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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.

Network229.32.0.0/11
Usable hosts2,097,150
Subnet mask255.224.0.0
Addresses2,097,152
Network address
229.32.0.0
Broadcast address
229.63.255.255
First usable
229.32.0.1
Last usable
229.63.255.254
Usable hosts
2,097,150 (2,097,152 less the network and broadcast addresses)
Subnet mask
255.224.0.0
Wildcard mask
0.31.255.255 (Cisco ACLs, OSPF)
Prefix length
/11
Type
Multicast 224.0.0.0/4
One-to-many traffic, such as IPTV and routing protocols
Old class
D (multicast)
As numbers
Hex E5200000 · Integer 3844079616 to 3846176767
Reverse DNS zones
32.229.in-addr.arpa
33.229.in-addr.arpa
34.229.in-addr.arpa
35.229.in-addr.arpa
36.229.in-addr.arpa
37.229.in-addr.arpa
38.229.in-addr.arpa
39.229.in-addr.arpa
40.229.in-addr.arpa
41.229.in-addr.arpa
42.229.in-addr.arpa
43.229.in-addr.arpa
44.229.in-addr.arpa
45.229.in-addr.arpa
46.229.in-addr.arpa
47.229.in-addr.arpa
and 16 more
/11 is not on a 8-bit boundary, so it takes 32 /16 zones.
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address11100101.00100000.00000000.00000000229.32.0.0
Subnet mask11111111.11100000.00000000.00000000255.224.0.0
Network11100101.00100000.00000000.00000000229.32.0.0
Broadcast11100101.00111111.11111111.11111111229.63.255.255
Split into smaller subnets/19
/12 (2)/13 (4)/14 (8)/15 (16)/16 (32)/17 (64)/18 (128)/19 (256)/20 (512)/21 (1,024)/22 (2,048)/23 (4,096)

229.32.0.0/11 makes 256 subnets of /19.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
1229.32.0.0/19229.32.0.1 to 229.32.31.254229.32.31.2558,190
2229.32.32.0/19229.32.32.1 to 229.32.63.254229.32.63.2558,190
3229.32.64.0/19229.32.64.1 to 229.32.95.254229.32.95.2558,190
4229.32.96.0/19229.32.96.1 to 229.32.127.254229.32.127.2558,190
5229.32.128.0/19229.32.128.1 to 229.32.159.254229.32.159.2558,190
6229.32.160.0/19229.32.160.1 to 229.32.191.254229.32.191.2558,190
7229.32.192.0/19229.32.192.1 to 229.32.223.254229.32.223.2558,190
8229.32.224.0/19229.32.224.1 to 229.32.255.254229.32.255.2558,190
9229.33.0.0/19229.33.0.1 to 229.33.31.254229.33.31.2558,190
10229.33.32.0/19229.33.32.1 to 229.33.63.254229.33.63.2558,190
11229.33.64.0/19229.33.64.1 to 229.33.95.254229.33.95.2558,190
12229.33.96.0/19229.33.96.1 to 229.33.127.254229.33.127.2558,190
13229.33.128.0/19229.33.128.1 to 229.33.159.254229.33.159.2558,190
14229.33.160.0/19229.33.160.1 to 229.33.191.254229.33.191.2558,190
15229.33.192.0/19229.33.192.1 to 229.33.223.254229.33.223.2558,190
16229.33.224.0/19229.33.224.1 to 229.33.255.254229.33.255.2558,190
17229.34.0.0/19229.34.0.1 to 229.34.31.254229.34.31.2558,190
18229.34.32.0/19229.34.32.1 to 229.34.63.254229.34.63.2558,190
19229.34.64.0/19229.34.64.1 to 229.34.95.254229.34.95.2558,190
20229.34.96.0/19229.34.96.1 to 229.34.127.254229.34.127.2558,190
21229.34.128.0/19229.34.128.1 to 229.34.159.254229.34.159.2558,190
22229.34.160.0/19229.34.160.1 to 229.34.191.254229.34.191.2558,190
23229.34.192.0/19229.34.192.1 to 229.34.223.254229.34.223.2558,190
