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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.

Network152.60.0.0/16
Usable hosts65,534
Subnet mask255.255.0.0
Addresses65,536
Network address
152.60.0.0
Broadcast address
152.60.255.255
First usable
152.60.0.1
Last usable
152.60.255.254
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 983C0000 · Integer 2554068992 to 2554134527
Reverse DNS zone
60.152.in-addr.arpa
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address10011000.00111100..00000000.00000000152.60.0.0
Subnet mask11111111.11111111..00000000.00000000255.255.0.0
Network10011000.00111100..00000000.00000000152.60.0.0
Broadcast10011000.00111100..11111111.11111111152.60.255.255
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)

152.60.0.0/16 makes 1,024 subnets of /26; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
1152.60.0.0/26152.60.0.1 to 152.60.0.62152.60.0.6362
2152.60.0.64/26152.60.0.65 to 152.60.0.126152.60.0.12762
3152.60.0.128/26152.60.0.129 to 152.60.0.190152.60.0.19162
4152.60.0.192/26152.60.0.193 to 152.60.0.254152.60.0.25562
5152.60.1.0/26152.60.1.1 to 152.60.1.62152.60.1.6362
6152.60.1.64/26152.60.1.65 to 152.60.1.126152.60.1.12762
7152.60.1.128/26152.60.1.129 to 152.60.1.190152.60.1.19162
8152.60.1.192/26152.60.1.193 to 152.60.1.254152.60.1.25562
9152.60.2.0/26152.60.2.1 to 152.60.2.62152.60.2.6362
10152.60.2.64/26152.60.2.65 to 152.60.2.126152.60.2.12762
11152.60.2.128/26152.60.2.129 to 152.60.2.190152.60.2.19162
12152.60.2.192/26152.60.2.193 to 152.60.2.254152.60.2.25562
13152.60.3.0/26152.60.3.1 to 152.60.3.62152.60.3.6362
14152.60.3.64/26152.60.3.65 to 152.60.3.126152.60.3.12762
15152.60.3.128/26152.60.3.129 to 152.60.3.190152.60.3.19162
16152.60.3.192/26152.60.3.193 to 152.60.3.254152.60.3.25562
17152.60.4.0/26152.60.4.1 to 152.60.4.62152.60.4.6362
18152.60.4.64/26152.60.4.65 to 152.60.4.126152.60.4.12762
19152.60.4.128/26152.60.4.129 to 152.60.4.190152.60.4.19162
20152.60.4.192/26152.60.4.193 to 152.60.4.254152.60.4.25562
21152.60.5.0/26152.60.5.1 to 152.60.5.62152.60.5.6362
22152.60.5.64/26152.60.5.65 to 152.60.5.126152.60.5.12762
23152.60.5.128/26152.60.5.129 to 152.60.5.190152.60.5.19162
24152.60.5.192/26152.60.5.193 to 152.60.5.254152.60.5.25562
25152.60.6.0/26152.60.6.1 to 152.60.6.62152.60.6.6362
26152.60.6.64/26152.60.6.65 to 152.60.6.126152.60.6.12762
27152.60.6.128/26152.60.6.129 to 152.60.6.190152.60.6.19162
28152.60.6.192/26152.60.6.193 to 152.60.6.254152.60.6.25562
29152.60.7.0/26152.60.7.1 to 152.60.7.62152.60.7.6362
30152.60.7.64/26152.60.7.65 to 152.60.7.126152.60.7.12762
31152.60.7.128/26152.60.7.129 to 152.60.7.190152.60.7.19162
32152.60.7.192/26152.60.7.193 to 152.60.7.254152.60.7.25562
33152.60.8.0/26152.60.8.1 to 152.60.8.62152.60.8.6362
34152.60.8.64/26152.60.8.65 to 152.60.8.126152.60.8.12762
