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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.

Network230.167.0.0/16
Usable hosts65,534
Subnet mask255.255.0.0
Addresses65,536
Network address
230.167.0.0
Broadcast address
230.167.255.255
First usable
230.167.0.1
Last usable
230.167.255.254
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
Multicast 224.0.0.0/4
One-to-many traffic, such as IPTV and routing protocols
Old class
D (multicast)
As numbers
Hex E6A70000 · Integer 3869704192 to 3869769727
Reverse DNS zone
167.230.in-addr.arpa
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address11100110.10100111..00000000.00000000230.167.0.0
Subnet mask11111111.11111111..00000000.00000000255.255.0.0
Network11100110.10100111..00000000.00000000230.167.0.0
Broadcast11100110.10100111..11111111.11111111230.167.255.255
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)

230.167.0.0/16 makes 1,024 subnets of /26; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
1230.167.0.0/26230.167.0.1 to 230.167.0.62230.167.0.6362
2230.167.0.64/26230.167.0.65 to 230.167.0.126230.167.0.12762
3230.167.0.128/26230.167.0.129 to 230.167.0.190230.167.0.19162
4230.167.0.192/26230.167.0.193 to 230.167.0.254230.167.0.25562
5230.167.1.0/26230.167.1.1 to 230.167.1.62230.167.1.6362
6230.167.1.64/26230.167.1.65 to 230.167.1.126230.167.1.12762
7230.167.1.128/26230.167.1.129 to 230.167.1.190230.167.1.19162
8230.167.1.192/26230.167.1.193 to 230.167.1.254230.167.1.25562
9230.167.2.0/26230.167.2.1 to 230.167.2.62230.167.2.6362
10230.167.2.64/26230.167.2.65 to 230.167.2.126230.167.2.12762
11230.167.2.128/26230.167.2.129 to 230.167.2.190230.167.2.19162
12230.167.2.192/26230.167.2.193 to 230.167.2.254230.167.2.25562
13230.167.3.0/26230.167.3.1 to 230.167.3.62230.167.3.6362
14230.167.3.64/26230.167.3.65 to 230.167.3.126230.167.3.12762
15230.167.3.128/26230.167.3.129 to 230.167.3.190230.167.3.19162
16230.167.3.192/26230.167.3.193 to 230.167.3.254230.167.3.25562
17230.167.4.0/26230.167.4.1 to 230.167.4.62230.167.4.6362
18230.167.4.64/26230.167.4.65 to 230.167.4.126230.167.4.12762
19230.167.4.128/26230.167.4.129 to 230.167.4.190230.167.4.19162
20230.167.4.192/26230.167.4.193 to 230.167.4.254230.167.4.25562
21230.167.5.0/26230.167.5.1 to 230.167.5.62230.167.5.6362
22230.167.5.64/26230.167.5.65 to 230.167.5.126230.167.5.12762
23230.167.5.128/26230.167.5.129 to 230.167.5.190230.167.5.19162
24230.167.5.192/26230.167.5.193 to 230.167.5.254230.167.5.25562
25230.167.6.0/26230.167.6.1 to 230.167.6.62230.167.6.6362
26230.167.6.64/26230.167.6.65 to 230.167.6.126230.167.6.12762
27230.167.6.128/26230.167.6.129 to 230.167.6.190230.167.6.19162
28230.167.6.192/26230.167.6.193 to 230.167.6.254230.167.6.25562
29230.167.7.0/26230.167.7.1 to 230.167.7.62230.167.7.6362
30230.167.7.64/26230.167.7.65 to 230.167.7.126230.167.7.12762
31230.167.7.128/26230.167.7.129 to 230.167.7.190230.167.7.19162
32230.167.7.192/26230.167.7.193 to 230.167.7.254230.167.7.25562
