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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.

Network158.0.0.0/7
Usable hosts33,554,430
Subnet mask254.0.0.0
Addresses33,554,432
Network address
158.0.0.0
Broadcast address
159.255.255.255
First usable
158.0.0.1
Last usable
159.255.255.254
Usable hosts
33,554,430 (33,554,432 less the network and broadcast addresses)
Subnet mask
254.0.0.0
Wildcard mask
1.255.255.255 (Cisco ACLs, OSPF)
Prefix length
/7
Type
Public public
Old class
B (default /16)
As numbers
Hex 9E000000 · Integer 2650800128 to 2684354559
Reverse DNS zones
158.in-addr.arpa
159.in-addr.arpa
/7 is not on a 8-bit boundary, so it takes 2 /8 zones.
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address10011110.00000000.00000000.00000000158.0.0.0
Subnet mask11111110.00000000.00000000.00000000254.0.0.0
Network10011110.00000000.00000000.00000000158.0.0.0
Broadcast10011111.11111111.11111111.11111111159.255.255.255
Split into smaller subnets/16
/8 (2)/9 (4)/10 (8)/11 (16)/12 (32)/13 (64)/14 (128)/15 (256)/16 (512)/17 (1,024)/18 (2,048)/19 (4,096)

158.0.0.0/7 makes 512 subnets of /16; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
1158.0.0.0/16158.0.0.1 to 158.0.255.254158.0.255.25565,534
2158.1.0.0/16158.1.0.1 to 158.1.255.254158.1.255.25565,534
3158.2.0.0/16158.2.0.1 to 158.2.255.254158.2.255.25565,534
4158.3.0.0/16158.3.0.1 to 158.3.255.254158.3.255.25565,534
5158.4.0.0/16158.4.0.1 to 158.4.255.254158.4.255.25565,534
6158.5.0.0/16158.5.0.1 to 158.5.255.254158.5.255.25565,534
7158.6.0.0/16158.6.0.1 to 158.6.255.254158.6.255.25565,534
8158.7.0.0/16158.7.0.1 to 158.7.255.254158.7.255.25565,534
9158.8.0.0/16158.8.0.1 to 158.8.255.254158.8.255.25565,534
10158.9.0.0/16158.9.0.1 to 158.9.255.254158.9.255.25565,534
11158.10.0.0/16158.10.0.1 to 158.10.255.254158.10.255.25565,534
12158.11.0.0/16158.11.0.1 to 158.11.255.254158.11.255.25565,534
13158.12.0.0/16158.12.0.1 to 158.12.255.254158.12.255.25565,534
14158.13.0.0/16158.13.0.1 to 158.13.255.254158.13.255.25565,534
15158.14.0.0/16158.14.0.1 to 158.14.255.254158.14.255.25565,534
16158.15.0.0/16158.15.0.1 to 158.15.255.254158.15.255.25565,534
17158.16.0.0/16158.16.0.1 to 158.16.255.254158.16.255.25565,534
18158.17.0.0/16158.17.0.1 to 158.17.255.254158.17.255.25565,534
19158.18.0.0/16158.18.0.1 to 158.18.255.254158.18.255.25565,534
20158.19.0.0/16158.19.0.1 to 158.19.255.254158.19.255.25565,534
21158.20.0.0/16158.20.0.1 to 158.20.255.254158.20.255.25565,534
22158.21.0.0/16158.21.0.1 to 158.21.255.254158.21.255.25565,534
23158.22.0.0/16158.22.0.1 to 158.22.255.254158.22.255.25565,534
24158.23.0.0/16158.23.0.1 to 158.23.255.254158.23.255.25565,534
25158.24.0.0/16158.24.0.1 to 158.24.255.254158.24.255.25565,534
26158.25.0.0/16158.25.0.1 to 158.25.255.254158.25.255.25565,534
27158.26.0.0/16158.26.0.1 to 158.26.255.254158.26.255.25565,534
28158.27.0.0/16158.27.0.1 to 158.27.255.254158.27.255.25565,534
29158.28.0.0/16158.28.0.1 to 158.28.255.254158.28.255.25565,534
30158.29.0.0/16158.29.0.1 to 158.29.255.254158.29.255.25565,534