35152.60.8.128/26152.60.8.129 to 152.60.8.190152.60.8.19162
36152.60.8.192/26152.60.8.193 to 152.60.8.254152.60.8.25562
37152.60.9.0/26152.60.9.1 to 152.60.9.62152.60.9.6362
38152.60.9.64/26152.60.9.65 to 152.60.9.126152.60.9.12762
39152.60.9.128/26152.60.9.129 to 152.60.9.190152.60.9.19162
40152.60.9.192/26152.60.9.193 to 152.60.9.254152.60.9.25562
41152.60.10.0/26152.60.10.1 to 152.60.10.62152.60.10.6362
42152.60.10.64/26152.60.10.65 to 152.60.10.126152.60.10.12762
43152.60.10.128/26152.60.10.129 to 152.60.10.190152.60.10.19162
44152.60.10.192/26152.60.10.193 to 152.60.10.254152.60.10.25562
45152.60.11.0/26152.60.11.1 to 152.60.11.62152.60.11.6362
46152.60.11.64/26152.60.11.65 to 152.60.11.126152.60.11.12762
47152.60.11.128/26152.60.11.129 to 152.60.11.190152.60.11.19162
48152.60.11.192/26152.60.11.193 to 152.60.11.254152.60.11.25562
49152.60.12.0/26152.60.12.1 to 152.60.12.62152.60.12.6362
50152.60.12.64/26152.60.12.65 to 152.60.12.126152.60.12.12762
51152.60.12.128/26152.60.12.129 to 152.60.12.190152.60.12.19162
52152.60.12.192/26152.60.12.193 to 152.60.12.254152.60.12.25562
53152.60.13.0/26152.60.13.1 to 152.60.13.62152.60.13.6362
54152.60.13.64/26152.60.13.65 to 152.60.13.126152.60.13.12762
55152.60.13.128/26152.60.13.129 to 152.60.13.190152.60.13.19162
56152.60.13.192/26152.60.13.193 to 152.60.13.254152.60.13.25562
57152.60.14.0/26152.60.14.1 to 152.60.14.62152.60.14.6362
58152.60.14.64/26152.60.14.65 to 152.60.14.126152.60.14.12762
59152.60.14.128/26152.60.14.129 to 152.60.14.190152.60.14.19162
60152.60.14.192/26152.60.14.193 to 152.60.14.254152.60.14.25562
61152.60.15.0/26152.60.15.1 to 152.60.15.62152.60.15.6362
62152.60.15.64/26152.60.15.65 to 152.60.15.126152.60.15.12762
63152.60.15.128/26152.60.15.129 to 152.60.15.190152.60.15.19162
64152.60.15.192/26152.60.15.193 to 152.60.15.254152.60.15.25562
65152.60.16.0/26152.60.16.1 to 152.60.16.62152.60.16.6362
66152.60.16.64/26152.60.16.65 to 152.60.16.126152.60.16.12762
67152.60.16.128/26152.60.16.129 to 152.60.16.190152.60.16.19162
68152.60.16.192/26152.60.16.193 to 152.60.16.254152.60.16.25562
69152.60.17.0/26152.60.17.1 to 152.60.17.62152.60.17.6362
70152.60.17.64/26152.60.17.65 to 152.60.17.126152.60.17.12762
71152.60.17.128/26152.60.17.129 to 152.60.17.190152.60.17.19162
72152.60.17.192/26152.60.17.193 to 152.60.17.254152.60.17.25562
73152.60.18.0/26152.60.18.1 to 152.60.18.62152.60.18.6362
74152.60.18.64/26152.60.18.65 to 152.60.18.126152.60.18.12762
75152.60.18.128/26152.60.18.129 to 152.60.18.190152.60.18.19162
76152.60.18.192/26152.60.18.193 to 152.60.18.254152.60.18.25562
77152.60.19.0/26152.60.19.1 to 152.60.19.62152.60.19.6362
78152.60.19.64/26152.60.19.65 to 152.60.19.126152.60.19.12762
79152.60.19.128/26152.60.19.129 to 152.60.19.190152.60.19.19162
