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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.

Network160.0.0.0/8
Usable hosts16,777,214
Subnet mask255.0.0.0
Addresses16,777,216
Network address
160.0.0.0
Broadcast address
160.255.255.255
First usable
160.0.0.1
Last usable
160.255.255.254
Usable hosts
16,777,214 (16,777,216 less the network and broadcast addresses)
Subnet mask
255.0.0.0
Wildcard mask
0.255.255.255 (Cisco ACLs, OSPF)
Prefix length
/8
Type
Public public
Old class
B (default /16)
As numbers
Hex A0000000 · Integer 2684354560 to 2701131775
Reverse DNS zone
160.in-addr.arpa
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address10100000..00000000.00000000.00000000160.0.0.0
Subnet mask11111111..00000000.00000000.00000000255.0.0.0
Network10100000..00000000.00000000.00000000160.0.0.0
Broadcast10100000..11111111.11111111.11111111160.255.255.255
Split into smaller subnets/18
/9 (2)/10 (4)/11 (8)/12 (16)/13 (32)/14 (64)/15 (128)/16 (256)/17 (512)/18 (1,024)/19 (2,048)/20 (4,096)

160.0.0.0/8 makes 1,024 subnets of /18; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
1160.0.0.0/18160.0.0.1 to 160.0.63.254160.0.63.25516,382
2160.0.64.0/18160.0.64.1 to 160.0.127.254160.0.127.25516,382
3160.0.128.0/18160.0.128.1 to 160.0.191.254160.0.191.25516,382
4160.0.192.0/18160.0.192.1 to 160.0.255.254160.0.255.25516,382
5160.1.0.0/18160.1.0.1 to 160.1.63.254160.1.63.25516,382
6160.1.64.0/18160.1.64.1 to 160.1.127.254160.1.127.25516,382
7160.1.128.0/18160.1.128.1 to 160.1.191.254160.1.191.25516,382
8160.1.192.0/18160.1.192.1 to 160.1.255.254160.1.255.25516,382
9160.2.0.0/18160.2.0.1 to 160.2.63.254160.2.63.25516,382
10160.2.64.0/18160.2.64.1 to 160.2.127.254160.2.127.25516,382
11160.2.128.0/18160.2.128.1 to 160.2.191.254160.2.191.25516,382
12160.2.192.0/18160.2.192.1 to 160.2.255.254160.2.255.25516,382
13160.3.0.0/18160.3.0.1 to 160.3.63.254160.3.63.25516,382
14160.3.64.0/18160.3.64.1 to 160.3.127.254160.3.127.25516,382
15160.3.128.0/18160.3.128.1 to 160.3.191.254160.3.191.25516,382
16160.3.192.0/18160.3.192.1 to 160.3.255.254160.3.255.25516,382
17160.4.0.0/18160.4.0.1 to 160.4.63.254160.4.63.25516,382
18160.4.64.0/18160.4.64.1 to 160.4.127.254160.4.127.25516,382
19160.4.128.0/18160.4.128.1 to 160.4.191.254160.4.191.25516,382
20160.4.192.0/18160.4.192.1 to 160.4.255.254160.4.255.25516,382
21160.5.0.0/18160.5.0.1 to 160.5.63.254160.5.63.25516,382
22160.5.64.0/18160.5.64.1 to 160.5.127.254160.5.127.25516,382
23160.5.128.0/18160.5.128.1 to 160.5.191.254160.5.191.25516,382
24160.5.192.0/18160.5.192.1 to 160.5.255.254160.5.255.25516,382
25160.6.0.0/18160.6.0.1 to 160.6.63.254160.6.63.25516,382
26160.6.64.0/18160.6.64.1 to 160.6.127.254160.6.127.25516,382
27160.6.128.0/18160.6.128.1 to 160.6.191.254160.6.191.25516,382
28160.6.192.0/18160.6.192.1 to 160.6.255.254160.6.255.25516,382
29160.7.0.0/18160.7.0.1 to 160.7.63.254160.7.63.25516,382
30160.7.64.0/18160.7.64.1 to 160.7.127.254160.7.127.25516,382
31160.7.128.0/18160.7.128.1 to 160.7.191.254160.7.191.25516,382