31158.30.0.0/16158.30.0.1 to 158.30.255.254158.30.255.25565,534
32158.31.0.0/16158.31.0.1 to 158.31.255.254158.31.255.25565,534
33158.32.0.0/16158.32.0.1 to 158.32.255.254158.32.255.25565,534
34158.33.0.0/16158.33.0.1 to 158.33.255.254158.33.255.25565,534
35158.34.0.0/16158.34.0.1 to 158.34.255.254158.34.255.25565,534
36158.35.0.0/16158.35.0.1 to 158.35.255.254158.35.255.25565,534
37158.36.0.0/16158.36.0.1 to 158.36.255.254158.36.255.25565,534
38158.37.0.0/16158.37.0.1 to 158.37.255.254158.37.255.25565,534
39158.38.0.0/16158.38.0.1 to 158.38.255.254158.38.255.25565,534
40158.39.0.0/16158.39.0.1 to 158.39.255.254158.39.255.25565,534
41158.40.0.0/16158.40.0.1 to 158.40.255.254158.40.255.25565,534
42158.41.0.0/16158.41.0.1 to 158.41.255.254158.41.255.25565,534
43158.42.0.0/16158.42.0.1 to 158.42.255.254158.42.255.25565,534
44158.43.0.0/16158.43.0.1 to 158.43.255.254158.43.255.25565,534
45158.44.0.0/16158.44.0.1 to 158.44.255.254158.44.255.25565,534
46158.45.0.0/16158.45.0.1 to 158.45.255.254158.45.255.25565,534
47158.46.0.0/16158.46.0.1 to 158.46.255.254158.46.255.25565,534
48158.47.0.0/16158.47.0.1 to 158.47.255.254158.47.255.25565,534
49158.48.0.0/16158.48.0.1 to 158.48.255.254158.48.255.25565,534
50158.49.0.0/16158.49.0.1 to 158.49.255.254158.49.255.25565,534
51158.50.0.0/16158.50.0.1 to 158.50.255.254158.50.255.25565,534
52158.51.0.0/16158.51.0.1 to 158.51.255.254158.51.255.25565,534
53158.52.0.0/16158.52.0.1 to 158.52.255.254158.52.255.25565,534
54158.53.0.0/16158.53.0.1 to 158.53.255.254158.53.255.25565,534
55158.54.0.0/16158.54.0.1 to 158.54.255.254158.54.255.25565,534
56158.55.0.0/16158.55.0.1 to 158.55.255.254158.55.255.25565,534
57158.56.0.0/16158.56.0.1 to 158.56.255.254158.56.255.25565,534
58158.57.0.0/16158.57.0.1 to 158.57.255.254158.57.255.25565,534
59158.58.0.0/16158.58.0.1 to 158.58.255.254158.58.255.25565,534
60158.59.0.0/16158.59.0.1 to 158.59.255.254158.59.255.25565,534
61158.60.0.0/16158.60.0.1 to 158.60.255.254158.60.255.25565,534
62158.61.0.0/16158.61.0.1 to 158.61.255.254158.61.255.25565,534
63158.62.0.0/16158.62.0.1 to 158.62.255.254158.62.255.25565,534
64158.63.0.0/16158.63.0.1 to 158.63.255.254158.63.255.25565,534
65158.64.0.0/16158.64.0.1 to 158.64.255.254158.64.255.25565,534
66158.65.0.0/16158.65.0.1 to 158.65.255.254158.65.255.25565,534
67158.66.0.0/16158.66.0.1 to 158.66.255.254158.66.255.25565,534
68158.67.0.0/16158.67.0.1 to 158.67.255.254158.67.255.25565,534
69158.68.0.0/16158.68.0.1 to 158.68.255.254158.68.255.25565,534
70158.69.0.0/16158.69.0.1 to 158.69.255.254158.69.255.25565,534
71158.70.0.0/16158.70.0.1 to 158.70.255.254158.70.255.25565,534
72158.71.0.0/16158.71.0.1 to 158.71.255.254158.71.255.25565,534
73158.72.0.0/16158.72.0.1 to 158.72.255.254158.72.255.25565,534
74158.73.0.0/16158.73.0.1 to 158.73.255.254158.73.255.25565,534
75158.74.0.0/16158.74.0.1 to 158.74.255.254158.74.255.25565,534
76158.75.0.0/16158.75.0.1 to 158.75.255.254158.75.255.25565,534
77158.76.0.0/16158.76.0.1 to 158.76.255.254158.76.255.25565,534
78158.77.0.0/16158.77.0.1 to 158.77.255.254158.77.255.25565,534
