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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.

Network229.0.0.0/8
Usable hosts16,777,214
Subnet mask255.0.0.0
Addresses16,777,216
Network address
229.0.0.0
Broadcast address
229.255.255.255
First usable
229.0.0.1
Last usable
229.255.255.254
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
Multicast 224.0.0.0/4
One-to-many traffic, such as IPTV and routing protocols
Old class
D (multicast)
As numbers
Hex E5000000 · Integer 3841982464 to 3858759679
Reverse DNS zone
229.in-addr.arpa
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address11100101..00000000.00000000.00000000229.0.0.0
Subnet mask11111111..00000000.00000000.00000000255.0.0.0
Network11100101..00000000.00000000.00000000229.0.0.0
Broadcast11100101..11111111.11111111.11111111229.255.255.255
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)

229.0.0.0/8 makes 1,024 subnets of /18; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
1229.0.0.0/18229.0.0.1 to 229.0.63.254229.0.63.25516,382
2229.0.64.0/18229.0.64.1 to 229.0.127.254229.0.127.25516,382
3229.0.128.0/18229.0.128.1 to 229.0.191.254229.0.191.25516,382
4229.0.192.0/18229.0.192.1 to 229.0.255.254229.0.255.25516,382
5229.1.0.0/18229.1.0.1 to 229.1.63.254229.1.63.25516,382
6229.1.64.0/18229.1.64.1 to 229.1.127.254229.1.127.25516,382
7229.1.128.0/18229.1.128.1 to 229.1.191.254229.1.191.25516,382
8229.1.192.0/18229.1.192.1 to 229.1.255.254229.1.255.25516,382
9229.2.0.0/18229.2.0.1 to 229.2.63.254229.2.63.25516,382
10229.2.64.0/18229.2.64.1 to 229.2.127.254229.2.127.25516,382
11229.2.128.0/18229.2.128.1 to 229.2.191.254229.2.191.25516,382
12229.2.192.0/18229.2.192.1 to 229.2.255.254229.2.255.25516,382
13229.3.0.0/18229.3.0.1 to 229.3.63.254229.3.63.25516,382
14229.3.64.0/18229.3.64.1 to 229.3.127.254229.3.127.25516,382
15229.3.128.0/18229.3.128.1 to 229.3.191.254229.3.191.25516,382
16229.3.192.0/18229.3.192.1 to 229.3.255.254229.3.255.25516,382
17229.4.0.0/18229.4.0.1 to 229.4.63.254229.4.63.25516,382
18229.4.64.0/18229.4.64.1 to 229.4.127.254229.4.127.25516,382
19229.4.128.0/18229.4.128.1 to 229.4.191.254229.4.191.25516,382
20229.4.192.0/18229.4.192.1 to 229.4.255.254229.4.255.25516,382
21229.5.0.0/18229.5.0.1 to 229.5.63.254229.5.63.25516,382
22229.5.64.0/18229.5.64.1 to 229.5.127.254229.5.127.25516,382
23229.5.128.0/18229.5.128.1 to 229.5.191.254229.5.191.25516,382
24229.5.192.0/18229.5.192.1 to 229.5.255.254229.5.255.25516,382
25229.6.0.0/18229.6.0.1 to 229.6.63.254229.6.63.25516,382
26229.6.64.0/18229.6.64.1 to 229.6.127.254229.6.127.25516,382
27229.6.128.0/18229.6.128.1 to 229.6.191.254229.6.191.25516,382
28229.6.192.0/18229.6.192.1 to 229.6.255.254229.6.255.25516,382
29229.7.0.0/18229.7.0.1 to 229.7.63.254229.7.63.25516,382
30229.7.64.0/18229.7.64.1 to 229.7.127.254229.7.127.25516,382
31229.7.128.0/18229.7.128.1 to 229.7.191.254229.7.191.25516,382
32229.7.192.0/18229.7.192.1 to 229.7.255.254229.7.255.25516,382
33229.8.0.0/18229.8.0.1 to 229.8.63.254229.8.63.25516,382