24229.34.224.0/19229.34.224.1 to 229.34.255.254229.34.255.2558,190
25229.35.0.0/19229.35.0.1 to 229.35.31.254229.35.31.2558,190
26229.35.32.0/19229.35.32.1 to 229.35.63.254229.35.63.2558,190
27229.35.64.0/19229.35.64.1 to 229.35.95.254229.35.95.2558,190
28229.35.96.0/19229.35.96.1 to 229.35.127.254229.35.127.2558,190
29229.35.128.0/19229.35.128.1 to 229.35.159.254229.35.159.2558,190
30229.35.160.0/19229.35.160.1 to 229.35.191.254229.35.191.2558,190
31229.35.192.0/19229.35.192.1 to 229.35.223.254229.35.223.2558,190
32229.35.224.0/19229.35.224.1 to 229.35.255.254229.35.255.2558,190
33229.36.0.0/19229.36.0.1 to 229.36.31.254229.36.31.2558,190
34229.36.32.0/19229.36.32.1 to 229.36.63.254229.36.63.2558,190
35229.36.64.0/19229.36.64.1 to 229.36.95.254229.36.95.2558,190
36229.36.96.0/19229.36.96.1 to 229.36.127.254229.36.127.2558,190
37229.36.128.0/19229.36.128.1 to 229.36.159.254229.36.159.2558,190
38229.36.160.0/19229.36.160.1 to 229.36.191.254229.36.191.2558,190
39229.36.192.0/19229.36.192.1 to 229.36.223.254229.36.223.2558,190
40229.36.224.0/19229.36.224.1 to 229.36.255.254229.36.255.2558,190
41229.37.0.0/19229.37.0.1 to 229.37.31.254229.37.31.2558,190
42229.37.32.0/19229.37.32.1 to 229.37.63.254229.37.63.2558,190
43229.37.64.0/19229.37.64.1 to 229.37.95.254229.37.95.2558,190
44229.37.96.0/19229.37.96.1 to 229.37.127.254229.37.127.2558,190
45229.37.128.0/19229.37.128.1 to 229.37.159.254229.37.159.2558,190
46229.37.160.0/19229.37.160.1 to 229.37.191.254229.37.191.2558,190
47229.37.192.0/19229.37.192.1 to 229.37.223.254229.37.223.2558,190
48229.37.224.0/19229.37.224.1 to 229.37.255.254229.37.255.2558,190
49229.38.0.0/19229.38.0.1 to 229.38.31.254229.38.31.2558,190
50229.38.32.0/19229.38.32.1 to 229.38.63.254229.38.63.2558,190
51229.38.64.0/19229.38.64.1 to 229.38.95.254229.38.95.2558,190
52229.38.96.0/19229.38.96.1 to 229.38.127.254229.38.127.2558,190
53229.38.128.0/19229.38.128.1 to 229.38.159.254229.38.159.2558,190
54229.38.160.0/19229.38.160.1 to 229.38.191.254229.38.191.2558,190
55229.38.192.0/19229.38.192.1 to 229.38.223.254229.38.223.2558,190
56229.38.224.0/19229.38.224.1 to 229.38.255.254229.38.255.2558,190
57229.39.0.0/19229.39.0.1 to 229.39.31.254229.39.31.2558,190
58229.39.32.0/19229.39.32.1 to 229.39.63.254229.39.63.2558,190
59229.39.64.0/19229.39.64.1 to 229.39.95.254229.39.95.2558,190
60229.39.96.0/19229.39.96.1 to 229.39.127.254229.39.127.2558,190
61229.39.128.0/19229.39.128.1 to 229.39.159.254229.39.159.2558,190
62229.39.160.0/19229.39.160.1 to 229.39.191.254229.39.191.2558,190
63229.39.192.0/19229.39.192.1 to 229.39.223.254229.39.223.2558,190
64229.39.224.0/19229.39.224.1 to 229.39.255.254229.39.255.2558,190
65229.40.0.0/19229.40.0.1 to 229.40.31.254229.40.31.2558,190
66229.40.32.0/19229.40.32.1 to 229.40.63.254229.40.63.2558,190
67229.40.64.0/19229.40.64.1 to 229.40.95.254229.40.95.2558,190
68229.40.96.0/19229.40.96.1 to 229.40.127.254229.40.127.2558,190
69229.40.128.0/19229.40.128.1 to 229.40.159.254229.40.159.2558,190
70229.40.160.0/19229.40.160.1 to 229.40.191.254229.40.191.2558,190
71229.40.192.0/19229.40.192.1 to 229.40.223.254229.40.223.2558,190