79158.78.0.0/16158.78.0.1 to 158.78.255.254158.78.255.25565,534
80158.79.0.0/16158.79.0.1 to 158.79.255.254158.79.255.25565,534
81158.80.0.0/16158.80.0.1 to 158.80.255.254158.80.255.25565,534
82158.81.0.0/16158.81.0.1 to 158.81.255.254158.81.255.25565,534
83158.82.0.0/16158.82.0.1 to 158.82.255.254158.82.255.25565,534
84158.83.0.0/16158.83.0.1 to 158.83.255.254158.83.255.25565,534
85158.84.0.0/16158.84.0.1 to 158.84.255.254158.84.255.25565,534
86158.85.0.0/16158.85.0.1 to 158.85.255.254158.85.255.25565,534
87158.86.0.0/16158.86.0.1 to 158.86.255.254158.86.255.25565,534
88158.87.0.0/16158.87.0.1 to 158.87.255.254158.87.255.25565,534
89158.88.0.0/16158.88.0.1 to 158.88.255.254158.88.255.25565,534
90158.89.0.0/16158.89.0.1 to 158.89.255.254158.89.255.25565,534
91158.90.0.0/16158.90.0.1 to 158.90.255.254158.90.255.25565,534
92158.91.0.0/16158.91.0.1 to 158.91.255.254158.91.255.25565,534
93158.92.0.0/16158.92.0.1 to 158.92.255.254158.92.255.25565,534
94158.93.0.0/16158.93.0.1 to 158.93.255.254158.93.255.25565,534
95158.94.0.0/16158.94.0.1 to 158.94.255.254158.94.255.25565,534
96158.95.0.0/16158.95.0.1 to 158.95.255.254158.95.255.25565,534
97158.96.0.0/16158.96.0.1 to 158.96.255.254158.96.255.25565,534
98158.97.0.0/16158.97.0.1 to 158.97.255.254158.97.255.25565,534
99158.98.0.0/16158.98.0.1 to 158.98.255.254158.98.255.25565,534
100158.99.0.0/16158.99.0.1 to 158.99.255.254158.99.255.25565,534
101158.100.0.0/16158.100.0.1 to 158.100.255.254158.100.255.25565,534
102158.101.0.0/16158.101.0.1 to 158.101.255.254158.101.255.25565,534
103158.102.0.0/16158.102.0.1 to 158.102.255.254158.102.255.25565,534
104158.103.0.0/16158.103.0.1 to 158.103.255.254158.103.255.25565,534
105158.104.0.0/16158.104.0.1 to 158.104.255.254158.104.255.25565,534
106158.105.0.0/16158.105.0.1 to 158.105.255.254158.105.255.25565,534
107158.106.0.0/16158.106.0.1 to 158.106.255.254158.106.255.25565,534
108158.107.0.0/16158.107.0.1 to 158.107.255.254158.107.255.25565,534
109158.108.0.0/16158.108.0.1 to 158.108.255.254158.108.255.25565,534
110158.109.0.0/16158.109.0.1 to 158.109.255.254158.109.255.25565,534
111158.110.0.0/16158.110.0.1 to 158.110.255.254158.110.255.25565,534
112158.111.0.0/16158.111.0.1 to 158.111.255.254158.111.255.25565,534
113158.112.0.0/16158.112.0.1 to 158.112.255.254158.112.255.25565,534
114158.113.0.0/16158.113.0.1 to 158.113.255.254158.113.255.25565,534
115158.114.0.0/16158.114.0.1 to 158.114.255.254158.114.255.25565,534
116158.115.0.0/16158.115.0.1 to 158.115.255.254158.115.255.25565,534
117158.116.0.0/16158.116.0.1 to 158.116.255.254158.116.255.25565,534
118158.117.0.0/16158.117.0.1 to 158.117.255.254158.117.255.25565,534
119158.118.0.0/16158.118.0.1 to 158.118.255.254158.118.255.25565,534
120158.119.0.0/16158.119.0.1 to 158.119.255.254158.119.255.25565,534
121158.120.0.0/16158.120.0.1 to 158.120.255.254158.120.255.25565,534
122158.121.0.0/16158.121.0.1 to 158.121.255.254158.121.255.25565,534
123158.122.0.0/16158.122.0.1 to 158.122.255.254158.122.255.25565,534
124158.123.0.0/16158.123.0.1 to 158.123.255.254158.123.255.25565,534
