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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.

Network175.76.0.0/14
Usable hosts262,142
Subnet mask255.252.0.0
Addresses262,144
Network address
175.76.0.0
Broadcast address
175.79.255.255
First usable
175.76.0.1
Last usable
175.79.255.254
Usable hosts
262,142 (262,144 less the network and broadcast addresses)
Subnet mask
255.252.0.0
Wildcard mask
0.3.255.255 (Cisco ACLs, OSPF)
Prefix length
/14
Type
Public public
Old class
B (default /16)
As numbers
Hex AF4C0000 · Integer 2940993536 to 2941255679
Reverse DNS zones
76.175.in-addr.arpa
77.175.in-addr.arpa
78.175.in-addr.arpa
79.175.in-addr.arpa
/14 is not on a 8-bit boundary, so it takes 4 /16 zones.
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address10101111.01001100.00000000.00000000175.76.0.0
Subnet mask11111111.11111100.00000000.00000000255.252.0.0
Network10101111.01001100.00000000.00000000175.76.0.0
Broadcast10101111.01001111.11111111.11111111175.79.255.255
Split into smaller subnets/22
/15 (2)/16 (4)/17 (8)/18 (16)/19 (32)/20 (64)/21 (128)/22 (256)/23 (512)/24 (1,024)/25 (2,048)/26 (4,096)

175.76.0.0/14 makes 256 subnets of /22.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
1175.76.0.0/22175.76.0.1 to 175.76.3.254175.76.3.2551,022
2175.76.4.0/22175.76.4.1 to 175.76.7.254175.76.7.2551,022
3175.76.8.0/22175.76.8.1 to 175.76.11.254175.76.11.2551,022
4175.76.12.0/22175.76.12.1 to 175.76.15.254175.76.15.2551,022
5175.76.16.0/22175.76.16.1 to 175.76.19.254175.76.19.2551,022
6175.76.20.0/22175.76.20.1 to 175.76.23.254175.76.23.2551,022
7175.76.24.0/22175.76.24.1 to 175.76.27.254175.76.27.2551,022
8175.76.28.0/22175.76.28.1 to 175.76.31.254175.76.31.2551,022
9175.76.32.0/22175.76.32.1 to 175.76.35.254175.76.35.2551,022
10175.76.36.0/22175.76.36.1 to 175.76.39.254175.76.39.2551,022
11175.76.40.0/22175.76.40.1 to 175.76.43.254175.76.43.2551,022
12175.76.44.0/22175.76.44.1 to 175.76.47.254175.76.47.2551,022
13175.76.48.0/22175.76.48.1 to 175.76.51.254175.76.51.2551,022
14175.76.52.0/22175.76.52.1 to 175.76.55.254175.76.55.2551,022
15175.76.56.0/22175.76.56.1 to 175.76.59.254175.76.59.2551,022
16175.76.60.0/22175.76.60.1 to 175.76.63.254175.76.63.2551,022
17175.76.64.0/22175.76.64.1 to 175.76.67.254175.76.67.2551,022
18175.76.68.0/22175.76.68.1 to 175.76.71.254175.76.71.2551,022
19175.76.72.0/22175.76.72.1 to 175.76.75.254175.76.75.2551,022
20175.76.76.0/22175.76.76.1 to 175.76.79.254175.76.79.2551,022
21175.76.80.0/22175.76.80.1 to 175.76.83.254175.76.83.2551,022
22175.76.84.0/22175.76.84.1 to 175.76.87.254175.76.87.2551,022
23175.76.88.0/22175.76.88.1 to 175.76.91.254175.76.91.2551,022
24175.76.92.0/22175.76.92.1 to 175.76.95.254175.76.95.2551,022
25175.76.96.0/22175.76.96.1 to 175.76.99.254175.76.99.2551,022
26175.76.100.0/22175.76.100.1 to 175.76.103.254175.76.103.2551,022
27175.76.104.0/22175.76.104.1 to 175.76.107.254175.76.107.2551,022
28175.76.108.0/22175.76.108.1 to 175.76.111.254175.76.111.2551,022
29175.76.112.0/22175.76.112.1 to 175.76.115.254175.76.115.2551,022
