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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.

Network235.128.0.0/11
Usable hosts2,097,150
Subnet mask255.224.0.0
Addresses2,097,152
Network address
235.128.0.0
Broadcast address
235.159.255.255
First usable
235.128.0.1
Last usable
235.159.255.254
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 EB800000 · Integer 3951034368 to 3953131519
Reverse DNS zones
128.235.in-addr.arpa
129.235.in-addr.arpa
130.235.in-addr.arpa
131.235.in-addr.arpa
132.235.in-addr.arpa
133.235.in-addr.arpa
134.235.in-addr.arpa
135.235.in-addr.arpa
136.235.in-addr.arpa
137.235.in-addr.arpa
138.235.in-addr.arpa
139.235.in-addr.arpa
140.235.in-addr.arpa
141.235.in-addr.arpa
142.235.in-addr.arpa
143.235.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
Address11101011.10000000.00000000.00000000235.128.0.0
Subnet mask11111111.11100000.00000000.00000000255.224.0.0
Network11101011.10000000.00000000.00000000235.128.0.0
Broadcast11101011.10011111.11111111.11111111235.159.255.255
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)

235.128.0.0/11 makes 256 subnets of /19.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
1235.128.0.0/19235.128.0.1 to 235.128.31.254235.128.31.2558,190
2235.128.32.0/19235.128.32.1 to 235.128.63.254235.128.63.2558,190
3235.128.64.0/19235.128.64.1 to 235.128.95.254235.128.95.2558,190
4235.128.96.0/19235.128.96.1 to 235.128.127.254235.128.127.2558,190
5235.128.128.0/19235.128.128.1 to 235.128.159.254235.128.159.2558,190
6235.128.160.0/19235.128.160.1 to 235.128.191.254235.128.191.2558,190
7235.128.192.0/19235.128.192.1 to 235.128.223.254235.128.223.2558,190
8235.128.224.0/19235.128.224.1 to 235.128.255.254235.128.255.2558,190
9235.129.0.0/19235.129.0.1 to 235.129.31.254235.129.31.2558,190
10235.129.32.0/19235.129.32.1 to 235.129.63.254235.129.63.2558,190
11235.129.64.0/19235.129.64.1 to 235.129.95.254235.129.95.2558,190
12235.129.96.0/19235.129.96.1 to 235.129.127.254235.129.127.2558,190
13235.129.128.0/19235.129.128.1 to 235.129.159.254235.129.159.2558,190
14235.129.160.0/19235.129.160.1 to 235.129.191.254235.129.191.2558,190
15235.129.192.0/19235.129.192.1 to 235.129.223.254235.129.223.2558,190
16235.129.224.0/19235.129.224.1 to 235.129.255.254235.129.255.2558,190
17235.130.0.0/19235.130.0.1 to 235.130.31.254235.130.31.2558,190
18235.130.32.0/19235.130.32.1 to 235.130.63.254235.130.63.2558,190
19235.130.64.0/19235.130.64.1 to 235.130.95.254235.130.95.2558,190
20235.130.96.0/19235.130.96.1 to 235.130.127.254235.130.127.2558,190
21235.130.128.0/19235.130.128.1 to 235.130.159.254235.130.159.2558,190
22235.130.160.0/19235.130.160.1 to 235.130.191.254235.130.191.2558,190
23235.130.192.0/19235.130.192.1 to 235.130.223.254235.130.223.2558,190
24235.130.224.0/19235.130.224.1 to 235.130.255.254235.130.255.2558,190
25235.131.0.0/19235.131.0.1 to 235.131.31.254235.131.31.2558,190
26235.131.32.0/19235.131.32.1 to 235.131.63.254235.131.63.2558,190
27235.131.64.0/19235.131.64.1 to 235.131.95.254235.131.95.2558,190
28235.131.96.0/19235.131.96.1 to 235.131.127.254235.131.127.2558,190
29235.131.128.0/19235.131.128.1 to 235.131.159.254235.131.159.2558,190
