224.168.40.1 to 224.168.40.126224.168.40.127126
82224.168.40.128/25224.168.40.129 to 224.168.40.254224.168.40.255126
83224.168.41.0/25224.168.41.1 to 224.168.41.126224.168.41.127126
84224.168.41.128/25224.168.41.129 to 224.168.41.254224.168.41.255126
85224.168.42.0/25224.168.42.1 to 224.168.42.126224.168.42.127126
86224.168.42.128/25224.168.42.129 to 224.168.42.254224.168.42.255126
87224.168.43.0/25224.168.43.1 to 224.168.43.126224.168.43.127126
88224.168.43.128/25224.168.43.129 to 224.168.43.254224.168.43.255126
89224.168.44.0/25224.168.44.1 to 224.168.44.126224.168.44.127126
90224.168.44.128/25224.168.44.129 to 224.168.44.254224.168.44.255126
91224.168.45.0/25224.168.45.1 to 224.168.45.126224.168.45.127126
92224.168.45.128/25224.168.45.129 to 224.168.45.254224.168.45.255126
93224.168.46.0/25224.168.46.1 to 224.168.46.126224.168.46.127126
94224.168.46.128/25224.168.46.129 to 224.168.46.254224.168.46.255126
95224.168.47.0/25224.168.47.1 to 224.168.47.126224.168.47.127126
96224.168.47.128/25224.168.47.129 to 224.168.47.254224.168.47.255126
97224.168.48.0/25224.168.48.1 to 224.168.48.126224.168.48.127126
98224.168.48.128/25224.168.48.129 to 224.168.48.254224.168.48.255126
99224.168.49.0/25224.168.49.1 to 224.168.49.126224.168.49.127126
100224.168.49.128/25224.168.49.129 to 224.168.49.254224.168.49.255126
101224.168.50.0/25224.168.50.1 to 224.168.50.126224.168.50.127126
102224.168.50.128/25224.168.50.129 to 224.168.50.254224.168.50.255126
103224.168.51.0/25224.168.51.1 to 224.168.51.126224.168.51.127126
104224.168.51.128/25224.168.51.129 to 224.168.51.254224.168.51.255126
105224.168.52.0/25224.168.52.1 to 224.168.52.126224.168.52.127126
106224.168.52.128/25224.168.52.129 to 224.168.52.254224.168.52.255126
107224.168.53.0/25224.168.53.1 to 224.168.53.126224.168.53.127126
108224.168.53.128/25224.168.53.129 to 224.168.53.254224.168.53.255126
109224.168.54.0/25224.168.54.1 to 224.168.54.126224.168.54.127126
110224.168.54.128/25224.168.54.129 to 224.168.54.254224.168.54.255126
111224.168.55.0/25224.168.55.1 to 224.168.55.126224.168.55.127126
112224.168.55.128/25224.168.55.129 to 224.168.55.254224.168.55.255126
113224.168.56.0/25224.168.56.1 to 224.168.56.126224.168.56.127126
114224.168.56.128/25224.168.56.129 to 224.168.56.254224.168.56.255126
115224.168.57.0/25224.168.57.1 to 224.168.57.126224.168.57.127126
116224.168.57.128/25224.168.57.129 to 224.168.57.254224.168.57.255126
117224.168.58.0/25224.168.58.1 to 224.168.58.126224.168.58.127126
118224.168.58.128/25224.168.58.129 to 224.168.58.254224.168.58.255126
119224.168.59.0/25224.168.59.1 to 224.168.59.126224.168.59.127126
120224.168.59.128/25224.168.59.129 to 224.168.59.254224.168.59.255126
121224.168.60.0/25224.168.60.1 to 224.168.60.126224.168.60.127126
122224.168.60.128/25224.168.60.129 to 224.168.60.254224.168.60.255126
123224.168.61.0/25224.168.61.1 to 224.168.61.126224.168.61.127126
124224.168.61.128/25224.168.61.129 to 224.168.61.254224.168.61.255126
125224.168.62.0/25224.168.62.1 to 224.168.62.126224.168.62.127126