30175.76.116.0/22175.76.116.1 to 175.76.119.254175.76.119.2551,022
31175.76.120.0/22175.76.120.1 to 175.76.123.254175.76.123.2551,022
32175.76.124.0/22175.76.124.1 to 175.76.127.254175.76.127.2551,022
33175.76.128.0/22175.76.128.1 to 175.76.131.254175.76.131.2551,022
34175.76.132.0/22175.76.132.1 to 175.76.135.254175.76.135.2551,022
35175.76.136.0/22175.76.136.1 to 175.76.139.254175.76.139.2551,022
36175.76.140.0/22175.76.140.1 to 175.76.143.254175.76.143.2551,022
37175.76.144.0/22175.76.144.1 to 175.76.147.254175.76.147.2551,022
38175.76.148.0/22175.76.148.1 to 175.76.151.254175.76.151.2551,022
39175.76.152.0/22175.76.152.1 to 175.76.155.254175.76.155.2551,022
40175.76.156.0/22175.76.156.1 to 175.76.159.254175.76.159.2551,022
41175.76.160.0/22175.76.160.1 to 175.76.163.254175.76.163.2551,022
42175.76.164.0/22175.76.164.1 to 175.76.167.254175.76.167.2551,022
43175.76.168.0/22175.76.168.1 to 175.76.171.254175.76.171.2551,022
44175.76.172.0/22175.76.172.1 to 175.76.175.254175.76.175.2551,022
45175.76.176.0/22175.76.176.1 to 175.76.179.254175.76.179.2551,022
46175.76.180.0/22175.76.180.1 to 175.76.183.254175.76.183.2551,022
47175.76.184.0/22175.76.184.1 to 175.76.187.254175.76.187.2551,022
48175.76.188.0/22175.76.188.1 to 175.76.191.254175.76.191.2551,022
49175.76.192.0/22175.76.192.1 to 175.76.195.254175.76.195.2551,022
50175.76.196.0/22175.76.196.1 to 175.76.199.254175.76.199.2551,022
51175.76.200.0/22175.76.200.1 to 175.76.203.254175.76.203.2551,022
52175.76.204.0/22175.76.204.1 to 175.76.207.254175.76.207.2551,022
53175.76.208.0/22175.76.208.1 to 175.76.211.254175.76.211.2551,022
54175.76.212.0/22175.76.212.1 to 175.76.215.254175.76.215.2551,022
55175.76.216.0/22175.76.216.1 to 175.76.219.254175.76.219.2551,022
56175.76.220.0/22175.76.220.1 to 175.76.223.254175.76.223.2551,022
57175.76.224.0/22175.76.224.1 to 175.76.227.254175.76.227.2551,022
58175.76.228.0/22175.76.228.1 to 175.76.231.254175.76.231.2551,022
59175.76.232.0/22175.76.232.1 to 175.76.235.254175.76.235.2551,022
60175.76.236.0/22175.76.236.1 to 175.76.239.254175.76.239.2551,022
61175.76.240.0/22175.76.240.1 to 175.76.243.254175.76.243.2551,022
62175.76.244.0/22175.76.244.1 to 175.76.247.254175.76.247.2551,022
63175.76.248.0/22175.76.248.1 to 175.76.251.254175.76.251.2551,022
64175.76.252.0/22175.76.252.1 to 175.76.255.254175.76.255.2551,022
65175.77.0.0/22175.77.0.1 to 175.77.3.254175.77.3.2551,022
66175.77.4.0/22175.77.4.1 to 175.77.7.254175.77.7.2551,022
67175.77.8.0/22175.77.8.1 to 175.77.11.254175.77.11.2551,022
68175.77.12.0/22175.77.12.1 to 175.77.15.254175.77.15.2551,022
69175.77.16.0/22175.77.16.1 to 175.77.19.254175.77.19.2551,022
70175.77.20.0/22175.77.20.1 to 175.77.23.254175.77.23.2551,022
71175.77.24.0/22175.77.24.1 to 175.77.27.254175.77.27.2551,022
72175.77.28.0/22175.77.28.1 to 175.77.31.254175.77.31.2551,022
73175.77.32.0/22175.77.32.1 to 175.77.35.254175.77.35.2551,022
74175.77.36.0/22175.77.36.1 to 175.77.39.254175.77.39.2551,022
75175.77.40.0/22175.77.40.1 to 175.77.43.254175.77.43.2551,022
