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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.

Network101.232.0.0/14
Usable hosts262,142
Subnet mask255.252.0.0
Addresses262,144
Network address
101.232.0.0
Broadcast address
101.235.255.255
First usable
101.232.0.1
Last usable
101.235.255.254
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
A (default /8)
As numbers
Hex 65E80000 · Integer 1709703168 to 1709965311
Reverse DNS zones
232.101.in-addr.arpa
233.101.in-addr.arpa
234.101.in-addr.arpa
235.101.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
Address01100101.11101000.00000000.00000000101.232.0.0
Subnet mask11111111.11111100.00000000.00000000255.252.0.0
Network01100101.11101000.00000000.00000000101.232.0.0
Broadcast01100101.11101011.11111111.11111111101.235.255.255
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)

101.232.0.0/14 makes 256 subnets of /22.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
1101.232.0.0/22101.232.0.1 to 101.232.3.254101.232.3.2551,022
2101.232.4.0/22101.232.4.1 to 101.232.7.254101.232.7.2551,022
3101.232.8.0/22101.232.8.1 to 101.232.11.254101.232.11.2551,022
4101.232.12.0/22101.232.12.1 to 101.232.15.254101.232.15.2551,022
5101.232.16.0/22101.232.16.1 to 101.232.19.254101.232.19.2551,022
6101.232.20.0/22101.232.20.1 to 101.232.23.254101.232.23.2551,022
7101.232.24.0/22101.232.24.1 to 101.232.27.254101.232.27.2551,022
8101.232.28.0/22101.232.28.1 to 101.232.31.254101.232.31.2551,022
9101.232.32.0/22101.232.32.1 to 101.232.35.254101.232.35.2551,022
10101.232.36.0/22101.232.36.1 to 101.232.39.254101.232.39.2551,022
11101.232.40.0/22101.232.40.1 to 101.232.43.254101.232.43.2551,022
12101.232.44.0/22101.232.44.1 to 101.232.47.254101.232.47.2551,022
13101.232.48.0/22101.232.48.1 to 101.232.51.254101.232.51.2551,022
14101.232.52.0/22101.232.52.1 to 101.232.55.254101.232.55.2551,022
15101.232.56.0/22101.232.56.1 to 101.232.59.254101.232.59.2551,022
16101.232.60.0/22101.232.60.1 to 101.232.63.254101.232.63.2551,022
17101.232.64.0/22101.232.64.1 to 101.232.67.254101.232.67.2551,022
18101.232.68.0/22101.232.68.1 to 101.232.71.254101.232.71.2551,022
19101.232.72.0/22101.232.72.1 to 101.232.75.254101.232.75.2551,022
20101.232.76.0/22101.232.76.1 to 101.232.79.254101.232.79.2551,022
21101.232.80.0/22101.232.80.1 to 101.232.83.254101.232.83.2551,022
22101.232.84.0/22101.232.84.1 to 101.232.87.254101.232.87.2551,022
23101.232.88.0/22101.232.88.1 to 101.232.91.254101.232.91.2551,022
24101.232.92.0/22101.232.92.1 to 101.232.95.254101.232.95.2551,022
25101.232.96.0/22101.232.96.1 to 101.232.99.254101.232.99.2551,022
26101.232.100.0/22101.232.100.1 to 101.232.103.254101.232.103.2551,022
27101.232.104.0/22101.232.104.1 to 101.232.107.254101.232.107.2551,022
28101.232.108.0/22101.232.108.1 to 101.232.111.254101.232.111.2551,022
29101.232.112.0/22101.232.112.1 to 101.232.115.254101.232.115.2551,022
30101.232.116.0/22101.232.116.1 to 101.232.119.254101.232.119.2551,022
31101.232.120.0/22101.232.120.1 to 101.232.123.254101.232.123.2551,022
32101.232.124.0/22101.232.124.1 to 101.232.127.254101.232.127.2551,022
33101.232.128.0/22101.232.128.1 to 101.232.131.254101.232.131.2551,022