32160.7.192.0/18160.7.192.1 to 160.7.255.254160.7.255.25516,382
33160.8.0.0/18160.8.0.1 to 160.8.63.254160.8.63.25516,382
34160.8.64.0/18160.8.64.1 to 160.8.127.254160.8.127.25516,382
35160.8.128.0/18160.8.128.1 to 160.8.191.254160.8.191.25516,382
36160.8.192.0/18160.8.192.1 to 160.8.255.254160.8.255.25516,382
37160.9.0.0/18160.9.0.1 to 160.9.63.254160.9.63.25516,382
38160.9.64.0/18160.9.64.1 to 160.9.127.254160.9.127.25516,382
39160.9.128.0/18160.9.128.1 to 160.9.191.254160.9.191.25516,382
40160.9.192.0/18160.9.192.1 to 160.9.255.254160.9.255.25516,382
41160.10.0.0/18160.10.0.1 to 160.10.63.254160.10.63.25516,382
42160.10.64.0/18160.10.64.1 to 160.10.127.254160.10.127.25516,382
43160.10.128.0/18160.10.128.1 to 160.10.191.254160.10.191.25516,382
44160.10.192.0/18160.10.192.1 to 160.10.255.254160.10.255.25516,382
45160.11.0.0/18160.11.0.1 to 160.11.63.254160.11.63.25516,382
46160.11.64.0/18160.11.64.1 to 160.11.127.254160.11.127.25516,382
47160.11.128.0/18160.11.128.1 to 160.11.191.254160.11.191.25516,382
48160.11.192.0/18160.11.192.1 to 160.11.255.254160.11.255.25516,382
49160.12.0.0/18160.12.0.1 to 160.12.63.254160.12.63.25516,382
50160.12.64.0/18160.12.64.1 to 160.12.127.254160.12.127.25516,382
51160.12.128.0/18160.12.128.1 to 160.12.191.254160.12.191.25516,382
52160.12.192.0/18160.12.192.1 to 160.12.255.254160.12.255.25516,382
53160.13.0.0/18160.13.0.1 to 160.13.63.254160.13.63.25516,382
54160.13.64.0/18160.13.64.1 to 160.13.127.254160.13.127.25516,382
55160.13.128.0/18160.13.128.1 to 160.13.191.254160.13.191.25516,382
56160.13.192.0/18160.13.192.1 to 160.13.255.254160.13.255.25516,382
57160.14.0.0/18160.14.0.1 to 160.14.63.254160.14.63.25516,382
58160.14.64.0/18160.14.64.1 to 160.14.127.254160.14.127.25516,382
59160.14.128.0/18160.14.128.1 to 160.14.191.254160.14.191.25516,382
60160.14.192.0/18160.14.192.1 to 160.14.255.254160.14.255.25516,382
61160.15.0.0/18160.15.0.1 to 160.15.63.254160.15.63.25516,382
62160.15.64.0/18160.15.64.1 to 160.15.127.254160.15.127.25516,382
63160.15.128.0/18160.15.128.1 to 160.15.191.254160.15.191.25516,382
64160.15.192.0/18160.15.192.1 to 160.15.255.254160.15.255.25516,382
65160.16.0.0/18160.16.0.1 to 160.16.63.254160.16.63.25516,382
66160.16.64.0/18160.16.64.1 to 160.16.127.254160.16.127.25516,382
67160.16.128.0/18160.16.128.1 to 160.16.191.254160.16.191.25516,382
68160.16.192.0/18160.16.192.1 to 160.16.255.254160.16.255.25516,382
69160.17.0.0/18160.17.0.1 to 160.17.63.254160.17.63.25516,382
70160.17.64.0/18160.17.64.1 to 160.17.127.254160.17.127.25516,382
71160.17.128.0/18160.17.128.1 to 160.17.191.254160.17.191.25516,382
72160.17.192.0/18160.17.192.1 to 160.17.255.254160.17.255.25516,382
73160.18.0.0/18160.18.0.1 to 160.18.63.254160.18.63.25516,382
74160.18.64.0/18160.18.64.1 to 160.18.127.254160.18.127.25516,382
75160.18.128.0/18160.18.128.1 to 160.18.191.254160.18.191.25516,382
76160.18.192.0/18160.18.192.1 to 160.18.255.254160.18.255.25516,382
77160.19.0.0/18160.19.0.1 to 160.19.63.254160.19.63.25516,382
