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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.

Network154.136.0.0/13
Usable hosts524,286
Subnet mask255.248.0.0
Addresses524,288
Network address
154.136.0.0
Broadcast address
154.143.255.255
First usable
154.136.0.1
Last usable
154.143.255.254
Usable hosts
524,286 (524,288 less the network and broadcast addresses)
Subnet mask
255.248.0.0
Wildcard mask
0.7.255.255 (Cisco ACLs, OSPF)
Prefix length
/13
Type
Public public
Old class
B (default /16)
As numbers
Hex 9A880000 · Integer 2592604160 to 2593128447
Reverse DNS zones
136.154.in-addr.arpa
137.154.in-addr.arpa
138.154.in-addr.arpa
139.154.in-addr.arpa
140.154.in-addr.arpa
141.154.in-addr.arpa
142.154.in-addr.arpa
143.154.in-addr.arpa
/13 is not on a 8-bit boundary, so it takes 8 /16 zones.
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address10011010.10001000.00000000.00000000154.136.0.0
Subnet mask11111111.11111000.00000000.00000000255.248.0.0
Network10011010.10001000.00000000.00000000154.136.0.0
Broadcast10011010.10001111.11111111.11111111154.143.255.255
Split into smaller subnets/21
/14 (2)/15 (4)/16 (8)/17 (16)/18 (32)/19 (64)/20 (128)/21 (256)/22 (512)/23 (1,024)/24 (2,048)/25 (4,096)

154.136.0.0/13 makes 256 subnets of /21.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
1154.136.0.0/21154.136.0.1 to 154.136.7.254154.136.7.2552,046
2154.136.8.0/21154.136.8.1 to 154.136.15.254154.136.15.2552,046
3154.136.16.0/21154.136.16.1 to 154.136.23.254154.136.23.2552,046
4154.136.24.0/21154.136.24.1 to 154.136.31.254154.136.31.2552,046
5154.136.32.0/21154.136.32.1 to 154.136.39.254154.136.39.2552,046
6154.136.40.0/21154.136.40.1 to 154.136.47.254154.136.47.2552,046
7154.136.48.0/21154.136.48.1 to 154.136.55.254154.136.55.2552,046
8154.136.56.0/21154.136.56.1 to 154.136.63.254154.136.63.2552,046
9154.136.64.0/21154.136.64.1 to 154.136.71.254154.136.71.2552,046
10154.136.72.0/21154.136.72.1 to 154.136.79.254154.136.79.2552,046
11154.136.80.0/21154.136.80.1 to 154.136.87.254154.136.87.2552,046
12154.136.88.0/21154.136.88.1 to 154.136.95.254154.136.95.2552,046
13154.136.96.0/21154.136.96.1 to 154.136.103.254154.136.103.2552,046
14154.136.104.0/21154.136.104.1 to 154.136.111.254154.136.111.2552,046
15154.136.112.0/21154.136.112.1 to 154.136.119.254154.136.119.2552,046
16154.136.120.0/21154.136.120.1 to 154.136.127.254154.136.127.2552,046
17154.136.128.0/21154.136.128.1 to 154.136.135.254154.136.135.2552,046
18154.136.136.0/21154.136.136.1 to 154.136.143.254154.136.143.2552,046
19154.136.144.0/21154.136.144.1 to 154.136.151.254154.136.151.2552,046
20154.136.152.0/21154.136.152.1 to 154.136.159.254154.136.159.2552,046
21154.136.160.0/21154.136.160.1 to 154.136.167.254154.136.167.2552,046
22154.136.168.0/21154.136.168.1 to 154.136.175.254154.136.175.2552,046
23154.136.176.0/21154.136.176.1 to 154.136.183.254154.136.183.2552,046
24154.136.184.0/21154.136.184.1 to 154.136.191.254154.136.191.2552,046
25154.136.192.0/21154.136.192.1 to 154.136.199.254154.136.199.2552,046
26154.136.200.0/21154.136.200.1 to 154.136.207.254154.136.207.2552,046
27154.136.208.0/21154.136.208.1 to 154.136.215.254154.136.215.2552,046