34101.232.132.0/22101.232.132.1 to 101.232.135.254101.232.135.2551,022
35101.232.136.0/22101.232.136.1 to 101.232.139.254101.232.139.2551,022
36101.232.140.0/22101.232.140.1 to 101.232.143.254101.232.143.2551,022
37101.232.144.0/22101.232.144.1 to 101.232.147.254101.232.147.2551,022
38101.232.148.0/22101.232.148.1 to 101.232.151.254101.232.151.2551,022
39101.232.152.0/22101.232.152.1 to 101.232.155.254101.232.155.2551,022
40101.232.156.0/22101.232.156.1 to 101.232.159.254101.232.159.2551,022
41101.232.160.0/22101.232.160.1 to 101.232.163.254101.232.163.2551,022
42101.232.164.0/22101.232.164.1 to 101.232.167.254101.232.167.2551,022
43101.232.168.0/22101.232.168.1 to 101.232.171.254101.232.171.2551,022
44101.232.172.0/22101.232.172.1 to 101.232.175.254101.232.175.2551,022
45101.232.176.0/22101.232.176.1 to 101.232.179.254101.232.179.2551,022
46101.232.180.0/22101.232.180.1 to 101.232.183.254101.232.183.2551,022
47101.232.184.0/22101.232.184.1 to 101.232.187.254101.232.187.2551,022
48101.232.188.0/22101.232.188.1 to 101.232.191.254101.232.191.2551,022
49101.232.192.0/22101.232.192.1 to 101.232.195.254101.232.195.2551,022
50101.232.196.0/22101.232.196.1 to 101.232.199.254101.232.199.2551,022
51101.232.200.0/22101.232.200.1 to 101.232.203.254101.232.203.2551,022
52101.232.204.0/22101.232.204.1 to 101.232.207.254101.232.207.2551,022
53101.232.208.0/22101.232.208.1 to 101.232.211.254101.232.211.2551,022
54101.232.212.0/22101.232.212.1 to 101.232.215.254101.232.215.2551,022
55101.232.216.0/22101.232.216.1 to 101.232.219.254101.232.219.2551,022
56101.232.220.0/22101.232.220.1 to 101.232.223.254101.232.223.2551,022
57101.232.224.0/22101.232.224.1 to 101.232.227.254101.232.227.2551,022
58101.232.228.0/22101.232.228.1 to 101.232.231.254101.232.231.2551,022
59101.232.232.0/22101.232.232.1 to 101.232.235.254101.232.235.2551,022
60101.232.236.0/22101.232.236.1 to 101.232.239.254101.232.239.2551,022
61101.232.240.0/22101.232.240.1 to 101.232.243.254101.232.243.2551,022
62101.232.244.0/22101.232.244.1 to 101.232.247.254101.232.247.2551,022
63101.232.248.0/22101.232.248.1 to 101.232.251.254101.232.251.2551,022
64101.232.252.0/22101.232.252.1 to 101.232.255.254101.232.255.2551,022
65101.233.0.0/22101.233.0.1 to 101.233.3.254101.233.3.2551,022
66101.233.4.0/22101.233.4.1 to 101.233.7.254101.233.7.2551,022
67101.233.8.0/22101.233.8.1 to 101.233.11.254101.233.11.2551,022
68101.233.12.0/22101.233.12.1 to 101.233.15.254101.233.15.2551,022
69101.233.16.0/22101.233.16.1 to 101.233.19.254101.233.19.2551,022
70101.233.20.0/22101.233.20.1 to 101.233.23.254101.233.23.2551,022
71101.233.24.0/22101.233.24.1 to 101.233.27.254101.233.27.2551,022
72101.233.28.0/22101.233.28.1 to 101.233.31.254101.233.31.2551,022
73101.233.32.0/22101.233.32.1 to 101.233.35.254101.233.35.2551,022
74101.233.36.0/22101.233.36.1 to 101.233.39.254101.233.39.2551,022
75101.233.40.0/22101.233.40.1 to 101.233.43.254101.233.43.2551,022
76101.233.44.0/22101.233.44.1 to 101.233.47.254101.233.47.2551,022
77101.233.48.0/22101.233.48.1 to 101.233.51.254101.233.51.2551,022
78101.233.52.0/22101.233.52.1 to 101.233.55.254101.233.55.2551,022