72229.40.224.0/19229.40.224.1 to 229.40.255.254229.40.255.2558,190
73229.41.0.0/19229.41.0.1 to 229.41.31.254229.41.31.2558,190
74229.41.32.0/19229.41.32.1 to 229.41.63.254229.41.63.2558,190
75229.41.64.0/19229.41.64.1 to 229.41.95.254229.41.95.2558,190
76229.41.96.0/19229.41.96.1 to 229.41.127.254229.41.127.2558,190
77229.41.128.0/19229.41.128.1 to 229.41.159.254229.41.159.2558,190
78229.41.160.0/19229.41.160.1 to 229.41.191.254229.41.191.2558,190
79229.41.192.0/19229.41.192.1 to 229.41.223.254229.41.223.2558,190
80229.41.224.0/19229.41.224.1 to 229.41.255.254229.41.255.2558,190
81229.42.0.0/19229.42.0.1 to 229.42.31.254229.42.31.2558,190
82229.42.32.0/19229.42.32.1 to 229.42.63.254229.42.63.2558,190
83229.42.64.0/19229.42.64.1 to 229.42.95.254229.42.95.2558,190
84229.42.96.0/19229.42.96.1 to 229.42.127.254229.42.127.2558,190
85229.42.128.0/19229.42.128.1 to 229.42.159.254229.42.159.2558,190
86229.42.160.0/19229.42.160.1 to 229.42.191.254229.42.191.2558,190
87229.42.192.0/19229.42.192.1 to 229.42.223.254229.42.223.2558,190
88229.42.224.0/19229.42.224.1 to 229.42.255.254229.42.255.2558,190
89229.43.0.0/19229.43.0.1 to 229.43.31.254229.43.31.2558,190
90229.43.32.0/19229.43.32.1 to 229.43.63.254229.43.63.2558,190
91229.43.64.0/19229.43.64.1 to 229.43.95.254229.43.95.2558,190
92229.43.96.0/19229.43.96.1 to 229.43.127.254229.43.127.2558,190
93229.43.128.0/19229.43.128.1 to 229.43.159.254229.43.159.2558,190
94229.43.160.0/19229.43.160.1 to 229.43.191.254229.43.191.2558,190
95229.43.192.0/19229.43.192.1 to 229.43.223.254229.43.223.2558,190
96229.43.224.0/19229.43.224.1 to 229.43.255.254229.43.255.2558,190
97229.44.0.0/19229.44.0.1 to 229.44.31.254229.44.31.2558,190
98229.44.32.0/19229.44.32.1 to 229.44.63.254229.44.63.2558,190
99229.44.64.0/19229.44.64.1 to 229.44.95.254229.44.95.2558,190
100229.44.96.0/19229.44.96.1 to 229.44.127.254229.44.127.2558,190
101229.44.128.0/19229.44.128.1 to 229.44.159.254229.44.159.2558,190
102229.44.160.0/19229.44.160.1 to 229.44.191.254229.44.191.2558,190
103229.44.192.0/19229.44.192.1 to 229.44.223.254229.44.223.2558,190
104229.44.224.0/19229.44.224.1 to 229.44.255.254229.44.255.2558,190
105229.45.0.0/19229.45.0.1 to 229.45.31.254229.45.31.2558,190
106229.45.32.0/19229.45.32.1 to 229.45.63.254229.45.63.2558,190
107229.45.64.0/19229.45.64.1 to 229.45.95.254229.45.95.2558,190
108229.45.96.0/19229.45.96.1 to 229.45.127.254229.45.127.2558,190
109229.45.128.0/19229.45.128.1 to 229.45.159.254229.45.159.2558,190
110229.45.160.0/19229.45.160.1 to 229.45.191.254229.45.191.2558,190
111229.45.192.0/19229.45.192.1 to 229.45.223.254229.45.223.2558,190
112229.45.224.0/19229.45.224.1 to 229.45.255.254229.45.255.2558,190
113229.46.0.0/19229.46.0.1 to 229.46.31.254229.46.31.2558,190
114229.46.32.0/19229.46.32.1 to 229.46.63.254229.46.63.2558,190
115229.46.64.0/19229.46.64.1 to 229.46.95.254229.46.95.2558,190
116229.46.96.0/19229.46.96.1 to 229.46.127.254229.46.127.2558,190
117229.46.128.0/19229.46.128.1 to 229.46.159.254229.46.159.2558,190
118229.46.160.0/19229.46.160.1 to 229.46.191.254229.46.191.2558,190