33230.167.8.0/26230.167.8.1 to 230.167.8.62230.167.8.6362
34230.167.8.64/26230.167.8.65 to 230.167.8.126230.167.8.12762
35230.167.8.128/26230.167.8.129 to 230.167.8.190230.167.8.19162
36230.167.8.192/26230.167.8.193 to 230.167.8.254230.167.8.25562
37230.167.9.0/26230.167.9.1 to 230.167.9.62230.167.9.6362
38230.167.9.64/26230.167.9.65 to 230.167.9.126230.167.9.12762
39230.167.9.128/26230.167.9.129 to 230.167.9.190230.167.9.19162
40230.167.9.192/26230.167.9.193 to 230.167.9.254230.167.9.25562
41230.167.10.0/26230.167.10.1 to 230.167.10.62230.167.10.6362
42230.167.10.64/26230.167.10.65 to 230.167.10.126230.167.10.12762
43230.167.10.128/26230.167.10.129 to 230.167.10.190230.167.10.19162
44230.167.10.192/26230.167.10.193 to 230.167.10.254230.167.10.25562
45230.167.11.0/26230.167.11.1 to 230.167.11.62230.167.11.6362
46230.167.11.64/26230.167.11.65 to 230.167.11.126230.167.11.12762
47230.167.11.128/26230.167.11.129 to 230.167.11.190230.167.11.19162
48230.167.11.192/26230.167.11.193 to 230.167.11.254230.167.11.25562
49230.167.12.0/26230.167.12.1 to 230.167.12.62230.167.12.6362
50230.167.12.64/26230.167.12.65 to 230.167.12.126230.167.12.12762
51230.167.12.128/26230.167.12.129 to 230.167.12.190230.167.12.19162
52230.167.12.192/26230.167.12.193 to 230.167.12.254230.167.12.25562
53230.167.13.0/26230.167.13.1 to 230.167.13.62230.167.13.6362
54230.167.13.64/26230.167.13.65 to 230.167.13.126230.167.13.12762
55230.167.13.128/26230.167.13.129 to 230.167.13.190230.167.13.19162
56230.167.13.192/26230.167.13.193 to 230.167.13.254230.167.13.25562
57230.167.14.0/26230.167.14.1 to 230.167.14.62230.167.14.6362
58230.167.14.64/26230.167.14.65 to 230.167.14.126230.167.14.12762
59230.167.14.128/26230.167.14.129 to 230.167.14.190230.167.14.19162
60230.167.14.192/26230.167.14.193 to 230.167.14.254230.167.14.25562
61230.167.15.0/26230.167.15.1 to 230.167.15.62230.167.15.6362
62230.167.15.64/26230.167.15.65 to 230.167.15.126230.167.15.12762
63230.167.15.128/26230.167.15.129 to 230.167.15.190230.167.15.19162
64230.167.15.192/26230.167.15.193 to 230.167.15.254230.167.15.25562
65230.167.16.0/26230.167.16.1 to 230.167.16.62230.167.16.6362
66230.167.16.64/26230.167.16.65 to 230.167.16.126230.167.16.12762
67230.167.16.128/26230.167.16.129 to 230.167.16.190230.167.16.19162
68230.167.16.192/26230.167.16.193 to 230.167.16.254230.167.16.25562
69230.167.17.0/26230.167.17.1 to 230.167.17.62230.167.17.6362
70230.167.17.64/26230.167.17.65 to 230.167.17.126230.167.17.12762
71230.167.17.128/26230.167.17.129 to 230.167.17.190230.167.17.19162
72230.167.17.192/26230.167.17.193 to 230.167.17.254230.167.17.25562
73230.167.18.0/26230.167.18.1 to 230.167.18.62230.167.18.6362
74230.167.18.64/26230.167.18.65 to 230.167.18.126230.167.18.12762
75230.167.18.128/26230.167.18.129 to 230.167.18.190230.167.18.19162
76230.167.18.192/26230.167.18.193 to 230.167.18.254230.167.18.25562
77230.167.19.0/26230.167.19.1 to 230.167.19.62230.167.19.6362
78230.167.19.64/26230.167.19.65 to 230.167.19.126230.167.19.12762
