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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.

Network152.0.0.0/5
Usable hosts134,217,726
Subnet mask248.0.0.0
Addresses134,217,728
Network address
152.0.0.0
Broadcast address
159.255.255.255
First usable
152.0.0.1
Last usable
159.255.255.254
Usable hosts
134,217,726 (134,217,728 less the network and broadcast addresses)
Subnet mask
248.0.0.0
Wildcard mask
7.255.255.255 (Cisco ACLs, OSPF)
Prefix length
/5
Type
Public public
Old class
B (default /16)
As numbers
Hex 98000000 · Integer 2550136832 to 2684354559
Reverse DNS zones
152.in-addr.arpa
153.in-addr.arpa
154.in-addr.arpa
155.in-addr.arpa
156.in-addr.arpa
157.in-addr.arpa
158.in-addr.arpa
159.in-addr.arpa
/5 is not on a 8-bit boundary, so it takes 8 /8 zones.
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address10011000.00000000.00000000.00000000152.0.0.0
Subnet mask11111000.00000000.00000000.00000000248.0.0.0
Network10011000.00000000.00000000.00000000152.0.0.0
Broadcast10011111.11111111.11111111.11111111159.255.255.255
Split into smaller subnets/14
/6 (2)/7 (4)/8 (8)/9 (16)/10 (32)/11 (64)/12 (128)/13 (256)/14 (512)/15 (1,024)/16 (2,048)/17 (4,096)

152.0.0.0/5 makes 512 subnets of /14; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
1152.0.0.0/14152.0.0.1 to 152.3.255.254152.3.255.255262,142
2152.4.0.0/14152.4.0.1 to 152.7.255.254152.7.255.255262,142
3152.8.0.0/14152.8.0.1 to 152.11.255.254152.11.255.255262,142
4152.12.0.0/14152.12.0.1 to 152.15.255.254152.15.255.255262,142
5152.16.0.0/14152.16.0.1 to 152.19.255.254152.19.255.255262,142
6152.20.0.0/14152.20.0.1 to 152.23.255.254152.23.255.255262,142
7152.24.0.0/14152.24.0.1 to 152.27.255.254152.27.255.255262,142
8152.28.0.0/14152.28.0.1 to 152.31.255.254152.31.255.255262,142
9152.32.0.0/14152.32.0.1 to 152.35.255.254152.35.255.255262,142
10152.36.0.0/14152.36.0.1 to 152.39.255.254152.39.255.255262,142
11152.40.0.0/14152.40.0.1 to 152.43.255.254152.43.255.255262,142
12152.44.0.0/14152.44.0.1 to 152.47.255.254152.47.255.255262,142
13152.48.0.0/14152.48.0.1 to 152.51.255.254152.51.255.255262,142
14152.52.0.0/14152.52.0.1 to 152.55.255.254152.55.255.255262,142
15152.56.0.0/14152.56.0.1 to 152.59.255.254152.59.255.255262,142
16152.60.0.0/14152.60.0.1 to 152.63.255.254152.63.255.255262,142
17152.64.0.0/14152.64.0.1 to 152.67.255.254152.67.255.255262,142
18152.68.0.0/14152.68.0.1 to 152.71.255.254152.71.255.255262,142
19152.72.0.0/14152.72.0.1 to 152.75.255.254152.75.255.255262,142
20152.76.0.0/14152.76.0.1 to 152.79.255.254152.79.255.255262,142
21152.80.0.0/14152.80.0.1 to 152.83.255.254152.83.255.255262,142
22152.84.0.0/14152.84.0.1 to 152.87.255.254152.87.255.255262,142
23152.88.0.0/14152.88.0.1 to 152.91.255.254152.91.255.255262,142
24152.92.0.0/14152.92.0.1 to 152.95.255.254152.95.255.255262,142
25152.96.0.0/14152.96.0.1 to 152.99.255.254152.99.255.255262,142
26152.100.0.0/14152.100.0.1 to 152.103.255.254152.103.255.255262,142
27152.104.0.0/14152.104.0.1 to 152.107.255.254152.107.255.255262,142
28152.108.0.0/14152.108.0.1 to 152.111.255.254152.111.255.255262,142