119229.46.192.0/19229.46.192.1 to 229.46.223.254229.46.223.2558,190
120229.46.224.0/19229.46.224.1 to 229.46.255.254229.46.255.2558,190
121229.47.0.0/19229.47.0.1 to 229.47.31.254229.47.31.2558,190
122229.47.32.0/19229.47.32.1 to 229.47.63.254229.47.63.2558,190
123229.47.64.0/19229.47.64.1 to 229.47.95.254229.47.95.2558,190
124229.47.96.0/19229.47.96.1 to 229.47.127.254229.47.127.2558,190
125229.47.128.0/19229.47.128.1 to 229.47.159.254229.47.159.2558,190
126229.47.160.0/19229.47.160.1 to 229.47.191.254229.47.191.2558,190
127229.47.192.0/19229.47.192.1 to 229.47.223.254229.47.223.2558,190
128229.47.224.0/19229.47.224.1 to 229.47.255.254229.47.255.2558,190
129229.48.0.0/19229.48.0.1 to 229.48.31.254229.48.31.2558,190
130229.48.32.0/19229.48.32.1 to 229.48.63.254229.48.63.2558,190
131229.48.64.0/19229.48.64.1 to 229.48.95.254229.48.95.2558,190
132229.48.96.0/19229.48.96.1 to 229.48.127.254229.48.127.2558,190
133229.48.128.0/19229.48.128.1 to 229.48.159.254229.48.159.2558,190
134229.48.160.0/19229.48.160.1 to 229.48.191.254229.48.191.2558,190
135229.48.192.0/19229.48.192.1 to 229.48.223.254229.48.223.2558,190
136229.48.224.0/19229.48.224.1 to 229.48.255.254229.48.255.2558,190
137229.49.0.0/19229.49.0.1 to 229.49.31.254229.49.31.2558,190
138229.49.32.0/19229.49.32.1 to 229.49.63.254229.49.63.2558,190
139229.49.64.0/19229.49.64.1 to 229.49.95.254229.49.95.2558,190
140229.49.96.0/19229.49.96.1 to 229.49.127.254229.49.127.2558,190
141229.49.128.0/19229.49.128.1 to 229.49.159.254229.49.159.2558,190
142229.49.160.0/19229.49.160.1 to 229.49.191.254229.49.191.2558,190
143229.49.192.0/19229.49.192.1 to 229.49.223.254229.49.223.2558,190
144229.49.224.0/19229.49.224.1 to 229.49.255.254229.49.255.2558,190
145229.50.0.0/19229.50.0.1 to 229.50.31.254229.50.31.2558,190
146229.50.32.0/19229.50.32.1 to 229.50.63.254229.50.63.2558,190
147229.50.64.0/19229.50.64.1 to 229.50.95.254229.50.95.2558,190
148229.50.96.0/19229.50.96.1 to 229.50.127.254229.50.127.2558,190
149229.50.128.0/19229.50.128.1 to 229.50.159.254229.50.159.2558,190
150229.50.160.0/19229.50.160.1 to 229.50.191.254229.50.191.2558,190
151229.50.192.0/19229.50.192.1 to 229.50.223.254229.50.223.2558,190
152229.50.224.0/19229.50.224.1 to 229.50.255.254229.50.255.2558,190
153229.51.0.0/19229.51.0.1 to 229.51.31.254229.51.31.2558,190
154229.51.32.0/19229.51.32.1 to 229.51.63.254229.51.63.2558,190
155229.51.64.0/19229.51.64.1 to 229.51.95.254229.51.95.2558,190
156229.51.96.0/19229.51.96.1 to 229.51.127.254229.51.127.2558,190
157229.51.128.0/19229.51.128.1 to 229.51.159.254229.51.159.2558,190
158229.51.160.0/19229.51.160.1 to 229.51.191.254229.51.191.2558,190
159229.51.192.0/19229.51.192.1 to 229.51.223.254229.51.223.2558,190
160229.51.224.0/19229.51.224.1 to 229.51.255.254229.51.255.2558,190
161229.52.0.0/19229.52.0.1 to 229.52.31.254229.52.31.2558,190
162229.52.32.0/19229.52.32.1 to 229.52.63.254229.52.63.2558,190
163229.52.64.0/19229.52.64.1 to 229.52.95.254229.52.95.2558,190
164229.52.96.0/19229.52.96.1 to 229.52.127.254229.52.127.2558,190