80152.60.19.192/26152.60.19.193 to 152.60.19.254152.60.19.25562
81152.60.20.0/26152.60.20.1 to 152.60.20.62152.60.20.6362
82152.60.20.64/26152.60.20.65 to 152.60.20.126152.60.20.12762
83152.60.20.128/26152.60.20.129 to 152.60.20.190152.60.20.19162
84152.60.20.192/26152.60.20.193 to 152.60.20.254152.60.20.25562
85152.60.21.0/26152.60.21.1 to 152.60.21.62152.60.21.6362
86152.60.21.64/26152.60.21.65 to 152.60.21.126152.60.21.12762
87152.60.21.128/26152.60.21.129 to 152.60.21.190152.60.21.19162
88152.60.21.192/26152.60.21.193 to 152.60.21.254152.60.21.25562
89152.60.22.0/26152.60.22.1 to 152.60.22.62152.60.22.6362
90152.60.22.64/26152.60.22.65 to 152.60.22.126152.60.22.12762
91152.60.22.128/26152.60.22.129 to 152.60.22.190152.60.22.19162
92152.60.22.192/26152.60.22.193 to 152.60.22.254152.60.22.25562
93152.60.23.0/26152.60.23.1 to 152.60.23.62152.60.23.6362
94152.60.23.64/26152.60.23.65 to 152.60.23.126152.60.23.12762
95152.60.23.128/26152.60.23.129 to 152.60.23.190152.60.23.19162
96152.60.23.192/26152.60.23.193 to 152.60.23.254152.60.23.25562
97152.60.24.0/26152.60.24.1 to 152.60.24.62152.60.24.6362
98152.60.24.64/26152.60.24.65 to 152.60.24.126152.60.24.12762
99152.60.24.128/26152.60.24.129 to 152.60.24.190152.60.24.19162
100152.60.24.192/26152.60.24.193 to 152.60.24.254152.60.24.25562
101152.60.25.0/26152.60.25.1 to 152.60.25.62152.60.25.6362
102152.60.25.64/26152.60.25.65 to 152.60.25.126152.60.25.12762
103152.60.25.128/26152.60.25.129 to 152.60.25.190152.60.25.19162
104152.60.25.192/26152.60.25.193 to 152.60.25.254152.60.25.25562
105152.60.26.0/26152.60.26.1 to 152.60.26.62152.60.26.6362
106152.60.26.64/26152.60.26.65 to 152.60.26.126152.60.26.12762
107152.60.26.128/26152.60.26.129 to 152.60.26.190152.60.26.19162
108152.60.26.192/26152.60.26.193 to 152.60.26.254152.60.26.25562
109152.60.27.0/26152.60.27.1 to 152.60.27.62152.60.27.6362
110152.60.27.64/26152.60.27.65 to 152.60.27.126152.60.27.12762
111152.60.27.128/26152.60.27.129 to 152.60.27.190152.60.27.19162
112152.60.27.192/26152.60.27.193 to 152.60.27.254152.60.27.25562
113152.60.28.0/26152.60.28.1 to 152.60.28.62152.60.28.6362
114152.60.28.64/26152.60.28.65 to 152.60.28.126152.60.28.12762
115152.60.28.128/26152.60.28.129 to 152.60.28.190152.60.28.19162
116152.60.28.192/26152.60.28.193 to 152.60.28.254152.60.28.25562
117152.60.29.0/26152.60.29.1 to 152.60.29.62152.60.29.6362
118152.60.29.64/26152.60.29.65 to 152.60.29.126152.60.29.12762
119152.60.29.128/26152.60.29.129 to 152.60.29.190152.60.29.19162
120152.60.29.192/26152.60.29.193 to 152.60.29.254152.60.29.25562
121152.60.30.0/26152.60.30.1 to 152.60.30.62152.60.30.6362
122152.60.30.64/26152.60.30.65 to 152.60.30.126152.60.30.12762
123152.60.30.128/26152.60.30.129 to 152.60.30.190152.60.30.19162
124152.60.30.192/26152.60.30.193 to 152.60.30.254152.60.30.25562
