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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.

Network234.128.0.0/10
Usable hosts4,194,302
Subnet mask255.192.0.0
Addresses4,194,304
Network address
234.128.0.0
Broadcast address
234.191.255.255
First usable
234.128.0.1
Last usable
234.191.255.254
Usable hosts
4,194,302 (4,194,304 less the network and broadcast addresses)
Subnet mask
255.192.0.0
Wildcard mask
0.63.255.255 (Cisco ACLs, OSPF)
Prefix length
/10
Type
Multicast 224.0.0.0/4
One-to-many traffic, such as IPTV and routing protocols
Old class
D (multicast)
As numbers
Hex EA800000 · Integer 3934257152 to 3938451455
Reverse DNS zones
128.234.in-addr.arpa
129.234.in-addr.arpa
130.234.in-addr.arpa
131.234.in-addr.arpa
132.234.in-addr.arpa
133.234.in-addr.arpa
134.234.in-addr.arpa
135.234.in-addr.arpa
136.234.in-addr.arpa
137.234.in-addr.arpa
138.234.in-addr.arpa
139.234.in-addr.arpa
140.234.in-addr.arpa
141.234.in-addr.arpa
142.234.in-addr.arpa
143.234.in-addr.arpa
and 48 more
/10 is not on a 8-bit boundary, so it takes 64 /16 zones.
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address11101010.10000000.00000000.00000000234.128.0.0
Subnet mask11111111.11000000.00000000.00000000255.192.0.0
Network11101010.10000000.00000000.00000000234.128.0.0
Broadcast11101010.10111111.11111111.11111111234.191.255.255
Split into smaller subnets/22
/11 (2)/12 (4)/13 (8)/14 (16)/15 (32)/16 (64)/17 (128)/18 (256)/19 (512)/20 (1,024)/21 (2,048)/22 (4,096)

234.128.0.0/10 makes 4,096 subnets of /22; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
1234.128.0.0/22234.128.0.1 to 234.128.3.254234.128.3.2551,022
2234.128.4.0/22234.128.4.1 to 234.128.7.254234.128.7.2551,022
3234.128.8.0/22234.128.8.1 to 234.128.11.254234.128.11.2551,022
4234.128.12.0/22234.128.12.1 to 234.128.15.254234.128.15.2551,022
5234.128.16.0/22234.128.16.1 to 234.128.19.254234.128.19.2551,022
6234.128.20.0/22234.128.20.1 to 234.128.23.254234.128.23.2551,022
7234.128.24.0/22234.128.24.1 to 234.128.27.254234.128.27.2551,022
8234.128.28.0/22234.128.28.1 to 234.128.31.254234.128.31.2551,022
9234.128.32.0/22234.128.32.1 to 234.128.35.254234.128.35.2551,022
10234.128.36.0/22234.128.36.1 to 234.128.39.254234.128.39.2551,022
11234.128.40.0/22234.128.40.1 to 234.128.43.254234.128.43.2551,022
12234.128.44.0/22234.128.44.1 to 234.128.47.254234.128.47.2551,022
13234.128.48.0/22234.128.48.1 to 234.128.51.254234.128.51.2551,022
14234.128.52.0/22234.128.52.1 to 234.128.55.254234.128.55.2551,022
15234.128.56.0/22234.128.56.1 to 234.128.59.254234.128.59.2551,022
16234.128.60.0/22234.128.60.1 to 234.128.63.254234.128.63.2551,022
17234.128.64.0/22234.128.64.1 to 234.128.67.254234.128.67.2551,022
18234.128.68.0/22234.128.68.1 to 234.128.71.254234.128.71.2551,022
19234.128.72.0/22234.128.72.1 to 234.128.75.254234.128.75.2551,022
