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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.

Network175.232.0.0/14
Usable hosts262,142
Subnet mask255.252.0.0
Addresses262,144
Network address
175.232.0.0
Broadcast address
175.235.255.255
First usable
175.232.0.1
Last usable
175.235.255.254
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 AFE80000 · Integer 2951217152 to 2951479295
Reverse DNS zones
232.175.in-addr.arpa
233.175.in-addr.arpa
234.175.in-addr.arpa
235.175.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
Address10101111.11101000.00000000.00000000175.232.0.0
Subnet mask11111111.11111100.00000000.00000000255.252.0.0
Network10101111.11101000.00000000.00000000175.232.0.0
Broadcast10101111.11101011.11111111.11111111175.235.255.255
Split into smaller subnets/24
/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)

175.232.0.0/14 makes 1,024 subnets of /24; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
1175.232.0.0/24175.232.0.1 to 175.232.0.254175.232.0.255254
2175.232.1.0/24175.232.1.1 to 175.232.1.254175.232.1.255254
3175.232.2.0/24175.232.2.1 to 175.232.2.254175.232.2.255254
4175.232.3.0/24175.232.3.1 to 175.232.3.254175.232.3.255254
5175.232.4.0/24175.232.4.1 to 175.232.4.254175.232.4.255254
6175.232.5.0/24175.232.5.1 to 175.232.5.254175.232.5.255254
7175.232.6.0/24175.232.6.1 to 175.232.6.254175.232.6.255254
8175.232.7.0/24175.232.7.1 to 175.232.7.254175.232.7.255254
9175.232.8.0/24175.232.8.1 to 175.232.8.254175.232.8.255254
10175.232.9.0/24175.232.9.1 to 175.232.9.254175.232.9.255254
11175.232.10.0/24175.232.10.1 to 175.232.10.254175.232.10.255254
12175.232.11.0/24175.232.11.1 to 175.232.11.254175.232.11.255254
13175.232.12.0/24175.232.12.1 to 175.232.12.254175.232.12.255254
14175.232.13.0/24175.232.13.1 to 175.232.13.254175.232.13.255254
15175.232.14.0/24175.232.14.1 to 175.232.14.254175.232.14.255254
16175.232.15.0/24175.232.15.1 to 175.232.15.254175.232.15.255254
17175.232.16.0/24175.232.16.1 to 175.232.16.254175.232.16.255254
18175.232.17.0/24175.232.17.1 to 175.232.17.254175.232.17.255254
19175.232.18.0/24175.232.18.1 to 175.232.18.254175.232.18.255254
20175.232.19.0/24175.232.19.1 to 175.232.19.254175.232.19.255254
21175.232.20.0/24175.232.20.1 to 175.232.20.254175.232.20.255254
22175.232.21.0/24175.232.21.1 to 175.232.21.254175.232.21.255254
23175.232.22.0/24175.232.22.1 to 175.232.22.254175.232.22.255254
24175.232.23.0/24175.232.23.1 to 175.232.23.254175.232.23.255254
25175.232.24.0/24175.232.24.1 to 175.232.24.254175.232.24.255254
26175.232.25.0/24175.232.25.1 to 175.232.25.254175.232.25.255254
27175.232.26.0/24175.232.26.1 to 175.232.26.254175.232.26.255254
28175.232.27.0/24175.232.27.1 to 175.232.27.254175.232.27.255254
29175.232.28.0/24175.232.28.1 to 175.232.28.254175.232.28.255254
30175.232.29.0/24175.232.29.1 to 175.232.29.254175.232.29.255254
31175.232.30.0/24175.232.30.1 to 175.232.30.254175.232.30.255254
32175.232.31.0/24175.232.31.1 to 175.232.31.254175.232.31.255254
33175.232.32.0/24175.232.32.1 to 175.232.32.254175.232.32.255254