28154.136.216.0/21154.136.216.1 to 154.136.223.254154.136.223.2552,046
29154.136.224.0/21154.136.224.1 to 154.136.231.254154.136.231.2552,046
30154.136.232.0/21154.136.232.1 to 154.136.239.254154.136.239.2552,046
31154.136.240.0/21154.136.240.1 to 154.136.247.254154.136.247.2552,046
32154.136.248.0/21154.136.248.1 to 154.136.255.254154.136.255.2552,046
33154.137.0.0/21154.137.0.1 to 154.137.7.254154.137.7.2552,046
34154.137.8.0/21154.137.8.1 to 154.137.15.254154.137.15.2552,046
35154.137.16.0/21154.137.16.1 to 154.137.23.254154.137.23.2552,046
36154.137.24.0/21154.137.24.1 to 154.137.31.254154.137.31.2552,046
37154.137.32.0/21154.137.32.1 to 154.137.39.254154.137.39.2552,046
38154.137.40.0/21154.137.40.1 to 154.137.47.254154.137.47.2552,046
39154.137.48.0/21154.137.48.1 to 154.137.55.254154.137.55.2552,046
40154.137.56.0/21154.137.56.1 to 154.137.63.254154.137.63.2552,046
41154.137.64.0/21154.137.64.1 to 154.137.71.254154.137.71.2552,046
42154.137.72.0/21154.137.72.1 to 154.137.79.254154.137.79.2552,046
43154.137.80.0/21154.137.80.1 to 154.137.87.254154.137.87.2552,046
44154.137.88.0/21154.137.88.1 to 154.137.95.254154.137.95.2552,046
45154.137.96.0/21154.137.96.1 to 154.137.103.254154.137.103.2552,046
46154.137.104.0/21154.137.104.1 to 154.137.111.254154.137.111.2552,046
47154.137.112.0/21154.137.112.1 to 154.137.119.254154.137.119.2552,046
48154.137.120.0/21154.137.120.1 to 154.137.127.254154.137.127.2552,046
49154.137.128.0/21154.137.128.1 to 154.137.135.254154.137.135.2552,046
50154.137.136.0/21154.137.136.1 to 154.137.143.254154.137.143.2552,046
51154.137.144.0/21154.137.144.1 to 154.137.151.254154.137.151.2552,046
52154.137.152.0/21154.137.152.1 to 154.137.159.254154.137.159.2552,046
53154.137.160.0/21154.137.160.1 to 154.137.167.254154.137.167.2552,046
54154.137.168.0/21154.137.168.1 to 154.137.175.254154.137.175.2552,046
55154.137.176.0/21154.137.176.1 to 154.137.183.254154.137.183.2552,046
56154.137.184.0/21154.137.184.1 to 154.137.191.254154.137.191.2552,046
57154.137.192.0/21154.137.192.1 to 154.137.199.254154.137.199.2552,046
58154.137.200.0/21154.137.200.1 to 154.137.207.254154.137.207.2552,046
59154.137.208.0/21154.137.208.1 to 154.137.215.254154.137.215.2552,046
60154.137.216.0/21154.137.216.1 to 154.137.223.254154.137.223.2552,046
61154.137.224.0/21154.137.224.1 to 154.137.231.254154.137.231.2552,046
62154.137.232.0/21154.137.232.1 to 154.137.239.254154.137.239.2552,046
63154.137.240.0/21154.137.240.1 to 154.137.247.254154.137.247.2552,046
64154.137.248.0/21154.137.248.1 to 154.137.255.254154.137.255.2552,046
65154.138.0.0/21154.138.0.1 to 154.138.7.254154.138.7.2552,046
66154.138.8.0/21154.138.8.1 to 154.138.15.254154.138.15.2552,046
67154.138.16.0/21154.138.16.1 to 154.138.23.254154.138.23.2552,046
68154.138.24.0/21154.138.24.1 to 154.138.31.254154.138.31.2552,046
69154.138.32.0/21154.138.32.1 to 154.138.39.254154.138.39.2552,046
70154.138.40.0/21154.138.40.1 to 154.138.47.254154.138.47.2552,046
71154.138.48.0/21154.138.48.1 to 154.138.55.254154.138.55.2552,046
72154.138.56.0/21154.138.56.1 to 154.138.63.254154.138.63.2552,046
73154.138.64.0/21154.138.64.1 to 154.138.71.254154.138.71.2552,046
74154.138.72.0/21154.138.72.1 to 154.138.79.254154.138.79.2552,046