20234.128.76.0/22234.128.76.1 to 234.128.79.254234.128.79.2551,022
21234.128.80.0/22234.128.80.1 to 234.128.83.254234.128.83.2551,022
22234.128.84.0/22234.128.84.1 to 234.128.87.254234.128.87.2551,022
23234.128.88.0/22234.128.88.1 to 234.128.91.254234.128.91.2551,022
24234.128.92.0/22234.128.92.1 to 234.128.95.254234.128.95.2551,022
25234.128.96.0/22234.128.96.1 to 234.128.99.254234.128.99.2551,022
26234.128.100.0/22234.128.100.1 to 234.128.103.254234.128.103.2551,022
27234.128.104.0/22234.128.104.1 to 234.128.107.254234.128.107.2551,022
28234.128.108.0/22234.128.108.1 to 234.128.111.254234.128.111.2551,022
29234.128.112.0/22234.128.112.1 to 234.128.115.254234.128.115.2551,022
30234.128.116.0/22234.128.116.1 to 234.128.119.254234.128.119.2551,022
31234.128.120.0/22234.128.120.1 to 234.128.123.254234.128.123.2551,022
32234.128.124.0/22234.128.124.1 to 234.128.127.254234.128.127.2551,022
33234.128.128.0/22234.128.128.1 to 234.128.131.254234.128.131.2551,022
34234.128.132.0/22234.128.132.1 to 234.128.135.254234.128.135.2551,022
35234.128.136.0/22234.128.136.1 to 234.128.139.254234.128.139.2551,022
36234.128.140.0/22234.128.140.1 to 234.128.143.254234.128.143.2551,022
37234.128.144.0/22234.128.144.1 to 234.128.147.254234.128.147.2551,022
38234.128.148.0/22234.128.148.1 to 234.128.151.254234.128.151.2551,022
39234.128.152.0/22234.128.152.1 to 234.128.155.254234.128.155.2551,022
40234.128.156.0/22234.128.156.1 to 234.128.159.254234.128.159.2551,022
41234.128.160.0/22234.128.160.1 to 234.128.163.254234.128.163.2551,022
42234.128.164.0/22234.128.164.1 to 234.128.167.254234.128.167.2551,022
43234.128.168.0/22234.128.168.1 to 234.128.171.254234.128.171.2551,022
44234.128.172.0/22234.128.172.1 to 234.128.175.254234.128.175.2551,022
45234.128.176.0/22234.128.176.1 to 234.128.179.254234.128.179.2551,022
46234.128.180.0/22234.128.180.1 to 234.128.183.254234.128.183.2551,022
47234.128.184.0/22234.128.184.1 to 234.128.187.254234.128.187.2551,022
48234.128.188.0/22234.128.188.1 to 234.128.191.254234.128.191.2551,022
49234.128.192.0/22234.128.192.1 to 234.128.195.254234.128.195.2551,022
50234.128.196.0/22234.128.196.1 to 234.128.199.254234.128.199.2551,022
51234.128.200.0/22234.128.200.1 to 234.128.203.254234.128.203.2551,022
52234.128.204.0/22234.128.204.1 to 234.128.207.254234.128.207.2551,022
53234.128.208.0/22234.128.208.1 to 234.128.211.254234.128.211.2551,022
54234.128.212.0/22234.128.212.1 to 234.128.215.254234.128.215.2551,022
55234.128.216.0/22234.128.216.1 to 234.128.219.254234.128.219.2551,022
56234.128.220.0/22234.128.220.1 to 234.128.223.254234.128.223.2551,022
57234.128.224.0/22234.128.224.1 to 234.128.227.254234.128.227.2551,022
58234.128.228.0/22234.128.228.1 to 234.128.231.254234.128.231.2551,022
59234.128.232.0/22234.128.232.1 to 234.128.235.254234.128.235.2551,022
60234.128.236.0/22234.128.236.1 to 234.128.239.254234.128.239.2551,022
