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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.

Network204.232.0.0/14
Usable hosts262,142
Subnet mask255.252.0.0
Addresses262,144
Network address
204.232.0.0
Broadcast address
204.235.255.255
First usable
204.232.0.1
Last usable
204.235.255.254
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
C (default /24)
As numbers
Hex CCE80000 · Integer 3437756416 to 3438018559
Reverse DNS zones
232.204.in-addr.arpa
233.204.in-addr.arpa
234.204.in-addr.arpa
235.204.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
Address11001100.11101000.00000000.00000000204.232.0.0
Subnet mask11111111.11111100.00000000.00000000255.252.0.0
Network11001100.11101000.00000000.00000000204.232.0.0
Broadcast11001100.11101011.11111111.11111111204.235.255.255
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)

204.232.0.0/14 makes 256 subnets of /22.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
1204.232.0.0/22204.232.0.1 to 204.232.3.254204.232.3.2551,022
2204.232.4.0/22204.232.4.1 to 204.232.7.254204.232.7.2551,022
3204.232.8.0/22204.232.8.1 to 204.232.11.254204.232.11.2551,022
4204.232.12.0/22204.232.12.1 to 204.232.15.254204.232.15.2551,022
5204.232.16.0/22204.232.16.1 to 204.232.19.254204.232.19.2551,022
6204.232.20.0/22204.232.20.1 to 204.232.23.254204.232.23.2551,022
7204.232.24.0/22204.232.24.1 to 204.232.27.254204.232.27.2551,022
8204.232.28.0/22204.232.28.1 to 204.232.31.254204.232.31.2551,022
9204.232.32.0/22204.232.32.1 to 204.232.35.254204.232.35.2551,022
10204.232.36.0/22204.232.36.1 to 204.232.39.254204.232.39.2551,022
11204.232.40.0/22204.232.40.1 to 204.232.43.254204.232.43.2551,022
12204.232.44.0/22204.232.44.1 to 204.232.47.254204.232.47.2551,022
13204.232.48.0/22204.232.48.1 to 204.232.51.254204.232.51.2551,022
14204.232.52.0/22204.232.52.1 to 204.232.55.254204.232.55.2551,022
15204.232.56.0/22204.232.56.1 to 204.232.59.254204.232.59.2551,022
16204.232.60.0/22204.232.60.1 to 204.232.63.254204.232.63.2551,022
17204.232.64.0/22204.232.64.1 to 204.232.67.254204.232.67.2551,022
18204.232.68.0/22204.232.68.1 to 204.232.71.254204.232.71.2551,022
19204.232.72.0/22204.232.72.1 to 204.232.75.254204.232.75.2551,022
20204.232.76.0/22204.232.76.1 to 204.232.79.254204.232.79.2551,022
21204.232.80.0/22204.232.80.1 to 204.232.83.254204.232.83.2551,022
22204.232.84.0/22204.232.84.1 to 204.232.87.254204.232.87.2551,022
23204.232.88.0/22204.232.88.1 to 204.232.91.254204.232.91.2551,022
24204.232.92.0/22204.232.92.1 to 204.232.95.254204.232.95.2551,022
25204.232.96.0/22204.232.96.1 to 204.232.99.254204.232.99.2551,022
26204.232.100.0/22204.232.100.1 to 204.232.103.254204.232.103.2551,022
27204.232.104.0/22204.232.104.1 to 204.232.107.254204.232.107.2551,022
28204.232.108.0/22204.232.108.1 to 204.232.111.254204.232.111.2551,022
29204.232.112.0/22204.232.112.1 to 204.232.115.254204.232.115.2551,022
30204.232.116.0/22204.232.116.1 to 204.232.119.254204.232.119.2551,022
31204.232.120.0/22204.232.120.1 to 204.232.123.254204.232.123.2551,022
32204.232.124.0/22204.232.124.1 to 204.232.127.254204.232.127.2551,022
33204.232.128.0/22204.232.128.1 to 204.232.131.254204.232.131.2551,022