79230.167.19.128/26230.167.19.129 to 230.167.19.190230.167.19.19162
80230.167.19.192/26230.167.19.193 to 230.167.19.254230.167.19.25562
81230.167.20.0/26230.167.20.1 to 230.167.20.62230.167.20.6362
82230.167.20.64/26230.167.20.65 to 230.167.20.126230.167.20.12762
83230.167.20.128/26230.167.20.129 to 230.167.20.190230.167.20.19162
84230.167.20.192/26230.167.20.193 to 230.167.20.254230.167.20.25562
85230.167.21.0/26230.167.21.1 to 230.167.21.62230.167.21.6362
86230.167.21.64/26230.167.21.65 to 230.167.21.126230.167.21.12762
87230.167.21.128/26230.167.21.129 to 230.167.21.190230.167.21.19162
88230.167.21.192/26230.167.21.193 to 230.167.21.254230.167.21.25562
89230.167.22.0/26230.167.22.1 to 230.167.22.62230.167.22.6362
90230.167.22.64/26230.167.22.65 to 230.167.22.126230.167.22.12762
91230.167.22.128/26230.167.22.129 to 230.167.22.190230.167.22.19162
92230.167.22.192/26230.167.22.193 to 230.167.22.254230.167.22.25562
93230.167.23.0/26230.167.23.1 to 230.167.23.62230.167.23.6362
94230.167.23.64/26230.167.23.65 to 230.167.23.126230.167.23.12762
95230.167.23.128/26230.167.23.129 to 230.167.23.190230.167.23.19162
96230.167.23.192/26230.167.23.193 to 230.167.23.254230.167.23.25562
97230.167.24.0/26230.167.24.1 to 230.167.24.62230.167.24.6362
98230.167.24.64/26230.167.24.65 to 230.167.24.126230.167.24.12762
99230.167.24.128/26230.167.24.129 to 230.167.24.190230.167.24.19162
100230.167.24.192/26230.167.24.193 to 230.167.24.254230.167.24.25562
101230.167.25.0/26230.167.25.1 to 230.167.25.62230.167.25.6362
102230.167.25.64/26230.167.25.65 to 230.167.25.126230.167.25.12762
103230.167.25.128/26230.167.25.129 to 230.167.25.190230.167.25.19162
104230.167.25.192/26230.167.25.193 to 230.167.25.254230.167.25.25562
105230.167.26.0/26230.167.26.1 to 230.167.26.62230.167.26.6362
106230.167.26.64/26230.167.26.65 to 230.167.26.126230.167.26.12762
107230.167.26.128/26230.167.26.129 to 230.167.26.190230.167.26.19162
108230.167.26.192/26230.167.26.193 to 230.167.26.254230.167.26.25562
109230.167.27.0/26230.167.27.1 to 230.167.27.62230.167.27.6362
110230.167.27.64/26230.167.27.65 to 230.167.27.126230.167.27.12762
111230.167.27.128/26230.167.27.129 to 230.167.27.190230.167.27.19162
112230.167.27.192/26230.167.27.193 to 230.167.27.254230.167.27.25562
113230.167.28.0/26230.167.28.1 to 230.167.28.62230.167.28.6362
114230.167.28.64/26230.167.28.65 to 230.167.28.126230.167.28.12762
115230.167.28.128/26230.167.28.129 to 230.167.28.190230.167.28.19162
116230.167.28.192/26230.167.28.193 to 230.167.28.254230.167.28.25562
117230.167.29.0/26230.167.29.1 to 230.167.29.62230.167.29.6362
118230.167.29.64/26230.167.29.65 to 230.167.29.126230.167.29.12762
119230.167.29.128/26230.167.29.129 to 230.167.29.190230.167.29.19162
120230.167.29.192/26230.167.29.193 to 230.167.29.254230.167.29.25562
121230.167.30.0/26230.167.30.1 to 230.167.30.62230.167.30.6362
122230.167.30.64/26230.167.30.65 to 230.167.30.126230.167.30.12762
123230.167.30.128/26230.167.30.129 to 230.167.30.190230.167.30.19162