30235.131.160.0/19235.131.160.1 to 235.131.191.254235.131.191.2558,190
31235.131.192.0/19235.131.192.1 to 235.131.223.254235.131.223.2558,190
32235.131.224.0/19235.131.224.1 to 235.131.255.254235.131.255.2558,190
33235.132.0.0/19235.132.0.1 to 235.132.31.254235.132.31.2558,190
34235.132.32.0/19235.132.32.1 to 235.132.63.254235.132.63.2558,190
35235.132.64.0/19235.132.64.1 to 235.132.95.254235.132.95.2558,190
36235.132.96.0/19235.132.96.1 to 235.132.127.254235.132.127.2558,190
37235.132.128.0/19235.132.128.1 to 235.132.159.254235.132.159.2558,190
38235.132.160.0/19235.132.160.1 to 235.132.191.254235.132.191.2558,190
39235.132.192.0/19235.132.192.1 to 235.132.223.254235.132.223.2558,190
40235.132.224.0/19235.132.224.1 to 235.132.255.254235.132.255.2558,190
41235.133.0.0/19235.133.0.1 to 235.133.31.254235.133.31.2558,190
42235.133.32.0/19235.133.32.1 to 235.133.63.254235.133.63.2558,190
43235.133.64.0/19235.133.64.1 to 235.133.95.254235.133.95.2558,190
44235.133.96.0/19235.133.96.1 to 235.133.127.254235.133.127.2558,190
45235.133.128.0/19235.133.128.1 to 235.133.159.254235.133.159.2558,190
46235.133.160.0/19235.133.160.1 to 235.133.191.254235.133.191.2558,190
47235.133.192.0/19235.133.192.1 to 235.133.223.254235.133.223.2558,190
48235.133.224.0/19235.133.224.1 to 235.133.255.254235.133.255.2558,190
49235.134.0.0/19235.134.0.1 to 235.134.31.254235.134.31.2558,190
50235.134.32.0/19235.134.32.1 to 235.134.63.254235.134.63.2558,190
51235.134.64.0/19235.134.64.1 to 235.134.95.254235.134.95.2558,190
52235.134.96.0/19235.134.96.1 to 235.134.127.254235.134.127.2558,190
53235.134.128.0/19235.134.128.1 to 235.134.159.254235.134.159.2558,190
54235.134.160.0/19235.134.160.1 to 235.134.191.254235.134.191.2558,190
55235.134.192.0/19235.134.192.1 to 235.134.223.254235.134.223.2558,190
56235.134.224.0/19235.134.224.1 to 235.134.255.254235.134.255.2558,190
57235.135.0.0/19235.135.0.1 to 235.135.31.254235.135.31.2558,190
58235.135.32.0/19235.135.32.1 to 235.135.63.254235.135.63.2558,190
59235.135.64.0/19235.135.64.1 to 235.135.95.254235.135.95.2558,190
60235.135.96.0/19235.135.96.1 to 235.135.127.254235.135.127.2558,190
61235.135.128.0/19235.135.128.1 to 235.135.159.254235.135.159.2558,190
62235.135.160.0/19235.135.160.1 to 235.135.191.254235.135.191.2558,190
63235.135.192.0/19235.135.192.1 to 235.135.223.254235.135.223.2558,190
64235.135.224.0/19235.135.224.1 to 235.135.255.254235.135.255.2558,190
65235.136.0.0/19235.136.0.1 to 235.136.31.254235.136.31.2558,190
66235.136.32.0/19235.136.32.1 to 235.136.63.254235.136.63.2558,190
67235.136.64.0/19235.136.64.1 to 235.136.95.254235.136.95.2558,190
68235.136.96.0/19235.136.96.1 to 235.136.127.254235.136.127.2558,190
69235.136.128.0/19235.136.128.1 to 235.136.159.254235.136.159.2558,190
70235.136.160.0/19235.136.160.1 to 235.136.191.254235.136.191.2558,190
71235.136.192.0/19235.136.192.1 to 235.136.223.254235.136.223.2558,190
72235.136.224.0/19235.136.224.1 to 235.136.255.254235.136.255.2558,190
73235.137.0.0/19235.137.0.1 to 235.137.31.254235.137.31.2558,190
74235.137.32.0/19235.137.32.1 to 235.137.63.254235.137.63.2558,190
75235.137.64.0/19235.137.64.1 to 235.137.95.254235.137.95.2558,190
