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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.

Network114.7.0.0/16
Usable hosts65,534
Subnet mask255.255.0.0
Addresses65,536
Network address
114.7.0.0
Broadcast address
114.7.255.255
First usable
114.7.0.1
Last usable
114.7.255.254
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
A (default /8)
As numbers
Hex 72070000 · Integer 1913061376 to 1913126911
Reverse DNS zone
7.114.in-addr.arpa
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address01110010.00000111..00000000.00000000114.7.0.0
Subnet mask11111111.11111111..00000000.00000000255.255.0.0
Network01110010.00000111..00000000.00000000114.7.0.0
Broadcast01110010.00000111..11111111.11111111114.7.255.255
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)

114.7.0.0/16 makes 1,024 subnets of /26; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
1114.7.0.0/26114.7.0.1 to 114.7.0.62114.7.0.6362
2114.7.0.64/26114.7.0.65 to 114.7.0.126114.7.0.12762
3114.7.0.128/26114.7.0.129 to 114.7.0.190114.7.0.19162
4114.7.0.192/26114.7.0.193 to 114.7.0.254114.7.0.25562
5114.7.1.0/26114.7.1.1 to 114.7.1.62114.7.1.6362
6114.7.1.64/26114.7.1.65 to 114.7.1.126114.7.1.12762
7114.7.1.128/26114.7.1.129 to 114.7.1.190114.7.1.19162
8114.7.1.192/26114.7.1.193 to 114.7.1.254114.7.1.25562
9114.7.2.0/26114.7.2.1 to 114.7.2.62114.7.2.6362
10114.7.2.64/26114.7.2.65 to 114.7.2.126114.7.2.12762
11114.7.2.128/26114.7.2.129 to 114.7.2.190114.7.2.19162
12114.7.2.192/26114.7.2.193 to 114.7.2.254114.7.2.25562
13114.7.3.0/26114.7.3.1 to 114.7.3.62114.7.3.6362
14114.7.3.64/26114.7.3.65 to 114.7.3.126114.7.3.12762
15114.7.3.128/26114.7.3.129 to 114.7.3.190114.7.3.19162
16114.7.3.192/26114.7.3.193 to 114.7.3.254114.7.3.25562
17114.7.4.0/26114.7.4.1 to 114.7.4.62114.7.4.6362
18114.7.4.64/26114.7.4.65 to 114.7.4.126114.7.4.12762
19114.7.4.128/26114.7.4.129 to 114.7.4.190114.7.4.19162
20114.7.4.192/26114.7.4.193 to 114.7.4.254114.7.4.25562
21114.7.5.0/26114.7.5.1 to 114.7.5.62114.7.5.6362
22114.7.5.64/26114.7.5.65 to 114.7.5.126114.7.5.12762
23114.7.5.128/26114.7.5.129 to 114.7.5.190114.7.5.19162
24114.7.5.192/26114.7.5.193 to 114.7.5.254114.7.5.25562
25114.7.6.0/26114.7.6.1 to 114.7.6.62114.7.6.6362
26114.7.6.64/26114.7.6.65 to 114.7.6.126114.7.6.12762
27114.7.6.128/26114.7.6.129 to 114.7.6.190114.7.6.19162
28114.7.6.192/26114.7.6.193 to 114.7.6.254114.7.6.25562
29114.7.7.0/26114.7.7.1 to 114.7.7.62114.7.7.6362
30114.7.7.64/26114.7.7.65 to 114.7.7.126114.7.7.12762
31114.7.7.128/26114.7.7.129 to 114.7.7.190114.7.7.19162
32114.7.7.192/26114.7.7.193 to 114.7.7.254114.7.7.25562
33114.7.8.0/26114.7.8.1 to 114.7.8.62114.7.8.6362