34229.8.64.0/18229.8.64.1 to 229.8.127.254229.8.127.25516,382
35229.8.128.0/18229.8.128.1 to 229.8.191.254229.8.191.25516,382
36229.8.192.0/18229.8.192.1 to 229.8.255.254229.8.255.25516,382
37229.9.0.0/18229.9.0.1 to 229.9.63.254229.9.63.25516,382
38229.9.64.0/18229.9.64.1 to 229.9.127.254229.9.127.25516,382
39229.9.128.0/18229.9.128.1 to 229.9.191.254229.9.191.25516,382
40229.9.192.0/18229.9.192.1 to 229.9.255.254229.9.255.25516,382
41229.10.0.0/18229.10.0.1 to 229.10.63.254229.10.63.25516,382
42229.10.64.0/18229.10.64.1 to 229.10.127.254229.10.127.25516,382
43229.10.128.0/18229.10.128.1 to 229.10.191.254229.10.191.25516,382
44229.10.192.0/18229.10.192.1 to 229.10.255.254229.10.255.25516,382
45229.11.0.0/18229.11.0.1 to 229.11.63.254229.11.63.25516,382
46229.11.64.0/18229.11.64.1 to 229.11.127.254229.11.127.25516,382
47229.11.128.0/18229.11.128.1 to 229.11.191.254229.11.191.25516,382
48229.11.192.0/18229.11.192.1 to 229.11.255.254229.11.255.25516,382
49229.12.0.0/18229.12.0.1 to 229.12.63.254229.12.63.25516,382
50229.12.64.0/18229.12.64.1 to 229.12.127.254229.12.127.25516,382
51229.12.128.0/18229.12.128.1 to 229.12.191.254229.12.191.25516,382
52229.12.192.0/18229.12.192.1 to 229.12.255.254229.12.255.25516,382
53229.13.0.0/18229.13.0.1 to 229.13.63.254229.13.63.25516,382
54229.13.64.0/18229.13.64.1 to 229.13.127.254229.13.127.25516,382
55229.13.128.0/18229.13.128.1 to 229.13.191.254229.13.191.25516,382
56229.13.192.0/18229.13.192.1 to 229.13.255.254229.13.255.25516,382
57229.14.0.0/18229.14.0.1 to 229.14.63.254229.14.63.25516,382
58229.14.64.0/18229.14.64.1 to 229.14.127.254229.14.127.25516,382
59229.14.128.0/18229.14.128.1 to 229.14.191.254229.14.191.25516,382
60229.14.192.0/18229.14.192.1 to 229.14.255.254229.14.255.25516,382
61229.15.0.0/18229.15.0.1 to 229.15.63.254229.15.63.25516,382
62229.15.64.0/18229.15.64.1 to 229.15.127.254229.15.127.25516,382
63229.15.128.0/18229.15.128.1 to 229.15.191.254229.15.191.25516,382
64229.15.192.0/18229.15.192.1 to 229.15.255.254229.15.255.25516,382
65229.16.0.0/18229.16.0.1 to 229.16.63.254229.16.63.25516,382
66229.16.64.0/18229.16.64.1 to 229.16.127.254229.16.127.25516,382
67229.16.128.0/18229.16.128.1 to 229.16.191.254229.16.191.25516,382
68229.16.192.0/18229.16.192.1 to 229.16.255.254229.16.255.25516,382
69229.17.0.0/18229.17.0.1 to 229.17.63.254229.17.63.25516,382
70229.17.64.0/18229.17.64.1 to 229.17.127.254229.17.127.25516,382
71229.17.128.0/18229.17.128.1 to 229.17.191.254229.17.191.25516,382
72229.17.192.0/18229.17.192.1 to 229.17.255.254229.17.255.25516,382
73229.18.0.0/18229.18.0.1 to 229.18.63.254229.18.63.25516,382
74229.18.64.0/18229.18.64.1 to 229.18.127.254229.18.127.25516,382
75229.18.128.0/18229.18.128.1 to 229.18.191.254229.18.191.25516,382
76229.18.192.0/18229.18.192.1 to 229.18.255.254229.18.255.25516,382
77229.19.0.0/18229.19.0.1 to 229.19.63.254229.19.63.25516,382
78229.19.64.0/18229.19.64.1 to 229.19.127.254229.19.127.25516,382