76235.137.96.0/19235.137.96.1 to 235.137.127.254235.137.127.2558,190
77235.137.128.0/19235.137.128.1 to 235.137.159.254235.137.159.2558,190
78235.137.160.0/19235.137.160.1 to 235.137.191.254235.137.191.2558,190
79235.137.192.0/19235.137.192.1 to 235.137.223.254235.137.223.2558,190
80235.137.224.0/19235.137.224.1 to 235.137.255.254235.137.255.2558,190
81235.138.0.0/19235.138.0.1 to 235.138.31.254235.138.31.2558,190
82235.138.32.0/19235.138.32.1 to 235.138.63.254235.138.63.2558,190
83235.138.64.0/19235.138.64.1 to 235.138.95.254235.138.95.2558,190
84235.138.96.0/19235.138.96.1 to 235.138.127.254235.138.127.2558,190
85235.138.128.0/19235.138.128.1 to 235.138.159.254235.138.159.2558,190
86235.138.160.0/19235.138.160.1 to 235.138.191.254235.138.191.2558,190
87235.138.192.0/19235.138.192.1 to 235.138.223.254235.138.223.2558,190
88235.138.224.0/19235.138.224.1 to 235.138.255.254235.138.255.2558,190
89235.139.0.0/19235.139.0.1 to 235.139.31.254235.139.31.2558,190
90235.139.32.0/19235.139.32.1 to 235.139.63.254235.139.63.2558,190
91235.139.64.0/19235.139.64.1 to 235.139.95.254235.139.95.2558,190
92235.139.96.0/19235.139.96.1 to 235.139.127.254235.139.127.2558,190
93235.139.128.0/19235.139.128.1 to 235.139.159.254235.139.159.2558,190
94235.139.160.0/19235.139.160.1 to 235.139.191.254235.139.191.2558,190
95235.139.192.0/19235.139.192.1 to 235.139.223.254235.139.223.2558,190
96235.139.224.0/19235.139.224.1 to 235.139.255.254235.139.255.2558,190
97235.140.0.0/19235.140.0.1 to 235.140.31.254235.140.31.2558,190
98235.140.32.0/19235.140.32.1 to 235.140.63.254235.140.63.2558,190
99235.140.64.0/19235.140.64.1 to 235.140.95.254235.140.95.2558,190
100235.140.96.0/19235.140.96.1 to 235.140.127.254235.140.127.2558,190
101235.140.128.0/19235.140.128.1 to 235.140.159.254235.140.159.2558,190
102235.140.160.0/19235.140.160.1 to 235.140.191.254235.140.191.2558,190
103235.140.192.0/19235.140.192.1 to 235.140.223.254235.140.223.2558,190
104235.140.224.0/19235.140.224.1 to 235.140.255.254235.140.255.2558,190
105235.141.0.0/19235.141.0.1 to 235.141.31.254235.141.31.2558,190
106235.141.32.0/19235.141.32.1 to 235.141.63.254235.141.63.2558,190
107235.141.64.0/19235.141.64.1 to 235.141.95.254235.141.95.2558,190
108235.141.96.0/19235.141.96.1 to 235.141.127.254235.141.127.2558,190
109235.141.128.0/19235.141.128.1 to 235.141.159.254235.141.159.2558,190
110235.141.160.0/19235.141.160.1 to 235.141.191.254235.141.191.2558,190
111235.141.192.0/19235.141.192.1 to 235.141.223.254235.141.223.2558,190
112235.141.224.0/19235.141.224.1 to 235.141.255.254235.141.255.2558,190
113235.142.0.0/19235.142.0.1 to 235.142.31.254235.142.31.2558,190
114235.142.32.0/19235.142.32.1 to 235.142.63.254235.142.63.2558,190
115235.142.64.0/19235.142.64.1 to 235.142.95.254235.142.95.2558,190
116235.142.96.0/19235.142.96.1 to 235.142.127.254235.142.127.2558,190
117235.142.128.0/19235.142.128.1 to 235.142.159.254235.142.159.2558,190
118235.142.160.0/19235.142.160.1 to 235.142.191.254235.142.191.2558,190
119235.142.192.0/19235.142.192.1 to 235.142.223.254235.142.223.2558,190
120235.142.224.0/19235.142.224.1 to 235.142.255.254235.142.255.2558,190
121235.143.0.0/19235.143.0.1 to 235.143.31.254235.143.31.2558,190
