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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.

Network186.96.0.0/16
Usable hosts65,534
Subnet mask255.255.0.0
Addresses65,536
Network address
186.96.0.0
Broadcast address
186.96.255.255
First usable
186.96.0.1
Last usable
186.96.255.254
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
Public public
Old class
B (default /16)
As numbers
Hex BA600000 · Integer 3126853632 to 3126919167
Reverse DNS zone
96.186.in-addr.arpa
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address10111010.01100000..00000000.00000000186.96.0.0
Subnet mask11111111.11111111..00000000.00000000255.255.0.0
Network10111010.01100000..00000000.00000000186.96.0.0
Broadcast10111010.01100000..11111111.11111111186.96.255.255
Split into smaller subnets/25
/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)

186.96.0.0/16 makes 512 subnets of /25; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
1186.96.0.0/25186.96.0.1 to 186.96.0.126186.96.0.127126
2186.96.0.128/25186.96.0.129 to 186.96.0.254186.96.0.255126
3186.96.1.0/25186.96.1.1 to 186.96.1.126186.96.1.127126
4186.96.1.128/25186.96.1.129 to 186.96.1.254186.96.1.255126
5186.96.2.0/25186.96.2.1 to 186.96.2.126186.96.2.127126
6186.96.2.128/25186.96.2.129 to 186.96.2.254186.96.2.255126
7186.96.3.0/25186.96.3.1 to 186.96.3.126186.96.3.127126
8186.96.3.128/25186.96.3.129 to 186.96.3.254186.96.3.255126
9186.96.4.0/25186.96.4.1 to 186.96.4.126186.96.4.127126
10186.96.4.128/25186.96.4.129 to 186.96.4.254186.96.4.255126
11186.96.5.0/25186.96.5.1 to 186.96.5.126186.96.5.127126
12186.96.5.128/25186.96.5.129 to 186.96.5.254186.96.5.255126
13186.96.6.0/25186.96.6.1 to 186.96.6.126186.96.6.127126
14186.96.6.128/25186.96.6.129 to 186.96.6.254186.96.6.255126
15186.96.7.0/25186.96.7.1 to 186.96.7.126186.96.7.127126
16186.96.7.128/25186.96.7.129 to 186.96.7.254186.96.7.255126
17186.96.8.0/25186.96.8.1 to 186.96.8.126186.96.8.127126
18186.96.8.128/25186.96.8.129 to 186.96.8.254186.96.8.255126
19186.96.9.0/25186.96.9.1 to 186.96.9.126186.96.9.127126
20186.96.9.128/25186.96.9.129 to 186.96.9.254186.96.9.255126
21186.96.10.0/25186.96.10.1 to 186.96.10.126186.96.10.127126
22186.96.10.128/25186.96.10.129 to 186.96.10.254186.96.10.255126
23186.96.11.0/25186.96.11.1 to 186.96.11.126186.96.11.127126
24186.96.11.128/25186.96.11.129 to 186.96.11.254186.96.11.255126
25186.96.12.0/25186.96.12.1 to 186.96.12.126186.96.12.127126
26186.96.12.128/25186.96.12.129 to 186.96.12.254186.96.12.255126
27186.96.13.0/25186.96.13.1 to 186.96.13.126186.96.13.127126
28186.96.13.128/25186.96.13.129 to 186.96.13.254186.96.13.255126
29186.96.14.0/25186.96.14.1 to 186.96.14.126186.96.14.127126
30186.96.14.128/25186.96.14.129 to 186.96.14.254186.96.14.255126
31186.96.15.0/25186.96.15.1 to 186.96.15.126186.96.15.127126
32186.96.15.128/25186.96.15.129 to 186.96.15.254186.96.15.255126