61234.128.240.0/22234.128.240.1 to 234.128.243.254234.128.243.2551,022
62234.128.244.0/22234.128.244.1 to 234.128.247.254234.128.247.2551,022
63234.128.248.0/22234.128.248.1 to 234.128.251.254234.128.251.2551,022
64234.128.252.0/22234.128.252.1 to 234.128.255.254234.128.255.2551,022
65234.129.0.0/22234.129.0.1 to 234.129.3.254234.129.3.2551,022
66234.129.4.0/22234.129.4.1 to 234.129.7.254234.129.7.2551,022
67234.129.8.0/22234.129.8.1 to 234.129.11.254234.129.11.2551,022
68234.129.12.0/22234.129.12.1 to 234.129.15.254234.129.15.2551,022
69234.129.16.0/22234.129.16.1 to 234.129.19.254234.129.19.2551,022
70234.129.20.0/22234.129.20.1 to 234.129.23.254234.129.23.2551,022
71234.129.24.0/22234.129.24.1 to 234.129.27.254234.129.27.2551,022
72234.129.28.0/22234.129.28.1 to 234.129.31.254234.129.31.2551,022
73234.129.32.0/22234.129.32.1 to 234.129.35.254234.129.35.2551,022
74234.129.36.0/22234.129.36.1 to 234.129.39.254234.129.39.2551,022
75234.129.40.0/22234.129.40.1 to 234.129.43.254234.129.43.2551,022
76234.129.44.0/22234.129.44.1 to 234.129.47.254234.129.47.2551,022
77234.129.48.0/22234.129.48.1 to 234.129.51.254234.129.51.2551,022
78234.129.52.0/22234.129.52.1 to 234.129.55.254234.129.55.2551,022
79234.129.56.0/22234.129.56.1 to 234.129.59.254234.129.59.2551,022
80234.129.60.0/22234.129.60.1 to 234.129.63.254234.129.63.2551,022
81234.129.64.0/22234.129.64.1 to 234.129.67.254234.129.67.2551,022
82234.129.68.0/22234.129.68.1 to 234.129.71.254234.129.71.2551,022
83234.129.72.0/22234.129.72.1 to 234.129.75.254234.129.75.2551,022
84234.129.76.0/22234.129.76.1 to 234.129.79.254234.129.79.2551,022
85234.129.80.0/22234.129.80.1 to 234.129.83.254234.129.83.2551,022
86234.129.84.0/22234.129.84.1 to 234.129.87.254234.129.87.2551,022
87234.129.88.0/22234.129.88.1 to 234.129.91.254234.129.91.2551,022
88234.129.92.0/22234.129.92.1 to 234.129.95.254234.129.95.2551,022
89234.129.96.0/22234.129.96.1 to 234.129.99.254234.129.99.2551,022
90234.129.100.0/22234.129.100.1 to 234.129.103.254234.129.103.2551,022
91234.129.104.0/22234.129.104.1 to 234.129.107.254234.129.107.2551,022
92234.129.108.0/22234.129.108.1 to 234.129.111.254234.129.111.2551,022
93234.129.112.0/22234.129.112.1 to 234.129.115.254234.129.115.2551,022
94234.129.116.0/22234.129.116.1 to 234.129.119.254234.129.119.2551,022
95234.129.120.0/22234.129.120.1 to 234.129.123.254234.129.123.2551,022
96234.129.124.0/22234.129.124.1 to 234.129.127.254234.129.127.2551,022
97234.129.128.0/22234.129.128.1 to 234.129.131.254234.129.131.2551,022
98234.129.132.0/22234.129.132.1 to 234.129.135.254234.129.135.2551,022
99234.129.136.0/22234.129.136.1 to 234.129.139.254234.129.139.2551,022
100234.129.140.0/22234.129.140.1 to 234.129.143.254234.129.143.2551,022
101234.129.144.0/22234.129.144.1 to 234.129.147.254234.129.147.2551,022