29152.112.0.0/14152.112.0.1 to 152.115.255.254152.115.255.255262,142
30152.116.0.0/14152.116.0.1 to 152.119.255.254152.119.255.255262,142
31152.120.0.0/14152.120.0.1 to 152.123.255.254152.123.255.255262,142
32152.124.0.0/14152.124.0.1 to 152.127.255.254152.127.255.255262,142
33152.128.0.0/14152.128.0.1 to 152.131.255.254152.131.255.255262,142
34152.132.0.0/14152.132.0.1 to 152.135.255.254152.135.255.255262,142
35152.136.0.0/14152.136.0.1 to 152.139.255.254152.139.255.255262,142
36152.140.0.0/14152.140.0.1 to 152.143.255.254152.143.255.255262,142
37152.144.0.0/14152.144.0.1 to 152.147.255.254152.147.255.255262,142
38152.148.0.0/14152.148.0.1 to 152.151.255.254152.151.255.255262,142
39152.152.0.0/14152.152.0.1 to 152.155.255.254152.155.255.255262,142
40152.156.0.0/14152.156.0.1 to 152.159.255.254152.159.255.255262,142
41152.160.0.0/14152.160.0.1 to 152.163.255.254152.163.255.255262,142
42152.164.0.0/14152.164.0.1 to 152.167.255.254152.167.255.255262,142
43152.168.0.0/14152.168.0.1 to 152.171.255.254152.171.255.255262,142
44152.172.0.0/14152.172.0.1 to 152.175.255.254152.175.255.255262,142
45152.176.0.0/14152.176.0.1 to 152.179.255.254152.179.255.255262,142
46152.180.0.0/14152.180.0.1 to 152.183.255.254152.183.255.255262,142
47152.184.0.0/14152.184.0.1 to 152.187.255.254152.187.255.255262,142
48152.188.0.0/14152.188.0.1 to 152.191.255.254152.191.255.255262,142
49152.192.0.0/14152.192.0.1 to 152.195.255.254152.195.255.255262,142
50152.196.0.0/14152.196.0.1 to 152.199.255.254152.199.255.255262,142
51152.200.0.0/14152.200.0.1 to 152.203.255.254152.203.255.255262,142
52152.204.0.0/14152.204.0.1 to 152.207.255.254152.207.255.255262,142
53152.208.0.0/14152.208.0.1 to 152.211.255.254152.211.255.255262,142
54152.212.0.0/14152.212.0.1 to 152.215.255.254152.215.255.255262,142
55152.216.0.0/14152.216.0.1 to 152.219.255.254152.219.255.255262,142
56152.220.0.0/14152.220.0.1 to 152.223.255.254152.223.255.255262,142
57152.224.0.0/14152.224.0.1 to 152.227.255.254152.227.255.255262,142
58152.228.0.0/14152.228.0.1 to 152.231.255.254152.231.255.255262,142
59152.232.0.0/14152.232.0.1 to 152.235.255.254152.235.255.255262,142
60152.236.0.0/14152.236.0.1 to 152.239.255.254152.239.255.255262,142
61152.240.0.0/14152.240.0.1 to 152.243.255.254152.243.255.255262,142
62152.244.0.0/14152.244.0.1 to 152.247.255.254152.247.255.255262,142
63152.248.0.0/14152.248.0.1 to 152.251.255.254152.251.255.255262,142
64152.252.0.0/14152.252.0.1 to 152.255.255.254152.255.255.255262,142
65153.0.0.0/14153.0.0.1 to 153.3.255.254153.3.255.255262,142
66153.4.0.0/14153.4.0.1 to 153.7.255.254153.7.255.255262,142
67153.8.0.0/14153.8.0.1 to 153.11.255.254153.11.255.255262,142
68153.12.0.0/14153.12.0.1 to 153.15.255.254153.15.255.255262,142
69153.16.0.0/14153.16.0.1 to 153.19.255.254153.19.255.255262,142
70153.20.0.0/14153.20.0.1 to 153.23.255.254153.23.255.255262,142
71153.24.0.0/14153.24.0.1 to 153.27.255.254153.27.255.255262,142
72153.28.0.0/14153.28.0.1 to 153.31.255.254153.31.255.255262,142
73153.32.0.0/14153.32.0.1 to 153.35.255.254153.35.255.255262,142
74153.36.0.0/14153.36.0.1 to 153.39.255.254153.39.255.255262,142