76175.77.44.0/22175.77.44.1 to 175.77.47.254175.77.47.2551,022
77175.77.48.0/22175.77.48.1 to 175.77.51.254175.77.51.2551,022
78175.77.52.0/22175.77.52.1 to 175.77.55.254175.77.55.2551,022
79175.77.56.0/22175.77.56.1 to 175.77.59.254175.77.59.2551,022
80175.77.60.0/22175.77.60.1 to 175.77.63.254175.77.63.2551,022
81175.77.64.0/22175.77.64.1 to 175.77.67.254175.77.67.2551,022
82175.77.68.0/22175.77.68.1 to 175.77.71.254175.77.71.2551,022
83175.77.72.0/22175.77.72.1 to 175.77.75.254175.77.75.2551,022
84175.77.76.0/22175.77.76.1 to 175.77.79.254175.77.79.2551,022
85175.77.80.0/22175.77.80.1 to 175.77.83.254175.77.83.2551,022
86175.77.84.0/22175.77.84.1 to 175.77.87.254175.77.87.2551,022
87175.77.88.0/22175.77.88.1 to 175.77.91.254175.77.91.2551,022
88175.77.92.0/22175.77.92.1 to 175.77.95.254175.77.95.2551,022
89175.77.96.0/22175.77.96.1 to 175.77.99.254175.77.99.2551,022
90175.77.100.0/22175.77.100.1 to 175.77.103.254175.77.103.2551,022
91175.77.104.0/22175.77.104.1 to 175.77.107.254175.77.107.2551,022
92175.77.108.0/22175.77.108.1 to 175.77.111.254175.77.111.2551,022
93175.77.112.0/22175.77.112.1 to 175.77.115.254175.77.115.2551,022
94175.77.116.0/22175.77.116.1 to 175.77.119.254175.77.119.2551,022
95175.77.120.0/22175.77.120.1 to 175.77.123.254175.77.123.2551,022
96175.77.124.0/22175.77.124.1 to 175.77.127.254175.77.127.2551,022
97175.77.128.0/22175.77.128.1 to 175.77.131.254175.77.131.2551,022
98175.77.132.0/22175.77.132.1 to 175.77.135.254175.77.135.2551,022
99175.77.136.0/22175.77.136.1 to 175.77.139.254175.77.139.2551,022
100175.77.140.0/22175.77.140.1 to 175.77.143.254175.77.143.2551,022
101175.77.144.0/22175.77.144.1 to 175.77.147.254175.77.147.2551,022
102175.77.148.0/22175.77.148.1 to 175.77.151.254175.77.151.2551,022
103175.77.152.0/22175.77.152.1 to 175.77.155.254175.77.155.2551,022
104175.77.156.0/22175.77.156.1 to 175.77.159.254175.77.159.2551,022
105175.77.160.0/22175.77.160.1 to 175.77.163.254175.77.163.2551,022
106175.77.164.0/22175.77.164.1 to 175.77.167.254175.77.167.2551,022
107175.77.168.0/22175.77.168.1 to 175.77.171.254175.77.171.2551,022
108175.77.172.0/22175.77.172.1 to 175.77.175.254175.77.175.2551,022
109175.77.176.0/22175.77.176.1 to 175.77.179.254175.77.179.2551,022
110175.77.180.0/22175.77.180.1 to 175.77.183.254175.77.183.2551,022
111175.77.184.0/22175.77.184.1 to 175.77.187.254175.77.187.2551,022
112175.77.188.0/22175.77.188.1 to 175.77.191.254175.77.191.2551,022
113175.77.192.0/22175.77.192.1 to 175.77.195.254175.77.195.2551,022
114175.77.196.0/22175.77.196.1 to 175.77.199.254175.77.199.2551,022
115175.77.200.0/22175.77.200.1 to 175.77.203.254175.77.203.2551,022
116175.77.204.0/22175.77.204.1 to 175.77.207.254175.77.207.2551,022
117175.77.208.0/22175.77.208.1 to 175.77.211.254175.77.211.2551,022
118175.77.212.0/22175.77.212.1 to 175.77.215.254175.77.215.2551,022
119175.77.216.0/22175.77.216.1 to 175.77.219.254175.77.219.2551,022
120175.77.220.0/22175.77.220.1 to 175.77.223.254175.77.223.2551,022