34114.7.8.64/26114.7.8.65 to 114.7.8.126114.7.8.12762
35114.7.8.128/26114.7.8.129 to 114.7.8.190114.7.8.19162
36114.7.8.192/26114.7.8.193 to 114.7.8.254114.7.8.25562
37114.7.9.0/26114.7.9.1 to 114.7.9.62114.7.9.6362
38114.7.9.64/26114.7.9.65 to 114.7.9.126114.7.9.12762
39114.7.9.128/26114.7.9.129 to 114.7.9.190114.7.9.19162
40114.7.9.192/26114.7.9.193 to 114.7.9.254114.7.9.25562
41114.7.10.0/26114.7.10.1 to 114.7.10.62114.7.10.6362
42114.7.10.64/26114.7.10.65 to 114.7.10.126114.7.10.12762
43114.7.10.128/26114.7.10.129 to 114.7.10.190114.7.10.19162
44114.7.10.192/26114.7.10.193 to 114.7.10.254114.7.10.25562
45114.7.11.0/26114.7.11.1 to 114.7.11.62114.7.11.6362
46114.7.11.64/26114.7.11.65 to 114.7.11.126114.7.11.12762
47114.7.11.128/26114.7.11.129 to 114.7.11.190114.7.11.19162
48114.7.11.192/26114.7.11.193 to 114.7.11.254114.7.11.25562
49114.7.12.0/26114.7.12.1 to 114.7.12.62114.7.12.6362
50114.7.12.64/26114.7.12.65 to 114.7.12.126114.7.12.12762
51114.7.12.128/26114.7.12.129 to 114.7.12.190114.7.12.19162
52114.7.12.192/26114.7.12.193 to 114.7.12.254114.7.12.25562
53114.7.13.0/26114.7.13.1 to 114.7.13.62114.7.13.6362
54114.7.13.64/26114.7.13.65 to 114.7.13.126114.7.13.12762
55114.7.13.128/26114.7.13.129 to 114.7.13.190114.7.13.19162
56114.7.13.192/26114.7.13.193 to 114.7.13.254114.7.13.25562
57114.7.14.0/26114.7.14.1 to 114.7.14.62114.7.14.6362
58114.7.14.64/26114.7.14.65 to 114.7.14.126114.7.14.12762
59114.7.14.128/26114.7.14.129 to 114.7.14.190114.7.14.19162
60114.7.14.192/26114.7.14.193 to 114.7.14.254114.7.14.25562
61114.7.15.0/26114.7.15.1 to 114.7.15.62114.7.15.6362
62114.7.15.64/26114.7.15.65 to 114.7.15.126114.7.15.12762
63114.7.15.128/26114.7.15.129 to 114.7.15.190114.7.15.19162
64114.7.15.192/26114.7.15.193 to 114.7.15.254114.7.15.25562
65114.7.16.0/26114.7.16.1 to 114.7.16.62114.7.16.6362
66114.7.16.64/26114.7.16.65 to 114.7.16.126114.7.16.12762
67114.7.16.128/26114.7.16.129 to 114.7.16.190114.7.16.19162
68114.7.16.192/26114.7.16.193 to 114.7.16.254114.7.16.25562
69114.7.17.0/26114.7.17.1 to 114.7.17.62114.7.17.6362
70114.7.17.64/26114.7.17.65 to 114.7.17.126114.7.17.12762
71114.7.17.128/26114.7.17.129 to 114.7.17.190114.7.17.19162
72114.7.17.192/26114.7.17.193 to 114.7.17.254114.7.17.25562
73114.7.18.0/26114.7.18.1 to 114.7.18.62114.7.18.6362
74114.7.18.64/26114.7.18.65 to 114.7.18.126114.7.18.12762
75114.7.18.128/26114.7.18.129 to 114.7.18.190114.7.18.19162
76114.7.18.192/26114.7.18.193 to 114.7.18.254114.7.18.25562
77114.7.19.0/26114.7.19.1 to 114.7.19.62114.7.19.6362
78114.7.19.64/26114.7.19.65 to 114.7.19.126114.7.19.12762