124230.167.30.192/26230.167.30.193 to 230.167.30.254230.167.30.25562
125230.167.31.0/26230.167.31.1 to 230.167.31.62230.167.31.6362
126230.167.31.64/26230.167.31.65 to 230.167.31.126230.167.31.12762
127230.167.31.128/26230.167.31.129 to 230.167.31.190230.167.31.19162
128230.167.31.192/26230.167.31.193 to 230.167.31.254230.167.31.25562
129230.167.32.0/26230.167.32.1 to 230.167.32.62230.167.32.6362
130230.167.32.64/26230.167.32.65 to 230.167.32.126230.167.32.12762
131230.167.32.128/26230.167.32.129 to 230.167.32.190230.167.32.19162
132230.167.32.192/26230.167.32.193 to 230.167.32.254230.167.32.25562
133230.167.33.0/26230.167.33.1 to 230.167.33.62230.167.33.6362
134230.167.33.64/26230.167.33.65 to 230.167.33.126230.167.33.12762
135230.167.33.128/26230.167.33.129 to 230.167.33.190230.167.33.19162
136230.167.33.192/26230.167.33.193 to 230.167.33.254230.167.33.25562
137230.167.34.0/26230.167.34.1 to 230.167.34.62230.167.34.6362
138230.167.34.64/26230.167.34.65 to 230.167.34.126230.167.34.12762
139230.167.34.128/26230.167.34.129 to 230.167.34.190230.167.34.19162
140230.167.34.192/26230.167.34.193 to 230.167.34.254230.167.34.25562
141230.167.35.0/26230.167.35.1 to 230.167.35.62230.167.35.6362
142230.167.35.64/26230.167.35.65 to 230.167.35.126230.167.35.12762
143230.167.35.128/26230.167.35.129 to 230.167.35.190230.167.35.19162
144230.167.35.192/26230.167.35.193 to 230.167.35.254230.167.35.25562
145230.167.36.0/26230.167.36.1 to 230.167.36.62230.167.36.6362
146230.167.36.64/26230.167.36.65 to 230.167.36.126230.167.36.12762
147230.167.36.128/26230.167.36.129 to 230.167.36.190230.167.36.19162
148230.167.36.192/26230.167.36.193 to 230.167.36.254230.167.36.25562
149230.167.37.0/26230.167.37.1 to 230.167.37.62230.167.37.6362
150230.167.37.64/26230.167.37.65 to 230.167.37.126230.167.37.12762
151230.167.37.128/26230.167.37.129 to 230.167.37.190230.167.37.19162
152230.167.37.192/26230.167.37.193 to 230.167.37.254230.167.37.25562
153230.167.38.0/26230.167.38.1 to 230.167.38.62230.167.38.6362
154230.167.38.64/26230.167.38.65 to 230.167.38.126230.167.38.12762
155230.167.38.128/26230.167.38.129 to 230.167.38.190230.167.38.19162
156230.167.38.192/26230.167.38.193 to 230.167.38.254230.167.38.25562
157230.167.39.0/26230.167.39.1 to 230.167.39.62230.167.39.6362
158230.167.39.64/26230.167.39.65 to 230.167.39.126230.167.39.12762
159230.167.39.128/26230.167.39.129 to 230.167.39.190230.167.39.19162
160230.167.39.192/26230.167.39.193 to 230.167.39.254230.167.39.25562
161230.167.40.0/26230.167.40.1 to 230.167.40.62230.167.40.6362
162230.167.40.64/26230.167.40.65 to 230.167.40.126230.167.40.12762
163230.167.40.128/26230.167.40.129 to 230.167.40.190230.167.40.19162
164230.167.40.192/26230.167.40.193 to 230.167.40.254230.167.40.25562
165230.167.41.0/26230.167.41.1 to 230.167.41.62230.167.41.6362
166230.167.41.64/26230.167.41.65 to 230.167.41.126230.167.41.12762
167230.167.41.128/26230.167.41.129 to 230.167.41.190230.167.41.19162
168230.167.41.192/26230.167.41.193 to 230.167.41.254230.167.41.25562