122235.143.32.0/19235.143.32.1 to 235.143.63.254235.143.63.2558,190
123235.143.64.0/19235.143.64.1 to 235.143.95.254235.143.95.2558,190
124235.143.96.0/19235.143.96.1 to 235.143.127.254235.143.127.2558,190
125235.143.128.0/19235.143.128.1 to 235.143.159.254235.143.159.2558,190
126235.143.160.0/19235.143.160.1 to 235.143.191.254235.143.191.2558,190
127235.143.192.0/19235.143.192.1 to 235.143.223.254235.143.223.2558,190
128235.143.224.0/19235.143.224.1 to 235.143.255.254235.143.255.2558,190
129235.144.0.0/19235.144.0.1 to 235.144.31.254235.144.31.2558,190
130235.144.32.0/19235.144.32.1 to 235.144.63.254235.144.63.2558,190
131235.144.64.0/19235.144.64.1 to 235.144.95.254235.144.95.2558,190
132235.144.96.0/19235.144.96.1 to 235.144.127.254235.144.127.2558,190
133235.144.128.0/19235.144.128.1 to 235.144.159.254235.144.159.2558,190
134235.144.160.0/19235.144.160.1 to 235.144.191.254235.144.191.2558,190
135235.144.192.0/19235.144.192.1 to 235.144.223.254235.144.223.2558,190
136235.144.224.0/19235.144.224.1 to 235.144.255.254235.144.255.2558,190
137235.145.0.0/19235.145.0.1 to 235.145.31.254235.145.31.2558,190
138235.145.32.0/19235.145.32.1 to 235.145.63.254235.145.63.2558,190
139235.145.64.0/19235.145.64.1 to 235.145.95.254235.145.95.2558,190
140235.145.96.0/19235.145.96.1 to 235.145.127.254235.145.127.2558,190
141235.145.128.0/19235.145.128.1 to 235.145.159.254235.145.159.2558,190
142235.145.160.0/19235.145.160.1 to 235.145.191.254235.145.191.2558,190
143235.145.192.0/19235.145.192.1 to 235.145.223.254235.145.223.2558,190
144235.145.224.0/19235.145.224.1 to 235.145.255.254235.145.255.2558,190
145235.146.0.0/19235.146.0.1 to 235.146.31.254235.146.31.2558,190
146235.146.32.0/19235.146.32.1 to 235.146.63.254235.146.63.2558,190
147235.146.64.0/19235.146.64.1 to 235.146.95.254235.146.95.2558,190
148235.146.96.0/19235.146.96.1 to 235.146.127.254235.146.127.2558,190
149235.146.128.0/19235.146.128.1 to 235.146.159.254235.146.159.2558,190
150235.146.160.0/19235.146.160.1 to 235.146.191.254235.146.191.2558,190
151235.146.192.0/19235.146.192.1 to 235.146.223.254235.146.223.2558,190
152235.146.224.0/19235.146.224.1 to 235.146.255.254235.146.255.2558,190
153235.147.0.0/19235.147.0.1 to 235.147.31.254235.147.31.2558,190
154235.147.32.0/19235.147.32.1 to 235.147.63.254235.147.63.2558,190
155235.147.64.0/19235.147.64.1 to 235.147.95.254235.147.95.2558,190
156235.147.96.0/19235.147.96.1 to 235.147.127.254235.147.127.2558,190
157235.147.128.0/19235.147.128.1 to 235.147.159.254235.147.159.2558,190
158235.147.160.0/19235.147.160.1 to 235.147.191.254235.147.191.2558,190
159235.147.192.0/19235.147.192.1 to 235.147.223.254235.147.223.2558,190
160235.147.224.0/19235.147.224.1 to 235.147.255.254235.147.255.2558,190
161235.148.0.0/19235.148.0.1 to 235.148.31.254235.148.31.2558,190
162235.148.32.0/19235.148.32.1 to 235.148.63.254235.148.63.2558,190
163235.148.64.0/19235.148.64.1 to 235.148.95.254235.148.95.2558,190
164235.148.96.0/19235.148.96.1 to 235.148.127.254235.148.127.2558,190
165235.148.128.0/19235.148.128.1 to 235.148.159.254235.148.159.2558,190
166235.148.160.0/19235.148.160.1 to 235.148.191.254235.148.191.2558,190