79101.233.56.0/22101.233.56.1 to 101.233.59.254101.233.59.2551,022
80101.233.60.0/22101.233.60.1 to 101.233.63.254101.233.63.2551,022
81101.233.64.0/22101.233.64.1 to 101.233.67.254101.233.67.2551,022
82101.233.68.0/22101.233.68.1 to 101.233.71.254101.233.71.2551,022
83101.233.72.0/22101.233.72.1 to 101.233.75.254101.233.75.2551,022
84101.233.76.0/22101.233.76.1 to 101.233.79.254101.233.79.2551,022
85101.233.80.0/22101.233.80.1 to 101.233.83.254101.233.83.2551,022
86101.233.84.0/22101.233.84.1 to 101.233.87.254101.233.87.2551,022
87101.233.88.0/22101.233.88.1 to 101.233.91.254101.233.91.2551,022
88101.233.92.0/22101.233.92.1 to 101.233.95.254101.233.95.2551,022
89101.233.96.0/22101.233.96.1 to 101.233.99.254101.233.99.2551,022
90101.233.100.0/22101.233.100.1 to 101.233.103.254101.233.103.2551,022
91101.233.104.0/22101.233.104.1 to 101.233.107.254101.233.107.2551,022
92101.233.108.0/22101.233.108.1 to 101.233.111.254101.233.111.2551,022
93101.233.112.0/22101.233.112.1 to 101.233.115.254101.233.115.2551,022
94101.233.116.0/22101.233.116.1 to 101.233.119.254101.233.119.2551,022
95101.233.120.0/22101.233.120.1 to 101.233.123.254101.233.123.2551,022
96101.233.124.0/22101.233.124.1 to 101.233.127.254101.233.127.2551,022
97101.233.128.0/22101.233.128.1 to 101.233.131.254101.233.131.2551,022
98101.233.132.0/22101.233.132.1 to 101.233.135.254101.233.135.2551,022
99101.233.136.0/22101.233.136.1 to 101.233.139.254101.233.139.2551,022
100101.233.140.0/22101.233.140.1 to 101.233.143.254101.233.143.2551,022
101101.233.144.0/22101.233.144.1 to 101.233.147.254101.233.147.2551,022
102101.233.148.0/22101.233.148.1 to 101.233.151.254101.233.151.2551,022
103101.233.152.0/22101.233.152.1 to 101.233.155.254101.233.155.2551,022
104101.233.156.0/22101.233.156.1 to 101.233.159.254101.233.159.2551,022
105101.233.160.0/22101.233.160.1 to 101.233.163.254101.233.163.2551,022
106101.233.164.0/22101.233.164.1 to 101.233.167.254101.233.167.2551,022
107101.233.168.0/22101.233.168.1 to 101.233.171.254101.233.171.2551,022
108101.233.172.0/22101.233.172.1 to 101.233.175.254101.233.175.2551,022
109101.233.176.0/22101.233.176.1 to 101.233.179.254101.233.179.2551,022
110101.233.180.0/22101.233.180.1 to 101.233.183.254101.233.183.2551,022
111101.233.184.0/22101.233.184.1 to 101.233.187.254101.233.187.2551,022
112101.233.188.0/22101.233.188.1 to 101.233.191.254101.233.191.2551,022
113101.233.192.0/22101.233.192.1 to 101.233.195.254101.233.195.2551,022
114101.233.196.0/22101.233.196.1 to 101.233.199.254101.233.199.2551,022
115101.233.200.0/22101.233.200.1 to 101.233.203.254101.233.203.2551,022
116101.233.204.0/22101.233.204.1 to 101.233.207.254101.233.207.2551,022
117101.233.208.0/22101.233.208.1 to 101.233.211.254101.233.211.2551,022
118101.233.212.0/22101.233.212.1 to 101.233.215.254101.233.215.2551,022
119101.233.216.0/22101.233.216.1 to 101.233.219.254101.233.219.2551,022
120101.233.220.0/22101.233.220.1 to 101.233.223.254101.233.223.2551,022
121101.233.224.0/22101.233.224.1 to 101.233.227.254101.233.227.2551,022
122101.233.228.0/22101.233.228.1 to 101.233.231.254101.233.231.2551,022
123101.233.232.0/22101.233.232.1 to 101.233.235.254101.233.235.2551,022