125158.124.0.0/16158.124.0.1 to 158.124.255.254158.124.255.25565,534
126158.125.0.0/16158.125.0.1 to 158.125.255.254158.125.255.25565,534
127158.126.0.0/16158.126.0.1 to 158.126.255.254158.126.255.25565,534
128158.127.0.0/16158.127.0.1 to 158.127.255.254158.127.255.25565,534
129158.128.0.0/16158.128.0.1 to 158.128.255.254158.128.255.25565,534
130158.129.0.0/16158.129.0.1 to 158.129.255.254158.129.255.25565,534
131158.130.0.0/16158.130.0.1 to 158.130.255.254158.130.255.25565,534
132158.131.0.0/16158.131.0.1 to 158.131.255.254158.131.255.25565,534
133158.132.0.0/16158.132.0.1 to 158.132.255.254158.132.255.25565,534
134158.133.0.0/16158.133.0.1 to 158.133.255.254158.133.255.25565,534
135158.134.0.0/16158.134.0.1 to 158.134.255.254158.134.255.25565,534
136158.135.0.0/16158.135.0.1 to 158.135.255.254158.135.255.25565,534
137158.136.0.0/16158.136.0.1 to 158.136.255.254158.136.255.25565,534
138158.137.0.0/16158.137.0.1 to 158.137.255.254158.137.255.25565,534
139158.138.0.0/16158.138.0.1 to 158.138.255.254158.138.255.25565,534
140158.139.0.0/16158.139.0.1 to 158.139.255.254158.139.255.25565,534
141158.140.0.0/16158.140.0.1 to 158.140.255.254158.140.255.25565,534
142158.141.0.0/16158.141.0.1 to 158.141.255.254158.141.255.25565,534
143158.142.0.0/16158.142.0.1 to 158.142.255.254158.142.255.25565,534
144158.143.0.0/16158.143.0.1 to 158.143.255.254158.143.255.25565,534
145158.144.0.0/16158.144.0.1 to 158.144.255.254158.144.255.25565,534
146158.145.0.0/16158.145.0.1 to 158.145.255.254158.145.255.25565,534
147158.146.0.0/16158.146.0.1 to 158.146.255.254158.146.255.25565,534
148158.147.0.0/16158.147.0.1 to 158.147.255.254158.147.255.25565,534
149158.148.0.0/16158.148.0.1 to 158.148.255.254158.148.255.25565,534
150158.149.0.0/16158.149.0.1 to 158.149.255.254158.149.255.25565,534
151158.150.0.0/16158.150.0.1 to 158.150.255.254158.150.255.25565,534
152158.151.0.0/16158.151.0.1 to 158.151.255.254158.151.255.25565,534
153158.152.0.0/16158.152.0.1 to 158.152.255.254158.152.255.25565,534
154158.153.0.0/16158.153.0.1 to 158.153.255.254158.153.255.25565,534
155158.154.0.0/16158.154.0.1 to 158.154.255.254158.154.255.25565,534
156158.155.0.0/16158.155.0.1 to 158.155.255.254158.155.255.25565,534
157158.156.0.0/16158.156.0.1 to 158.156.255.254158.156.255.25565,534
158158.157.0.0/16158.157.0.1 to 158.157.255.254158.157.255.25565,534
159158.158.0.0/16158.158.0.1 to 158.158.255.254158.158.255.25565,534
160158.159.0.0/16158.159.0.1 to 158.159.255.254158.159.255.25565,534
161158.160.0.0/16158.160.0.1 to 158.160.255.254158.160.255.25565,534
162158.161.0.0/16158.161.0.1 to 158.161.255.254158.161.255.25565,534
163158.162.0.0/16158.162.0.1 to 158.162.255.254158.162.255.25565,534
164158.163.0.0/16158.163.0.1 to 158.163.255.254158.163.255.25565,534
165158.164.0.0/16158.164.0.1 to 158.164.255.254158.164.255.25565,534
166158.165.0.0/16158.165.0.1 to 158.165.255.254158.165.255.25565,534
167158.166.0.0/16158.166.0.1 to 158.166.255.254158.166.255.25565,534
168158.167.0.0/16158.167.0.1 to 158.167.255.254158.167.255.25565,534