78160.19.64.0/18160.19.64.1 to 160.19.127.254160.19.127.25516,382
79160.19.128.0/18160.19.128.1 to 160.19.191.254160.19.191.25516,382
80160.19.192.0/18160.19.192.1 to 160.19.255.254160.19.255.25516,382
81160.20.0.0/18160.20.0.1 to 160.20.63.254160.20.63.25516,382
82160.20.64.0/18160.20.64.1 to 160.20.127.254160.20.127.25516,382
83160.20.128.0/18160.20.128.1 to 160.20.191.254160.20.191.25516,382
84160.20.192.0/18160.20.192.1 to 160.20.255.254160.20.255.25516,382
85160.21.0.0/18160.21.0.1 to 160.21.63.254160.21.63.25516,382
86160.21.64.0/18160.21.64.1 to 160.21.127.254160.21.127.25516,382
87160.21.128.0/18160.21.128.1 to 160.21.191.254160.21.191.25516,382
88160.21.192.0/18160.21.192.1 to 160.21.255.254160.21.255.25516,382
89160.22.0.0/18160.22.0.1 to 160.22.63.254160.22.63.25516,382
90160.22.64.0/18160.22.64.1 to 160.22.127.254160.22.127.25516,382
91160.22.128.0/18160.22.128.1 to 160.22.191.254160.22.191.25516,382
92160.22.192.0/18160.22.192.1 to 160.22.255.254160.22.255.25516,382
93160.23.0.0/18160.23.0.1 to 160.23.63.254160.23.63.25516,382
94160.23.64.0/18160.23.64.1 to 160.23.127.254160.23.127.25516,382
95160.23.128.0/18160.23.128.1 to 160.23.191.254160.23.191.25516,382
96160.23.192.0/18160.23.192.1 to 160.23.255.254160.23.255.25516,382
97160.24.0.0/18160.24.0.1 to 160.24.63.254160.24.63.25516,382
98160.24.64.0/18160.24.64.1 to 160.24.127.254160.24.127.25516,382
99160.24.128.0/18160.24.128.1 to 160.24.191.254160.24.191.25516,382
100160.24.192.0/18160.24.192.1 to 160.24.255.254160.24.255.25516,382
101160.25.0.0/18160.25.0.1 to 160.25.63.254160.25.63.25516,382
102160.25.64.0/18160.25.64.1 to 160.25.127.254160.25.127.25516,382
103160.25.128.0/18160.25.128.1 to 160.25.191.254160.25.191.25516,382
104160.25.192.0/18160.25.192.1 to 160.25.255.254160.25.255.25516,382
105160.26.0.0/18160.26.0.1 to 160.26.63.254160.26.63.25516,382
106160.26.64.0/18160.26.64.1 to 160.26.127.254160.26.127.25516,382
107160.26.128.0/18160.26.128.1 to 160.26.191.254160.26.191.25516,382
108160.26.192.0/18160.26.192.1 to 160.26.255.254160.26.255.25516,382
109160.27.0.0/18160.27.0.1 to 160.27.63.254160.27.63.25516,382
110160.27.64.0/18160.27.64.1 to 160.27.127.254160.27.127.25516,382
111160.27.128.0/18160.27.128.1 to 160.27.191.254160.27.191.25516,382
112160.27.192.0/18160.27.192.1 to 160.27.255.254160.27.255.25516,382
113160.28.0.0/18160.28.0.1 to 160.28.63.254160.28.63.25516,382
114160.28.64.0/18160.28.64.1 to 160.28.127.254160.28.127.25516,382
115160.28.128.0/18160.28.128.1 to 160.28.191.254160.28.191.25516,382
116160.28.192.0/18160.28.192.1 to 160.28.255.254160.28.255.25516,382
117160.29.0.0/18160.29.0.1 to 160.29.63.254160.29.63.25516,382
118160.29.64.0/18160.29.64.1 to 160.29.127.254160.29.127.25516,382
119160.29.128.0/18160.29.128.1 to 160.29.191.254160.29.191.25516,382
120160.29.192.0/18160.29.192.1 to 160.29.255.254160.29.255.25516,382
121160.30.0.0/18160.30.0.1 to 160.30.63.254160.30.63.25516,382
122160.30.64.0/18160.30.64.1 to 160.30.127.254160.30.127.25516,382