126224.168.62.128/25224.168.62.129 to 224.168.62.254224.168.62.255126
127224.168.63.0/25224.168.63.1 to 224.168.63.126224.168.63.127126
128224.168.63.128/25224.168.63.129 to 224.168.63.254224.168.63.255126
129224.168.64.0/25224.168.64.1 to 224.168.64.126224.168.64.127126
130224.168.64.128/25224.168.64.129 to 224.168.64.254224.168.64.255126
131224.168.65.0/25224.168.65.1 to 224.168.65.126224.168.65.127126
132224.168.65.128/25224.168.65.129 to 224.168.65.254224.168.65.255126
133224.168.66.0/25224.168.66.1 to 224.168.66.126224.168.66.127126
134224.168.66.128/25224.168.66.129 to 224.168.66.254224.168.66.255126
135224.168.67.0/25224.168.67.1 to 224.168.67.126224.168.67.127126
136224.168.67.128/25224.168.67.129 to 224.168.67.254224.168.67.255126
137224.168.68.0/25224.168.68.1 to 224.168.68.126224.168.68.127126
138224.168.68.128/25224.168.68.129 to 224.168.68.254224.168.68.255126
139224.168.69.0/25224.168.69.1 to 224.168.69.126224.168.69.127126
140224.168.69.128/25224.168.69.129 to 224.168.69.254224.168.69.255126
141224.168.70.0/25224.168.70.1 to 224.168.70.126224.168.70.127126
142224.168.70.128/25224.168.70.129 to 224.168.70.254224.168.70.255126
143224.168.71.0/25224.168.71.1 to 224.168.71.126224.168.71.127126
144224.168.71.128/25224.168.71.129 to 224.168.71.254224.168.71.255126
145224.168.72.0/25224.168.72.1 to 224.168.72.126224.168.72.127126
146224.168.72.128/25224.168.72.129 to 224.168.72.254224.168.72.255126
147224.168.73.0/25224.168.73.1 to 224.168.73.126224.168.73.127126
148224.168.73.128/25224.168.73.129 to 224.168.73.254224.168.73.255126
149224.168.74.0/25224.168.74.1 to 224.168.74.126224.168.74.127126
150224.168.74.128/25224.168.74.129 to 224.168.74.254224.168.74.255126
151224.168.75.0/25224.168.75.1 to 224.168.75.126224.168.75.127126
152224.168.75.128/25224.168.75.129 to 224.168.75.254224.168.75.255126
153224.168.76.0/25224.168.76.1 to 224.168.76.126224.168.76.127126
154224.168.76.128/25224.168.76.129 to 224.168.76.254224.168.76.255126
155224.168.77.0/25224.168.77.1 to 224.168.77.126224.168.77.127126
156224.168.77.128/25224.168.77.129 to 224.168.77.254224.168.77.255126
157224.168.78.0/25224.168.78.1 to 224.168.78.126224.168.78.127126
158224.168.78.128/25224.168.78.129 to 224.168.78.254224.168.78.255126
159224.168.79.0/25224.168.79.1 to 224.168.79.126224.168.79.127126
160224.168.79.128/25224.168.79.129 to 224.168.79.254224.168.79.255126
161224.168.80.0/25224.168.80.1 to 224.168.80.126224.168.80.127126
162224.168.80.128/25224.168.80.129 to 224.168.80.254224.168.80.255126
163224.168.81.0/25224.168.81.1 to 224.168.81.126224.168.81.127126
164224.168.81.128/25224.168.81.129 to 224.168.81.254224.168.81.255126
165224.168.82.0/25224.168.82.1 to 224.168.82.126224.168.82.127126
166224.168.82.128/25224.168.82.129 to 224.168.82.254224.168.82.255126
167224.168.83.0/25224.168.83.1 to 224.168.83.126224.168.83.127126
168224.168.83.128/25224.168.83.129 to 224.168.83.254224.168.83.255126
169224.168.84.0/25224.168.84.1 to 224.168.84.126224.168.84.127126
170224.168.84.128/25224.168.84.129 to 224.168.84.254224.168.84.255126