121175.77.224.0/22175.77.224.1 to 175.77.227.254175.77.227.2551,022
122175.77.228.0/22175.77.228.1 to 175.77.231.254175.77.231.2551,022
123175.77.232.0/22175.77.232.1 to 175.77.235.254175.77.235.2551,022
124175.77.236.0/22175.77.236.1 to 175.77.239.254175.77.239.2551,022
125175.77.240.0/22175.77.240.1 to 175.77.243.254175.77.243.2551,022
126175.77.244.0/22175.77.244.1 to 175.77.247.254175.77.247.2551,022
127175.77.248.0/22175.77.248.1 to 175.77.251.254175.77.251.2551,022
128175.77.252.0/22175.77.252.1 to 175.77.255.254175.77.255.2551,022
129175.78.0.0/22175.78.0.1 to 175.78.3.254175.78.3.2551,022
130175.78.4.0/22175.78.4.1 to 175.78.7.254175.78.7.2551,022
131175.78.8.0/22175.78.8.1 to 175.78.11.254175.78.11.2551,022
132175.78.12.0/22175.78.12.1 to 175.78.15.254175.78.15.2551,022
133175.78.16.0/22175.78.16.1 to 175.78.19.254175.78.19.2551,022
134175.78.20.0/22175.78.20.1 to 175.78.23.254175.78.23.2551,022
135175.78.24.0/22175.78.24.1 to 175.78.27.254175.78.27.2551,022
136175.78.28.0/22175.78.28.1 to 175.78.31.254175.78.31.2551,022
137175.78.32.0/22175.78.32.1 to 175.78.35.254175.78.35.2551,022
138175.78.36.0/22175.78.36.1 to 175.78.39.254175.78.39.2551,022
139175.78.40.0/22175.78.40.1 to 175.78.43.254175.78.43.2551,022
140175.78.44.0/22175.78.44.1 to 175.78.47.254175.78.47.2551,022
141175.78.48.0/22175.78.48.1 to 175.78.51.254175.78.51.2551,022
142175.78.52.0/22175.78.52.1 to 175.78.55.254175.78.55.2551,022
143175.78.56.0/22175.78.56.1 to 175.78.59.254175.78.59.2551,022
144175.78.60.0/22175.78.60.1 to 175.78.63.254175.78.63.2551,022
145175.78.64.0/22175.78.64.1 to 175.78.67.254175.78.67.2551,022
146175.78.68.0/22175.78.68.1 to 175.78.71.254175.78.71.2551,022
147175.78.72.0/22175.78.72.1 to 175.78.75.254175.78.75.2551,022
148175.78.76.0/22175.78.76.1 to 175.78.79.254175.78.79.2551,022
149175.78.80.0/22175.78.80.1 to 175.78.83.254175.78.83.2551,022
150175.78.84.0/22175.78.84.1 to 175.78.87.254175.78.87.2551,022
151175.78.88.0/22175.78.88.1 to 175.78.91.254175.78.91.2551,022
152175.78.92.0/22175.78.92.1 to 175.78.95.254175.78.95.2551,022
153175.78.96.0/22175.78.96.1 to 175.78.99.254175.78.99.2551,022
154175.78.100.0/22175.78.100.1 to 175.78.103.254175.78.103.2551,022
155175.78.104.0/22175.78.104.1 to 175.78.107.254175.78.107.2551,022
156175.78.108.0/22175.78.108.1 to 175.78.111.254175.78.111.2551,022
157175.78.112.0/22175.78.112.1 to 175.78.115.254175.78.115.2551,022
158175.78.116.0/22175.78.116.1 to 175.78.119.254175.78.119.2551,022
159175.78.120.0/22175.78.120.1 to 175.78.123.254175.78.123.2551,022
160175.78.124.0/22175.78.124.1 to 175.78.127.254175.78.127.2551,022
161175.78.128.0/22175.78.128.1 to 175.78.131.254175.78.131.2551,022
162175.78.132.0/22175.78.132.1 to 175.78.135.254175.78.135.2551,022
163175.78.136.0/22175.78.136.1 to 175.78.139.254175.78.139.2551,022
164175.78.140.0/22175.78.140.1 to 175.78.143.254175.78.143.2551,022
165175.78.144.0/22175.78.144.1 to 175.78.147.254175.78.147.2551,022
166175.78.148.0/22175.78.148.1 to 175.78.151.254175.78.151.2551,022