123160.30.128.0/18160.30.128.1 to 160.30.191.254160.30.191.25516,382
124160.30.192.0/18160.30.192.1 to 160.30.255.254160.30.255.25516,382
125160.31.0.0/18160.31.0.1 to 160.31.63.254160.31.63.25516,382
126160.31.64.0/18160.31.64.1 to 160.31.127.254160.31.127.25516,382
127160.31.128.0/18160.31.128.1 to 160.31.191.254160.31.191.25516,382
128160.31.192.0/18160.31.192.1 to 160.31.255.254160.31.255.25516,382
129160.32.0.0/18160.32.0.1 to 160.32.63.254160.32.63.25516,382
130160.32.64.0/18160.32.64.1 to 160.32.127.254160.32.127.25516,382
131160.32.128.0/18160.32.128.1 to 160.32.191.254160.32.191.25516,382
132160.32.192.0/18160.32.192.1 to 160.32.255.254160.32.255.25516,382
133160.33.0.0/18160.33.0.1 to 160.33.63.254160.33.63.25516,382
134160.33.64.0/18160.33.64.1 to 160.33.127.254160.33.127.25516,382
135160.33.128.0/18160.33.128.1 to 160.33.191.254160.33.191.25516,382
136160.33.192.0/18160.33.192.1 to 160.33.255.254160.33.255.25516,382
137160.34.0.0/18160.34.0.1 to 160.34.63.254160.34.63.25516,382
138160.34.64.0/18160.34.64.1 to 160.34.127.254160.34.127.25516,382
139160.34.128.0/18160.34.128.1 to 160.34.191.254160.34.191.25516,382
140160.34.192.0/18160.34.192.1 to 160.34.255.254160.34.255.25516,382
141160.35.0.0/18160.35.0.1 to 160.35.63.254160.35.63.25516,382
142160.35.64.0/18160.35.64.1 to 160.35.127.254160.35.127.25516,382
143160.35.128.0/18160.35.128.1 to 160.35.191.254160.35.191.25516,382
144160.35.192.0/18160.35.192.1 to 160.35.255.254160.35.255.25516,382
145160.36.0.0/18160.36.0.1 to 160.36.63.254160.36.63.25516,382
146160.36.64.0/18160.36.64.1 to 160.36.127.254160.36.127.25516,382
147160.36.128.0/18160.36.128.1 to 160.36.191.254160.36.191.25516,382
148160.36.192.0/18160.36.192.1 to 160.36.255.254160.36.255.25516,382
149160.37.0.0/18160.37.0.1 to 160.37.63.254160.37.63.25516,382
150160.37.64.0/18160.37.64.1 to 160.37.127.254160.37.127.25516,382
151160.37.128.0/18160.37.128.1 to 160.37.191.254160.37.191.25516,382
152160.37.192.0/18160.37.192.1 to 160.37.255.254160.37.255.25516,382
153160.38.0.0/18160.38.0.1 to 160.38.63.254160.38.63.25516,382
154160.38.64.0/18160.38.64.1 to 160.38.127.254160.38.127.25516,382
155160.38.128.0/18160.38.128.1 to 160.38.191.254160.38.191.25516,382
156160.38.192.0/18160.38.192.1 to 160.38.255.254160.38.255.25516,382
157160.39.0.0/18160.39.0.1 to 160.39.63.254160.39.63.25516,382
158160.39.64.0/18160.39.64.1 to 160.39.127.254160.39.127.25516,382
159160.39.128.0/18160.39.128.1 to 160.39.191.254160.39.191.25516,382
160160.39.192.0/18160.39.192.1 to 160.39.255.254160.39.255.25516,382
161160.40.0.0/18160.40.0.1 to 160.40.63.254160.40.63.25516,382
162160.40.64.0/18160.40.64.1 to 160.40.127.254160.40.127.25516,382
163160.40.128.0/18160.40.128.1 to 160.40.191.254160.40.191.25516,382
164160.40.192.0/18160.40.192.1 to 160.40.255.254160.40.255.25516,382
165160.41.0.0/18160.41.0.1 to 160.41.63.254160.41.63.25516,382
166160.41.64.0/18160.41.64.1 to 160.41.127.254160.41.127.25516,382
167160.41.128.0/18160.41.128.1 to 160.41.191.254160.41.191.25516,382