79229.19.128.0/18229.19.128.1 to 229.19.191.254229.19.191.25516,382
80229.19.192.0/18229.19.192.1 to 229.19.255.254229.19.255.25516,382
81229.20.0.0/18229.20.0.1 to 229.20.63.254229.20.63.25516,382
82229.20.64.0/18229.20.64.1 to 229.20.127.254229.20.127.25516,382
83229.20.128.0/18229.20.128.1 to 229.20.191.254229.20.191.25516,382
84229.20.192.0/18229.20.192.1 to 229.20.255.254229.20.255.25516,382
85229.21.0.0/18229.21.0.1 to 229.21.63.254229.21.63.25516,382
86229.21.64.0/18229.21.64.1 to 229.21.127.254229.21.127.25516,382
87229.21.128.0/18229.21.128.1 to 229.21.191.254229.21.191.25516,382
88229.21.192.0/18229.21.192.1 to 229.21.255.254229.21.255.25516,382
89229.22.0.0/18229.22.0.1 to 229.22.63.254229.22.63.25516,382
90229.22.64.0/18229.22.64.1 to 229.22.127.254229.22.127.25516,382
91229.22.128.0/18229.22.128.1 to 229.22.191.254229.22.191.25516,382
92229.22.192.0/18229.22.192.1 to 229.22.255.254229.22.255.25516,382
93229.23.0.0/18229.23.0.1 to 229.23.63.254229.23.63.25516,382
94229.23.64.0/18229.23.64.1 to 229.23.127.254229.23.127.25516,382
95229.23.128.0/18229.23.128.1 to 229.23.191.254229.23.191.25516,382
96229.23.192.0/18229.23.192.1 to 229.23.255.254229.23.255.25516,382
97229.24.0.0/18229.24.0.1 to 229.24.63.254229.24.63.25516,382
98229.24.64.0/18229.24.64.1 to 229.24.127.254229.24.127.25516,382
99229.24.128.0/18229.24.128.1 to 229.24.191.254229.24.191.25516,382
100229.24.192.0/18229.24.192.1 to 229.24.255.254229.24.255.25516,382
101229.25.0.0/18229.25.0.1 to 229.25.63.254229.25.63.25516,382
102229.25.64.0/18229.25.64.1 to 229.25.127.254229.25.127.25516,382
103229.25.128.0/18229.25.128.1 to 229.25.191.254229.25.191.25516,382
104229.25.192.0/18229.25.192.1 to 229.25.255.254229.25.255.25516,382
105229.26.0.0/18229.26.0.1 to 229.26.63.254229.26.63.25516,382
106229.26.64.0/18229.26.64.1 to 229.26.127.254229.26.127.25516,382
107229.26.128.0/18229.26.128.1 to 229.26.191.254229.26.191.25516,382
108229.26.192.0/18229.26.192.1 to 229.26.255.254229.26.255.25516,382
109229.27.0.0/18229.27.0.1 to 229.27.63.254229.27.63.25516,382
110229.27.64.0/18229.27.64.1 to 229.27.127.254229.27.127.25516,382
111229.27.128.0/18229.27.128.1 to 229.27.191.254229.27.191.25516,382
112229.27.192.0/18229.27.192.1 to 229.27.255.254229.27.255.25516,382
113229.28.0.0/18229.28.0.1 to 229.28.63.254229.28.63.25516,382
114229.28.64.0/18229.28.64.1 to 229.28.127.254229.28.127.25516,382
115229.28.128.0/18229.28.128.1 to 229.28.191.254229.28.191.25516,382
116229.28.192.0/18229.28.192.1 to 229.28.255.254229.28.255.25516,382
117229.29.0.0/18229.29.0.1 to 229.29.63.254229.29.63.25516,382
118229.29.64.0/18229.29.64.1 to 229.29.127.254229.29.127.25516,382
119229.29.128.0/18229.29.128.1 to 229.29.191.254229.29.191.25516,382
120229.29.192.0/18229.29.192.1 to 229.29.255.254229.29.255.25516,382
121229.30.0.0/18229.30.0.1 to 229.30.63.254229.30.63.25516,382
122229.30.64.0/18229.30.64.1 to 229.30.127.254229.30.127.25516,382
123229.30.128.0/18229.30.128.1 to 229.30.191.254229.30.191.25516,382