33186.96.16.0/25186.96.16.1 to 186.96.16.126186.96.16.127126
34186.96.16.128/25186.96.16.129 to 186.96.16.254186.96.16.255126
35186.96.17.0/25186.96.17.1 to 186.96.17.126186.96.17.127126
36186.96.17.128/25186.96.17.129 to 186.96.17.254186.96.17.255126
37186.96.18.0/25186.96.18.1 to 186.96.18.126186.96.18.127126
38186.96.18.128/25186.96.18.129 to 186.96.18.254186.96.18.255126
39186.96.19.0/25186.96.19.1 to 186.96.19.126186.96.19.127126
40186.96.19.128/25186.96.19.129 to 186.96.19.254186.96.19.255126
41186.96.20.0/25186.96.20.1 to 186.96.20.126186.96.20.127126
42186.96.20.128/25186.96.20.129 to 186.96.20.254186.96.20.255126
43186.96.21.0/25186.96.21.1 to 186.96.21.126186.96.21.127126
44186.96.21.128/25186.96.21.129 to 186.96.21.254186.96.21.255126
45186.96.22.0/25186.96.22.1 to 186.96.22.126186.96.22.127126
46186.96.22.128/25186.96.22.129 to 186.96.22.254186.96.22.255126
47186.96.23.0/25186.96.23.1 to 186.96.23.126186.96.23.127126
48186.96.23.128/25186.96.23.129 to 186.96.23.254186.96.23.255126
49186.96.24.0/25186.96.24.1 to 186.96.24.126186.96.24.127126
50186.96.24.128/25186.96.24.129 to 186.96.24.254186.96.24.255126
51186.96.25.0/25186.96.25.1 to 186.96.25.126186.96.25.127126
52186.96.25.128/25186.96.25.129 to 186.96.25.254186.96.25.255126
53186.96.26.0/25186.96.26.1 to 186.96.26.126186.96.26.127126
54186.96.26.128/25186.96.26.129 to 186.96.26.254186.96.26.255126
55186.96.27.0/25186.96.27.1 to 186.96.27.126186.96.27.127126
56186.96.27.128/25186.96.27.129 to 186.96.27.254186.96.27.255126
57186.96.28.0/25186.96.28.1 to 186.96.28.126186.96.28.127126
58186.96.28.128/25186.96.28.129 to 186.96.28.254186.96.28.255126
59186.96.29.0/25186.96.29.1 to 186.96.29.126186.96.29.127126
60186.96.29.128/25186.96.29.129 to 186.96.29.254186.96.29.255126
61186.96.30.0/25186.96.30.1 to 186.96.30.126186.96.30.127126
62186.96.30.128/25186.96.30.129 to 186.96.30.254186.96.30.255126
63186.96.31.0/25186.96.31.1 to 186.96.31.126186.96.31.127126
64186.96.31.128/25186.96.31.129 to 186.96.31.254186.96.31.255126
65186.96.32.0/25186.96.32.1 to 186.96.32.126186.96.32.127126
66186.96.32.128/25186.96.32.129 to 186.96.32.254186.96.32.255126
67186.96.33.0/25186.96.33.1 to 186.96.33.126186.96.33.127126
68186.96.33.128/25186.96.33.129 to 186.96.33.254186.96.33.255126
69186.96.34.0/25186.96.34.1 to 186.96.34.126186.96.34.127126
70186.96.34.128/25186.96.34.129 to 186.96.34.254186.96.34.255126
71186.96.35.0/25186.96.35.1 to 186.96.35.126186.96.35.127126
72186.96.35.128/25186.96.35.129 to 186.96.35.254186.96.35.255126
73186.96.36.0/25186.96.36.1 to 186.96.36.126186.96.36.127126
74186.96.36.128/25186.96.36.129 to 186.96.36.254186.96.36.255126
75186.96.37.0/25186.96.37.1 to 186.96.37.126186.96.37.127126
76186.96.37.128/25186.96.37.129 to 186.96.37.254186.96.37.255126
77186.96.38.0/25186.96.38.1 to 186.96.38.126186.96.38.127126
78186.96.38.128/25186.96.38.129 to 186.96.38.254186.96.38.255126
79186.96.39.0/25186.96.39.1 to 186.96.39.126186.96.39.127126