171224.168.85.0/25224.168.85.1 to 224.168.85.126224.168.85.127126
172224.168.85.128/25224.168.85.129 to 224.168.85.254224.168.85.255126
173224.168.86.0/25224.168.86.1 to 224.168.86.126224.168.86.127126
174224.168.86.128/25224.168.86.129 to 224.168.86.254224.168.86.255126
175224.168.87.0/25224.168.87.1 to 224.168.87.126224.168.87.127126
176224.168.87.128/25224.168.87.129 to 224.168.87.254224.168.87.255126
177224.168.88.0/25224.168.88.1 to 224.168.88.126224.168.88.127126
178224.168.88.128/25224.168.88.129 to 224.168.88.254224.168.88.255126
179224.168.89.0/25224.168.89.1 to 224.168.89.126224.168.89.127126
180224.168.89.128/25224.168.89.129 to 224.168.89.254224.168.89.255126
181224.168.90.0/25224.168.90.1 to 224.168.90.126224.168.90.127126
182224.168.90.128/25224.168.90.129 to 224.168.90.254224.168.90.255126
183224.168.91.0/25224.168.91.1 to 224.168.91.126224.168.91.127126
184224.168.91.128/25224.168.91.129 to 224.168.91.254224.168.91.255126
185224.168.92.0/25224.168.92.1 to 224.168.92.126224.168.92.127126
186224.168.92.128/25224.168.92.129 to 224.168.92.254224.168.92.255126
187224.168.93.0/25224.168.93.1 to 224.168.93.126224.168.93.127126
188224.168.93.128/25224.168.93.129 to 224.168.93.254224.168.93.255126
189224.168.94.0/25224.168.94.1 to 224.168.94.126224.168.94.127126
190224.168.94.128/25224.168.94.129 to 224.168.94.254224.168.94.255126
191224.168.95.0/25224.168.95.1 to 224.168.95.126224.168.95.127126
192224.168.95.128/25224.168.95.129 to 224.168.95.254224.168.95.255126
193224.168.96.0/25224.168.96.1 to 224.168.96.126224.168.96.127126
194224.168.96.128/25224.168.96.129 to 224.168.96.254224.168.96.255126
195224.168.97.0/25224.168.97.1 to 224.168.97.126224.168.97.127126
196224.168.97.128/25224.168.97.129 to 224.168.97.254224.168.97.255126
197224.168.98.0/25224.168.98.1 to 224.168.98.126224.168.98.127126
198224.168.98.128/25224.168.98.129 to 224.168.98.254224.168.98.255126
199224.168.99.0/25224.168.99.1 to 224.168.99.126224.168.99.127126
200224.168.99.128/25224.168.99.129 to 224.168.99.254224.168.99.255126
201224.168.100.0/25224.168.100.1 to 224.168.100.126224.168.100.127126
202224.168.100.128/25224.168.100.129 to 224.168.100.254224.168.100.255126
203224.168.101.0/25224.168.101.1 to 224.168.101.126224.168.101.127126
204224.168.101.128/25224.168.101.129 to 224.168.101.254224.168.101.255126
205224.168.102.0/25224.168.102.1 to 224.168.102.126224.168.102.127126
206224.168.102.128/25224.168.102.129 to 224.168.102.254224.168.102.255126
207224.168.103.0/25224.168.103.1 to 224.168.103.126224.168.103.127126
208224.168.103.128/25224.168.103.129 to 224.168.103.254224.168.103.255126
209224.168.104.0/25224.168.104.1 to 224.168.104.126224.168.104.127126
210224.168.104.128/25224.168.104.129 to 224.168.104.254224.168.104.255126
211224.168.105.0/25224.168.105.1 to 224.168.105.126224.168.105.127126
212224.168.105.128/25224.168.105.129 to 224.168.105.254224.168.105.255126
213224.168.106.0/25224.168.106.1 to 224.168.106.126224.168.106.127126
214224.168.106.128/25224.168.106.129 to 224.168.106.254224.168.106.255126