169230.167.42.0/26230.167.42.1 to 230.167.42.62230.167.42.6362
170230.167.42.64/26230.167.42.65 to 230.167.42.126230.167.42.12762
171230.167.42.128/26230.167.42.129 to 230.167.42.190230.167.42.19162
172230.167.42.192/26230.167.42.193 to 230.167.42.254230.167.42.25562
173230.167.43.0/26230.167.43.1 to 230.167.43.62230.167.43.6362
174230.167.43.64/26230.167.43.65 to 230.167.43.126230.167.43.12762
175230.167.43.128/26230.167.43.129 to 230.167.43.190230.167.43.19162
176230.167.43.192/26230.167.43.193 to 230.167.43.254230.167.43.25562
177230.167.44.0/26230.167.44.1 to 230.167.44.62230.167.44.6362
178230.167.44.64/26230.167.44.65 to 230.167.44.126230.167.44.12762
179230.167.44.128/26230.167.44.129 to 230.167.44.190230.167.44.19162
180230.167.44.192/26230.167.44.193 to 230.167.44.254230.167.44.25562
181230.167.45.0/26230.167.45.1 to 230.167.45.62230.167.45.6362
182230.167.45.64/26230.167.45.65 to 230.167.45.126230.167.45.12762
183230.167.45.128/26230.167.45.129 to 230.167.45.190230.167.45.19162
184230.167.45.192/26230.167.45.193 to 230.167.45.254230.167.45.25562
185230.167.46.0/26230.167.46.1 to 230.167.46.62230.167.46.6362
186230.167.46.64/26230.167.46.65 to 230.167.46.126230.167.46.12762
187230.167.46.128/26230.167.46.129 to 230.167.46.190230.167.46.19162
188230.167.46.192/26230.167.46.193 to 230.167.46.254230.167.46.25562
189230.167.47.0/26230.167.47.1 to 230.167.47.62230.167.47.6362
190230.167.47.64/26230.167.47.65 to 230.167.47.126230.167.47.12762
191230.167.47.128/26230.167.47.129 to 230.167.47.190230.167.47.19162
192230.167.47.192/26230.167.47.193 to 230.167.47.254230.167.47.25562
193230.167.48.0/26230.167.48.1 to 230.167.48.62230.167.48.6362
194230.167.48.64/26230.167.48.65 to 230.167.48.126230.167.48.12762
195230.167.48.128/26230.167.48.129 to 230.167.48.190230.167.48.19162
196230.167.48.192/26230.167.48.193 to 230.167.48.254230.167.48.25562
197230.167.49.0/26230.167.49.1 to 230.167.49.62230.167.49.6362
198230.167.49.64/26230.167.49.65 to 230.167.49.126230.167.49.12762
199230.167.49.128/26230.167.49.129 to 230.167.49.190230.167.49.19162
200230.167.49.192/26230.167.49.193 to 230.167.49.254230.167.49.25562
201230.167.50.0/26230.167.50.1 to 230.167.50.62230.167.50.6362
202230.167.50.64/26230.167.50.65 to 230.167.50.126230.167.50.12762
203230.167.50.128/26230.167.50.129 to 230.167.50.190230.167.50.19162
204230.167.50.192/26230.167.50.193 to 230.167.50.254230.167.50.25562
205230.167.51.0/26230.167.51.1 to 230.167.51.62230.167.51.6362
206230.167.51.64/26230.167.51.65 to 230.167.51.126230.167.51.12762
207230.167.51.128/26230.167.51.129 to 230.167.51.190230.167.51.19162
208230.167.51.192/26230.167.51.193 to 230.167.51.254230.167.51.25562
209230.167.52.0/26230.167.52.1 to 230.167.52.62230.167.52.6362
210230.167.52.64/26230.167.52.65 to 230.167.52.126230.167.52.12762
211230.167.52.128/26230.167.52.129 to 230.167.52.190230.167.52.19162
212230.167.52.192/26230.167.52.193 to 230.167.52.254230.167.52.25562