102234.129.148.0/22234.129.148.1 to 234.129.151.254234.129.151.2551,022
103234.129.152.0/22234.129.152.1 to 234.129.155.254234.129.155.2551,022
104234.129.156.0/22234.129.156.1 to 234.129.159.254234.129.159.2551,022
105234.129.160.0/22234.129.160.1 to 234.129.163.254234.129.163.2551,022
106234.129.164.0/22234.129.164.1 to 234.129.167.254234.129.167.2551,022
107234.129.168.0/22234.129.168.1 to 234.129.171.254234.129.171.2551,022
108234.129.172.0/22234.129.172.1 to 234.129.175.254234.129.175.2551,022
109234.129.176.0/22234.129.176.1 to 234.129.179.254234.129.179.2551,022
110234.129.180.0/22234.129.180.1 to 234.129.183.254234.129.183.2551,022
111234.129.184.0/22234.129.184.1 to 234.129.187.254234.129.187.2551,022
112234.129.188.0/22234.129.188.1 to 234.129.191.254234.129.191.2551,022
113234.129.192.0/22234.129.192.1 to 234.129.195.254234.129.195.2551,022
114234.129.196.0/22234.129.196.1 to 234.129.199.254234.129.199.2551,022
115234.129.200.0/22234.129.200.1 to 234.129.203.254234.129.203.2551,022
116234.129.204.0/22234.129.204.1 to 234.129.207.254234.129.207.2551,022
117234.129.208.0/22234.129.208.1 to 234.129.211.254234.129.211.2551,022
118234.129.212.0/22234.129.212.1 to 234.129.215.254234.129.215.2551,022
119234.129.216.0/22234.129.216.1 to 234.129.219.254234.129.219.2551,022
120234.129.220.0/22234.129.220.1 to 234.129.223.254234.129.223.2551,022
121234.129.224.0/22234.129.224.1 to 234.129.227.254234.129.227.2551,022
122234.129.228.0/22234.129.228.1 to 234.129.231.254234.129.231.2551,022
123234.129.232.0/22234.129.232.1 to 234.129.235.254234.129.235.2551,022
124234.129.236.0/22234.129.236.1 to 234.129.239.254234.129.239.2551,022
125234.129.240.0/22234.129.240.1 to 234.129.243.254234.129.243.2551,022
126234.129.244.0/22234.129.244.1 to 234.129.247.254234.129.247.2551,022
127234.129.248.0/22234.129.248.1 to 234.129.251.254234.129.251.2551,022
128234.129.252.0/22234.129.252.1 to 234.129.255.254234.129.255.2551,022
129234.130.0.0/22234.130.0.1 to 234.130.3.254234.130.3.2551,022
130234.130.4.0/22234.130.4.1 to 234.130.7.254234.130.7.2551,022
131234.130.8.0/22234.130.8.1 to 234.130.11.254234.130.11.2551,022
132234.130.12.0/22234.130.12.1 to 234.130.15.254234.130.15.2551,022
133234.130.16.0/22234.130.16.1 to 234.130.19.254234.130.19.2551,022
134234.130.20.0/22234.130.20.1 to 234.130.23.254234.130.23.2551,022
135234.130.24.0/22234.130.24.1 to 234.130.27.254234.130.27.2551,022
136234.130.28.0/22234.130.28.1 to 234.130.31.254234.130.31.2551,022
137234.130.32.0/22234.130.32.1 to 234.130.35.254234.130.35.2551,022
138234.130.36.0/22234.130.36.1 to 234.130.39.254234.130.39.2551,022
139234.130.40.0/22234.130.40.1 to 234.130.43.254234.130.43.2551,022
140234.130.44.0/22234.130.44.1 to 234.130.47.254234.130.47.2551,022
141234.130.48.0/22234.130.48.1 to 234.130.51.254234.130.51.2551,022
142234.130.52.0/22234.130.52.1 to 234.130.55.254234.130.55.2551,022