34204.232.132.0/22204.232.132.1 to 204.232.135.254204.232.135.2551,022
35204.232.136.0/22204.232.136.1 to 204.232.139.254204.232.139.2551,022
36204.232.140.0/22204.232.140.1 to 204.232.143.254204.232.143.2551,022
37204.232.144.0/22204.232.144.1 to 204.232.147.254204.232.147.2551,022
38204.232.148.0/22204.232.148.1 to 204.232.151.254204.232.151.2551,022
39204.232.152.0/22204.232.152.1 to 204.232.155.254204.232.155.2551,022
40204.232.156.0/22204.232.156.1 to 204.232.159.254204.232.159.2551,022
41204.232.160.0/22204.232.160.1 to 204.232.163.254204.232.163.2551,022
42204.232.164.0/22204.232.164.1 to 204.232.167.254204.232.167.2551,022
43204.232.168.0/22204.232.168.1 to 204.232.171.254204.232.171.2551,022
44204.232.172.0/22204.232.172.1 to 204.232.175.254204.232.175.2551,022
45204.232.176.0/22204.232.176.1 to 204.232.179.254204.232.179.2551,022
46204.232.180.0/22204.232.180.1 to 204.232.183.254204.232.183.2551,022
47204.232.184.0/22204.232.184.1 to 204.232.187.254204.232.187.2551,022
48204.232.188.0/22204.232.188.1 to 204.232.191.254204.232.191.2551,022
49204.232.192.0/22204.232.192.1 to 204.232.195.254204.232.195.2551,022
50204.232.196.0/22204.232.196.1 to 204.232.199.254204.232.199.2551,022
51204.232.200.0/22204.232.200.1 to 204.232.203.254204.232.203.2551,022
52204.232.204.0/22204.232.204.1 to 204.232.207.254204.232.207.2551,022
53204.232.208.0/22204.232.208.1 to 204.232.211.254204.232.211.2551,022
54204.232.212.0/22204.232.212.1 to 204.232.215.254204.232.215.2551,022
55204.232.216.0/22204.232.216.1 to 204.232.219.254204.232.219.2551,022
56204.232.220.0/22204.232.220.1 to 204.232.223.254204.232.223.2551,022
57204.232.224.0/22204.232.224.1 to 204.232.227.254204.232.227.2551,022
58204.232.228.0/22204.232.228.1 to 204.232.231.254204.232.231.2551,022
59204.232.232.0/22204.232.232.1 to 204.232.235.254204.232.235.2551,022
60204.232.236.0/22204.232.236.1 to 204.232.239.254204.232.239.2551,022
61204.232.240.0/22204.232.240.1 to 204.232.243.254204.232.243.2551,022
62204.232.244.0/22204.232.244.1 to 204.232.247.254204.232.247.2551,022
63204.232.248.0/22204.232.248.1 to 204.232.251.254204.232.251.2551,022
64204.232.252.0/22204.232.252.1 to 204.232.255.254204.232.255.2551,022
65204.233.0.0/22204.233.0.1 to 204.233.3.254204.233.3.2551,022
66204.233.4.0/22204.233.4.1 to 204.233.7.254204.233.7.2551,022
67204.233.8.0/22204.233.8.1 to 204.233.11.254204.233.11.2551,022
68204.233.12.0/22204.233.12.1 to 204.233.15.254204.233.15.2551,022
69204.233.16.0/22204.233.16.1 to 204.233.19.254204.233.19.2551,022
70204.233.20.0/22204.233.20.1 to 204.233.23.254204.233.23.2551,022
71204.233.24.0/22204.233.24.1 to 204.233.27.254204.233.27.2551,022
72204.233.28.0/22204.233.28.1 to 204.233.31.254204.233.31.2551,022
73204.233.32.0/22204.233.32.1 to 204.233.35.254204.233.35.2551,022
74204.233.36.0/22204.233.36.1 to 204.233.39.254204.233.39.2551,022
75204.233.40.0/22204.233.40.1 to 204.233.43.254204.233.43.2551,022
76204.233.44.0/22204.233.44.1 to 204.233.47.254204.233.47.2551,022
77204.233.48.0/22204.233.48.1 to 204.233.51.254204.233.51.2551,022
78204.233.52.0/22204.233.52.1 to 204.233.55.254204.233.55.2551,022