75154.138.80.0/21154.138.80.1 to 154.138.87.254154.138.87.2552,046
76154.138.88.0/21154.138.88.1 to 154.138.95.254154.138.95.2552,046
77154.138.96.0/21154.138.96.1 to 154.138.103.254154.138.103.2552,046
78154.138.104.0/21154.138.104.1 to 154.138.111.254154.138.111.2552,046
79154.138.112.0/21154.138.112.1 to 154.138.119.254154.138.119.2552,046
80154.138.120.0/21154.138.120.1 to 154.138.127.254154.138.127.2552,046
81154.138.128.0/21154.138.128.1 to 154.138.135.254154.138.135.2552,046
82154.138.136.0/21154.138.136.1 to 154.138.143.254154.138.143.2552,046
83154.138.144.0/21154.138.144.1 to 154.138.151.254154.138.151.2552,046
84154.138.152.0/21154.138.152.1 to 154.138.159.254154.138.159.2552,046
85154.138.160.0/21154.138.160.1 to 154.138.167.254154.138.167.2552,046
86154.138.168.0/21154.138.168.1 to 154.138.175.254154.138.175.2552,046
87154.138.176.0/21154.138.176.1 to 154.138.183.254154.138.183.2552,046
88154.138.184.0/21154.138.184.1 to 154.138.191.254154.138.191.2552,046
89154.138.192.0/21154.138.192.1 to 154.138.199.254154.138.199.2552,046
90154.138.200.0/21154.138.200.1 to 154.138.207.254154.138.207.2552,046
91154.138.208.0/21154.138.208.1 to 154.138.215.254154.138.215.2552,046
92154.138.216.0/21154.138.216.1 to 154.138.223.254154.138.223.2552,046
93154.138.224.0/21154.138.224.1 to 154.138.231.254154.138.231.2552,046
94154.138.232.0/21154.138.232.1 to 154.138.239.254154.138.239.2552,046
95154.138.240.0/21154.138.240.1 to 154.138.247.254154.138.247.2552,046
96154.138.248.0/21154.138.248.1 to 154.138.255.254154.138.255.2552,046
97154.139.0.0/21154.139.0.1 to 154.139.7.254154.139.7.2552,046
98154.139.8.0/21154.139.8.1 to 154.139.15.254154.139.15.2552,046
99154.139.16.0/21154.139.16.1 to 154.139.23.254154.139.23.2552,046
100154.139.24.0/21154.139.24.1 to 154.139.31.254154.139.31.2552,046
101154.139.32.0/21154.139.32.1 to 154.139.39.254154.139.39.2552,046
102154.139.40.0/21154.139.40.1 to 154.139.47.254154.139.47.2552,046
103154.139.48.0/21154.139.48.1 to 154.139.55.254154.139.55.2552,046
104154.139.56.0/21154.139.56.1 to 154.139.63.254154.139.63.2552,046
105154.139.64.0/21154.139.64.1 to 154.139.71.254154.139.71.2552,046
106154.139.72.0/21154.139.72.1 to 154.139.79.254154.139.79.2552,046
107154.139.80.0/21154.139.80.1 to 154.139.87.254154.139.87.2552,046
108154.139.88.0/21154.139.88.1 to 154.139.95.254154.139.95.2552,046
109154.139.96.0/21154.139.96.1 to 154.139.103.254154.139.103.2552,046
110154.139.104.0/21154.139.104.1 to 154.139.111.254154.139.111.2552,046
111154.139.112.0/21154.139.112.1 to 154.139.119.254154.139.119.2552,046
112154.139.120.0/21154.139.120.1 to 154.139.127.254154.139.127.2552,046
113154.139.128.0/21154.139.128.1 to 154.139.135.254154.139.135.2552,046
114154.139.136.0/21154.139.136.1 to 154.139.143.254154.139.143.2552,046
115154.139.144.0/21154.139.144.1 to 154.139.151.254154.139.151.2552,046
116154.139.152.0/21154.139.152.1 to 154.139.159.254154.139.159.2552,046
117154.139.160.0/21154.139.160.1 to 154.139.167.254154.139.167.2552,046
118154.139.168.0/21154.139.168.1 to 154.139.175.254154.139.175.2552,046
119154.139.176.0/21154.139.176.1 to 154.139.183.254154.139.183.2552,046
120154.139.184.0/21154.139.184.1 to 154.139.191.254154.139.191.2552,046