143234.130.56.0/22234.130.56.1 to 234.130.59.254234.130.59.2551,022
144234.130.60.0/22234.130.60.1 to 234.130.63.254234.130.63.2551,022
145234.130.64.0/22234.130.64.1 to 234.130.67.254234.130.67.2551,022
146234.130.68.0/22234.130.68.1 to 234.130.71.254234.130.71.2551,022
147234.130.72.0/22234.130.72.1 to 234.130.75.254234.130.75.2551,022
148234.130.76.0/22234.130.76.1 to 234.130.79.254234.130.79.2551,022
149234.130.80.0/22234.130.80.1 to 234.130.83.254234.130.83.2551,022
150234.130.84.0/22234.130.84.1 to 234.130.87.254234.130.87.2551,022
151234.130.88.0/22234.130.88.1 to 234.130.91.254234.130.91.2551,022
152234.130.92.0/22234.130.92.1 to 234.130.95.254234.130.95.2551,022
153234.130.96.0/22234.130.96.1 to 234.130.99.254234.130.99.2551,022
154234.130.100.0/22234.130.100.1 to 234.130.103.254234.130.103.2551,022
155234.130.104.0/22234.130.104.1 to 234.130.107.254234.130.107.2551,022
156234.130.108.0/22234.130.108.1 to 234.130.111.254234.130.111.2551,022
157234.130.112.0/22234.130.112.1 to 234.130.115.254234.130.115.2551,022
158234.130.116.0/22234.130.116.1 to 234.130.119.254234.130.119.2551,022
159234.130.120.0/22234.130.120.1 to 234.130.123.254234.130.123.2551,022
160234.130.124.0/22234.130.124.1 to 234.130.127.254234.130.127.2551,022
161234.130.128.0/22234.130.128.1 to 234.130.131.254234.130.131.2551,022
162234.130.132.0/22234.130.132.1 to 234.130.135.254234.130.135.2551,022
163234.130.136.0/22234.130.136.1 to 234.130.139.254234.130.139.2551,022
164234.130.140.0/22234.130.140.1 to 234.130.143.254234.130.143.2551,022
165234.130.144.0/22234.130.144.1 to 234.130.147.254234.130.147.2551,022
166234.130.148.0/22234.130.148.1 to 234.130.151.254234.130.151.2551,022
167234.130.152.0/22234.130.152.1 to 234.130.155.254234.130.155.2551,022
168234.130.156.0/22234.130.156.1 to 234.130.159.254234.130.159.2551,022
169234.130.160.0/22234.130.160.1 to 234.130.163.254234.130.163.2551,022
170234.130.164.0/22234.130.164.1 to 234.130.167.254234.130.167.2551,022
171234.130.168.0/22234.130.168.1 to 234.130.171.254234.130.171.2551,022
172234.130.172.0/22234.130.172.1 to 234.130.175.254234.130.175.2551,022
173234.130.176.0/22234.130.176.1 to 234.130.179.254234.130.179.2551,022
174234.130.180.0/22234.130.180.1 to 234.130.183.254234.130.183.2551,022
175234.130.184.0/22234.130.184.1 to 234.130.187.254234.130.187.2551,022
176234.130.188.0/22234.130.188.1 to 234.130.191.254234.130.191.2551,022
177234.130.192.0/22234.130.192.1 to 234.130.195.254234.130.195.2551,022
178234.130.196.0/22234.130.196.1 to 234.130.199.254234.130.199.2551,022
179234.130.200.0/22234.130.200.1 to 234.130.203.254234.130.203.2551,022
180234.130.204.0/22234.130.204.1 to 234.130.207.254234.130.207.2551,022
181234.130.208.0/22234.130.208.1 to 234.130.211.254234.130.211.2551,022
182234.130.212.0/22234.130.212.1 to 234.130.215.254234.130.215.2551,022