34175.232.33.0/24175.232.33.1 to 175.232.33.254175.232.33.255254
35175.232.34.0/24175.232.34.1 to 175.232.34.254175.232.34.255254
36175.232.35.0/24175.232.35.1 to 175.232.35.254175.232.35.255254
37175.232.36.0/24175.232.36.1 to 175.232.36.254175.232.36.255254
38175.232.37.0/24175.232.37.1 to 175.232.37.254175.232.37.255254
39175.232.38.0/24175.232.38.1 to 175.232.38.254175.232.38.255254
40175.232.39.0/24175.232.39.1 to 175.232.39.254175.232.39.255254
41175.232.40.0/24175.232.40.1 to 175.232.40.254175.232.40.255254
42175.232.41.0/24175.232.41.1 to 175.232.41.254175.232.41.255254
43175.232.42.0/24175.232.42.1 to 175.232.42.254175.232.42.255254
44175.232.43.0/24175.232.43.1 to 175.232.43.254175.232.43.255254
45175.232.44.0/24175.232.44.1 to 175.232.44.254175.232.44.255254
46175.232.45.0/24175.232.45.1 to 175.232.45.254175.232.45.255254
47175.232.46.0/24175.232.46.1 to 175.232.46.254175.232.46.255254
48175.232.47.0/24175.232.47.1 to 175.232.47.254175.232.47.255254
49175.232.48.0/24175.232.48.1 to 175.232.48.254175.232.48.255254
50175.232.49.0/24175.232.49.1 to 175.232.49.254175.232.49.255254
51175.232.50.0/24175.232.50.1 to 175.232.50.254175.232.50.255254
52175.232.51.0/24175.232.51.1 to 175.232.51.254175.232.51.255254
53175.232.52.0/24175.232.52.1 to 175.232.52.254175.232.52.255254
54175.232.53.0/24175.232.53.1 to 175.232.53.254175.232.53.255254
55175.232.54.0/24175.232.54.1 to 175.232.54.254175.232.54.255254
56175.232.55.0/24175.232.55.1 to 175.232.55.254175.232.55.255254
57175.232.56.0/24175.232.56.1 to 175.232.56.254175.232.56.255254
58175.232.57.0/24175.232.57.1 to 175.232.57.254175.232.57.255254
59175.232.58.0/24175.232.58.1 to 175.232.58.254175.232.58.255254
60175.232.59.0/24175.232.59.1 to 175.232.59.254175.232.59.255254
61175.232.60.0/24175.232.60.1 to 175.232.60.254175.232.60.255254
62175.232.61.0/24175.232.61.1 to 175.232.61.254175.232.61.255254
63175.232.62.0/24175.232.62.1 to 175.232.62.254175.232.62.255254
64175.232.63.0/24175.232.63.1 to 175.232.63.254175.232.63.255254
65175.232.64.0/24175.232.64.1 to 175.232.64.254175.232.64.255254
66175.232.65.0/24175.232.65.1 to 175.232.65.254175.232.65.255254
67175.232.66.0/24175.232.66.1 to 175.232.66.254175.232.66.255254
68175.232.67.0/24175.232.67.1 to 175.232.67.254175.232.67.255254
69175.232.68.0/24175.232.68.1 to 175.232.68.254175.232.68.255254
70175.232.69.0/24175.232.69.1 to 175.232.69.254175.232.69.255254
71175.232.70.0/24175.232.70.1 to 175.232.70.254175.232.70.255254
72175.232.71.0/24175.232.71.1 to 175.232.71.254175.232.71.255254
73175.232.72.0/24175.232.72.1 to 175.232.72.254175.232.72.255254
74175.232.73.0/24175.232.73.1 to 175.232.73.254175.232.73.255254
75175.232.74.0/24175.232.74.1 to 175.232.74.254175.232.74.255254
76175.232.75.0/24175.232.75.1 to 175.232.75.254175.232.75.255254
77175.232.76.0/24175.232.76.1 to 175.232.76.254175.232.76.255254
78175.232.77.0/24175.232.77.1 to 175.232.77.254175.232.77.255254
79175.232.78.0/24175.232.78.1 to 175.232.78.254175.232.78.255254
80175.232.79.0/24175.232.79.1 to 175.232.79.254175.232.79.255254