165229.52.128.0/19229.52.128.1 to 229.52.159.254229.52.159.2558,190
166229.52.160.0/19229.52.160.1 to 229.52.191.254229.52.191.2558,190
167229.52.192.0/19229.52.192.1 to 229.52.223.254229.52.223.2558,190
168229.52.224.0/19229.52.224.1 to 229.52.255.254229.52.255.2558,190
169229.53.0.0/19229.53.0.1 to 229.53.31.254229.53.31.2558,190
170229.53.32.0/19229.53.32.1 to 229.53.63.254229.53.63.2558,190
171229.53.64.0/19229.53.64.1 to 229.53.95.254229.53.95.2558,190
172229.53.96.0/19229.53.96.1 to 229.53.127.254229.53.127.2558,190
173229.53.128.0/19229.53.128.1 to 229.53.159.254229.53.159.2558,190
174229.53.160.0/19229.53.160.1 to 229.53.191.254229.53.191.2558,190
175229.53.192.0/19229.53.192.1 to 229.53.223.254229.53.223.2558,190
176229.53.224.0/19229.53.224.1 to 229.53.255.254229.53.255.2558,190
177229.54.0.0/19229.54.0.1 to 229.54.31.254229.54.31.2558,190
178229.54.32.0/19229.54.32.1 to 229.54.63.254229.54.63.2558,190
179229.54.64.0/19229.54.64.1 to 229.54.95.254229.54.95.2558,190
180229.54.96.0/19229.54.96.1 to 229.54.127.254229.54.127.2558,190
181229.54.128.0/19229.54.128.1 to 229.54.159.254229.54.159.2558,190
182229.54.160.0/19229.54.160.1 to 229.54.191.254229.54.191.2558,190
183229.54.192.0/19229.54.192.1 to 229.54.223.254229.54.223.2558,190
184229.54.224.0/19229.54.224.1 to 229.54.255.254229.54.255.2558,190
185229.55.0.0/19229.55.0.1 to 229.55.31.254229.55.31.2558,190
186229.55.32.0/19229.55.32.1 to 229.55.63.254229.55.63.2558,190
187229.55.64.0/19229.55.64.1 to 229.55.95.254229.55.95.2558,190
188229.55.96.0/19229.55.96.1 to 229.55.127.254229.55.127.2558,190
189229.55.128.0/19229.55.128.1 to 229.55.159.254229.55.159.2558,190
190229.55.160.0/19229.55.160.1 to 229.55.191.254229.55.191.2558,190
191229.55.192.0/19229.55.192.1 to 229.55.223.254229.55.223.2558,190
192229.55.224.0/19229.55.224.1 to 229.55.255.254229.55.255.2558,190
193229.56.0.0/19229.56.0.1 to 229.56.31.254229.56.31.2558,190
194229.56.32.0/19229.56.32.1 to 229.56.63.254229.56.63.2558,190
195229.56.64.0/19229.56.64.1 to 229.56.95.254229.56.95.2558,190
196229.56.96.0/19229.56.96.1 to 229.56.127.254229.56.127.2558,190
197229.56.128.0/19229.56.128.1 to 229.56.159.254229.56.159.2558,190
198229.56.160.0/19229.56.160.1 to 229.56.191.254229.56.191.2558,190
199229.56.192.0/19229.56.192.1 to 229.56.223.254229.56.223.2558,190
200229.56.224.0/19229.56.224.1 to 229.56.255.254229.56.255.2558,190
201229.57.0.0/19229.57.0.1 to 229.57.31.254229.57.31.2558,190
202229.57.32.0/19229.57.32.1 to 229.57.63.254229.57.63.2558,190
203229.57.64.0/19229.57.64.1 to 229.57.95.254229.57.95.2558,190
204229.57.96.0/19229.57.96.1 to 229.57.127.254229.57.127.2558,190
205229.57.128.0/19229.57.128.1 to 229.57.159.254229.57.159.2558,190
206229.57.160.0/19229.57.160.1 to 229.57.191.254229.57.191.2558,190
207229.57.192.0/19229.57.192.1 to 229.57.223.254229.57.223.2558,190
208229.57.224.0/19229.57.224.1 to 229.57.255.254229.57.255.2558,190
209229.58.0.0/19229.58.0.1 to 229.58.31.254229.58.31.2558,190
210229.58.32.0/19229.58.32.1 to 229.58.63.254229.58.63.2558,190