121154.139.192.0/21154.139.192.1 to 154.139.199.254154.139.199.2552,046
122154.139.200.0/21154.139.200.1 to 154.139.207.254154.139.207.2552,046
123154.139.208.0/21154.139.208.1 to 154.139.215.254154.139.215.2552,046
124154.139.216.0/21154.139.216.1 to 154.139.223.254154.139.223.2552,046
125154.139.224.0/21154.139.224.1 to 154.139.231.254154.139.231.2552,046
126154.139.232.0/21154.139.232.1 to 154.139.239.254154.139.239.2552,046
127154.139.240.0/21154.139.240.1 to 154.139.247.254154.139.247.2552,046
128154.139.248.0/21154.139.248.1 to 154.139.255.254154.139.255.2552,046
129154.140.0.0/21154.140.0.1 to 154.140.7.254154.140.7.2552,046
130154.140.8.0/21154.140.8.1 to 154.140.15.254154.140.15.2552,046
131154.140.16.0/21154.140.16.1 to 154.140.23.254154.140.23.2552,046
132154.140.24.0/21154.140.24.1 to 154.140.31.254154.140.31.2552,046
133154.140.32.0/21154.140.32.1 to 154.140.39.254154.140.39.2552,046
134154.140.40.0/21154.140.40.1 to 154.140.47.254154.140.47.2552,046
135154.140.48.0/21154.140.48.1 to 154.140.55.254154.140.55.2552,046
136154.140.56.0/21154.140.56.1 to 154.140.63.254154.140.63.2552,046
137154.140.64.0/21154.140.64.1 to 154.140.71.254154.140.71.2552,046
138154.140.72.0/21154.140.72.1 to 154.140.79.254154.140.79.2552,046
139154.140.80.0/21154.140.80.1 to 154.140.87.254154.140.87.2552,046
140154.140.88.0/21154.140.88.1 to 154.140.95.254154.140.95.2552,046
141154.140.96.0/21154.140.96.1 to 154.140.103.254154.140.103.2552,046
142154.140.104.0/21154.140.104.1 to 154.140.111.254154.140.111.2552,046
143154.140.112.0/21154.140.112.1 to 154.140.119.254154.140.119.2552,046
144154.140.120.0/21154.140.120.1 to 154.140.127.254154.140.127.2552,046
145154.140.128.0/21154.140.128.1 to 154.140.135.254154.140.135.2552,046
146154.140.136.0/21154.140.136.1 to 154.140.143.254154.140.143.2552,046
147154.140.144.0/21154.140.144.1 to 154.140.151.254154.140.151.2552,046
148154.140.152.0/21154.140.152.1 to 154.140.159.254154.140.159.2552,046
149154.140.160.0/21154.140.160.1 to 154.140.167.254154.140.167.2552,046
150154.140.168.0/21154.140.168.1 to 154.140.175.254154.140.175.2552,046
151154.140.176.0/21154.140.176.1 to 154.140.183.254154.140.183.2552,046
152154.140.184.0/21154.140.184.1 to 154.140.191.254154.140.191.2552,046
153154.140.192.0/21154.140.192.1 to 154.140.199.254154.140.199.2552,046
154154.140.200.0/21154.140.200.1 to 154.140.207.254154.140.207.2552,046
155154.140.208.0/21154.140.208.1 to 154.140.215.254154.140.215.2552,046
156154.140.216.0/21154.140.216.1 to 154.140.223.254154.140.223.2552,046
157154.140.224.0/21154.140.224.1 to 154.140.231.254154.140.231.2552,046
158154.140.232.0/21154.140.232.1 to 154.140.239.254154.140.239.2552,046
159154.140.240.0/21154.140.240.1 to 154.140.247.254154.140.247.2552,046
160154.140.248.0/21154.140.248.1 to 154.140.255.254154.140.255.2552,046
161154.141.0.0/21154.141.0.1 to 154.141.7.254154.141.7.2552,046
162154.141.8.0/21154.141.8.1 to 154.141.15.254154.141.15.2552,046
163154.141.16.0/21154.141.16.1 to 154.141.23.254154.141.23.2552,046
164154.141.24.0/21154.141.24.1 to 154.141.31.254154.141.31.2552,046
165154.141.32.0/21154.141.32.1 to 154.141.39.254154.141.39.2552,046
166154.141.40.0/21154.141.40.1 to 154.141.47.254154.141.47.2552,046