79114.7.19.128/26114.7.19.129 to 114.7.19.190114.7.19.19162
80114.7.19.192/26114.7.19.193 to 114.7.19.254114.7.19.25562
81114.7.20.0/26114.7.20.1 to 114.7.20.62114.7.20.6362
82114.7.20.64/26114.7.20.65 to 114.7.20.126114.7.20.12762
83114.7.20.128/26114.7.20.129 to 114.7.20.190114.7.20.19162
84114.7.20.192/26114.7.20.193 to 114.7.20.254114.7.20.25562
85114.7.21.0/26114.7.21.1 to 114.7.21.62114.7.21.6362
86114.7.21.64/26114.7.21.65 to 114.7.21.126114.7.21.12762
87114.7.21.128/26114.7.21.129 to 114.7.21.190114.7.21.19162
88114.7.21.192/26114.7.21.193 to 114.7.21.254114.7.21.25562
89114.7.22.0/26114.7.22.1 to 114.7.22.62114.7.22.6362
90114.7.22.64/26114.7.22.65 to 114.7.22.126114.7.22.12762
91114.7.22.128/26114.7.22.129 to 114.7.22.190114.7.22.19162
92114.7.22.192/26114.7.22.193 to 114.7.22.254114.7.22.25562
93114.7.23.0/26114.7.23.1 to 114.7.23.62114.7.23.6362
94114.7.23.64/26114.7.23.65 to 114.7.23.126114.7.23.12762
95114.7.23.128/26114.7.23.129 to 114.7.23.190114.7.23.19162
96114.7.23.192/26114.7.23.193 to 114.7.23.254114.7.23.25562
97114.7.24.0/26114.7.24.1 to 114.7.24.62114.7.24.6362
98114.7.24.64/26114.7.24.65 to 114.7.24.126114.7.24.12762
99114.7.24.128/26114.7.24.129 to 114.7.24.190114.7.24.19162
100114.7.24.192/26114.7.24.193 to 114.7.24.254114.7.24.25562
101114.7.25.0/26114.7.25.1 to 114.7.25.62114.7.25.6362
102114.7.25.64/26114.7.25.65 to 114.7.25.126114.7.25.12762
103114.7.25.128/26114.7.25.129 to 114.7.25.190114.7.25.19162
104114.7.25.192/26114.7.25.193 to 114.7.25.254114.7.25.25562
105114.7.26.0/26114.7.26.1 to 114.7.26.62114.7.26.6362
106114.7.26.64/26114.7.26.65 to 114.7.26.126114.7.26.12762
107114.7.26.128/26114.7.26.129 to 114.7.26.190114.7.26.19162
108114.7.26.192/26114.7.26.193 to 114.7.26.254114.7.26.25562
109114.7.27.0/26114.7.27.1 to 114.7.27.62114.7.27.6362
110114.7.27.64/26114.7.27.65 to 114.7.27.126114.7.27.12762
111114.7.27.128/26114.7.27.129 to 114.7.27.190114.7.27.19162
112114.7.27.192/26114.7.27.193 to 114.7.27.254114.7.27.25562
113114.7.28.0/26114.7.28.1 to 114.7.28.62114.7.28.6362
114114.7.28.64/26114.7.28.65 to 114.7.28.126114.7.28.12762
115114.7.28.128/26114.7.28.129 to 114.7.28.190114.7.28.19162
116114.7.28.192/26114.7.28.193 to 114.7.28.254114.7.28.25562
117114.7.29.0/26114.7.29.1 to 114.7.29.62114.7.29.6362
118114.7.29.64/26114.7.29.65 to 114.7.29.126114.7.29.12762
119114.7.29.128/26114.7.29.129 to 114.7.29.190114.7.29.19162
120114.7.29.192/26114.7.29.193 to 114.7.29.254114.7.29.25562
121114.7.30.0/26114.7.30.1 to 114.7.30.62114.7.30.6362
122114.7.30.64/26114.7.30.65 to 114.7.30.126114.7.30.12762
123114.7.30.128/26114.7.30.129 to 114.7.30.190114.7.30.19162