81175.232.80.0/24175.232.80.1 to 175.232.80.254175.232.80.255254
82175.232.81.0/24175.232.81.1 to 175.232.81.254175.232.81.255254
83175.232.82.0/24175.232.82.1 to 175.232.82.254175.232.82.255254
84175.232.83.0/24175.232.83.1 to 175.232.83.254175.232.83.255254
85175.232.84.0/24175.232.84.1 to 175.232.84.254175.232.84.255254
86175.232.85.0/24175.232.85.1 to 175.232.85.254175.232.85.255254
87175.232.86.0/24175.232.86.1 to 175.232.86.254175.232.86.255254
88175.232.87.0/24175.232.87.1 to 175.232.87.254175.232.87.255254
89175.232.88.0/24175.232.88.1 to 175.232.88.254175.232.88.255254
90175.232.89.0/24175.232.89.1 to 175.232.89.254175.232.89.255254
91175.232.90.0/24175.232.90.1 to 175.232.90.254175.232.90.255254
92175.232.91.0/24175.232.91.1 to 175.232.91.254175.232.91.255254
93175.232.92.0/24175.232.92.1 to 175.232.92.254175.232.92.255254
94175.232.93.0/24175.232.93.1 to 175.232.93.254175.232.93.255254
95175.232.94.0/24175.232.94.1 to 175.232.94.254175.232.94.255254
96175.232.95.0/24175.232.95.1 to 175.232.95.254175.232.95.255254
97175.232.96.0/24175.232.96.1 to 175.232.96.254175.232.96.255254
98175.232.97.0/24175.232.97.1 to 175.232.97.254175.232.97.255254
99175.232.98.0/24175.232.98.1 to 175.232.98.254175.232.98.255254
100175.232.99.0/24175.232.99.1 to 175.232.99.254175.232.99.255254
101175.232.100.0/24175.232.100.1 to 175.232.100.254175.232.100.255254
102175.232.101.0/24175.232.101.1 to 175.232.101.254175.232.101.255254
103175.232.102.0/24175.232.102.1 to 175.232.102.254175.232.102.255254
104175.232.103.0/24175.232.103.1 to 175.232.103.254175.232.103.255254
105175.232.104.0/24175.232.104.1 to 175.232.104.254175.232.104.255254
106175.232.105.0/24175.232.105.1 to 175.232.105.254175.232.105.255254
107175.232.106.0/24175.232.106.1 to 175.232.106.254175.232.106.255254
108175.232.107.0/24175.232.107.1 to 175.232.107.254175.232.107.255254
109175.232.108.0/24175.232.108.1 to 175.232.108.254175.232.108.255254
110175.232.109.0/24175.232.109.1 to 175.232.109.254175.232.109.255254
111175.232.110.0/24175.232.110.1 to 175.232.110.254175.232.110.255254
112175.232.111.0/24175.232.111.1 to 175.232.111.254175.232.111.255254
113175.232.112.0/24175.232.112.1 to 175.232.112.254175.232.112.255254
114175.232.113.0/24175.232.113.1 to 175.232.113.254175.232.113.255254
115175.232.114.0/24175.232.114.1 to 175.232.114.254175.232.114.255254
116175.232.115.0/24175.232.115.1 to 175.232.115.254175.232.115.255254
117175.232.116.0/24175.232.116.1 to 175.232.116.254175.232.116.255254
118175.232.117.0/24175.232.117.1 to 175.232.117.254175.232.117.255254
119175.232.118.0/24175.232.118.1 to 175.232.118.254175.232.118.255254
120175.232.119.0/24175.232.119.1 to 175.232.119.254175.232.119.255254
121175.232.120.0/24175.232.120.1 to 175.232.120.254175.232.120.255254
122175.232.121.0/24175.232.121.1 to 175.232.121.254175.232.121.255254
123175.232.122.0/24175.232.122.1 to 175.232.122.254175.232.122.255254
124175.232.123.0/24175.232.123.1 to 175.232.123.254175.232.123.255254
125175.232.124.0/24175.232.124.1 to 175.232.124.254175.232.124.255254