215224.168.107.0/25224.168.107.1 to 224.168.107.126224.168.107.127126
216224.168.107.128/25224.168.107.129 to 224.168.107.254224.168.107.255126
217224.168.108.0/25224.168.108.1 to 224.168.108.126224.168.108.127126
218224.168.108.128/25224.168.108.129 to 224.168.108.254224.168.108.255126
219224.168.109.0/25224.168.109.1 to 224.168.109.126224.168.109.127126
220224.168.109.128/25224.168.109.129 to 224.168.109.254224.168.109.255126
221224.168.110.0/25224.168.110.1 to 224.168.110.126224.168.110.127126
222224.168.110.128/25224.168.110.129 to 224.168.110.254224.168.110.255126
223224.168.111.0/25224.168.111.1 to 224.168.111.126224.168.111.127126
224224.168.111.128/25224.168.111.129 to 224.168.111.254224.168.111.255126
225224.168.112.0/25224.168.112.1 to 224.168.112.126224.168.112.127126
226224.168.112.128/25224.168.112.129 to 224.168.112.254224.168.112.255126
227224.168.113.0/25224.168.113.1 to 224.168.113.126224.168.113.127126
228224.168.113.128/25224.168.113.129 to 224.168.113.254224.168.113.255126
229224.168.114.0/25224.168.114.1 to 224.168.114.126224.168.114.127126
230224.168.114.128/25224.168.114.129 to 224.168.114.254224.168.114.255126
231224.168.115.0/25224.168.115.1 to 224.168.115.126224.168.115.127126
232224.168.115.128/25224.168.115.129 to 224.168.115.254224.168.115.255126
233224.168.116.0/25224.168.116.1 to 224.168.116.126224.168.116.127126
234224.168.116.128/25224.168.116.129 to 224.168.116.254224.168.116.255126
235224.168.117.0/25224.168.117.1 to 224.168.117.126224.168.117.127126
236224.168.117.128/25224.168.117.129 to 224.168.117.254224.168.117.255126
237224.168.118.0/25224.168.118.1 to 224.168.118.126224.168.118.127126
238224.168.118.128/25224.168.118.129 to 224.168.118.254224.168.118.255126
239224.168.119.0/25224.168.119.1 to 224.168.119.126224.168.119.127126
240224.168.119.128/25224.168.119.129 to 224.168.119.254224.168.119.255126
241224.168.120.0/25224.168.120.1 to 224.168.120.126224.168.120.127126
242224.168.120.128/25224.168.120.129 to 224.168.120.254224.168.120.255126
243224.168.121.0/25224.168.121.1 to 224.168.121.126224.168.121.127126
244224.168.121.128/25224.168.121.129 to 224.168.121.254224.168.121.255126
245224.168.122.0/25224.168.122.1 to 224.168.122.126224.168.122.127126
246224.168.122.128/25224.168.122.129 to 224.168.122.254224.168.122.255126
247224.168.123.0/25224.168.123.1 to 224.168.123.126224.168.123.127126
248224.168.123.128/25224.168.123.129 to 224.168.123.254224.168.123.255126
249224.168.124.0/25224.168.124.1 to 224.168.124.126224.168.124.127126
250224.168.124.128/25224.168.124.129 to 224.168.124.254224.168.124.255126
251224.168.125.0/25224.168.125.1 to 224.168.125.126224.168.125.127126
252224.168.125.128/25224.168.125.129 to 224.168.125.254224.168.125.255126
253224.168.126.0/25224.168.126.1 to 224.168.126.126224.168.126.127126
254224.168.126.128/25224.168.126.129 to 224.168.126.254224.168.126.255126
255224.168.127.0/25224.168.127.1 to 224.168.127.126224.168.127.127126
256224.168.127.128/25224.168.127.129 to 224.168.127.254224.168.127.255126

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.