167154.141.48.0/21154.141.48.1 to 154.141.55.254154.141.55.2552,046
168154.141.56.0/21154.141.56.1 to 154.141.63.254154.141.63.2552,046
169154.141.64.0/21154.141.64.1 to 154.141.71.254154.141.71.2552,046
170154.141.72.0/21154.141.72.1 to 154.141.79.254154.141.79.2552,046
171154.141.80.0/21154.141.80.1 to 154.141.87.254154.141.87.2552,046
172154.141.88.0/21154.141.88.1 to 154.141.95.254154.141.95.2552,046
173154.141.96.0/21154.141.96.1 to 154.141.103.254154.141.103.2552,046
174154.141.104.0/21154.141.104.1 to 154.141.111.254154.141.111.2552,046
175154.141.112.0/21154.141.112.1 to 154.141.119.254154.141.119.2552,046
176154.141.120.0/21154.141.120.1 to 154.141.127.254154.141.127.2552,046
177154.141.128.0/21154.141.128.1 to 154.141.135.254154.141.135.2552,046
178154.141.136.0/21154.141.136.1 to 154.141.143.254154.141.143.2552,046
179154.141.144.0/21154.141.144.1 to 154.141.151.254154.141.151.2552,046
180154.141.152.0/21154.141.152.1 to 154.141.159.254154.141.159.2552,046
181154.141.160.0/21154.141.160.1 to 154.141.167.254154.141.167.2552,046
182154.141.168.0/21154.141.168.1 to 154.141.175.254154.141.175.2552,046
183154.141.176.0/21154.141.176.1 to 154.141.183.254154.141.183.2552,046
184154.141.184.0/21154.141.184.1 to 154.141.191.254154.141.191.2552,046
185154.141.192.0/21154.141.192.1 to 154.141.199.254154.141.199.2552,046
186154.141.200.0/21154.141.200.1 to 154.141.207.254154.141.207.2552,046
187154.141.208.0/21154.141.208.1 to 154.141.215.254154.141.215.2552,046
188154.141.216.0/21154.141.216.1 to 154.141.223.254154.141.223.2552,046
189154.141.224.0/21154.141.224.1 to 154.141.231.254154.141.231.2552,046
190154.141.232.0/21154.141.232.1 to 154.141.239.254154.141.239.2552,046
191154.141.240.0/21154.141.240.1 to 154.141.247.254154.141.247.2552,046
192154.141.248.0/21154.141.248.1 to 154.141.255.254154.141.255.2552,046
193154.142.0.0/21154.142.0.1 to 154.142.7.254154.142.7.2552,046
194154.142.8.0/21154.142.8.1 to 154.142.15.254154.142.15.2552,046
195154.142.16.0/21154.142.16.1 to 154.142.23.254154.142.23.2552,046
196154.142.24.0/21154.142.24.1 to 154.142.31.254154.142.31.2552,046
197154.142.32.0/21154.142.32.1 to 154.142.39.254154.142.39.2552,046
198154.142.40.0/21154.142.40.1 to 154.142.47.254154.142.47.2552,046
199154.142.48.0/21154.142.48.1 to 154.142.55.254154.142.55.2552,046
200154.142.56.0/21154.142.56.1 to 154.142.63.254154.142.63.2552,046
201154.142.64.0/21154.142.64.1 to 154.142.71.254154.142.71.2552,046
202154.142.72.0/21154.142.72.1 to 154.142.79.254154.142.79.2552,046
203154.142.80.0/21154.142.80.1 to 154.142.87.254154.142.87.2552,046
204154.142.88.0/21154.142.88.1 to 154.142.95.254154.142.95.2552,046
205154.142.96.0/21154.142.96.1 to 154.142.103.254154.142.103.2552,046
206154.142.104.0/21154.142.104.1 to 154.142.111.254154.142.111.2552,046
207154.142.112.0/21154.142.112.1 to 154.142.119.254154.142.119.2552,046
208154.142.120.0/21154.142.120.1 to 154.142.127.254154.142.127.2552,046
209154.142.128.0/21154.142.128.1 to 154.142.135.254154.142.135.2552,046
210154.142.136.0/21154.142.136.1 to 154.142.143.254154.142.143.2552,046
211154.142.144.0/21154.142.144.1 to 154.142.151.254154.142.151.2552,046