75153.40.0.0/14153.40.0.1 to 153.43.255.254153.43.255.255262,142
76153.44.0.0/14153.44.0.1 to 153.47.255.254153.47.255.255262,142
77153.48.0.0/14153.48.0.1 to 153.51.255.254153.51.255.255262,142
78153.52.0.0/14153.52.0.1 to 153.55.255.254153.55.255.255262,142
79153.56.0.0/14153.56.0.1 to 153.59.255.254153.59.255.255262,142
80153.60.0.0/14153.60.0.1 to 153.63.255.254153.63.255.255262,142
81153.64.0.0/14153.64.0.1 to 153.67.255.254153.67.255.255262,142
82153.68.0.0/14153.68.0.1 to 153.71.255.254153.71.255.255262,142
83153.72.0.0/14153.72.0.1 to 153.75.255.254153.75.255.255262,142
84153.76.0.0/14153.76.0.1 to 153.79.255.254153.79.255.255262,142
85153.80.0.0/14153.80.0.1 to 153.83.255.254153.83.255.255262,142
86153.84.0.0/14153.84.0.1 to 153.87.255.254153.87.255.255262,142
87153.88.0.0/14153.88.0.1 to 153.91.255.254153.91.255.255262,142
88153.92.0.0/14153.92.0.1 to 153.95.255.254153.95.255.255262,142
89153.96.0.0/14153.96.0.1 to 153.99.255.254153.99.255.255262,142
90153.100.0.0/14153.100.0.1 to 153.103.255.254153.103.255.255262,142
91153.104.0.0/14153.104.0.1 to 153.107.255.254153.107.255.255262,142
92153.108.0.0/14153.108.0.1 to 153.111.255.254153.111.255.255262,142
93153.112.0.0/14153.112.0.1 to 153.115.255.254153.115.255.255262,142
94153.116.0.0/14153.116.0.1 to 153.119.255.254153.119.255.255262,142
95153.120.0.0/14153.120.0.1 to 153.123.255.254153.123.255.255262,142
96153.124.0.0/14153.124.0.1 to 153.127.255.254153.127.255.255262,142
97153.128.0.0/14153.128.0.1 to 153.131.255.254153.131.255.255262,142
98153.132.0.0/14153.132.0.1 to 153.135.255.254153.135.255.255262,142
99153.136.0.0/14153.136.0.1 to 153.139.255.254153.139.255.255262,142
100153.140.0.0/14153.140.0.1 to 153.143.255.254153.143.255.255262,142
101153.144.0.0/14153.144.0.1 to 153.147.255.254153.147.255.255262,142
102153.148.0.0/14153.148.0.1 to 153.151.255.254153.151.255.255262,142
103153.152.0.0/14153.152.0.1 to 153.155.255.254153.155.255.255262,142
104153.156.0.0/14153.156.0.1 to 153.159.255.254153.159.255.255262,142
105153.160.0.0/14153.160.0.1 to 153.163.255.254153.163.255.255262,142
106153.164.0.0/14153.164.0.1 to 153.167.255.254153.167.255.255262,142
107153.168.0.0/14153.168.0.1 to 153.171.255.254153.171.255.255262,142
108153.172.0.0/14153.172.0.1 to 153.175.255.254153.175.255.255262,142
109153.176.0.0/14153.176.0.1 to 153.179.255.254153.179.255.255262,142
110153.180.0.0/14153.180.0.1 to 153.183.255.254153.183.255.255262,142
111153.184.0.0/14153.184.0.1 to 153.187.255.254153.187.255.255262,142
112153.188.0.0/14153.188.0.1 to 153.191.255.254153.191.255.255262,142
113153.192.0.0/14153.192.0.1 to 153.195.255.254153.195.255.255262,142
114153.196.0.0/14153.196.0.1 to 153.199.255.254153.199.255.255262,142
115153.200.0.0/14153.200.0.1 to 153.203.255.254153.203.255.255262,142
116153.204.0.0/14153.204.0.1 to 153.207.255.254153.207.255.255262,142
117153.208.0.0/14153.208.0.1 to 153.211.255.254153.211.255.255262,142
118153.212.0.0/14153.212.0.1 to 153.215.255.254153.215.255.255262,142
119153.216.0.0/14153.216.0.1 to 153.219.255.254153.219.255.255262,142
120153.220.0.0/14153.220.0.1 to 153.223.255.254153.223.255.255262,142