80186.96.39.128/25186.96.39.129 to 186.96.39.254186.96.39.255126
81186.96.40.0/25186.96.40.1 to 186.96.40.126186.96.40.127126
82186.96.40.128/25186.96.40.129 to 186.96.40.254186.96.40.255126
83186.96.41.0/25186.96.41.1 to 186.96.41.126186.96.41.127126
84186.96.41.128/25186.96.41.129 to 186.96.41.254186.96.41.255126
85186.96.42.0/25186.96.42.1 to 186.96.42.126186.96.42.127126
86186.96.42.128/25186.96.42.129 to 186.96.42.254186.96.42.255126
87186.96.43.0/25186.96.43.1 to 186.96.43.126186.96.43.127126
88186.96.43.128/25186.96.43.129 to 186.96.43.254186.96.43.255126
89186.96.44.0/25186.96.44.1 to 186.96.44.126186.96.44.127126
90186.96.44.128/25186.96.44.129 to 186.96.44.254186.96.44.255126
91186.96.45.0/25186.96.45.1 to 186.96.45.126186.96.45.127126
92186.96.45.128/25186.96.45.129 to 186.96.45.254186.96.45.255126
93186.96.46.0/25186.96.46.1 to 186.96.46.126186.96.46.127126
94186.96.46.128/25186.96.46.129 to 186.96.46.254186.96.46.255126
95186.96.47.0/25186.96.47.1 to 186.96.47.126186.96.47.127126
96186.96.47.128/25186.96.47.129 to 186.96.47.254186.96.47.255126
97186.96.48.0/25186.96.48.1 to 186.96.48.126186.96.48.127126
98186.96.48.128/25186.96.48.129 to 186.96.48.254186.96.48.255126
99186.96.49.0/25186.96.49.1 to 186.96.49.126186.96.49.127126
100186.96.49.128/25186.96.49.129 to 186.96.49.254186.96.49.255126
101186.96.50.0/25186.96.50.1 to 186.96.50.126186.96.50.127126
102186.96.50.128/25186.96.50.129 to 186.96.50.254186.96.50.255126
103186.96.51.0/25186.96.51.1 to 186.96.51.126186.96.51.127126
104186.96.51.128/25186.96.51.129 to 186.96.51.254186.96.51.255126
105186.96.52.0/25186.96.52.1 to 186.96.52.126186.96.52.127126
106186.96.52.128/25186.96.52.129 to 186.96.52.254186.96.52.255126
107186.96.53.0/25186.96.53.1 to 186.96.53.126186.96.53.127126
108186.96.53.128/25186.96.53.129 to 186.96.53.254186.96.53.255126
109186.96.54.0/25186.96.54.1 to 186.96.54.126186.96.54.127126
110186.96.54.128/25186.96.54.129 to 186.96.54.254186.96.54.255126
111186.96.55.0/25186.96.55.1 to 186.96.55.126186.96.55.127126
112186.96.55.128/25186.96.55.129 to 186.96.55.254186.96.55.255126
113186.96.56.0/25186.96.56.1 to 186.96.56.126186.96.56.127126
114186.96.56.128/25186.96.56.129 to 186.96.56.254186.96.56.255126
115186.96.57.0/25186.96.57.1 to 186.96.57.126186.96.57.127126
116186.96.57.128/25186.96.57.129 to 186.96.57.254186.96.57.255126
117186.96.58.0/25186.96.58.1 to 186.96.58.126186.96.58.127126
118186.96.58.128/25186.96.58.129 to 186.96.58.254186.96.58.255126
119186.96.59.0/25186.96.59.1 to 186.96.59.126186.96.59.127126
120186.96.59.128/25186.96.59.129 to 186.96.59.254186.96.59.255126
121186.96.60.0/25186.96.60.1 to 186.96.60.126186.96.60.127126
122186.96.60.128/25186.96.60.129 to 186.96.60.254186.96.60.255126
123186.96.61.0/25186.96.61.1 to 186.96.61.126186.96.61.127126
124186.96.61.128/25186.96.61.129 to 186.96.61.254186.96.61.255126