167235.148.192.0/19235.148.192.1 to 235.148.223.254235.148.223.2558,190
168235.148.224.0/19235.148.224.1 to 235.148.255.254235.148.255.2558,190
169235.149.0.0/19235.149.0.1 to 235.149.31.254235.149.31.2558,190
170235.149.32.0/19235.149.32.1 to 235.149.63.254235.149.63.2558,190
171235.149.64.0/19235.149.64.1 to 235.149.95.254235.149.95.2558,190
172235.149.96.0/19235.149.96.1 to 235.149.127.254235.149.127.2558,190
173235.149.128.0/19235.149.128.1 to 235.149.159.254235.149.159.2558,190
174235.149.160.0/19235.149.160.1 to 235.149.191.254235.149.191.2558,190
175235.149.192.0/19235.149.192.1 to 235.149.223.254235.149.223.2558,190
176235.149.224.0/19235.149.224.1 to 235.149.255.254235.149.255.2558,190
177235.150.0.0/19235.150.0.1 to 235.150.31.254235.150.31.2558,190
178235.150.32.0/19235.150.32.1 to 235.150.63.254235.150.63.2558,190
179235.150.64.0/19235.150.64.1 to 235.150.95.254235.150.95.2558,190
180235.150.96.0/19235.150.96.1 to 235.150.127.254235.150.127.2558,190
181235.150.128.0/19235.150.128.1 to 235.150.159.254235.150.159.2558,190
182235.150.160.0/19235.150.160.1 to 235.150.191.254235.150.191.2558,190
183235.150.192.0/19235.150.192.1 to 235.150.223.254235.150.223.2558,190
184235.150.224.0/19235.150.224.1 to 235.150.255.254235.150.255.2558,190
185235.151.0.0/19235.151.0.1 to 235.151.31.254235.151.31.2558,190
186235.151.32.0/19235.151.32.1 to 235.151.63.254235.151.63.2558,190
187235.151.64.0/19235.151.64.1 to 235.151.95.254235.151.95.2558,190
188235.151.96.0/19235.151.96.1 to 235.151.127.254235.151.127.2558,190
189235.151.128.0/19235.151.128.1 to 235.151.159.254235.151.159.2558,190
190235.151.160.0/19235.151.160.1 to 235.151.191.254235.151.191.2558,190
191235.151.192.0/19235.151.192.1 to 235.151.223.254235.151.223.2558,190
192235.151.224.0/19235.151.224.1 to 235.151.255.254235.151.255.2558,190
193235.152.0.0/19235.152.0.1 to 235.152.31.254235.152.31.2558,190
194235.152.32.0/19235.152.32.1 to 235.152.63.254235.152.63.2558,190
195235.152.64.0/19235.152.64.1 to 235.152.95.254235.152.95.2558,190
196235.152.96.0/19235.152.96.1 to 235.152.127.254235.152.127.2558,190
197235.152.128.0/19235.152.128.1 to 235.152.159.254235.152.159.2558,190
198235.152.160.0/19235.152.160.1 to 235.152.191.254235.152.191.2558,190
199235.152.192.0/19235.152.192.1 to 235.152.223.254235.152.223.2558,190
200235.152.224.0/19235.152.224.1 to 235.152.255.254235.152.255.2558,190
201235.153.0.0/19235.153.0.1 to 235.153.31.254235.153.31.2558,190
202235.153.32.0/19235.153.32.1 to 235.153.63.254235.153.63.2558,190
203235.153.64.0/19235.153.64.1 to 235.153.95.254235.153.95.2558,190
204235.153.96.0/19235.153.96.1 to 235.153.127.254235.153.127.2558,190
205235.153.128.0/19235.153.128.1 to 235.153.159.254235.153.159.2558,190
206235.153.160.0/19235.153.160.1 to 235.153.191.254235.153.191.2558,190
207235.153.192.0/19235.153.192.1 to 235.153.223.254235.153.223.2558,190
208235.153.224.0/19235.153.224.1 to 235.153.255.254235.153.255.2558,190
209235.154.0.0/19235.154.0.1 to 235.154.31.254235.154.31.2558,190
210235.154.32.0/19235.154.32.1 to 235.154.63.254235.154.63.2558,190
211235.154.64.0/19235.154.64.1 to 235.154.95.254235.154.95.2558,190
212235.154.96.0/19235.154.96.1 to 235.154.127.254235.154.127.2558,190