125152.60.31.0/26152.60.31.1 to 152.60.31.62152.60.31.6362
126152.60.31.64/26152.60.31.65 to 152.60.31.126152.60.31.12762
127152.60.31.128/26152.60.31.129 to 152.60.31.190152.60.31.19162
128152.60.31.192/26152.60.31.193 to 152.60.31.254152.60.31.25562
129152.60.32.0/26152.60.32.1 to 152.60.32.62152.60.32.6362
130152.60.32.64/26152.60.32.65 to 152.60.32.126152.60.32.12762
131152.60.32.128/26152.60.32.129 to 152.60.32.190152.60.32.19162
132152.60.32.192/26152.60.32.193 to 152.60.32.254152.60.32.25562
133152.60.33.0/26152.60.33.1 to 152.60.33.62152.60.33.6362
134152.60.33.64/26152.60.33.65 to 152.60.33.126152.60.33.12762
135152.60.33.128/26152.60.33.129 to 152.60.33.190152.60.33.19162
136152.60.33.192/26152.60.33.193 to 152.60.33.254152.60.33.25562
137152.60.34.0/26152.60.34.1 to 152.60.34.62152.60.34.6362
138152.60.34.64/26152.60.34.65 to 152.60.34.126152.60.34.12762
139152.60.34.128/26152.60.34.129 to 152.60.34.190152.60.34.19162
140152.60.34.192/26152.60.34.193 to 152.60.34.254152.60.34.25562
141152.60.35.0/26152.60.35.1 to 152.60.35.62152.60.35.6362
142152.60.35.64/26152.60.35.65 to 152.60.35.126152.60.35.12762
143152.60.35.128/26152.60.35.129 to 152.60.35.190152.60.35.19162
144152.60.35.192/26152.60.35.193 to 152.60.35.254152.60.35.25562
145152.60.36.0/26152.60.36.1 to 152.60.36.62152.60.36.6362
146152.60.36.64/26152.60.36.65 to 152.60.36.126152.60.36.12762
147152.60.36.128/26152.60.36.129 to 152.60.36.190152.60.36.19162
148152.60.36.192/26152.60.36.193 to 152.60.36.254152.60.36.25562
149152.60.37.0/26152.60.37.1 to 152.60.37.62152.60.37.6362
150152.60.37.64/26152.60.37.65 to 152.60.37.126152.60.37.12762
151152.60.37.128/26152.60.37.129 to 152.60.37.190152.60.37.19162
152152.60.37.192/26152.60.37.193 to 152.60.37.254152.60.37.25562
153152.60.38.0/26152.60.38.1 to 152.60.38.62152.60.38.6362
154152.60.38.64/26152.60.38.65 to 152.60.38.126152.60.38.12762
155152.60.38.128/26152.60.38.129 to 152.60.38.190152.60.38.19162
156152.60.38.192/26152.60.38.193 to 152.60.38.254152.60.38.25562
157152.60.39.0/26152.60.39.1 to 152.60.39.62152.60.39.6362
158152.60.39.64/26152.60.39.65 to 152.60.39.126152.60.39.12762
159152.60.39.128/26152.60.39.129 to 152.60.39.190152.60.39.19162
160152.60.39.192/26152.60.39.193 to 152.60.39.254152.60.39.25562
161152.60.40.0/26152.60.40.1 to 152.60.40.62152.60.40.6362
162152.60.40.64/26152.60.40.65 to 152.60.40.126152.60.40.12762
163152.60.40.128/26152.60.40.129 to 152.60.40.190152.60.40.19162
164152.60.40.192/26152.60.40.193 to 152.60.40.254152.60.40.25562
165152.60.41.0/26152.60.41.1 to 152.60.41.62152.60.41.6362
166152.60.41.64/26152.60.41.65 to 152.60.41.126152.60.41.12762
167152.60.41.128/26152.60.41.129 to 152.60.41.190152.60.41.19162
168152.60.41.192/26152.60.41.193 to 152.60.41.254152.60.41.25562