124114.7.30.192/26114.7.30.193 to 114.7.30.254114.7.30.25562
125114.7.31.0/26114.7.31.1 to 114.7.31.62114.7.31.6362
126114.7.31.64/26114.7.31.65 to 114.7.31.126114.7.31.12762
127114.7.31.128/26114.7.31.129 to 114.7.31.190114.7.31.19162
128114.7.31.192/26114.7.31.193 to 114.7.31.254114.7.31.25562
129114.7.32.0/26114.7.32.1 to 114.7.32.62114.7.32.6362
130114.7.32.64/26114.7.32.65 to 114.7.32.126114.7.32.12762
131114.7.32.128/26114.7.32.129 to 114.7.32.190114.7.32.19162
132114.7.32.192/26114.7.32.193 to 114.7.32.254114.7.32.25562
133114.7.33.0/26114.7.33.1 to 114.7.33.62114.7.33.6362
134114.7.33.64/26114.7.33.65 to 114.7.33.126114.7.33.12762
135114.7.33.128/26114.7.33.129 to 114.7.33.190114.7.33.19162
136114.7.33.192/26114.7.33.193 to 114.7.33.254114.7.33.25562
137114.7.34.0/26114.7.34.1 to 114.7.34.62114.7.34.6362
138114.7.34.64/26114.7.34.65 to 114.7.34.126114.7.34.12762
139114.7.34.128/26114.7.34.129 to 114.7.34.190114.7.34.19162
140114.7.34.192/26114.7.34.193 to 114.7.34.254114.7.34.25562
141114.7.35.0/26114.7.35.1 to 114.7.35.62114.7.35.6362
142114.7.35.64/26114.7.35.65 to 114.7.35.126114.7.35.12762
143114.7.35.128/26114.7.35.129 to 114.7.35.190114.7.35.19162
144114.7.35.192/26114.7.35.193 to 114.7.35.254114.7.35.25562
145114.7.36.0/26114.7.36.1 to 114.7.36.62114.7.36.6362
146114.7.36.64/26114.7.36.65 to 114.7.36.126114.7.36.12762
147114.7.36.128/26114.7.36.129 to 114.7.36.190114.7.36.19162
148114.7.36.192/26114.7.36.193 to 114.7.36.254114.7.36.25562
149114.7.37.0/26114.7.37.1 to 114.7.37.62114.7.37.6362
150114.7.37.64/26114.7.37.65 to 114.7.37.126114.7.37.12762
151114.7.37.128/26114.7.37.129 to 114.7.37.190114.7.37.19162
152114.7.37.192/26114.7.37.193 to 114.7.37.254114.7.37.25562
153114.7.38.0/26114.7.38.1 to 114.7.38.62114.7.38.6362
154114.7.38.64/26114.7.38.65 to 114.7.38.126114.7.38.12762
155114.7.38.128/26114.7.38.129 to 114.7.38.190114.7.38.19162
156114.7.38.192/26114.7.38.193 to 114.7.38.254114.7.38.25562
157114.7.39.0/26114.7.39.1 to 114.7.39.62114.7.39.6362
158114.7.39.64/26114.7.39.65 to 114.7.39.126114.7.39.12762
159114.7.39.128/26114.7.39.129 to 114.7.39.190114.7.39.19162
160114.7.39.192/26114.7.39.193 to 114.7.39.254114.7.39.25562
161114.7.40.0/26114.7.40.1 to 114.7.40.62114.7.40.6362
162114.7.40.64/26114.7.40.65 to 114.7.40.126114.7.40.12762
163114.7.40.128/26114.7.40.129 to 114.7.40.190114.7.40.19162
164114.7.40.192/26114.7.40.193 to 114.7.40.254114.7.40.25562
165114.7.41.0/26114.7.41.1 to 114.7.41.62114.7.41.6362
166114.7.41.64/26114.7.41.65 to 114.7.41.126114.7.41.12762
167114.7.41.128/26114.7.41.129 to 114.7.41.190114.7.41.19162
168114.7.41.192/26114.7.41.193 to 114.7.41.254114.7.41.25562