126175.232.125.0/24175.232.125.1 to 175.232.125.254175.232.125.255254
127175.232.126.0/24175.232.126.1 to 175.232.126.254175.232.126.255254
128175.232.127.0/24175.232.127.1 to 175.232.127.254175.232.127.255254
129175.232.128.0/24175.232.128.1 to 175.232.128.254175.232.128.255254
130175.232.129.0/24175.232.129.1 to 175.232.129.254175.232.129.255254
131175.232.130.0/24175.232.130.1 to 175.232.130.254175.232.130.255254
132175.232.131.0/24175.232.131.1 to 175.232.131.254175.232.131.255254
133175.232.132.0/24175.232.132.1 to 175.232.132.254175.232.132.255254
134175.232.133.0/24175.232.133.1 to 175.232.133.254175.232.133.255254
135175.232.134.0/24175.232.134.1 to 175.232.134.254175.232.134.255254
136175.232.135.0/24175.232.135.1 to 175.232.135.254175.232.135.255254
137175.232.136.0/24175.232.136.1 to 175.232.136.254175.232.136.255254
138175.232.137.0/24175.232.137.1 to 175.232.137.254175.232.137.255254
139175.232.138.0/24175.232.138.1 to 175.232.138.254175.232.138.255254
140175.232.139.0/24175.232.139.1 to 175.232.139.254175.232.139.255254
141175.232.140.0/24175.232.140.1 to 175.232.140.254175.232.140.255254
142175.232.141.0/24175.232.141.1 to 175.232.141.254175.232.141.255254
143175.232.142.0/24175.232.142.1 to 175.232.142.254175.232.142.255254
144175.232.143.0/24175.232.143.1 to 175.232.143.254175.232.143.255254
145175.232.144.0/24175.232.144.1 to 175.232.144.254175.232.144.255254
146175.232.145.0/24175.232.145.1 to 175.232.145.254175.232.145.255254
147175.232.146.0/24175.232.146.1 to 175.232.146.254175.232.146.255254
148175.232.147.0/24175.232.147.1 to 175.232.147.254175.232.147.255254
149175.232.148.0/24175.232.148.1 to 175.232.148.254175.232.148.255254
150175.232.149.0/24175.232.149.1 to 175.232.149.254175.232.149.255254
151175.232.150.0/24175.232.150.1 to 175.232.150.254175.232.150.255254
152175.232.151.0/24175.232.151.1 to 175.232.151.254175.232.151.255254
153175.232.152.0/24175.232.152.1 to 175.232.152.254175.232.152.255254
154175.232.153.0/24175.232.153.1 to 175.232.153.254175.232.153.255254
155175.232.154.0/24175.232.154.1 to 175.232.154.254175.232.154.255254
156175.232.155.0/24175.232.155.1 to 175.232.155.254175.232.155.255254
157175.232.156.0/24175.232.156.1 to 175.232.156.254175.232.156.255254
158175.232.157.0/24175.232.157.1 to 175.232.157.254175.232.157.255254
159175.232.158.0/24175.232.158.1 to 175.232.158.254175.232.158.255254
160175.232.159.0/24175.232.159.1 to 175.232.159.254175.232.159.255254
161175.232.160.0/24175.232.160.1 to 175.232.160.254175.232.160.255254
162175.232.161.0/24175.232.161.1 to 175.232.161.254175.232.161.255254
163175.232.162.0/24175.232.162.1 to 175.232.162.254175.232.162.255254
164175.232.163.0/24175.232.163.1 to 175.232.163.254175.232.163.255254
165175.232.164.0/24175.232.164.1 to 175.232.164.254175.232.164.255254
166175.232.165.0/24175.232.165.1 to 175.232.165.254175.232.165.255254
167175.232.166.0/24175.232.166.1 to 175.232.166.254175.232.166.255254
168175.232.167.0/24175.232.167.1 to 175.232.167.254175.232.167.255254
169175.232.168.0/24175.232.168.1 to 175.232.168.254175.232.168.255254