168160.41.192.0/18160.41.192.1 to 160.41.255.254160.41.255.25516,382
169160.42.0.0/18160.42.0.1 to 160.42.63.254160.42.63.25516,382
170160.42.64.0/18160.42.64.1 to 160.42.127.254160.42.127.25516,382
171160.42.128.0/18160.42.128.1 to 160.42.191.254160.42.191.25516,382
172160.42.192.0/18160.42.192.1 to 160.42.255.254160.42.255.25516,382
173160.43.0.0/18160.43.0.1 to 160.43.63.254160.43.63.25516,382
174160.43.64.0/18160.43.64.1 to 160.43.127.254160.43.127.25516,382
175160.43.128.0/18160.43.128.1 to 160.43.191.254160.43.191.25516,382
176160.43.192.0/18160.43.192.1 to 160.43.255.254160.43.255.25516,382
177160.44.0.0/18160.44.0.1 to 160.44.63.254160.44.63.25516,382
178160.44.64.0/18160.44.64.1 to 160.44.127.254160.44.127.25516,382
179160.44.128.0/18160.44.128.1 to 160.44.191.254160.44.191.25516,382
180160.44.192.0/18160.44.192.1 to 160.44.255.254160.44.255.25516,382
181160.45.0.0/18160.45.0.1 to 160.45.63.254160.45.63.25516,382
182160.45.64.0/18160.45.64.1 to 160.45.127.254160.45.127.25516,382
183160.45.128.0/18160.45.128.1 to 160.45.191.254160.45.191.25516,382
184160.45.192.0/18160.45.192.1 to 160.45.255.254160.45.255.25516,382
185160.46.0.0/18160.46.0.1 to 160.46.63.254160.46.63.25516,382
186160.46.64.0/18160.46.64.1 to 160.46.127.254160.46.127.25516,382
187160.46.128.0/18160.46.128.1 to 160.46.191.254160.46.191.25516,382
188160.46.192.0/18160.46.192.1 to 160.46.255.254160.46.255.25516,382
189160.47.0.0/18160.47.0.1 to 160.47.63.254160.47.63.25516,382
190160.47.64.0/18160.47.64.1 to 160.47.127.254160.47.127.25516,382
191160.47.128.0/18160.47.128.1 to 160.47.191.254160.47.191.25516,382
192160.47.192.0/18160.47.192.1 to 160.47.255.254160.47.255.25516,382
193160.48.0.0/18160.48.0.1 to 160.48.63.254160.48.63.25516,382
194160.48.64.0/18160.48.64.1 to 160.48.127.254160.48.127.25516,382
195160.48.128.0/18160.48.128.1 to 160.48.191.254160.48.191.25516,382
196160.48.192.0/18160.48.192.1 to 160.48.255.254160.48.255.25516,382
197160.49.0.0/18160.49.0.1 to 160.49.63.254160.49.63.25516,382
198160.49.64.0/18160.49.64.1 to 160.49.127.254160.49.127.25516,382
199160.49.128.0/18160.49.128.1 to 160.49.191.254160.49.191.25516,382
200160.49.192.0/18160.49.192.1 to 160.49.255.254160.49.255.25516,382
201160.50.0.0/18160.50.0.1 to 160.50.63.254160.50.63.25516,382
202160.50.64.0/18160.50.64.1 to 160.50.127.254160.50.127.25516,382
203160.50.128.0/18160.50.128.1 to 160.50.191.254160.50.191.25516,382
204160.50.192.0/18160.50.192.1 to 160.50.255.254160.50.255.25516,382
205160.51.0.0/18160.51.0.1 to 160.51.63.254160.51.63.25516,382
206160.51.64.0/18160.51.64.1 to 160.51.127.254160.51.127.25516,382
207160.51.128.0/18160.51.128.1 to 160.51.191.254160.51.191.25516,382
208160.51.192.0/18160.51.192.1 to 160.51.255.254160.51.255.25516,382
209160.52.0.0/18160.52.0.1 to 160.52.63.254160.52.63.25516,382
210160.52.64.0/18160.52.64.1 to 160.52.127.254160.52.127.25516,382
211160.52.128.0/18160.52.128.1 to 160.52.191.254160.52.191.25516,382
212160.52.192.0/18160.52.192.1 to 160.52.255.254160.52.255.25516,382