169114.7.42.0/26114.7.42.1 to 114.7.42.62114.7.42.6362
170114.7.42.64/26114.7.42.65 to 114.7.42.126114.7.42.12762
171114.7.42.128/26114.7.42.129 to 114.7.42.190114.7.42.19162
172114.7.42.192/26114.7.42.193 to 114.7.42.254114.7.42.25562
173114.7.43.0/26114.7.43.1 to 114.7.43.62114.7.43.6362
174114.7.43.64/26114.7.43.65 to 114.7.43.126114.7.43.12762
175114.7.43.128/26114.7.43.129 to 114.7.43.190114.7.43.19162
176114.7.43.192/26114.7.43.193 to 114.7.43.254114.7.43.25562
177114.7.44.0/26114.7.44.1 to 114.7.44.62114.7.44.6362
178114.7.44.64/26114.7.44.65 to 114.7.44.126114.7.44.12762
179114.7.44.128/26114.7.44.129 to 114.7.44.190114.7.44.19162
180114.7.44.192/26114.7.44.193 to 114.7.44.254114.7.44.25562
181114.7.45.0/26114.7.45.1 to 114.7.45.62114.7.45.6362
182114.7.45.64/26114.7.45.65 to 114.7.45.126114.7.45.12762
183114.7.45.128/26114.7.45.129 to 114.7.45.190114.7.45.19162
184114.7.45.192/26114.7.45.193 to 114.7.45.254114.7.45.25562
185114.7.46.0/26114.7.46.1 to 114.7.46.62114.7.46.6362
186114.7.46.64/26114.7.46.65 to 114.7.46.126114.7.46.12762
187114.7.46.128/26114.7.46.129 to 114.7.46.190114.7.46.19162
188114.7.46.192/26114.7.46.193 to 114.7.46.254114.7.46.25562
189114.7.47.0/26114.7.47.1 to 114.7.47.62114.7.47.6362
190114.7.47.64/26114.7.47.65 to 114.7.47.126114.7.47.12762
191114.7.47.128/26114.7.47.129 to 114.7.47.190114.7.47.19162
192114.7.47.192/26114.7.47.193 to 114.7.47.254114.7.47.25562
193114.7.48.0/26114.7.48.1 to 114.7.48.62114.7.48.6362
194114.7.48.64/26114.7.48.65 to 114.7.48.126114.7.48.12762
195114.7.48.128/26114.7.48.129 to 114.7.48.190114.7.48.19162
196114.7.48.192/26114.7.48.193 to 114.7.48.254114.7.48.25562
197114.7.49.0/26114.7.49.1 to 114.7.49.62114.7.49.6362
198114.7.49.64/26114.7.49.65 to 114.7.49.126114.7.49.12762
199114.7.49.128/26114.7.49.129 to 114.7.49.190114.7.49.19162
200114.7.49.192/26114.7.49.193 to 114.7.49.254114.7.49.25562
201114.7.50.0/26114.7.50.1 to 114.7.50.62114.7.50.6362
202114.7.50.64/26114.7.50.65 to 114.7.50.126114.7.50.12762
203114.7.50.128/26114.7.50.129 to 114.7.50.190114.7.50.19162
204114.7.50.192/26114.7.50.193 to 114.7.50.254114.7.50.25562
205114.7.51.0/26114.7.51.1 to 114.7.51.62114.7.51.6362
206114.7.51.64/26114.7.51.65 to 114.7.51.126114.7.51.12762
207114.7.51.128/26114.7.51.129 to 114.7.51.190114.7.51.19162
208114.7.51.192/26114.7.51.193 to 114.7.51.254114.7.51.25562
209114.7.52.0/26114.7.52.1 to 114.7.52.62114.7.52.6362
210114.7.52.64/26114.7.52.65 to 114.7.52.126114.7.52.12762
211114.7.52.128/26114.7.52.129 to 114.7.52.190114.7.52.19162
212114.7.52.192/26114.7.52.193 to 114.7.52.254114.7.52.25562