121153.224.0.0/14153.224.0.1 to 153.227.255.254153.227.255.255262,142
122153.228.0.0/14153.228.0.1 to 153.231.255.254153.231.255.255262,142
123153.232.0.0/14153.232.0.1 to 153.235.255.254153.235.255.255262,142
124153.236.0.0/14153.236.0.1 to 153.239.255.254153.239.255.255262,142
125153.240.0.0/14153.240.0.1 to 153.243.255.254153.243.255.255262,142
126153.244.0.0/14153.244.0.1 to 153.247.255.254153.247.255.255262,142
127153.248.0.0/14153.248.0.1 to 153.251.255.254153.251.255.255262,142
128153.252.0.0/14153.252.0.1 to 153.255.255.254153.255.255.255262,142
129154.0.0.0/14154.0.0.1 to 154.3.255.254154.3.255.255262,142
130154.4.0.0/14154.4.0.1 to 154.7.255.254154.7.255.255262,142
131154.8.0.0/14154.8.0.1 to 154.11.255.254154.11.255.255262,142
132154.12.0.0/14154.12.0.1 to 154.15.255.254154.15.255.255262,142
133154.16.0.0/14154.16.0.1 to 154.19.255.254154.19.255.255262,142
134154.20.0.0/14154.20.0.1 to 154.23.255.254154.23.255.255262,142
135154.24.0.0/14154.24.0.1 to 154.27.255.254154.27.255.255262,142
136154.28.0.0/14154.28.0.1 to 154.31.255.254154.31.255.255262,142
137154.32.0.0/14154.32.0.1 to 154.35.255.254154.35.255.255262,142
138154.36.0.0/14154.36.0.1 to 154.39.255.254154.39.255.255262,142
139154.40.0.0/14154.40.0.1 to 154.43.255.254154.43.255.255262,142
140154.44.0.0/14154.44.0.1 to 154.47.255.254154.47.255.255262,142
141154.48.0.0/14154.48.0.1 to 154.51.255.254154.51.255.255262,142
142154.52.0.0/14154.52.0.1 to 154.55.255.254154.55.255.255262,142
143154.56.0.0/14154.56.0.1 to 154.59.255.254154.59.255.255262,142
144154.60.0.0/14154.60.0.1 to 154.63.255.254154.63.255.255262,142
145154.64.0.0/14154.64.0.1 to 154.67.255.254154.67.255.255262,142
146154.68.0.0/14154.68.0.1 to 154.71.255.254154.71.255.255262,142
147154.72.0.0/14154.72.0.1 to 154.75.255.254154.75.255.255262,142
148154.76.0.0/14154.76.0.1 to 154.79.255.254154.79.255.255262,142
149154.80.0.0/14154.80.0.1 to 154.83.255.254154.83.255.255262,142
150154.84.0.0/14154.84.0.1 to 154.87.255.254154.87.255.255262,142
151154.88.0.0/14154.88.0.1 to 154.91.255.254154.91.255.255262,142
152154.92.0.0/14154.92.0.1 to 154.95.255.254154.95.255.255262,142
153154.96.0.0/14154.96.0.1 to 154.99.255.254154.99.255.255262,142
154154.100.0.0/14154.100.0.1 to 154.103.255.254154.103.255.255262,142
155154.104.0.0/14154.104.0.1 to 154.107.255.254154.107.255.255262,142
156154.108.0.0/14154.108.0.1 to 154.111.255.254154.111.255.255262,142
157154.112.0.0/14154.112.0.1 to 154.115.255.254154.115.255.255262,142
158154.116.0.0/14154.116.0.1 to 154.119.255.254154.119.255.255262,142
159154.120.0.0/14154.120.0.1 to 154.123.255.254154.123.255.255262,142
160154.124.0.0/14154.124.0.1 to 154.127.255.254154.127.255.255262,142
161154.128.0.0/14154.128.0.1 to 154.131.255.254154.131.255.255262,142
162154.132.0.0/14154.132.0.1 to 154.135.255.254154.135.255.255262,142
163154.136.0.0/14154.136.0.1 to 154.139.255.254154.139.255.255262,142
164154.140.0.0/14154.140.0.1 to 154.143.255.254154.143.255.255262,142
165154.144.0.0/14154.144.0.1 to 154.147.255.254154.147.255.255262,142
166154.148.0.0/14154.148.0.1 to 154.151.255.254154.151.255.255262,142