213230.167.53.0/26230.167.53.1 to 230.167.53.62230.167.53.6362
214230.167.53.64/26230.167.53.65 to 230.167.53.126230.167.53.12762
215230.167.53.128/26230.167.53.129 to 230.167.53.190230.167.53.19162
216230.167.53.192/26230.167.53.193 to 230.167.53.254230.167.53.25562
217230.167.54.0/26230.167.54.1 to 230.167.54.62230.167.54.6362
218230.167.54.64/26230.167.54.65 to 230.167.54.126230.167.54.12762
219230.167.54.128/26230.167.54.129 to 230.167.54.190230.167.54.19162
220230.167.54.192/26230.167.54.193 to 230.167.54.254230.167.54.25562
221230.167.55.0/26230.167.55.1 to 230.167.55.62230.167.55.6362
222230.167.55.64/26230.167.55.65 to 230.167.55.126230.167.55.12762
223230.167.55.128/26230.167.55.129 to 230.167.55.190230.167.55.19162
224230.167.55.192/26230.167.55.193 to 230.167.55.254230.167.55.25562
225230.167.56.0/26230.167.56.1 to 230.167.56.62230.167.56.6362
226230.167.56.64/26230.167.56.65 to 230.167.56.126230.167.56.12762
227230.167.56.128/26230.167.56.129 to 230.167.56.190230.167.56.19162
228230.167.56.192/26230.167.56.193 to 230.167.56.254230.167.56.25562
229230.167.57.0/26230.167.57.1 to 230.167.57.62230.167.57.6362
230230.167.57.64/26230.167.57.65 to 230.167.57.126230.167.57.12762
231230.167.57.128/26230.167.57.129 to 230.167.57.190230.167.57.19162
232230.167.57.192/26230.167.57.193 to 230.167.57.254230.167.57.25562
233230.167.58.0/26230.167.58.1 to 230.167.58.62230.167.58.6362
234230.167.58.64/26230.167.58.65 to 230.167.58.126230.167.58.12762
235230.167.58.128/26230.167.58.129 to 230.167.58.190230.167.58.19162
236230.167.58.192/26230.167.58.193 to 230.167.58.254230.167.58.25562
237230.167.59.0/26230.167.59.1 to 230.167.59.62230.167.59.6362
238230.167.59.64/26230.167.59.65 to 230.167.59.126230.167.59.12762
239230.167.59.128/26230.167.59.129 to 230.167.59.190230.167.59.19162
240230.167.59.192/26230.167.59.193 to 230.167.59.254230.167.59.25562
241230.167.60.0/26230.167.60.1 to 230.167.60.62230.167.60.6362
242230.167.60.64/26230.167.60.65 to 230.167.60.126230.167.60.12762
243230.167.60.128/26230.167.60.129 to 230.167.60.190230.167.60.19162
244230.167.60.192/26230.167.60.193 to 230.167.60.254230.167.60.25562
245230.167.61.0/26230.167.61.1 to 230.167.61.62230.167.61.6362
246230.167.61.64/26230.167.61.65 to 230.167.61.126230.167.61.12762
247230.167.61.128/26230.167.61.129 to 230.167.61.190230.167.61.19162
248230.167.61.192/26230.167.61.193 to 230.167.61.254230.167.61.25562
249230.167.62.0/26230.167.62.1 to 230.167.62.62230.167.62.6362
250230.167.62.64/26230.167.62.65 to 230.167.62.126230.167.62.12762
251230.167.62.128/26230.167.62.129 to 230.167.62.190230.167.62.19162
252230.167.62.192/26230.167.62.193 to 230.167.62.254230.167.62.25562
253230.167.63.0/26230.167.63.1 to 230.167.63.62230.167.63.6362
254230.167.63.64/26230.167.63.65 to 230.167.63.126230.167.63.12762
255230.167.63.128/26230.167.63.129 to 230.167.63.190230.167.63.19162
256230.167.63.192/26230.167.63.193 to 230.167.63.254230.167.63.25562

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.