213114.7.53.0/26114.7.53.1 to 114.7.53.62114.7.53.6362
214114.7.53.64/26114.7.53.65 to 114.7.53.126114.7.53.12762
215114.7.53.128/26114.7.53.129 to 114.7.53.190114.7.53.19162
216114.7.53.192/26114.7.53.193 to 114.7.53.254114.7.53.25562
217114.7.54.0/26114.7.54.1 to 114.7.54.62114.7.54.6362
218114.7.54.64/26114.7.54.65 to 114.7.54.126114.7.54.12762
219114.7.54.128/26114.7.54.129 to 114.7.54.190114.7.54.19162
220114.7.54.192/26114.7.54.193 to 114.7.54.254114.7.54.25562
221114.7.55.0/26114.7.55.1 to 114.7.55.62114.7.55.6362
222114.7.55.64/26114.7.55.65 to 114.7.55.126114.7.55.12762
223114.7.55.128/26114.7.55.129 to 114.7.55.190114.7.55.19162
224114.7.55.192/26114.7.55.193 to 114.7.55.254114.7.55.25562
225114.7.56.0/26114.7.56.1 to 114.7.56.62114.7.56.6362
226114.7.56.64/26114.7.56.65 to 114.7.56.126114.7.56.12762
227114.7.56.128/26114.7.56.129 to 114.7.56.190114.7.56.19162
228114.7.56.192/26114.7.56.193 to 114.7.56.254114.7.56.25562
229114.7.57.0/26114.7.57.1 to 114.7.57.62114.7.57.6362
230114.7.57.64/26114.7.57.65 to 114.7.57.126114.7.57.12762
231114.7.57.128/26114.7.57.129 to 114.7.57.190114.7.57.19162
232114.7.57.192/26114.7.57.193 to 114.7.57.254114.7.57.25562
233114.7.58.0/26114.7.58.1 to 114.7.58.62114.7.58.6362
234114.7.58.64/26114.7.58.65 to 114.7.58.126114.7.58.12762
235114.7.58.128/26114.7.58.129 to 114.7.58.190114.7.58.19162
236114.7.58.192/26114.7.58.193 to 114.7.58.254114.7.58.25562
237114.7.59.0/26114.7.59.1 to 114.7.59.62114.7.59.6362
238114.7.59.64/26114.7.59.65 to 114.7.59.126114.7.59.12762
239114.7.59.128/26114.7.59.129 to 114.7.59.190114.7.59.19162
240114.7.59.192/26114.7.59.193 to 114.7.59.254114.7.59.25562
241114.7.60.0/26114.7.60.1 to 114.7.60.62114.7.60.6362
242114.7.60.64/26114.7.60.65 to 114.7.60.126114.7.60.12762
243114.7.60.128/26114.7.60.129 to 114.7.60.190114.7.60.19162
244114.7.60.192/26114.7.60.193 to 114.7.60.254114.7.60.25562
245114.7.61.0/26114.7.61.1 to 114.7.61.62114.7.61.6362
246114.7.61.64/26114.7.61.65 to 114.7.61.126114.7.61.12762
247114.7.61.128/26114.7.61.129 to 114.7.61.190114.7.61.19162
248114.7.61.192/26114.7.61.193 to 114.7.61.254114.7.61.25562
249114.7.62.0/26114.7.62.1 to 114.7.62.62114.7.62.6362
250114.7.62.64/26114.7.62.65 to 114.7.62.126114.7.62.12762
251114.7.62.128/26114.7.62.129 to 114.7.62.190114.7.62.19162
252114.7.62.192/26114.7.62.193 to 114.7.62.254114.7.62.25562
253114.7.63.0/26114.7.63.1 to 114.7.63.62114.7.63.6362
254114.7.63.64/26114.7.63.65 to 114.7.63.126114.7.63.12762
255114.7.63.128/26114.7.63.129 to 114.7.63.190114.7.63.19162
256114.7.63.192/26114.7.63.193 to 114.7.63.254114.7.63.25562

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.