167154.152.0.0/14154.152.0.1 to 154.155.255.254154.155.255.255262,142
168154.156.0.0/14154.156.0.1 to 154.159.255.254154.159.255.255262,142
169154.160.0.0/14154.160.0.1 to 154.163.255.254154.163.255.255262,142
170154.164.0.0/14154.164.0.1 to 154.167.255.254154.167.255.255262,142
171154.168.0.0/14154.168.0.1 to 154.171.255.254154.171.255.255262,142
172154.172.0.0/14154.172.0.1 to 154.175.255.254154.175.255.255262,142
173154.176.0.0/14154.176.0.1 to 154.179.255.254154.179.255.255262,142
174154.180.0.0/14154.180.0.1 to 154.183.255.254154.183.255.255262,142
175154.184.0.0/14154.184.0.1 to 154.187.255.254154.187.255.255262,142
176154.188.0.0/14154.188.0.1 to 154.191.255.254154.191.255.255262,142
177154.192.0.0/14154.192.0.1 to 154.195.255.254154.195.255.255262,142
178154.196.0.0/14154.196.0.1 to 154.199.255.254154.199.255.255262,142
179154.200.0.0/14154.200.0.1 to 154.203.255.254154.203.255.255262,142
180154.204.0.0/14154.204.0.1 to 154.207.255.254154.207.255.255262,142
181154.208.0.0/14154.208.0.1 to 154.211.255.254154.211.255.255262,142
182154.212.0.0/14154.212.0.1 to 154.215.255.254154.215.255.255262,142
183154.216.0.0/14154.216.0.1 to 154.219.255.254154.219.255.255262,142
184154.220.0.0/14154.220.0.1 to 154.223.255.254154.223.255.255262,142
185154.224.0.0/14154.224.0.1 to 154.227.255.254154.227.255.255262,142
186154.228.0.0/14154.228.0.1 to 154.231.255.254154.231.255.255262,142
187154.232.0.0/14154.232.0.1 to 154.235.255.254154.235.255.255262,142
188154.236.0.0/14154.236.0.1 to 154.239.255.254154.239.255.255262,142
189154.240.0.0/14154.240.0.1 to 154.243.255.254154.243.255.255262,142
190154.244.0.0/14154.244.0.1 to 154.247.255.254154.247.255.255262,142
191154.248.0.0/14154.248.0.1 to 154.251.255.254154.251.255.255262,142
192154.252.0.0/14154.252.0.1 to 154.255.255.254154.255.255.255262,142
193155.0.0.0/14155.0.0.1 to 155.3.255.254155.3.255.255262,142
194155.4.0.0/14155.4.0.1 to 155.7.255.254155.7.255.255262,142
195155.8.0.0/14155.8.0.1 to 155.11.255.254155.11.255.255262,142
196155.12.0.0/14155.12.0.1 to 155.15.255.254155.15.255.255262,142
197155.16.0.0/14155.16.0.1 to 155.19.255.254155.19.255.255262,142
198155.20.0.0/14155.20.0.1 to 155.23.255.254155.23.255.255262,142
199155.24.0.0/14155.24.0.1 to 155.27.255.254155.27.255.255262,142
200155.28.0.0/14155.28.0.1 to 155.31.255.254155.31.255.255262,142
201155.32.0.0/14155.32.0.1 to 155.35.255.254155.35.255.255262,142
202155.36.0.0/14155.36.0.1 to 155.39.255.254155.39.255.255262,142
203155.40.0.0/14155.40.0.1 to 155.43.255.254155.43.255.255262,142
204155.44.0.0/14155.44.0.1 to 155.47.255.254155.47.255.255262,142
205155.48.0.0/14155.48.0.1 to 155.51.255.254155.51.255.255262,142
206155.52.0.0/14155.52.0.1 to 155.55.255.254155.55.255.255262,142
207155.56.0.0/14155.56.0.1 to 155.59.255.254155.59.255.255262,142
208155.60.0.0/14155.60.0.1 to 155.63.255.254155.63.255.255262,142
209155.64.0.0/14155.64.0.1 to 155.67.255.254155.67.255.255262,142
210155.68.0.0/14155.68.0.1 to 155.71.255.254155.71.255.255262,142
211155.72.0.0/14155.72.0.1 to 155.75.255.254155.75.255.255262,142
212155.76.0.0/14155.76.0.1 to 155.79.255.254155.79.255.255262,142