124101.233.236.0/22101.233.236.1 to 101.233.239.254101.233.239.2551,022
125101.233.240.0/22101.233.240.1 to 101.233.243.254101.233.243.2551,022
126101.233.244.0/22101.233.244.1 to 101.233.247.254101.233.247.2551,022
127101.233.248.0/22101.233.248.1 to 101.233.251.254101.233.251.2551,022
128101.233.252.0/22101.233.252.1 to 101.233.255.254101.233.255.2551,022
129101.234.0.0/22101.234.0.1 to 101.234.3.254101.234.3.2551,022
130101.234.4.0/22101.234.4.1 to 101.234.7.254101.234.7.2551,022
131101.234.8.0/22101.234.8.1 to 101.234.11.254101.234.11.2551,022
132101.234.12.0/22101.234.12.1 to 101.234.15.254101.234.15.2551,022
133101.234.16.0/22101.234.16.1 to 101.234.19.254101.234.19.2551,022
134101.234.20.0/22101.234.20.1 to 101.234.23.254101.234.23.2551,022
135101.234.24.0/22101.234.24.1 to 101.234.27.254101.234.27.2551,022
136101.234.28.0/22101.234.28.1 to 101.234.31.254101.234.31.2551,022
137101.234.32.0/22101.234.32.1 to 101.234.35.254101.234.35.2551,022
138101.234.36.0/22101.234.36.1 to 101.234.39.254101.234.39.2551,022
139101.234.40.0/22101.234.40.1 to 101.234.43.254101.234.43.2551,022
140101.234.44.0/22101.234.44.1 to 101.234.47.254101.234.47.2551,022
141101.234.48.0/22101.234.48.1 to 101.234.51.254101.234.51.2551,022
142101.234.52.0/22101.234.52.1 to 101.234.55.254101.234.55.2551,022
143101.234.56.0/22101.234.56.1 to 101.234.59.254101.234.59.2551,022
144101.234.60.0/22101.234.60.1 to 101.234.63.254101.234.63.2551,022
145101.234.64.0/22101.234.64.1 to 101.234.67.254101.234.67.2551,022
146101.234.68.0/22101.234.68.1 to 101.234.71.254101.234.71.2551,022
147101.234.72.0/22101.234.72.1 to 101.234.75.254101.234.75.2551,022
148101.234.76.0/22101.234.76.1 to 101.234.79.254101.234.79.2551,022
149101.234.80.0/22101.234.80.1 to 101.234.83.254101.234.83.2551,022
150101.234.84.0/22101.234.84.1 to 101.234.87.254101.234.87.2551,022
151101.234.88.0/22101.234.88.1 to 101.234.91.254101.234.91.2551,022
152101.234.92.0/22101.234.92.1 to 101.234.95.254101.234.95.2551,022
153101.234.96.0/22101.234.96.1 to 101.234.99.254101.234.99.2551,022
154101.234.100.0/22101.234.100.1 to 101.234.103.254101.234.103.2551,022
155101.234.104.0/22101.234.104.1 to 101.234.107.254101.234.107.2551,022
156101.234.108.0/22101.234.108.1 to 101.234.111.254101.234.111.2551,022
157101.234.112.0/22101.234.112.1 to 101.234.115.254101.234.115.2551,022
158101.234.116.0/22101.234.116.1 to 101.234.119.254101.234.119.2551,022
159101.234.120.0/22101.234.120.1 to 101.234.123.254101.234.123.2551,022
160101.234.124.0/22101.234.124.1 to 101.234.127.254101.234.127.2551,022
161101.234.128.0/22101.234.128.1 to 101.234.131.254101.234.131.2551,022
162101.234.132.0/22101.234.132.1 to 101.234.135.254101.234.135.2551,022
163101.234.136.0/22101.234.136.1 to 101.234.139.254101.234.139.2551,022
164101.234.140.0/22101.234.140.1 to 101.234.143.254101.234.143.2551,022
165101.234.144.0/22101.234.144.1 to 101.234.147.254101.234.147.2551,022
166101.234.148.0/22101.234.148.1 to 101.234.151.254101.234.151.2551,022
167101.234.152.0/22101.234.152.1 to 101.234.155.254101.234.155.2551,022
168101.234.156.0/22101.234.156.1 to 101.234.159.254101.234.159.2551,022