212154.142.152.0/21154.142.152.1 to 154.142.159.254154.142.159.2552,046
213154.142.160.0/21154.142.160.1 to 154.142.167.254154.142.167.2552,046
214154.142.168.0/21154.142.168.1 to 154.142.175.254154.142.175.2552,046
215154.142.176.0/21154.142.176.1 to 154.142.183.254154.142.183.2552,046
216154.142.184.0/21154.142.184.1 to 154.142.191.254154.142.191.2552,046
217154.142.192.0/21154.142.192.1 to 154.142.199.254154.142.199.2552,046
218154.142.200.0/21154.142.200.1 to 154.142.207.254154.142.207.2552,046
219154.142.208.0/21154.142.208.1 to 154.142.215.254154.142.215.2552,046
220154.142.216.0/21154.142.216.1 to 154.142.223.254154.142.223.2552,046
221154.142.224.0/21154.142.224.1 to 154.142.231.254154.142.231.2552,046
222154.142.232.0/21154.142.232.1 to 154.142.239.254154.142.239.2552,046
223154.142.240.0/21154.142.240.1 to 154.142.247.254154.142.247.2552,046
224154.142.248.0/21154.142.248.1 to 154.142.255.254154.142.255.2552,046
225154.143.0.0/21154.143.0.1 to 154.143.7.254154.143.7.2552,046
226154.143.8.0/21154.143.8.1 to 154.143.15.254154.143.15.2552,046
227154.143.16.0/21154.143.16.1 to 154.143.23.254154.143.23.2552,046
228154.143.24.0/21154.143.24.1 to 154.143.31.254154.143.31.2552,046
229154.143.32.0/21154.143.32.1 to 154.143.39.254154.143.39.2552,046
230154.143.40.0/21154.143.40.1 to 154.143.47.254154.143.47.2552,046
231154.143.48.0/21154.143.48.1 to 154.143.55.254154.143.55.2552,046
232154.143.56.0/21154.143.56.1 to 154.143.63.254154.143.63.2552,046
233154.143.64.0/21154.143.64.1 to 154.143.71.254154.143.71.2552,046
234154.143.72.0/21154.143.72.1 to 154.143.79.254154.143.79.2552,046
235154.143.80.0/21154.143.80.1 to 154.143.87.254154.143.87.2552,046
236154.143.88.0/21154.143.88.1 to 154.143.95.254154.143.95.2552,046
237154.143.96.0/21154.143.96.1 to 154.143.103.254154.143.103.2552,046
238154.143.104.0/21154.143.104.1 to 154.143.111.254154.143.111.2552,046
239154.143.112.0/21154.143.112.1 to 154.143.119.254154.143.119.2552,046
240154.143.120.0/21154.143.120.1 to 154.143.127.254154.143.127.2552,046
241154.143.128.0/21154.143.128.1 to 154.143.135.254154.143.135.2552,046
242154.143.136.0/21154.143.136.1 to 154.143.143.254154.143.143.2552,046
243154.143.144.0/21154.143.144.1 to 154.143.151.254154.143.151.2552,046
244154.143.152.0/21154.143.152.1 to 154.143.159.254154.143.159.2552,046
245154.143.160.0/21154.143.160.1 to 154.143.167.254154.143.167.2552,046
246154.143.168.0/21154.143.168.1 to 154.143.175.254154.143.175.2552,046
247154.143.176.0/21154.143.176.1 to 154.143.183.254154.143.183.2552,046
248154.143.184.0/21154.143.184.1 to 154.143.191.254154.143.191.2552,046
249154.143.192.0/21154.143.192.1 to 154.143.199.254154.143.199.2552,046
250154.143.200.0/21154.143.200.1 to 154.143.207.254154.143.207.2552,046
251154.143.208.0/21154.143.208.1 to 154.143.215.254154.143.215.2552,046
252154.143.216.0/21154.143.216.1 to 154.143.223.254154.143.223.2552,046
253154.143.224.0/21154.143.224.1 to 154.143.231.254154.143.231.2552,046
254154.143.232.0/21154.143.232.1 to 154.143.239.254154.143.239.2552,046
255154.143.240.0/21154.143.240.1 to 154.143.247.254154.143.247.2552,046
256154.143.248.0/21154.143.248.1 to 154.143.255.254154.143.255.2552,046

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.