79204.233.56.0/22204.233.56.1 to 204.233.59.254204.233.59.2551,022
80204.233.60.0/22204.233.60.1 to 204.233.63.254204.233.63.2551,022
81204.233.64.0/22204.233.64.1 to 204.233.67.254204.233.67.2551,022
82204.233.68.0/22204.233.68.1 to 204.233.71.254204.233.71.2551,022
83204.233.72.0/22204.233.72.1 to 204.233.75.254204.233.75.2551,022
84204.233.76.0/22204.233.76.1 to 204.233.79.254204.233.79.2551,022
85204.233.80.0/22204.233.80.1 to 204.233.83.254204.233.83.2551,022
86204.233.84.0/22204.233.84.1 to 204.233.87.254204.233.87.2551,022
87204.233.88.0/22204.233.88.1 to 204.233.91.254204.233.91.2551,022
88204.233.92.0/22204.233.92.1 to 204.233.95.254204.233.95.2551,022
89204.233.96.0/22204.233.96.1 to 204.233.99.254204.233.99.2551,022
90204.233.100.0/22204.233.100.1 to 204.233.103.254204.233.103.2551,022
91204.233.104.0/22204.233.104.1 to 204.233.107.254204.233.107.2551,022
92204.233.108.0/22204.233.108.1 to 204.233.111.254204.233.111.2551,022
93204.233.112.0/22204.233.112.1 to 204.233.115.254204.233.115.2551,022
94204.233.116.0/22204.233.116.1 to 204.233.119.254204.233.119.2551,022
95204.233.120.0/22204.233.120.1 to 204.233.123.254204.233.123.2551,022
96204.233.124.0/22204.233.124.1 to 204.233.127.254204.233.127.2551,022
97204.233.128.0/22204.233.128.1 to 204.233.131.254204.233.131.2551,022
98204.233.132.0/22204.233.132.1 to 204.233.135.254204.233.135.2551,022
99204.233.136.0/22204.233.136.1 to 204.233.139.254204.233.139.2551,022
100204.233.140.0/22204.233.140.1 to 204.233.143.254204.233.143.2551,022
101204.233.144.0/22204.233.144.1 to 204.233.147.254204.233.147.2551,022
102204.233.148.0/22204.233.148.1 to 204.233.151.254204.233.151.2551,022
103204.233.152.0/22204.233.152.1 to 204.233.155.254204.233.155.2551,022
104204.233.156.0/22204.233.156.1 to 204.233.159.254204.233.159.2551,022
105204.233.160.0/22204.233.160.1 to 204.233.163.254204.233.163.2551,022
106204.233.164.0/22204.233.164.1 to 204.233.167.254204.233.167.2551,022
107204.233.168.0/22204.233.168.1 to 204.233.171.254204.233.171.2551,022
108204.233.172.0/22204.233.172.1 to 204.233.175.254204.233.175.2551,022
109204.233.176.0/22204.233.176.1 to 204.233.179.254204.233.179.2551,022
110204.233.180.0/22204.233.180.1 to 204.233.183.254204.233.183.2551,022
111204.233.184.0/22204.233.184.1 to 204.233.187.254204.233.187.2551,022
112204.233.188.0/22204.233.188.1 to 204.233.191.254204.233.191.2551,022
113204.233.192.0/22204.233.192.1 to 204.233.195.254204.233.195.2551,022
114204.233.196.0/22204.233.196.1 to 204.233.199.254204.233.199.2551,022
115204.233.200.0/22204.233.200.1 to 204.233.203.254204.233.203.2551,022
116204.233.204.0/22204.233.204.1 to 204.233.207.254204.233.207.2551,022
117204.233.208.0/22204.233.208.1 to 204.233.211.254204.233.211.2551,022
118204.233.212.0/22204.233.212.1 to 204.233.215.254204.233.215.2551,022
119204.233.216.0/22204.233.216.1 to 204.233.219.254204.233.219.2551,022
120204.233.220.0/22204.233.220.1 to 204.233.223.254204.233.223.2551,022
121204.233.224.0/22204.233.224.1 to 204.233.227.254204.233.227.2551,022
122204.233.228.0/22204.233.228.1 to 204.233.231.254204.233.231.2551,022
123204.233.232.0/22204.233.232.1 to 204.233.235.254204.233.235.2551,022