213155.80.0.0/14155.80.0.1 to 155.83.255.254155.83.255.255262,142
214155.84.0.0/14155.84.0.1 to 155.87.255.254155.87.255.255262,142
215155.88.0.0/14155.88.0.1 to 155.91.255.254155.91.255.255262,142
216155.92.0.0/14155.92.0.1 to 155.95.255.254155.95.255.255262,142
217155.96.0.0/14155.96.0.1 to 155.99.255.254155.99.255.255262,142
218155.100.0.0/14155.100.0.1 to 155.103.255.254155.103.255.255262,142
219155.104.0.0/14155.104.0.1 to 155.107.255.254155.107.255.255262,142
220155.108.0.0/14155.108.0.1 to 155.111.255.254155.111.255.255262,142
221155.112.0.0/14155.112.0.1 to 155.115.255.254155.115.255.255262,142
222155.116.0.0/14155.116.0.1 to 155.119.255.254155.119.255.255262,142
223155.120.0.0/14155.120.0.1 to 155.123.255.254155.123.255.255262,142
224155.124.0.0/14155.124.0.1 to 155.127.255.254155.127.255.255262,142
225155.128.0.0/14155.128.0.1 to 155.131.255.254155.131.255.255262,142
226155.132.0.0/14155.132.0.1 to 155.135.255.254155.135.255.255262,142
227155.136.0.0/14155.136.0.1 to 155.139.255.254155.139.255.255262,142
228155.140.0.0/14155.140.0.1 to 155.143.255.254155.143.255.255262,142
229155.144.0.0/14155.144.0.1 to 155.147.255.254155.147.255.255262,142
230155.148.0.0/14155.148.0.1 to 155.151.255.254155.151.255.255262,142
231155.152.0.0/14155.152.0.1 to 155.155.255.254155.155.255.255262,142
232155.156.0.0/14155.156.0.1 to 155.159.255.254155.159.255.255262,142
233155.160.0.0/14155.160.0.1 to 155.163.255.254155.163.255.255262,142
234155.164.0.0/14155.164.0.1 to 155.167.255.254155.167.255.255262,142
235155.168.0.0/14155.168.0.1 to 155.171.255.254155.171.255.255262,142
236155.172.0.0/14155.172.0.1 to 155.175.255.254155.175.255.255262,142
237155.176.0.0/14155.176.0.1 to 155.179.255.254155.179.255.255262,142
238155.180.0.0/14155.180.0.1 to 155.183.255.254155.183.255.255262,142
239155.184.0.0/14155.184.0.1 to 155.187.255.254155.187.255.255262,142
240155.188.0.0/14155.188.0.1 to 155.191.255.254155.191.255.255262,142
241155.192.0.0/14155.192.0.1 to 155.195.255.254155.195.255.255262,142
242155.196.0.0/14155.196.0.1 to 155.199.255.254155.199.255.255262,142
243155.200.0.0/14155.200.0.1 to 155.203.255.254155.203.255.255262,142
244155.204.0.0/14155.204.0.1 to 155.207.255.254155.207.255.255262,142
245155.208.0.0/14155.208.0.1 to 155.211.255.254155.211.255.255262,142
246155.212.0.0/14155.212.0.1 to 155.215.255.254155.215.255.255262,142
247155.216.0.0/14155.216.0.1 to 155.219.255.254155.219.255.255262,142
248155.220.0.0/14155.220.0.1 to 155.223.255.254155.223.255.255262,142
249155.224.0.0/14155.224.0.1 to 155.227.255.254155.227.255.255262,142
250155.228.0.0/14155.228.0.1 to 155.231.255.254155.231.255.255262,142
251155.232.0.0/14155.232.0.1 to 155.235.255.254155.235.255.255262,142
252155.236.0.0/14155.236.0.1 to 155.239.255.254155.239.255.255262,142
253155.240.0.0/14155.240.0.1 to 155.243.255.254155.243.255.255262,142
254155.244.0.0/14155.244.0.1 to 155.247.255.254155.247.255.255262,142
255155.248.0.0/14155.248.0.1 to 155.251.255.254155.251.255.255262,142
256155.252.0.0/14155.252.0.1 to 155.255.255.254155.255.255.255262,142

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.