125186.96.62.0/25186.96.62.1 to 186.96.62.126186.96.62.127126
126186.96.62.128/25186.96.62.129 to 186.96.62.254186.96.62.255126
127186.96.63.0/25186.96.63.1 to 186.96.63.126186.96.63.127126
128186.96.63.128/25186.96.63.129 to 186.96.63.254186.96.63.255126
129186.96.64.0/25186.96.64.1 to 186.96.64.126186.96.64.127126
130186.96.64.128/25186.96.64.129 to 186.96.64.254186.96.64.255126
131186.96.65.0/25186.96.65.1 to 186.96.65.126186.96.65.127126
132186.96.65.128/25186.96.65.129 to 186.96.65.254186.96.65.255126
133186.96.66.0/25186.96.66.1 to 186.96.66.126186.96.66.127126
134186.96.66.128/25186.96.66.129 to 186.96.66.254186.96.66.255126
135186.96.67.0/25186.96.67.1 to 186.96.67.126186.96.67.127126
136186.96.67.128/25186.96.67.129 to 186.96.67.254186.96.67.255126
137186.96.68.0/25186.96.68.1 to 186.96.68.126186.96.68.127126
138186.96.68.128/25186.96.68.129 to 186.96.68.254186.96.68.255126
139186.96.69.0/25186.96.69.1 to 186.96.69.126186.96.69.127126
140186.96.69.128/25186.96.69.129 to 186.96.69.254186.96.69.255126
141186.96.70.0/25186.96.70.1 to 186.96.70.126186.96.70.127126
142186.96.70.128/25186.96.70.129 to 186.96.70.254186.96.70.255126
143186.96.71.0/25186.96.71.1 to 186.96.71.126186.96.71.127126
144186.96.71.128/25186.96.71.129 to 186.96.71.254186.96.71.255126
145186.96.72.0/25186.96.72.1 to 186.96.72.126186.96.72.127126
146186.96.72.128/25186.96.72.129 to 186.96.72.254186.96.72.255126
147186.96.73.0/25186.96.73.1 to 186.96.73.126186.96.73.127126
148186.96.73.128/25186.96.73.129 to 186.96.73.254186.96.73.255126
149186.96.74.0/25186.96.74.1 to 186.96.74.126186.96.74.127126
150186.96.74.128/25186.96.74.129 to 186.96.74.254186.96.74.255126
151186.96.75.0/25186.96.75.1 to 186.96.75.126186.96.75.127126
152186.96.75.128/25186.96.75.129 to 186.96.75.254186.96.75.255126
153186.96.76.0/25186.96.76.1 to 186.96.76.126186.96.76.127126
154186.96.76.128/25186.96.76.129 to 186.96.76.254186.96.76.255126
155186.96.77.0/25186.96.77.1 to 186.96.77.126186.96.77.127126
156186.96.77.128/25186.96.77.129 to 186.96.77.254186.96.77.255126
157186.96.78.0/25186.96.78.1 to 186.96.78.126186.96.78.127126
158186.96.78.128/25186.96.78.129 to 186.96.78.254186.96.78.255126
159186.96.79.0/25186.96.79.1 to 186.96.79.126186.96.79.127126
160186.96.79.128/25186.96.79.129 to 186.96.79.254186.96.79.255126
161186.96.80.0/25186.96.80.1 to 186.96.80.126186.96.80.127126
162186.96.80.128/25186.96.80.129 to 186.96.80.254186.96.80.255126
163186.96.81.0/25186.96.81.1 to 186.96.81.126186.96.81.127126
164186.96.81.128/25186.96.81.129 to 186.96.81.254186.96.81.255126
165186.96.82.0/25186.96.82.1 to 186.96.82.126186.96.82.127126
166186.96.82.128/25186.96.82.129 to 186.96.82.254186.96.82.255126
167186.96.83.0/25186.96.83.1 to 186.96.83.126186.96.83.127126
168186.96.83.128/25186.96.83.129 to 186.96.83.254186.96.83.255126
169186.96.84.0/25186.96.84.1 to 186.96.84.126186.96.84.127126
170186.96.84.128/25186.96.84.129 to 186.96.84.254186.96.84.255126