124204.233.236.0/22204.233.236.1 to 204.233.239.254204.233.239.2551,022
125204.233.240.0/22204.233.240.1 to 204.233.243.254204.233.243.2551,022
126204.233.244.0/22204.233.244.1 to 204.233.247.254204.233.247.2551,022
127204.233.248.0/22204.233.248.1 to 204.233.251.254204.233.251.2551,022
128204.233.252.0/22204.233.252.1 to 204.233.255.254204.233.255.2551,022
129204.234.0.0/22204.234.0.1 to 204.234.3.254204.234.3.2551,022
130204.234.4.0/22204.234.4.1 to 204.234.7.254204.234.7.2551,022
131204.234.8.0/22204.234.8.1 to 204.234.11.254204.234.11.2551,022
132204.234.12.0/22204.234.12.1 to 204.234.15.254204.234.15.2551,022
133204.234.16.0/22204.234.16.1 to 204.234.19.254204.234.19.2551,022
134204.234.20.0/22204.234.20.1 to 204.234.23.254204.234.23.2551,022
135204.234.24.0/22204.234.24.1 to 204.234.27.254204.234.27.2551,022
136204.234.28.0/22204.234.28.1 to 204.234.31.254204.234.31.2551,022
137204.234.32.0/22204.234.32.1 to 204.234.35.254204.234.35.2551,022
138204.234.36.0/22204.234.36.1 to 204.234.39.254204.234.39.2551,022
139204.234.40.0/22204.234.40.1 to 204.234.43.254204.234.43.2551,022
140204.234.44.0/22204.234.44.1 to 204.234.47.254204.234.47.2551,022
141204.234.48.0/22204.234.48.1 to 204.234.51.254204.234.51.2551,022
142204.234.52.0/22204.234.52.1 to 204.234.55.254204.234.55.2551,022
143204.234.56.0/22204.234.56.1 to 204.234.59.254204.234.59.2551,022
144204.234.60.0/22204.234.60.1 to 204.234.63.254204.234.63.2551,022
145204.234.64.0/22204.234.64.1 to 204.234.67.254204.234.67.2551,022
146204.234.68.0/22204.234.68.1 to 204.234.71.254204.234.71.2551,022
147204.234.72.0/22204.234.72.1 to 204.234.75.254204.234.75.2551,022
148204.234.76.0/22204.234.76.1 to 204.234.79.254204.234.79.2551,022
149204.234.80.0/22204.234.80.1 to 204.234.83.254204.234.83.2551,022
150204.234.84.0/22204.234.84.1 to 204.234.87.254204.234.87.2551,022
151204.234.88.0/22204.234.88.1 to 204.234.91.254204.234.91.2551,022
152204.234.92.0/22204.234.92.1 to 204.234.95.254204.234.95.2551,022
153204.234.96.0/22204.234.96.1 to 204.234.99.254204.234.99.2551,022
154204.234.100.0/22204.234.100.1 to 204.234.103.254204.234.103.2551,022
155204.234.104.0/22204.234.104.1 to 204.234.107.254204.234.107.2551,022
156204.234.108.0/22204.234.108.1 to 204.234.111.254204.234.111.2551,022
157204.234.112.0/22204.234.112.1 to 204.234.115.254204.234.115.2551,022
158204.234.116.0/22204.234.116.1 to 204.234.119.254204.234.119.2551,022
159204.234.120.0/22204.234.120.1 to 204.234.123.254204.234.123.2551,022
160204.234.124.0/22204.234.124.1 to 204.234.127.254204.234.127.2551,022
161204.234.128.0/22204.234.128.1 to 204.234.131.254204.234.131.2551,022
162204.234.132.0/22204.234.132.1 to 204.234.135.254204.234.135.2551,022
163204.234.136.0/22204.234.136.1 to 204.234.139.254204.234.139.2551,022
164204.234.140.0/22204.234.140.1 to 204.234.143.254204.234.143.2551,022
165204.234.144.0/22204.234.144.1 to 204.234.147.254204.234.147.2551,022
166204.234.148.0/22204.234.148.1 to 204.234.151.254204.234.151.2551,022
167204.234.152.0/22204.234.152.1 to 204.234.155.254204.234.155.2551,022
168204.234.156.0/22204.234.156.1 to 204.234.159.254204.234.159.2551,022