213235.154.128.0/19235.154.128.1 to 235.154.159.254235.154.159.2558,190
214235.154.160.0/19235.154.160.1 to 235.154.191.254235.154.191.2558,190
215235.154.192.0/19235.154.192.1 to 235.154.223.254235.154.223.2558,190
216235.154.224.0/19235.154.224.1 to 235.154.255.254235.154.255.2558,190
217235.155.0.0/19235.155.0.1 to 235.155.31.254235.155.31.2558,190
218235.155.32.0/19235.155.32.1 to 235.155.63.254235.155.63.2558,190
219235.155.64.0/19235.155.64.1 to 235.155.95.254235.155.95.2558,190
220235.155.96.0/19235.155.96.1 to 235.155.127.254235.155.127.2558,190
221235.155.128.0/19235.155.128.1 to 235.155.159.254235.155.159.2558,190
222235.155.160.0/19235.155.160.1 to 235.155.191.254235.155.191.2558,190
223235.155.192.0/19235.155.192.1 to 235.155.223.254235.155.223.2558,190
224235.155.224.0/19235.155.224.1 to 235.155.255.254235.155.255.2558,190
225235.156.0.0/19235.156.0.1 to 235.156.31.254235.156.31.2558,190
226235.156.32.0/19235.156.32.1 to 235.156.63.254235.156.63.2558,190
227235.156.64.0/19235.156.64.1 to 235.156.95.254235.156.95.2558,190
228235.156.96.0/19235.156.96.1 to 235.156.127.254235.156.127.2558,190
229235.156.128.0/19235.156.128.1 to 235.156.159.254235.156.159.2558,190
230235.156.160.0/19235.156.160.1 to 235.156.191.254235.156.191.2558,190
231235.156.192.0/19235.156.192.1 to 235.156.223.254235.156.223.2558,190
232235.156.224.0/19235.156.224.1 to 235.156.255.254235.156.255.2558,190
233235.157.0.0/19235.157.0.1 to 235.157.31.254235.157.31.2558,190
234235.157.32.0/19235.157.32.1 to 235.157.63.254235.157.63.2558,190
235235.157.64.0/19235.157.64.1 to 235.157.95.254235.157.95.2558,190
236235.157.96.0/19235.157.96.1 to 235.157.127.254235.157.127.2558,190
237235.157.128.0/19235.157.128.1 to 235.157.159.254235.157.159.2558,190
238235.157.160.0/19235.157.160.1 to 235.157.191.254235.157.191.2558,190
239235.157.192.0/19235.157.192.1 to 235.157.223.254235.157.223.2558,190
240235.157.224.0/19235.157.224.1 to 235.157.255.254235.157.255.2558,190
241235.158.0.0/19235.158.0.1 to 235.158.31.254235.158.31.2558,190
242235.158.32.0/19235.158.32.1 to 235.158.63.254235.158.63.2558,190
243235.158.64.0/19235.158.64.1 to 235.158.95.254235.158.95.2558,190
244235.158.96.0/19235.158.96.1 to 235.158.127.254235.158.127.2558,190
245235.158.128.0/19235.158.128.1 to 235.158.159.254235.158.159.2558,190
246235.158.160.0/19235.158.160.1 to 235.158.191.254235.158.191.2558,190
247235.158.192.0/19235.158.192.1 to 235.158.223.254235.158.223.2558,190
248235.158.224.0/19235.158.224.1 to 235.158.255.254235.158.255.2558,190
249235.159.0.0/19235.159.0.1 to 235.159.31.254235.159.31.2558,190
250235.159.32.0/19235.159.32.1 to 235.159.63.254235.159.63.2558,190
251235.159.64.0/19235.159.64.1 to 235.159.95.254235.159.95.2558,190
252235.159.96.0/19235.159.96.1 to 235.159.127.254235.159.127.2558,190
253235.159.128.0/19235.159.128.1 to 235.159.159.254235.159.159.2558,190
254235.159.160.0/19235.159.160.1 to 235.159.191.254235.159.191.2558,190
255235.159.192.0/19235.159.192.1 to 235.159.223.254235.159.223.2558,190
256235.159.224.0/19235.159.224.1 to 235.159.255.254235.159.255.2558,190

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.