171186.96.85.0/25186.96.85.1 to 186.96.85.126186.96.85.127126
172186.96.85.128/25186.96.85.129 to 186.96.85.254186.96.85.255126
173186.96.86.0/25186.96.86.1 to 186.96.86.126186.96.86.127126
174186.96.86.128/25186.96.86.129 to 186.96.86.254186.96.86.255126
175186.96.87.0/25186.96.87.1 to 186.96.87.126186.96.87.127126
176186.96.87.128/25186.96.87.129 to 186.96.87.254186.96.87.255126
177186.96.88.0/25186.96.88.1 to 186.96.88.126186.96.88.127126
178186.96.88.128/25186.96.88.129 to 186.96.88.254186.96.88.255126
179186.96.89.0/25186.96.89.1 to 186.96.89.126186.96.89.127126
180186.96.89.128/25186.96.89.129 to 186.96.89.254186.96.89.255126
181186.96.90.0/25186.96.90.1 to 186.96.90.126186.96.90.127126
182186.96.90.128/25186.96.90.129 to 186.96.90.254186.96.90.255126
183186.96.91.0/25186.96.91.1 to 186.96.91.126186.96.91.127126
184186.96.91.128/25186.96.91.129 to 186.96.91.254186.96.91.255126
185186.96.92.0/25186.96.92.1 to 186.96.92.126186.96.92.127126
186186.96.92.128/25186.96.92.129 to 186.96.92.254186.96.92.255126
187186.96.93.0/25186.96.93.1 to 186.96.93.126186.96.93.127126
188186.96.93.128/25186.96.93.129 to 186.96.93.254186.96.93.255126
189186.96.94.0/25186.96.94.1 to 186.96.94.126186.96.94.127126
190186.96.94.128/25186.96.94.129 to 186.96.94.254186.96.94.255126
191186.96.95.0/25186.96.95.1 to 186.96.95.126186.96.95.127126
192186.96.95.128/25186.96.95.129 to 186.96.95.254186.96.95.255126
193186.96.96.0/25186.96.96.1 to 186.96.96.126186.96.96.127126
194186.96.96.128/25186.96.96.129 to 186.96.96.254186.96.96.255126
195186.96.97.0/25186.96.97.1 to 186.96.97.126186.96.97.127126
196186.96.97.128/25186.96.97.129 to 186.96.97.254186.96.97.255126
197186.96.98.0/25186.96.98.1 to 186.96.98.126186.96.98.127126
198186.96.98.128/25186.96.98.129 to 186.96.98.254186.96.98.255126
199186.96.99.0/25186.96.99.1 to 186.96.99.126186.96.99.127126
200186.96.99.128/25186.96.99.129 to 186.96.99.254186.96.99.255126
201186.96.100.0/25186.96.100.1 to 186.96.100.126186.96.100.127126
202186.96.100.128/25186.96.100.129 to 186.96.100.254186.96.100.255126
203186.96.101.0/25186.96.101.1 to 186.96.101.126186.96.101.127126
204186.96.101.128/25186.96.101.129 to 186.96.101.254186.96.101.255126
205186.96.102.0/25186.96.102.1 to 186.96.102.126186.96.102.127126
206186.96.102.128/25186.96.102.129 to 186.96.102.254186.96.102.255126
207186.96.103.0/25186.96.103.1 to 186.96.103.126186.96.103.127126
208186.96.103.128/25186.96.103.129 to 186.96.103.254186.96.103.255126
209186.96.104.0/25186.96.104.1 to 186.96.104.126186.96.104.127126
210186.96.104.128/25186.96.104.129 to 186.96.104.254186.96.104.255126
211186.96.105.0/25186.96.105.1 to 186.96.105.126186.96.105.127126
212186.96.105.128/25186.96.105.129 to 186.96.105.254186.96.105.255126
213186.96.106.0/25186.96.106.1 to 186.96.106.126186.96.106.127126
214186.96.106.128/25186.96.106.129 to 186.96.106.254186.96.106.255126