169204.234.160.0/22204.234.160.1 to 204.234.163.254204.234.163.2551,022
170204.234.164.0/22204.234.164.1 to 204.234.167.254204.234.167.2551,022
171204.234.168.0/22204.234.168.1 to 204.234.171.254204.234.171.2551,022
172204.234.172.0/22204.234.172.1 to 204.234.175.254204.234.175.2551,022
173204.234.176.0/22204.234.176.1 to 204.234.179.254204.234.179.2551,022
174204.234.180.0/22204.234.180.1 to 204.234.183.254204.234.183.2551,022
175204.234.184.0/22204.234.184.1 to 204.234.187.254204.234.187.2551,022
176204.234.188.0/22204.234.188.1 to 204.234.191.254204.234.191.2551,022
177204.234.192.0/22204.234.192.1 to 204.234.195.254204.234.195.2551,022
178204.234.196.0/22204.234.196.1 to 204.234.199.254204.234.199.2551,022
179204.234.200.0/22204.234.200.1 to 204.234.203.254204.234.203.2551,022
180204.234.204.0/22204.234.204.1 to 204.234.207.254204.234.207.2551,022
181204.234.208.0/22204.234.208.1 to 204.234.211.254204.234.211.2551,022
182204.234.212.0/22204.234.212.1 to 204.234.215.254204.234.215.2551,022
183204.234.216.0/22204.234.216.1 to 204.234.219.254204.234.219.2551,022
184204.234.220.0/22204.234.220.1 to 204.234.223.254204.234.223.2551,022
185204.234.224.0/22204.234.224.1 to 204.234.227.254204.234.227.2551,022
186204.234.228.0/22204.234.228.1 to 204.234.231.254204.234.231.2551,022
187204.234.232.0/22204.234.232.1 to 204.234.235.254204.234.235.2551,022
188204.234.236.0/22204.234.236.1 to 204.234.239.254204.234.239.2551,022
189204.234.240.0/22204.234.240.1 to 204.234.243.254204.234.243.2551,022
190204.234.244.0/22204.234.244.1 to 204.234.247.254204.234.247.2551,022
191204.234.248.0/22204.234.248.1 to 204.234.251.254204.234.251.2551,022
192204.234.252.0/22204.234.252.1 to 204.234.255.254204.234.255.2551,022
193204.235.0.0/22204.235.0.1 to 204.235.3.254204.235.3.2551,022
194204.235.4.0/22204.235.4.1 to 204.235.7.254204.235.7.2551,022
195204.235.8.0/22204.235.8.1 to 204.235.11.254204.235.11.2551,022
196204.235.12.0/22204.235.12.1 to 204.235.15.254204.235.15.2551,022
197204.235.16.0/22204.235.16.1 to 204.235.19.254204.235.19.2551,022
198204.235.20.0/22204.235.20.1 to 204.235.23.254204.235.23.2551,022
199204.235.24.0/22204.235.24.1 to 204.235.27.254204.235.27.2551,022
200204.235.28.0/22204.235.28.1 to 204.235.31.254204.235.31.2551,022
201204.235.32.0/22204.235.32.1 to 204.235.35.254204.235.35.2551,022
202204.235.36.0/22204.235.36.1 to 204.235.39.254204.235.39.2551,022
203204.235.40.0/22204.235.40.1 to 204.235.43.254204.235.43.2551,022
204204.235.44.0/22204.235.44.1 to 204.235.47.254204.235.47.2551,022
205204.235.48.0/22204.235.48.1 to 204.235.51.254204.235.51.2551,022
206204.235.52.0/22204.235.52.1 to 204.235.55.254204.235.55.2551,022
207204.235.56.0/22204.235.56.1 to 204.235.59.254204.235.59.2551,022
208204.235.60.0/22204.235.60.1 to 204.235.63.254204.235.63.2551,022
209204.235.64.0/22204.235.64.1 to 204.235.67.254204.235.67.2551,022
210204.235.68.0/22204.235.68.1 to 204.235.71.254204.235.71.2551,022
211204.235.72.0/22204.235.72.1 to 204.235.75.254204.235.75.2551,022
212204.235.76.0/22204.235.76.1 to 204.235.79.254204.235.79.2551,022
213204.235.80.0/22204.235.80.1 to 204.235.83.254204.235.83.2551,022