167175.78.152.0/22175.78.152.1 to 175.78.155.254175.78.155.2551,022
168175.78.156.0/22175.78.156.1 to 175.78.159.254175.78.159.2551,022
169175.78.160.0/22175.78.160.1 to 175.78.163.254175.78.163.2551,022
170175.78.164.0/22175.78.164.1 to 175.78.167.254175.78.167.2551,022
171175.78.168.0/22175.78.168.1 to 175.78.171.254175.78.171.2551,022
172175.78.172.0/22175.78.172.1 to 175.78.175.254175.78.175.2551,022
173175.78.176.0/22175.78.176.1 to 175.78.179.254175.78.179.2551,022
174175.78.180.0/22175.78.180.1 to 175.78.183.254175.78.183.2551,022
175175.78.184.0/22175.78.184.1 to 175.78.187.254175.78.187.2551,022
176175.78.188.0/22175.78.188.1 to 175.78.191.254175.78.191.2551,022
177175.78.192.0/22175.78.192.1 to 175.78.195.254175.78.195.2551,022
178175.78.196.0/22175.78.196.1 to 175.78.199.254175.78.199.2551,022
179175.78.200.0/22175.78.200.1 to 175.78.203.254175.78.203.2551,022
180175.78.204.0/22175.78.204.1 to 175.78.207.254175.78.207.2551,022
181175.78.208.0/22175.78.208.1 to 175.78.211.254175.78.211.2551,022
182175.78.212.0/22175.78.212.1 to 175.78.215.254175.78.215.2551,022
183175.78.216.0/22175.78.216.1 to 175.78.219.254175.78.219.2551,022
184175.78.220.0/22175.78.220.1 to 175.78.223.254175.78.223.2551,022
185175.78.224.0/22175.78.224.1 to 175.78.227.254175.78.227.2551,022
186175.78.228.0/22175.78.228.1 to 175.78.231.254175.78.231.2551,022
187175.78.232.0/22175.78.232.1 to 175.78.235.254175.78.235.2551,022
188175.78.236.0/22175.78.236.1 to 175.78.239.254175.78.239.2551,022
189175.78.240.0/22175.78.240.1 to 175.78.243.254175.78.243.2551,022
190175.78.244.0/22175.78.244.1 to 175.78.247.254175.78.247.2551,022
191175.78.248.0/22175.78.248.1 to 175.78.251.254175.78.251.2551,022
192175.78.252.0/22175.78.252.1 to 175.78.255.254175.78.255.2551,022
193175.79.0.0/22175.79.0.1 to 175.79.3.254175.79.3.2551,022
194175.79.4.0/22175.79.4.1 to 175.79.7.254175.79.7.2551,022
195175.79.8.0/22175.79.8.1 to 175.79.11.254175.79.11.2551,022
196175.79.12.0/22175.79.12.1 to 175.79.15.254175.79.15.2551,022
197175.79.16.0/22175.79.16.1 to 175.79.19.254175.79.19.2551,022
198175.79.20.0/22175.79.20.1 to 175.79.23.254175.79.23.2551,022
199175.79.24.0/22175.79.24.1 to 175.79.27.254175.79.27.2551,022
200175.79.28.0/22175.79.28.1 to 175.79.31.254175.79.31.2551,022
201175.79.32.0/22175.79.32.1 to 175.79.35.254175.79.35.2551,022
202175.79.36.0/22175.79.36.1 to 175.79.39.254175.79.39.2551,022
203175.79.40.0/22175.79.40.1 to 175.79.43.254175.79.43.2551,022
204175.79.44.0/22175.79.44.1 to 175.79.47.254175.79.47.2551,022
205175.79.48.0/22175.79.48.1 to 175.79.51.254175.79.51.2551,022
206175.79.52.0/22175.79.52.1 to 175.79.55.254175.79.55.2551,022
207175.79.56.0/22175.79.56.1 to 175.79.59.254175.79.59.2551,022
208175.79.60.0/22175.79.60.1 to 175.79.63.254175.79.63.2551,022
209175.79.64.0/22175.79.64.1 to 175.79.67.254175.79.67.2551,022
210175.79.68.0/22175.79.68.1 to 175.79.71.254175.79.71.2551,022
211175.79.72.0/22175.79.72.1 to 175.79.75.254175.79.75.2551,022
212175.79.76.0/22175.79.76.1 to 175.79.79.254175.79.79.2551,022