215186.96.107.0/25186.96.107.1 to 186.96.107.126186.96.107.127126
216186.96.107.128/25186.96.107.129 to 186.96.107.254186.96.107.255126
217186.96.108.0/25186.96.108.1 to 186.96.108.126186.96.108.127126
218186.96.108.128/25186.96.108.129 to 186.96.108.254186.96.108.255126
219186.96.109.0/25186.96.109.1 to 186.96.109.126186.96.109.127126
220186.96.109.128/25186.96.109.129 to 186.96.109.254186.96.109.255126
221186.96.110.0/25186.96.110.1 to 186.96.110.126186.96.110.127126
222186.96.110.128/25186.96.110.129 to 186.96.110.254186.96.110.255126
223186.96.111.0/25186.96.111.1 to 186.96.111.126186.96.111.127126
224186.96.111.128/25186.96.111.129 to 186.96.111.254186.96.111.255126
225186.96.112.0/25186.96.112.1 to 186.96.112.126186.96.112.127126
226186.96.112.128/25186.96.112.129 to 186.96.112.254186.96.112.255126
227186.96.113.0/25186.96.113.1 to 186.96.113.126186.96.113.127126
228186.96.113.128/25186.96.113.129 to 186.96.113.254186.96.113.255126
229186.96.114.0/25186.96.114.1 to 186.96.114.126186.96.114.127126
230186.96.114.128/25186.96.114.129 to 186.96.114.254186.96.114.255126
231186.96.115.0/25186.96.115.1 to 186.96.115.126186.96.115.127126
232186.96.115.128/25186.96.115.129 to 186.96.115.254186.96.115.255126
233186.96.116.0/25186.96.116.1 to 186.96.116.126186.96.116.127126
234186.96.116.128/25186.96.116.129 to 186.96.116.254186.96.116.255126
235186.96.117.0/25186.96.117.1 to 186.96.117.126186.96.117.127126
236186.96.117.128/25186.96.117.129 to 186.96.117.254186.96.117.255126
237186.96.118.0/25186.96.118.1 to 186.96.118.126186.96.118.127126
238186.96.118.128/25186.96.118.129 to 186.96.118.254186.96.118.255126
239186.96.119.0/25186.96.119.1 to 186.96.119.126186.96.119.127126
240186.96.119.128/25186.96.119.129 to 186.96.119.254186.96.119.255126
241186.96.120.0/25186.96.120.1 to 186.96.120.126186.96.120.127126
242186.96.120.128/25186.96.120.129 to 186.96.120.254186.96.120.255126
243186.96.121.0/25186.96.121.1 to 186.96.121.126186.96.121.127126
244186.96.121.128/25186.96.121.129 to 186.96.121.254186.96.121.255126
245186.96.122.0/25186.96.122.1 to 186.96.122.126186.96.122.127126
246186.96.122.128/25186.96.122.129 to 186.96.122.254186.96.122.255126
247186.96.123.0/25186.96.123.1 to 186.96.123.126186.96.123.127126
248186.96.123.128/25186.96.123.129 to 186.96.123.254186.96.123.255126
249186.96.124.0/25186.96.124.1 to 186.96.124.126186.96.124.127126
250186.96.124.128/25186.96.124.129 to 186.96.124.254186.96.124.255126
251186.96.125.0/25186.96.125.1 to 186.96.125.126186.96.125.127126
252186.96.125.128/25186.96.125.129 to 186.96.125.254186.96.125.255126
253186.96.126.0/25186.96.126.1 to 186.96.126.126186.96.126.127126
254186.96.126.128/25186.96.126.129 to 186.96.126.254186.96.126.255126
255186.96.127.0/25186.96.127.1 to 186.96.127.126186.96.127.127126
256186.96.127.128/25186.96.127.129 to 186.96.127.254186.96.127.255126

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.