170175.232.169.0/24175.232.169.1 to 175.232.169.254175.232.169.255254
171175.232.170.0/24175.232.170.1 to 175.232.170.254175.232.170.255254
172175.232.171.0/24175.232.171.1 to 175.232.171.254175.232.171.255254
173175.232.172.0/24175.232.172.1 to 175.232.172.254175.232.172.255254
174175.232.173.0/24175.232.173.1 to 175.232.173.254175.232.173.255254
175175.232.174.0/24175.232.174.1 to 175.232.174.254175.232.174.255254
176175.232.175.0/24175.232.175.1 to 175.232.175.254175.232.175.255254
177175.232.176.0/24175.232.176.1 to 175.232.176.254175.232.176.255254
178175.232.177.0/24175.232.177.1 to 175.232.177.254175.232.177.255254
179175.232.178.0/24175.232.178.1 to 175.232.178.254175.232.178.255254
180175.232.179.0/24175.232.179.1 to 175.232.179.254175.232.179.255254
181175.232.180.0/24175.232.180.1 to 175.232.180.254175.232.180.255254
182175.232.181.0/24175.232.181.1 to 175.232.181.254175.232.181.255254
183175.232.182.0/24175.232.182.1 to 175.232.182.254175.232.182.255254
184175.232.183.0/24175.232.183.1 to 175.232.183.254175.232.183.255254
185175.232.184.0/24175.232.184.1 to 175.232.184.254175.232.184.255254
186175.232.185.0/24175.232.185.1 to 175.232.185.254175.232.185.255254
187175.232.186.0/24175.232.186.1 to 175.232.186.254175.232.186.255254
188175.232.187.0/24175.232.187.1 to 175.232.187.254175.232.187.255254
189175.232.188.0/24175.232.188.1 to 175.232.188.254175.232.188.255254
190175.232.189.0/24175.232.189.1 to 175.232.189.254175.232.189.255254
191175.232.190.0/24175.232.190.1 to 175.232.190.254175.232.190.255254
192175.232.191.0/24175.232.191.1 to 175.232.191.254175.232.191.255254
193175.232.192.0/24175.232.192.1 to 175.232.192.254175.232.192.255254
194175.232.193.0/24175.232.193.1 to 175.232.193.254175.232.193.255254
195175.232.194.0/24175.232.194.1 to 175.232.194.254175.232.194.255254
196175.232.195.0/24175.232.195.1 to 175.232.195.254175.232.195.255254
197175.232.196.0/24175.232.196.1 to 175.232.196.254175.232.196.255254
198175.232.197.0/24175.232.197.1 to 175.232.197.254175.232.197.255254
199175.232.198.0/24175.232.198.1 to 175.232.198.254175.232.198.255254
200175.232.199.0/24175.232.199.1 to 175.232.199.254175.232.199.255254
201175.232.200.0/24175.232.200.1 to 175.232.200.254175.232.200.255254
202175.232.201.0/24175.232.201.1 to 175.232.201.254175.232.201.255254
203175.232.202.0/24175.232.202.1 to 175.232.202.254175.232.202.255254
204175.232.203.0/24175.232.203.1 to 175.232.203.254175.232.203.255254
205175.232.204.0/24175.232.204.1 to 175.232.204.254175.232.204.255254
206175.232.205.0/24175.232.205.1 to 175.232.205.254175.232.205.255254
207175.232.206.0/24175.232.206.1 to 175.232.206.254175.232.206.255254
208175.232.207.0/24175.232.207.1 to 175.232.207.254175.232.207.255254
209175.232.208.0/24175.232.208.1 to 175.232.208.254175.232.208.255254
210175.232.209.0/24175.232.209.1 to 175.232.209.254175.232.209.255254
211175.232.210.0/24175.232.210.1 to 175.232.210.254175.232.210.255254
212175.232.211.0/24175.232.211.1 to 175.232.211.254175.232.211.255254
213175.232.212.0/24175.232.212.1 to 175.232.212.254175.232.212.255254