124229.30.192.0/18229.30.192.1 to 229.30.255.254229.30.255.25516,382
125229.31.0.0/18229.31.0.1 to 229.31.63.254229.31.63.25516,382
126229.31.64.0/18229.31.64.1 to 229.31.127.254229.31.127.25516,382
127229.31.128.0/18229.31.128.1 to 229.31.191.254229.31.191.25516,382
128229.31.192.0/18229.31.192.1 to 229.31.255.254229.31.255.25516,382
129229.32.0.0/18229.32.0.1 to 229.32.63.254229.32.63.25516,382
130229.32.64.0/18229.32.64.1 to 229.32.127.254229.32.127.25516,382
131229.32.128.0/18229.32.128.1 to 229.32.191.254229.32.191.25516,382
132229.32.192.0/18229.32.192.1 to 229.32.255.254229.32.255.25516,382
133229.33.0.0/18229.33.0.1 to 229.33.63.254229.33.63.25516,382
134229.33.64.0/18229.33.64.1 to 229.33.127.254229.33.127.25516,382
135229.33.128.0/18229.33.128.1 to 229.33.191.254229.33.191.25516,382
136229.33.192.0/18229.33.192.1 to 229.33.255.254229.33.255.25516,382
137229.34.0.0/18229.34.0.1 to 229.34.63.254229.34.63.25516,382
138229.34.64.0/18229.34.64.1 to 229.34.127.254229.34.127.25516,382
139229.34.128.0/18229.34.128.1 to 229.34.191.254229.34.191.25516,382
140229.34.192.0/18229.34.192.1 to 229.34.255.254229.34.255.25516,382
141229.35.0.0/18229.35.0.1 to 229.35.63.254229.35.63.25516,382
142229.35.64.0/18229.35.64.1 to 229.35.127.254229.35.127.25516,382
143229.35.128.0/18229.35.128.1 to 229.35.191.254229.35.191.25516,382
144229.35.192.0/18229.35.192.1 to 229.35.255.254229.35.255.25516,382
145229.36.0.0/18229.36.0.1 to 229.36.63.254229.36.63.25516,382
146229.36.64.0/18229.36.64.1 to 229.36.127.254229.36.127.25516,382
147229.36.128.0/18229.36.128.1 to 229.36.191.254229.36.191.25516,382
148229.36.192.0/18229.36.192.1 to 229.36.255.254229.36.255.25516,382
149229.37.0.0/18229.37.0.1 to 229.37.63.254229.37.63.25516,382
150229.37.64.0/18229.37.64.1 to 229.37.127.254229.37.127.25516,382
151229.37.128.0/18229.37.128.1 to 229.37.191.254229.37.191.25516,382
152229.37.192.0/18229.37.192.1 to 229.37.255.254229.37.255.25516,382
153229.38.0.0/18229.38.0.1 to 229.38.63.254229.38.63.25516,382
154229.38.64.0/18229.38.64.1 to 229.38.127.254229.38.127.25516,382
155229.38.128.0/18229.38.128.1 to 229.38.191.254229.38.191.25516,382
156229.38.192.0/18229.38.192.1 to 229.38.255.254229.38.255.25516,382
157229.39.0.0/18229.39.0.1 to 229.39.63.254229.39.63.25516,382
158229.39.64.0/18229.39.64.1 to 229.39.127.254229.39.127.25516,382
159229.39.128.0/18229.39.128.1 to 229.39.191.254229.39.191.25516,382
160229.39.192.0/18229.39.192.1 to 229.39.255.254229.39.255.25516,382
161229.40.0.0/18229.40.0.1 to 229.40.63.254229.40.63.25516,382
162229.40.64.0/18229.40.64.1 to 229.40.127.254229.40.127.25516,382
163229.40.128.0/18229.40.128.1 to 229.40.191.254229.40.191.25516,382
164229.40.192.0/18229.40.192.1 to 229.40.255.254229.40.255.25516,382
165229.41.0.0/18229.41.0.1 to 229.41.63.254229.41.63.25516,382
166229.41.64.0/18229.41.64.1 to 229.41.127.254229.41.127.25516,382
167229.41.128.0/18229.41.128.1 to 229.41.191.254229.41.191.25516,382
168229.41.192.0/18229.41.192.1 to 229.41.255.254229.41.255.25516,382