211229.58.64.0/19229.58.64.1 to 229.58.95.254229.58.95.2558,190
212229.58.96.0/19229.58.96.1 to 229.58.127.254229.58.127.2558,190
213229.58.128.0/19229.58.128.1 to 229.58.159.254229.58.159.2558,190
214229.58.160.0/19229.58.160.1 to 229.58.191.254229.58.191.2558,190
215229.58.192.0/19229.58.192.1 to 229.58.223.254229.58.223.2558,190
216229.58.224.0/19229.58.224.1 to 229.58.255.254229.58.255.2558,190
217229.59.0.0/19229.59.0.1 to 229.59.31.254229.59.31.2558,190
218229.59.32.0/19229.59.32.1 to 229.59.63.254229.59.63.2558,190
219229.59.64.0/19229.59.64.1 to 229.59.95.254229.59.95.2558,190
220229.59.96.0/19229.59.96.1 to 229.59.127.254229.59.127.2558,190
221229.59.128.0/19229.59.128.1 to 229.59.159.254229.59.159.2558,190
222229.59.160.0/19229.59.160.1 to 229.59.191.254229.59.191.2558,190
223229.59.192.0/19229.59.192.1 to 229.59.223.254229.59.223.2558,190
224229.59.224.0/19229.59.224.1 to 229.59.255.254229.59.255.2558,190
225229.60.0.0/19229.60.0.1 to 229.60.31.254229.60.31.2558,190
226229.60.32.0/19229.60.32.1 to 229.60.63.254229.60.63.2558,190
227229.60.64.0/19229.60.64.1 to 229.60.95.254229.60.95.2558,190
228229.60.96.0/19229.60.96.1 to 229.60.127.254229.60.127.2558,190
229229.60.128.0/19229.60.128.1 to 229.60.159.254229.60.159.2558,190
230229.60.160.0/19229.60.160.1 to 229.60.191.254229.60.191.2558,190
231229.60.192.0/19229.60.192.1 to 229.60.223.254229.60.223.2558,190
232229.60.224.0/19229.60.224.1 to 229.60.255.254229.60.255.2558,190
233229.61.0.0/19229.61.0.1 to 229.61.31.254229.61.31.2558,190
234229.61.32.0/19229.61.32.1 to 229.61.63.254229.61.63.2558,190
235229.61.64.0/19229.61.64.1 to 229.61.95.254229.61.95.2558,190
236229.61.96.0/19229.61.96.1 to 229.61.127.254229.61.127.2558,190
237229.61.128.0/19229.61.128.1 to 229.61.159.254229.61.159.2558,190
238229.61.160.0/19229.61.160.1 to 229.61.191.254229.61.191.2558,190
239229.61.192.0/19229.61.192.1 to 229.61.223.254229.61.223.2558,190
240229.61.224.0/19229.61.224.1 to 229.61.255.254229.61.255.2558,190
241229.62.0.0/19229.62.0.1 to 229.62.31.254229.62.31.2558,190
242229.62.32.0/19229.62.32.1 to 229.62.63.254229.62.63.2558,190
243229.62.64.0/19229.62.64.1 to 229.62.95.254229.62.95.2558,190
244229.62.96.0/19229.62.96.1 to 229.62.127.254229.62.127.2558,190
245229.62.128.0/19229.62.128.1 to 229.62.159.254229.62.159.2558,190
246229.62.160.0/19229.62.160.1 to 229.62.191.254229.62.191.2558,190
247229.62.192.0/19229.62.192.1 to 229.62.223.254229.62.223.2558,190
248229.62.224.0/19229.62.224.1 to 229.62.255.254229.62.255.2558,190
249229.63.0.0/19229.63.0.1 to 229.63.31.254229.63.31.2558,190
250229.63.32.0/19229.63.32.1 to 229.63.63.254229.63.63.2558,190
251229.63.64.0/19229.63.64.1 to 229.63.95.254229.63.95.2558,190
252229.63.96.0/19229.63.96.1 to 229.63.127.254229.63.127.2558,190
253229.63.128.0/19229.63.128.1 to 229.63.159.254229.63.159.2558,190
254229.63.160.0/19229.63.160.1 to 229.63.191.254229.63.191.2558,190
255229.63.192.0/19229.63.192.1 to 229.63.223.254229.63.223.2558,190
256229.63.224.0/19229.63.224.1 to 229.63.255.254229.63.255.2558,190

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.