169152.60.42.0/26152.60.42.1 to 152.60.42.62152.60.42.6362
170152.60.42.64/26152.60.42.65 to 152.60.42.126152.60.42.12762
171152.60.42.128/26152.60.42.129 to 152.60.42.190152.60.42.19162
172152.60.42.192/26152.60.42.193 to 152.60.42.254152.60.42.25562
173152.60.43.0/26152.60.43.1 to 152.60.43.62152.60.43.6362
174152.60.43.64/26152.60.43.65 to 152.60.43.126152.60.43.12762
175152.60.43.128/26152.60.43.129 to 152.60.43.190152.60.43.19162
176152.60.43.192/26152.60.43.193 to 152.60.43.254152.60.43.25562
177152.60.44.0/26152.60.44.1 to 152.60.44.62152.60.44.6362
178152.60.44.64/26152.60.44.65 to 152.60.44.126152.60.44.12762
179152.60.44.128/26152.60.44.129 to 152.60.44.190152.60.44.19162
180152.60.44.192/26152.60.44.193 to 152.60.44.254152.60.44.25562
181152.60.45.0/26152.60.45.1 to 152.60.45.62152.60.45.6362
182152.60.45.64/26152.60.45.65 to 152.60.45.126152.60.45.12762
183152.60.45.128/26152.60.45.129 to 152.60.45.190152.60.45.19162
184152.60.45.192/26152.60.45.193 to 152.60.45.254152.60.45.25562
185152.60.46.0/26152.60.46.1 to 152.60.46.62152.60.46.6362
186152.60.46.64/26152.60.46.65 to 152.60.46.126152.60.46.12762
187152.60.46.128/26152.60.46.129 to 152.60.46.190152.60.46.19162
188152.60.46.192/26152.60.46.193 to 152.60.46.254152.60.46.25562
189152.60.47.0/26152.60.47.1 to 152.60.47.62152.60.47.6362
190152.60.47.64/26152.60.47.65 to 152.60.47.126152.60.47.12762
191152.60.47.128/26152.60.47.129 to 152.60.47.190152.60.47.19162
192152.60.47.192/26152.60.47.193 to 152.60.47.254152.60.47.25562
193152.60.48.0/26152.60.48.1 to 152.60.48.62152.60.48.6362
194152.60.48.64/26152.60.48.65 to 152.60.48.126152.60.48.12762
195152.60.48.128/26152.60.48.129 to 152.60.48.190152.60.48.19162
196152.60.48.192/26152.60.48.193 to 152.60.48.254152.60.48.25562
197152.60.49.0/26152.60.49.1 to 152.60.49.62152.60.49.6362
198152.60.49.64/26152.60.49.65 to 152.60.49.126152.60.49.12762
199152.60.49.128/26152.60.49.129 to 152.60.49.190152.60.49.19162
200152.60.49.192/26152.60.49.193 to 152.60.49.254152.60.49.25562
201152.60.50.0/26152.60.50.1 to 152.60.50.62152.60.50.6362
202152.60.50.64/26152.60.50.65 to 152.60.50.126152.60.50.12762
203152.60.50.128/26152.60.50.129 to 152.60.50.190152.60.50.19162
204152.60.50.192/26152.60.50.193 to 152.60.50.254152.60.50.25562
205152.60.51.0/26152.60.51.1 to 152.60.51.62152.60.51.6362
206152.60.51.64/26152.60.51.65 to 152.60.51.126152.60.51.12762
207152.60.51.128/26152.60.51.129 to 152.60.51.190152.60.51.19162
208152.60.51.192/26152.60.51.193 to 152.60.51.254152.60.51.25562
209152.60.52.0/26152.60.52.1 to 152.60.52.62152.60.52.6362
210152.60.52.64/26152.60.52.65 to 152.60.52.126152.60.52.12762
211152.60.52.128/26152.60.52.129 to 152.60.52.190152.60.52.19162
212152.60.52.192/26152.60.52.193 to 152.60.52.254152.60.52.25562
213152.60.53.0/26152.60.53.1 to 152.60.53.62152.60.53.6362