214204.235.84.0/22204.235.84.1 to 204.235.87.254204.235.87.2551,022
215204.235.88.0/22204.235.88.1 to 204.235.91.254204.235.91.2551,022
216204.235.92.0/22204.235.92.1 to 204.235.95.254204.235.95.2551,022
217204.235.96.0/22204.235.96.1 to 204.235.99.254204.235.99.2551,022
218204.235.100.0/22204.235.100.1 to 204.235.103.254204.235.103.2551,022
219204.235.104.0/22204.235.104.1 to 204.235.107.254204.235.107.2551,022
220204.235.108.0/22204.235.108.1 to 204.235.111.254204.235.111.2551,022
221204.235.112.0/22204.235.112.1 to 204.235.115.254204.235.115.2551,022
222204.235.116.0/22204.235.116.1 to 204.235.119.254204.235.119.2551,022
223204.235.120.0/22204.235.120.1 to 204.235.123.254204.235.123.2551,022
224204.235.124.0/22204.235.124.1 to 204.235.127.254204.235.127.2551,022
225204.235.128.0/22204.235.128.1 to 204.235.131.254204.235.131.2551,022
226204.235.132.0/22204.235.132.1 to 204.235.135.254204.235.135.2551,022
227204.235.136.0/22204.235.136.1 to 204.235.139.254204.235.139.2551,022
228204.235.140.0/22204.235.140.1 to 204.235.143.254204.235.143.2551,022
229204.235.144.0/22204.235.144.1 to 204.235.147.254204.235.147.2551,022
230204.235.148.0/22204.235.148.1 to 204.235.151.254204.235.151.2551,022
231204.235.152.0/22204.235.152.1 to 204.235.155.254204.235.155.2551,022
232204.235.156.0/22204.235.156.1 to 204.235.159.254204.235.159.2551,022
233204.235.160.0/22204.235.160.1 to 204.235.163.254204.235.163.2551,022
234204.235.164.0/22204.235.164.1 to 204.235.167.254204.235.167.2551,022
235204.235.168.0/22204.235.168.1 to 204.235.171.254204.235.171.2551,022
236204.235.172.0/22204.235.172.1 to 204.235.175.254204.235.175.2551,022
237204.235.176.0/22204.235.176.1 to 204.235.179.254204.235.179.2551,022
238204.235.180.0/22204.235.180.1 to 204.235.183.254204.235.183.2551,022
239204.235.184.0/22204.235.184.1 to 204.235.187.254204.235.187.2551,022
240204.235.188.0/22204.235.188.1 to 204.235.191.254204.235.191.2551,022
241204.235.192.0/22204.235.192.1 to 204.235.195.254204.235.195.2551,022
242204.235.196.0/22204.235.196.1 to 204.235.199.254204.235.199.2551,022
243204.235.200.0/22204.235.200.1 to 204.235.203.254204.235.203.2551,022
244204.235.204.0/22204.235.204.1 to 204.235.207.254204.235.207.2551,022
245204.235.208.0/22204.235.208.1 to 204.235.211.254204.235.211.2551,022
246204.235.212.0/22204.235.212.1 to 204.235.215.254204.235.215.2551,022
247204.235.216.0/22204.235.216.1 to 204.235.219.254204.235.219.2551,022
248204.235.220.0/22204.235.220.1 to 204.235.223.254204.235.223.2551,022
249204.235.224.0/22204.235.224.1 to 204.235.227.254204.235.227.2551,022
250204.235.228.0/22204.235.228.1 to 204.235.231.254204.235.231.2551,022
251204.235.232.0/22204.235.232.1 to 204.235.235.254204.235.235.2551,022
252204.235.236.0/22204.235.236.1 to 204.235.239.254204.235.239.2551,022
253204.235.240.0/22204.235.240.1 to 204.235.243.254204.235.243.2551,022
254204.235.244.0/22204.235.244.1 to 204.235.247.254204.235.247.2551,022
255204.235.248.0/22204.235.248.1 to 204.235.251.254204.235.251.2551,022
256204.235.252.0/22204.235.252.1 to 204.235.255.254204.235.255.2551,022

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.