169158.168.0.0/16158.168.0.1 to 158.168.255.254158.168.255.25565,534
170158.169.0.0/16158.169.0.1 to 158.169.255.254158.169.255.25565,534
171158.170.0.0/16158.170.0.1 to 158.170.255.254158.170.255.25565,534
172158.171.0.0/16158.171.0.1 to 158.171.255.254158.171.255.25565,534
173158.172.0.0/16158.172.0.1 to 158.172.255.254158.172.255.25565,534
174158.173.0.0/16158.173.0.1 to 158.173.255.254158.173.255.25565,534
175158.174.0.0/16158.174.0.1 to 158.174.255.254158.174.255.25565,534
176158.175.0.0/16158.175.0.1 to 158.175.255.254158.175.255.25565,534
177158.176.0.0/16158.176.0.1 to 158.176.255.254158.176.255.25565,534
178158.177.0.0/16158.177.0.1 to 158.177.255.254158.177.255.25565,534
179158.178.0.0/16158.178.0.1 to 158.178.255.254158.178.255.25565,534
180158.179.0.0/16158.179.0.1 to 158.179.255.254158.179.255.25565,534
181158.180.0.0/16158.180.0.1 to 158.180.255.254158.180.255.25565,534
182158.181.0.0/16158.181.0.1 to 158.181.255.254158.181.255.25565,534
183158.182.0.0/16158.182.0.1 to 158.182.255.254158.182.255.25565,534
184158.183.0.0/16158.183.0.1 to 158.183.255.254158.183.255.25565,534
185158.184.0.0/16158.184.0.1 to 158.184.255.254158.184.255.25565,534
186158.185.0.0/16158.185.0.1 to 158.185.255.254158.185.255.25565,534
187158.186.0.0/16158.186.0.1 to 158.186.255.254158.186.255.25565,534
188158.187.0.0/16158.187.0.1 to 158.187.255.254158.187.255.25565,534
189158.188.0.0/16158.188.0.1 to 158.188.255.254158.188.255.25565,534
190158.189.0.0/16158.189.0.1 to 158.189.255.254158.189.255.25565,534
191158.190.0.0/16158.190.0.1 to 158.190.255.254158.190.255.25565,534
192158.191.0.0/16158.191.0.1 to 158.191.255.254158.191.255.25565,534
193158.192.0.0/16158.192.0.1 to 158.192.255.254158.192.255.25565,534
194158.193.0.0/16158.193.0.1 to 158.193.255.254158.193.255.25565,534
195158.194.0.0/16158.194.0.1 to 158.194.255.254158.194.255.25565,534
196158.195.0.0/16158.195.0.1 to 158.195.255.254158.195.255.25565,534
197158.196.0.0/16158.196.0.1 to 158.196.255.254158.196.255.25565,534
198158.197.0.0/16158.197.0.1 to 158.197.255.254158.197.255.25565,534
199158.198.0.0/16158.198.0.1 to 158.198.255.254158.198.255.25565,534
200158.199.0.0/16158.199.0.1 to 158.199.255.254158.199.255.25565,534
201158.200.0.0/16158.200.0.1 to 158.200.255.254158.200.255.25565,534
202158.201.0.0/16158.201.0.1 to 158.201.255.254158.201.255.25565,534
203158.202.0.0/16158.202.0.1 to 158.202.255.254158.202.255.25565,534
204158.203.0.0/16158.203.0.1 to 158.203.255.254158.203.255.25565,534
205158.204.0.0/16158.204.0.1 to 158.204.255.254158.204.255.25565,534
206158.205.0.0/16158.205.0.1 to 158.205.255.254158.205.255.25565,534
207158.206.0.0/16158.206.0.1 to 158.206.255.254158.206.255.25565,534
208158.207.0.0/16158.207.0.1 to 158.207.255.254158.207.255.25565,534
209158.208.0.0/16158.208.0.1 to 158.208.255.254158.208.255.25565,534
210158.209.0.0/16158.209.0.1 to 158.209.255.254158.209.255.25565,534
211158.210.0.0/16158.210.0.1 to 158.210.255.254158.210.255.25565,534
212158.211.0.0/16158.211.0.1 to 158.211.255.254158.211.255.25565,534