169229.42.0.0/18229.42.0.1 to 229.42.63.254229.42.63.25516,382
170229.42.64.0/18229.42.64.1 to 229.42.127.254229.42.127.25516,382
171229.42.128.0/18229.42.128.1 to 229.42.191.254229.42.191.25516,382
172229.42.192.0/18229.42.192.1 to 229.42.255.254229.42.255.25516,382
173229.43.0.0/18229.43.0.1 to 229.43.63.254229.43.63.25516,382
174229.43.64.0/18229.43.64.1 to 229.43.127.254229.43.127.25516,382
175229.43.128.0/18229.43.128.1 to 229.43.191.254229.43.191.25516,382
176229.43.192.0/18229.43.192.1 to 229.43.255.254229.43.255.25516,382
177229.44.0.0/18229.44.0.1 to 229.44.63.254229.44.63.25516,382
178229.44.64.0/18229.44.64.1 to 229.44.127.254229.44.127.25516,382
179229.44.128.0/18229.44.128.1 to 229.44.191.254229.44.191.25516,382
180229.44.192.0/18229.44.192.1 to 229.44.255.254229.44.255.25516,382
181229.45.0.0/18229.45.0.1 to 229.45.63.254229.45.63.25516,382
182229.45.64.0/18229.45.64.1 to 229.45.127.254229.45.127.25516,382
183229.45.128.0/18229.45.128.1 to 229.45.191.254229.45.191.25516,382
184229.45.192.0/18229.45.192.1 to 229.45.255.254229.45.255.25516,382
185229.46.0.0/18229.46.0.1 to 229.46.63.254229.46.63.25516,382
186229.46.64.0/18229.46.64.1 to 229.46.127.254229.46.127.25516,382
187229.46.128.0/18229.46.128.1 to 229.46.191.254229.46.191.25516,382
188229.46.192.0/18229.46.192.1 to 229.46.255.254229.46.255.25516,382
189229.47.0.0/18229.47.0.1 to 229.47.63.254229.47.63.25516,382
190229.47.64.0/18229.47.64.1 to 229.47.127.254229.47.127.25516,382
191229.47.128.0/18229.47.128.1 to 229.47.191.254229.47.191.25516,382
192229.47.192.0/18229.47.192.1 to 229.47.255.254229.47.255.25516,382
193229.48.0.0/18229.48.0.1 to 229.48.63.254229.48.63.25516,382
194229.48.64.0/18229.48.64.1 to 229.48.127.254229.48.127.25516,382
195229.48.128.0/18229.48.128.1 to 229.48.191.254229.48.191.25516,382
196229.48.192.0/18229.48.192.1 to 229.48.255.254229.48.255.25516,382
197229.49.0.0/18229.49.0.1 to 229.49.63.254229.49.63.25516,382
198229.49.64.0/18229.49.64.1 to 229.49.127.254229.49.127.25516,382
199229.49.128.0/18229.49.128.1 to 229.49.191.254229.49.191.25516,382
200229.49.192.0/18229.49.192.1 to 229.49.255.254229.49.255.25516,382
201229.50.0.0/18229.50.0.1 to 229.50.63.254229.50.63.25516,382
202229.50.64.0/18229.50.64.1 to 229.50.127.254229.50.127.25516,382
203229.50.128.0/18229.50.128.1 to 229.50.191.254229.50.191.25516,382
204229.50.192.0/18229.50.192.1 to 229.50.255.254229.50.255.25516,382
205229.51.0.0/18229.51.0.1 to 229.51.63.254229.51.63.25516,382
206229.51.64.0/18229.51.64.1 to 229.51.127.254229.51.127.25516,382
207229.51.128.0/18229.51.128.1 to 229.51.191.254229.51.191.25516,382
208229.51.192.0/18229.51.192.1 to 229.51.255.254229.51.255.25516,382
209229.52.0.0/18229.52.0.1 to 229.52.63.254229.52.63.25516,382
210229.52.64.0/18229.52.64.1 to 229.52.127.254229.52.127.25516,382
211229.52.128.0/18229.52.128.1 to 229.52.191.254229.52.191.25516,382
212229.52.192.0/18229.52.192.1 to 229.52.255.254229.52.255.25516,382