169101.234.160.0/22101.234.160.1 to 101.234.163.254101.234.163.2551,022
170101.234.164.0/22101.234.164.1 to 101.234.167.254101.234.167.2551,022
171101.234.168.0/22101.234.168.1 to 101.234.171.254101.234.171.2551,022
172101.234.172.0/22101.234.172.1 to 101.234.175.254101.234.175.2551,022
173101.234.176.0/22101.234.176.1 to 101.234.179.254101.234.179.2551,022
174101.234.180.0/22101.234.180.1 to 101.234.183.254101.234.183.2551,022
175101.234.184.0/22101.234.184.1 to 101.234.187.254101.234.187.2551,022
176101.234.188.0/22101.234.188.1 to 101.234.191.254101.234.191.2551,022
177101.234.192.0/22101.234.192.1 to 101.234.195.254101.234.195.2551,022
178101.234.196.0/22101.234.196.1 to 101.234.199.254101.234.199.2551,022
179101.234.200.0/22101.234.200.1 to 101.234.203.254101.234.203.2551,022
180101.234.204.0/22101.234.204.1 to 101.234.207.254101.234.207.2551,022
181101.234.208.0/22101.234.208.1 to 101.234.211.254101.234.211.2551,022
182101.234.212.0/22101.234.212.1 to 101.234.215.254101.234.215.2551,022
183101.234.216.0/22101.234.216.1 to 101.234.219.254101.234.219.2551,022
184101.234.220.0/22101.234.220.1 to 101.234.223.254101.234.223.2551,022
185101.234.224.0/22101.234.224.1 to 101.234.227.254101.234.227.2551,022
186101.234.228.0/22101.234.228.1 to 101.234.231.254101.234.231.2551,022
187101.234.232.0/22101.234.232.1 to 101.234.235.254101.234.235.2551,022
188101.234.236.0/22101.234.236.1 to 101.234.239.254101.234.239.2551,022
189101.234.240.0/22101.234.240.1 to 101.234.243.254101.234.243.2551,022
190101.234.244.0/22101.234.244.1 to 101.234.247.254101.234.247.2551,022
191101.234.248.0/22101.234.248.1 to 101.234.251.254101.234.251.2551,022
192101.234.252.0/22101.234.252.1 to 101.234.255.254101.234.255.2551,022
193101.235.0.0/22101.235.0.1 to 101.235.3.254101.235.3.2551,022
194101.235.4.0/22101.235.4.1 to 101.235.7.254101.235.7.2551,022
195101.235.8.0/22101.235.8.1 to 101.235.11.254101.235.11.2551,022
196101.235.12.0/22101.235.12.1 to 101.235.15.254101.235.15.2551,022
197101.235.16.0/22101.235.16.1 to 101.235.19.254101.235.19.2551,022
198101.235.20.0/22101.235.20.1 to 101.235.23.254101.235.23.2551,022
199101.235.24.0/22101.235.24.1 to 101.235.27.254101.235.27.2551,022
200101.235.28.0/22101.235.28.1 to 101.235.31.254101.235.31.2551,022
201101.235.32.0/22101.235.32.1 to 101.235.35.254101.235.35.2551,022
202101.235.36.0/22101.235.36.1 to 101.235.39.254101.235.39.2551,022
203101.235.40.0/22101.235.40.1 to 101.235.43.254101.235.43.2551,022
204101.235.44.0/22101.235.44.1 to 101.235.47.254101.235.47.2551,022
205101.235.48.0/22101.235.48.1 to 101.235.51.254101.235.51.2551,022
206101.235.52.0/22101.235.52.1 to 101.235.55.254101.235.55.2551,022
207101.235.56.0/22101.235.56.1 to 101.235.59.254101.235.59.2551,022
208101.235.60.0/22101.235.60.1 to 101.235.63.254101.235.63.2551,022
209101.235.64.0/22101.235.64.1 to 101.235.67.254101.235.67.2551,022
210101.235.68.0/22101.235.68.1 to 101.235.71.254101.235.71.2551,022
211101.235.72.0/22101.235.72.1 to 101.235.75.254101.235.75.2551,022
212101.235.76.0/22101.235.76.1 to 101.235.79.254101.235.79.2551,022
213101.235.80.0/22101.235.80.1 to 101.235.83.254101.235.83.2551,022