214152.60.53.64/26152.60.53.65 to 152.60.53.126152.60.53.12762
215152.60.53.128/26152.60.53.129 to 152.60.53.190152.60.53.19162
216152.60.53.192/26152.60.53.193 to 152.60.53.254152.60.53.25562
217152.60.54.0/26152.60.54.1 to 152.60.54.62152.60.54.6362
218152.60.54.64/26152.60.54.65 to 152.60.54.126152.60.54.12762
219152.60.54.128/26152.60.54.129 to 152.60.54.190152.60.54.19162
220152.60.54.192/26152.60.54.193 to 152.60.54.254152.60.54.25562
221152.60.55.0/26152.60.55.1 to 152.60.55.62152.60.55.6362
222152.60.55.64/26152.60.55.65 to 152.60.55.126152.60.55.12762
223152.60.55.128/26152.60.55.129 to 152.60.55.190152.60.55.19162
224152.60.55.192/26152.60.55.193 to 152.60.55.254152.60.55.25562
225152.60.56.0/26152.60.56.1 to 152.60.56.62152.60.56.6362
226152.60.56.64/26152.60.56.65 to 152.60.56.126152.60.56.12762
227152.60.56.128/26152.60.56.129 to 152.60.56.190152.60.56.19162
228152.60.56.192/26152.60.56.193 to 152.60.56.254152.60.56.25562
229152.60.57.0/26152.60.57.1 to 152.60.57.62152.60.57.6362
230152.60.57.64/26152.60.57.65 to 152.60.57.126152.60.57.12762
231152.60.57.128/26152.60.57.129 to 152.60.57.190152.60.57.19162
232152.60.57.192/26152.60.57.193 to 152.60.57.254152.60.57.25562
233152.60.58.0/26152.60.58.1 to 152.60.58.62152.60.58.6362
234152.60.58.64/26152.60.58.65 to 152.60.58.126152.60.58.12762
235152.60.58.128/26152.60.58.129 to 152.60.58.190152.60.58.19162
236152.60.58.192/26152.60.58.193 to 152.60.58.254152.60.58.25562
237152.60.59.0/26152.60.59.1 to 152.60.59.62152.60.59.6362
238152.60.59.64/26152.60.59.65 to 152.60.59.126152.60.59.12762
239152.60.59.128/26152.60.59.129 to 152.60.59.190152.60.59.19162
240152.60.59.192/26152.60.59.193 to 152.60.59.254152.60.59.25562
241152.60.60.0/26152.60.60.1 to 152.60.60.62152.60.60.6362
242152.60.60.64/26152.60.60.65 to 152.60.60.126152.60.60.12762
243152.60.60.128/26152.60.60.129 to 152.60.60.190152.60.60.19162
244152.60.60.192/26152.60.60.193 to 152.60.60.254152.60.60.25562
245152.60.61.0/26152.60.61.1 to 152.60.61.62152.60.61.6362
246152.60.61.64/26152.60.61.65 to 152.60.61.126152.60.61.12762
247152.60.61.128/26152.60.61.129 to 152.60.61.190152.60.61.19162
248152.60.61.192/26152.60.61.193 to 152.60.61.254152.60.61.25562
249152.60.62.0/26152.60.62.1 to 152.60.62.62152.60.62.6362
250152.60.62.64/26152.60.62.65 to 152.60.62.126152.60.62.12762
251152.60.62.128/26152.60.62.129 to 152.60.62.190152.60.62.19162
252152.60.62.192/26152.60.62.193 to 152.60.62.254152.60.62.25562
253152.60.63.0/26152.60.63.1 to 152.60.63.62152.60.63.6362
254152.60.63.64/26152.60.63.65 to 152.60.63.126152.60.63.12762
255152.60.63.128/26152.60.63.129 to 152.60.63.190152.60.63.19162
256152.60.63.192/26152.60.63.193 to 152.60.63.254152.60.63.25562

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.