214175.232.213.0/24175.232.213.1 to 175.232.213.254175.232.213.255254
215175.232.214.0/24175.232.214.1 to 175.232.214.254175.232.214.255254
216175.232.215.0/24175.232.215.1 to 175.232.215.254175.232.215.255254
217175.232.216.0/24175.232.216.1 to 175.232.216.254175.232.216.255254
218175.232.217.0/24175.232.217.1 to 175.232.217.254175.232.217.255254
219175.232.218.0/24175.232.218.1 to 175.232.218.254175.232.218.255254
220175.232.219.0/24175.232.219.1 to 175.232.219.254175.232.219.255254
221175.232.220.0/24175.232.220.1 to 175.232.220.254175.232.220.255254
222175.232.221.0/24175.232.221.1 to 175.232.221.254175.232.221.255254
223175.232.222.0/24175.232.222.1 to 175.232.222.254175.232.222.255254
224175.232.223.0/24175.232.223.1 to 175.232.223.254175.232.223.255254
225175.232.224.0/24175.232.224.1 to 175.232.224.254175.232.224.255254
226175.232.225.0/24175.232.225.1 to 175.232.225.254175.232.225.255254
227175.232.226.0/24175.232.226.1 to 175.232.226.254175.232.226.255254
228175.232.227.0/24175.232.227.1 to 175.232.227.254175.232.227.255254
229175.232.228.0/24175.232.228.1 to 175.232.228.254175.232.228.255254
230175.232.229.0/24175.232.229.1 to 175.232.229.254175.232.229.255254
231175.232.230.0/24175.232.230.1 to 175.232.230.254175.232.230.255254
232175.232.231.0/24175.232.231.1 to 175.232.231.254175.232.231.255254
233175.232.232.0/24175.232.232.1 to 175.232.232.254175.232.232.255254
234175.232.233.0/24175.232.233.1 to 175.232.233.254175.232.233.255254
235175.232.234.0/24175.232.234.1 to 175.232.234.254175.232.234.255254
236175.232.235.0/24175.232.235.1 to 175.232.235.254175.232.235.255254
237175.232.236.0/24175.232.236.1 to 175.232.236.254175.232.236.255254
238175.232.237.0/24175.232.237.1 to 175.232.237.254175.232.237.255254
239175.232.238.0/24175.232.238.1 to 175.232.238.254175.232.238.255254
240175.232.239.0/24175.232.239.1 to 175.232.239.254175.232.239.255254
241175.232.240.0/24175.232.240.1 to 175.232.240.254175.232.240.255254
242175.232.241.0/24175.232.241.1 to 175.232.241.254175.232.241.255254
243175.232.242.0/24175.232.242.1 to 175.232.242.254175.232.242.255254
244175.232.243.0/24175.232.243.1 to 175.232.243.254175.232.243.255254
245175.232.244.0/24175.232.244.1 to 175.232.244.254175.232.244.255254
246175.232.245.0/24175.232.245.1 to 175.232.245.254175.232.245.255254
247175.232.246.0/24175.232.246.1 to 175.232.246.254175.232.246.255254
248175.232.247.0/24175.232.247.1 to 175.232.247.254175.232.247.255254
249175.232.248.0/24175.232.248.1 to 175.232.248.254175.232.248.255254
250175.232.249.0/24175.232.249.1 to 175.232.249.254175.232.249.255254
251175.232.250.0/24175.232.250.1 to 175.232.250.254175.232.250.255254
252175.232.251.0/24175.232.251.1 to 175.232.251.254175.232.251.255254
253175.232.252.0/24175.232.252.1 to 175.232.252.254175.232.252.255254
254175.232.253.0/24175.232.253.1 to 175.232.253.254175.232.253.255254
255175.232.254.0/24175.232.254.1 to 175.232.254.254175.232.254.255254
256175.232.255.0/24175.232.255.1 to 175.232.255.254175.232.255.255254

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.