213158.212.0.0/16158.212.0.1 to 158.212.255.254158.212.255.25565,534
214158.213.0.0/16158.213.0.1 to 158.213.255.254158.213.255.25565,534
215158.214.0.0/16158.214.0.1 to 158.214.255.254158.214.255.25565,534
216158.215.0.0/16158.215.0.1 to 158.215.255.254158.215.255.25565,534
217158.216.0.0/16158.216.0.1 to 158.216.255.254158.216.255.25565,534
218158.217.0.0/16158.217.0.1 to 158.217.255.254158.217.255.25565,534
219158.218.0.0/16158.218.0.1 to 158.218.255.254158.218.255.25565,534
220158.219.0.0/16158.219.0.1 to 158.219.255.254158.219.255.25565,534
221158.220.0.0/16158.220.0.1 to 158.220.255.254158.220.255.25565,534
222158.221.0.0/16158.221.0.1 to 158.221.255.254158.221.255.25565,534
223158.222.0.0/16158.222.0.1 to 158.222.255.254158.222.255.25565,534
224158.223.0.0/16158.223.0.1 to 158.223.255.254158.223.255.25565,534
225158.224.0.0/16158.224.0.1 to 158.224.255.254158.224.255.25565,534
226158.225.0.0/16158.225.0.1 to 158.225.255.254158.225.255.25565,534
227158.226.0.0/16158.226.0.1 to 158.226.255.254158.226.255.25565,534
228158.227.0.0/16158.227.0.1 to 158.227.255.254158.227.255.25565,534
229158.228.0.0/16158.228.0.1 to 158.228.255.254158.228.255.25565,534
230158.229.0.0/16158.229.0.1 to 158.229.255.254158.229.255.25565,534
231158.230.0.0/16158.230.0.1 to 158.230.255.254158.230.255.25565,534
232158.231.0.0/16158.231.0.1 to 158.231.255.254158.231.255.25565,534
233158.232.0.0/16158.232.0.1 to 158.232.255.254158.232.255.25565,534
234158.233.0.0/16158.233.0.1 to 158.233.255.254158.233.255.25565,534
235158.234.0.0/16158.234.0.1 to 158.234.255.254158.234.255.25565,534
236158.235.0.0/16158.235.0.1 to 158.235.255.254158.235.255.25565,534
237158.236.0.0/16158.236.0.1 to 158.236.255.254158.236.255.25565,534
238158.237.0.0/16158.237.0.1 to 158.237.255.254158.237.255.25565,534
239158.238.0.0/16158.238.0.1 to 158.238.255.254158.238.255.25565,534
240158.239.0.0/16158.239.0.1 to 158.239.255.254158.239.255.25565,534
241158.240.0.0/16158.240.0.1 to 158.240.255.254158.240.255.25565,534
242158.241.0.0/16158.241.0.1 to 158.241.255.254158.241.255.25565,534
243158.242.0.0/16158.242.0.1 to 158.242.255.254158.242.255.25565,534
244158.243.0.0/16158.243.0.1 to 158.243.255.254158.243.255.25565,534
245158.244.0.0/16158.244.0.1 to 158.244.255.254158.244.255.25565,534
246158.245.0.0/16158.245.0.1 to 158.245.255.254158.245.255.25565,534
247158.246.0.0/16158.246.0.1 to 158.246.255.254158.246.255.25565,534
248158.247.0.0/16158.247.0.1 to 158.247.255.254158.247.255.25565,534
249158.248.0.0/16158.248.0.1 to 158.248.255.254158.248.255.25565,534
250158.249.0.0/16158.249.0.1 to 158.249.255.254158.249.255.25565,534
251158.250.0.0/16158.250.0.1 to 158.250.255.254158.250.255.25565,534
252158.251.0.0/16158.251.0.1 to 158.251.255.254158.251.255.25565,534
253158.252.0.0/16158.252.0.1 to 158.252.255.254158.252.255.25565,534
254158.253.0.0/16158.253.0.1 to 158.253.255.254158.253.255.25565,534
255158.254.0.0/16158.254.0.1 to 158.254.255.254158.254.255.25565,534
256158.255.0.0/16158.255.0.1 to 158.255.255.254158.255.255.25565,534

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.