213175.79.80.0/22175.79.80.1 to 175.79.83.254175.79.83.2551,022
214175.79.84.0/22175.79.84.1 to 175.79.87.254175.79.87.2551,022
215175.79.88.0/22175.79.88.1 to 175.79.91.254175.79.91.2551,022
216175.79.92.0/22175.79.92.1 to 175.79.95.254175.79.95.2551,022
217175.79.96.0/22175.79.96.1 to 175.79.99.254175.79.99.2551,022
218175.79.100.0/22175.79.100.1 to 175.79.103.254175.79.103.2551,022
219175.79.104.0/22175.79.104.1 to 175.79.107.254175.79.107.2551,022
220175.79.108.0/22175.79.108.1 to 175.79.111.254175.79.111.2551,022
221175.79.112.0/22175.79.112.1 to 175.79.115.254175.79.115.2551,022
222175.79.116.0/22175.79.116.1 to 175.79.119.254175.79.119.2551,022
223175.79.120.0/22175.79.120.1 to 175.79.123.254175.79.123.2551,022
224175.79.124.0/22175.79.124.1 to 175.79.127.254175.79.127.2551,022
225175.79.128.0/22175.79.128.1 to 175.79.131.254175.79.131.2551,022
226175.79.132.0/22175.79.132.1 to 175.79.135.254175.79.135.2551,022
227175.79.136.0/22175.79.136.1 to 175.79.139.254175.79.139.2551,022
228175.79.140.0/22175.79.140.1 to 175.79.143.254175.79.143.2551,022
229175.79.144.0/22175.79.144.1 to 175.79.147.254175.79.147.2551,022
230175.79.148.0/22175.79.148.1 to 175.79.151.254175.79.151.2551,022
231175.79.152.0/22175.79.152.1 to 175.79.155.254175.79.155.2551,022
232175.79.156.0/22175.79.156.1 to 175.79.159.254175.79.159.2551,022
233175.79.160.0/22175.79.160.1 to 175.79.163.254175.79.163.2551,022
234175.79.164.0/22175.79.164.1 to 175.79.167.254175.79.167.2551,022
235175.79.168.0/22175.79.168.1 to 175.79.171.254175.79.171.2551,022
236175.79.172.0/22175.79.172.1 to 175.79.175.254175.79.175.2551,022
237175.79.176.0/22175.79.176.1 to 175.79.179.254175.79.179.2551,022
238175.79.180.0/22175.79.180.1 to 175.79.183.254175.79.183.2551,022
239175.79.184.0/22175.79.184.1 to 175.79.187.254175.79.187.2551,022
240175.79.188.0/22175.79.188.1 to 175.79.191.254175.79.191.2551,022
241175.79.192.0/22175.79.192.1 to 175.79.195.254175.79.195.2551,022
242175.79.196.0/22175.79.196.1 to 175.79.199.254175.79.199.2551,022
243175.79.200.0/22175.79.200.1 to 175.79.203.254175.79.203.2551,022
244175.79.204.0/22175.79.204.1 to 175.79.207.254175.79.207.2551,022
245175.79.208.0/22175.79.208.1 to 175.79.211.254175.79.211.2551,022
246175.79.212.0/22175.79.212.1 to 175.79.215.254175.79.215.2551,022
247175.79.216.0/22175.79.216.1 to 175.79.219.254175.79.219.2551,022
248175.79.220.0/22175.79.220.1 to 175.79.223.254175.79.223.2551,022
249175.79.224.0/22175.79.224.1 to 175.79.227.254175.79.227.2551,022
250175.79.228.0/22175.79.228.1 to 175.79.231.254175.79.231.2551,022
251175.79.232.0/22175.79.232.1 to 175.79.235.254175.79.235.2551,022
252175.79.236.0/22175.79.236.1 to 175.79.239.254175.79.239.2551,022
253175.79.240.0/22175.79.240.1 to 175.79.243.254175.79.243.2551,022
254175.79.244.0/22175.79.244.1 to 175.79.247.254175.79.247.2551,022
255175.79.248.0/22175.79.248.1 to 175.79.251.254175.79.251.2551,022
256175.79.252.0/22175.79.252.1 to 175.79.255.254175.79.255.2551,022

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.