213160.53.0.0/18160.53.0.1 to 160.53.63.254160.53.63.25516,382
214160.53.64.0/18160.53.64.1 to 160.53.127.254160.53.127.25516,382
215160.53.128.0/18160.53.128.1 to 160.53.191.254160.53.191.25516,382
216160.53.192.0/18160.53.192.1 to 160.53.255.254160.53.255.25516,382
217160.54.0.0/18160.54.0.1 to 160.54.63.254160.54.63.25516,382
218160.54.64.0/18160.54.64.1 to 160.54.127.254160.54.127.25516,382
219160.54.128.0/18160.54.128.1 to 160.54.191.254160.54.191.25516,382
220160.54.192.0/18160.54.192.1 to 160.54.255.254160.54.255.25516,382
221160.55.0.0/18160.55.0.1 to 160.55.63.254160.55.63.25516,382
222160.55.64.0/18160.55.64.1 to 160.55.127.254160.55.127.25516,382
223160.55.128.0/18160.55.128.1 to 160.55.191.254160.55.191.25516,382
224160.55.192.0/18160.55.192.1 to 160.55.255.254160.55.255.25516,382
225160.56.0.0/18160.56.0.1 to 160.56.63.254160.56.63.25516,382
226160.56.64.0/18160.56.64.1 to 160.56.127.254160.56.127.25516,382
227160.56.128.0/18160.56.128.1 to 160.56.191.254160.56.191.25516,382
228160.56.192.0/18160.56.192.1 to 160.56.255.254160.56.255.25516,382
229160.57.0.0/18160.57.0.1 to 160.57.63.254160.57.63.25516,382
230160.57.64.0/18160.57.64.1 to 160.57.127.254160.57.127.25516,382
231160.57.128.0/18160.57.128.1 to 160.57.191.254160.57.191.25516,382
232160.57.192.0/18160.57.192.1 to 160.57.255.254160.57.255.25516,382
233160.58.0.0/18160.58.0.1 to 160.58.63.254160.58.63.25516,382
234160.58.64.0/18160.58.64.1 to 160.58.127.254160.58.127.25516,382
235160.58.128.0/18160.58.128.1 to 160.58.191.254160.58.191.25516,382
236160.58.192.0/18160.58.192.1 to 160.58.255.254160.58.255.25516,382
237160.59.0.0/18160.59.0.1 to 160.59.63.254160.59.63.25516,382
238160.59.64.0/18160.59.64.1 to 160.59.127.254160.59.127.25516,382
239160.59.128.0/18160.59.128.1 to 160.59.191.254160.59.191.25516,382
240160.59.192.0/18160.59.192.1 to 160.59.255.254160.59.255.25516,382
241160.60.0.0/18160.60.0.1 to 160.60.63.254160.60.63.25516,382
242160.60.64.0/18160.60.64.1 to 160.60.127.254160.60.127.25516,382
243160.60.128.0/18160.60.128.1 to 160.60.191.254160.60.191.25516,382
244160.60.192.0/18160.60.192.1 to 160.60.255.254160.60.255.25516,382
245160.61.0.0/18160.61.0.1 to 160.61.63.254160.61.63.25516,382
246160.61.64.0/18160.61.64.1 to 160.61.127.254160.61.127.25516,382
247160.61.128.0/18160.61.128.1 to 160.61.191.254160.61.191.25516,382
248160.61.192.0/18160.61.192.1 to 160.61.255.254160.61.255.25516,382
249160.62.0.0/18160.62.0.1 to 160.62.63.254160.62.63.25516,382
250160.62.64.0/18160.62.64.1 to 160.62.127.254160.62.127.25516,382
251160.62.128.0/18160.62.128.1 to 160.62.191.254160.62.191.25516,382
252160.62.192.0/18160.62.192.1 to 160.62.255.254160.62.255.25516,382
253160.63.0.0/18160.63.0.1 to 160.63.63.254160.63.63.25516,382
254160.63.64.0/18160.63.64.1 to 160.63.127.254160.63.127.25516,382
255160.63.128.0/18160.63.128.1 to 160.63.191.254160.63.191.25516,382
256160.63.192.0/18160.63.192.1 to 160.63.255.254160.63.255.25516,382

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.