213229.53.0.0/18229.53.0.1 to 229.53.63.254229.53.63.25516,382
214229.53.64.0/18229.53.64.1 to 229.53.127.254229.53.127.25516,382
215229.53.128.0/18229.53.128.1 to 229.53.191.254229.53.191.25516,382
216229.53.192.0/18229.53.192.1 to 229.53.255.254229.53.255.25516,382
217229.54.0.0/18229.54.0.1 to 229.54.63.254229.54.63.25516,382
218229.54.64.0/18229.54.64.1 to 229.54.127.254229.54.127.25516,382
219229.54.128.0/18229.54.128.1 to 229.54.191.254229.54.191.25516,382
220229.54.192.0/18229.54.192.1 to 229.54.255.254229.54.255.25516,382
221229.55.0.0/18229.55.0.1 to 229.55.63.254229.55.63.25516,382
222229.55.64.0/18229.55.64.1 to 229.55.127.254229.55.127.25516,382
223229.55.128.0/18229.55.128.1 to 229.55.191.254229.55.191.25516,382
224229.55.192.0/18229.55.192.1 to 229.55.255.254229.55.255.25516,382
225229.56.0.0/18229.56.0.1 to 229.56.63.254229.56.63.25516,382
226229.56.64.0/18229.56.64.1 to 229.56.127.254229.56.127.25516,382
227229.56.128.0/18229.56.128.1 to 229.56.191.254229.56.191.25516,382
228229.56.192.0/18229.56.192.1 to 229.56.255.254229.56.255.25516,382
229229.57.0.0/18229.57.0.1 to 229.57.63.254229.57.63.25516,382
230229.57.64.0/18229.57.64.1 to 229.57.127.254229.57.127.25516,382
231229.57.128.0/18229.57.128.1 to 229.57.191.254229.57.191.25516,382
232229.57.192.0/18229.57.192.1 to 229.57.255.254229.57.255.25516,382
233229.58.0.0/18229.58.0.1 to 229.58.63.254229.58.63.25516,382
234229.58.64.0/18229.58.64.1 to 229.58.127.254229.58.127.25516,382
235229.58.128.0/18229.58.128.1 to 229.58.191.254229.58.191.25516,382
236229.58.192.0/18229.58.192.1 to 229.58.255.254229.58.255.25516,382
237229.59.0.0/18229.59.0.1 to 229.59.63.254229.59.63.25516,382
238229.59.64.0/18229.59.64.1 to 229.59.127.254229.59.127.25516,382
239229.59.128.0/18229.59.128.1 to 229.59.191.254229.59.191.25516,382
240229.59.192.0/18229.59.192.1 to 229.59.255.254229.59.255.25516,382
241229.60.0.0/18229.60.0.1 to 229.60.63.254229.60.63.25516,382
242229.60.64.0/18229.60.64.1 to 229.60.127.254229.60.127.25516,382
243229.60.128.0/18229.60.128.1 to 229.60.191.254229.60.191.25516,382
244229.60.192.0/18229.60.192.1 to 229.60.255.254229.60.255.25516,382
245229.61.0.0/18229.61.0.1 to 229.61.63.254229.61.63.25516,382
246229.61.64.0/18229.61.64.1 to 229.61.127.254229.61.127.25516,382
247229.61.128.0/18229.61.128.1 to 229.61.191.254229.61.191.25516,382
248229.61.192.0/18229.61.192.1 to 229.61.255.254229.61.255.25516,382
249229.62.0.0/18229.62.0.1 to 229.62.63.254229.62.63.25516,382
250229.62.64.0/18229.62.64.1 to 229.62.127.254229.62.127.25516,382
251229.62.128.0/18229.62.128.1 to 229.62.191.254229.62.191.25516,382
252229.62.192.0/18229.62.192.1 to 229.62.255.254229.62.255.25516,382
253229.63.0.0/18229.63.0.1 to 229.63.63.254229.63.63.25516,382
254229.63.64.0/18229.63.64.1 to 229.63.127.254229.63.127.25516,382
255229.63.128.0/18229.63.128.1 to 229.63.191.254229.63.191.25516,382
256229.63.192.0/18229.63.192.1 to 229.63.255.254229.63.255.25516,382

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.