214101.235.84.0/22101.235.84.1 to 101.235.87.254101.235.87.2551,022
215101.235.88.0/22101.235.88.1 to 101.235.91.254101.235.91.2551,022
216101.235.92.0/22101.235.92.1 to 101.235.95.254101.235.95.2551,022
217101.235.96.0/22101.235.96.1 to 101.235.99.254101.235.99.2551,022
218101.235.100.0/22101.235.100.1 to 101.235.103.254101.235.103.2551,022
219101.235.104.0/22101.235.104.1 to 101.235.107.254101.235.107.2551,022
220101.235.108.0/22101.235.108.1 to 101.235.111.254101.235.111.2551,022
221101.235.112.0/22101.235.112.1 to 101.235.115.254101.235.115.2551,022
222101.235.116.0/22101.235.116.1 to 101.235.119.254101.235.119.2551,022
223101.235.120.0/22101.235.120.1 to 101.235.123.254101.235.123.2551,022
224101.235.124.0/22101.235.124.1 to 101.235.127.254101.235.127.2551,022
225101.235.128.0/22101.235.128.1 to 101.235.131.254101.235.131.2551,022
226101.235.132.0/22101.235.132.1 to 101.235.135.254101.235.135.2551,022
227101.235.136.0/22101.235.136.1 to 101.235.139.254101.235.139.2551,022
228101.235.140.0/22101.235.140.1 to 101.235.143.254101.235.143.2551,022
229101.235.144.0/22101.235.144.1 to 101.235.147.254101.235.147.2551,022
230101.235.148.0/22101.235.148.1 to 101.235.151.254101.235.151.2551,022
231101.235.152.0/22101.235.152.1 to 101.235.155.254101.235.155.2551,022
232101.235.156.0/22101.235.156.1 to 101.235.159.254101.235.159.2551,022
233101.235.160.0/22101.235.160.1 to 101.235.163.254101.235.163.2551,022
234101.235.164.0/22101.235.164.1 to 101.235.167.254101.235.167.2551,022
235101.235.168.0/22101.235.168.1 to 101.235.171.254101.235.171.2551,022
236101.235.172.0/22101.235.172.1 to 101.235.175.254101.235.175.2551,022
237101.235.176.0/22101.235.176.1 to 101.235.179.254101.235.179.2551,022
238101.235.180.0/22101.235.180.1 to 101.235.183.254101.235.183.2551,022
239101.235.184.0/22101.235.184.1 to 101.235.187.254101.235.187.2551,022
240101.235.188.0/22101.235.188.1 to 101.235.191.254101.235.191.2551,022
241101.235.192.0/22101.235.192.1 to 101.235.195.254101.235.195.2551,022
242101.235.196.0/22101.235.196.1 to 101.235.199.254101.235.199.2551,022
243101.235.200.0/22101.235.200.1 to 101.235.203.254101.235.203.2551,022
244101.235.204.0/22101.235.204.1 to 101.235.207.254101.235.207.2551,022
245101.235.208.0/22101.235.208.1 to 101.235.211.254101.235.211.2551,022
246101.235.212.0/22101.235.212.1 to 101.235.215.254101.235.215.2551,022
247101.235.216.0/22101.235.216.1 to 101.235.219.254101.235.219.2551,022
248101.235.220.0/22101.235.220.1 to 101.235.223.254101.235.223.2551,022
249101.235.224.0/22101.235.224.1 to 101.235.227.254101.235.227.2551,022
250101.235.228.0/22101.235.228.1 to 101.235.231.254101.235.231.2551,022
251101.235.232.0/22101.235.232.1 to 101.235.235.254101.235.235.2551,022
252101.235.236.0/22101.235.236.1 to 101.235.239.254101.235.239.2551,022
253101.235.240.0/22101.235.240.1 to 101.235.243.254101.235.243.2551,022
254101.235.244.0/22101.235.244.1 to 101.235.247.254101.235.247.2551,022
255101.235.248.0/22101.235.248.1 to 101.235.251.254101.235.251.2551,022
256101.235.252.0/22101.235.252.1 to 101.235.255.254101.235.255.2551,022

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.