183234.130.216.0/22234.130.216.1 to 234.130.219.254234.130.219.2551,022
184234.130.220.0/22234.130.220.1 to 234.130.223.254234.130.223.2551,022
185234.130.224.0/22234.130.224.1 to 234.130.227.254234.130.227.2551,022
186234.130.228.0/22234.130.228.1 to 234.130.231.254234.130.231.2551,022
187234.130.232.0/22234.130.232.1 to 234.130.235.254234.130.235.2551,022
188234.130.236.0/22234.130.236.1 to 234.130.239.254234.130.239.2551,022
189234.130.240.0/22234.130.240.1 to 234.130.243.254234.130.243.2551,022
190234.130.244.0/22234.130.244.1 to 234.130.247.254234.130.247.2551,022
191234.130.248.0/22234.130.248.1 to 234.130.251.254234.130.251.2551,022
192234.130.252.0/22234.130.252.1 to 234.130.255.254234.130.255.2551,022
193234.131.0.0/22234.131.0.1 to 234.131.3.254234.131.3.2551,022
194234.131.4.0/22234.131.4.1 to 234.131.7.254234.131.7.2551,022
195234.131.8.0/22234.131.8.1 to 234.131.11.254234.131.11.2551,022
196234.131.12.0/22234.131.12.1 to 234.131.15.254234.131.15.2551,022
197234.131.16.0/22234.131.16.1 to 234.131.19.254234.131.19.2551,022
198234.131.20.0/22234.131.20.1 to 234.131.23.254234.131.23.2551,022
199234.131.24.0/22234.131.24.1 to 234.131.27.254234.131.27.2551,022
200234.131.28.0/22234.131.28.1 to 234.131.31.254234.131.31.2551,022
201234.131.32.0/22234.131.32.1 to 234.131.35.254234.131.35.2551,022
202234.131.36.0/22234.131.36.1 to 234.131.39.254234.131.39.2551,022
203234.131.40.0/22234.131.40.1 to 234.131.43.254234.131.43.2551,022
204234.131.44.0/22234.131.44.1 to 234.131.47.254234.131.47.2551,022
205234.131.48.0/22234.131.48.1 to 234.131.51.254234.131.51.2551,022
206234.131.52.0/22234.131.52.1 to 234.131.55.254234.131.55.2551,022
207234.131.56.0/22234.131.56.1 to 234.131.59.254234.131.59.2551,022
208234.131.60.0/22234.131.60.1 to 234.131.63.254234.131.63.2551,022
209234.131.64.0/22234.131.64.1 to 234.131.67.254234.131.67.2551,022
210234.131.68.0/22234.131.68.1 to 234.131.71.254234.131.71.2551,022
211234.131.72.0/22234.131.72.1 to 234.131.75.254234.131.75.2551,022
212234.131.76.0/22234.131.76.1 to 234.131.79.254234.131.79.2551,022
213234.131.80.0/22234.131.80.1 to 234.131.83.254234.131.83.2551,022
214234.131.84.0/22234.131.84.1 to 234.131.87.254234.131.87.2551,022
215234.131.88.0/22234.131.88.1 to 234.131.91.254234.131.91.2551,022
216234.131.92.0/22234.131.92.1 to 234.131.95.254234.131.95.2551,022
217234.131.96.0/22234.131.96.1 to 234.131.99.254234.131.99.2551,022
218234.131.100.0/22234.131.100.1 to 234.131.103.254234.131.103.2551,022
219234.131.104.0/22234.131.104.1 to 234.131.107.254234.131.107.2551,022
220234.131.108.0/22234.131.108.1 to 234.131.111.254234.131.111.2551,022
221234.131.112.0/22234.131.112.1 to 234.131.115.254234.131.115.2551,022
222234.131.116.0/22234.131.116.1 to 234.131.119.254234.131.119.2551,022
223234.131.120.0/22234.131.120.1 to 234.131.123.254234.131.123.2551,022
224234.131.124.0/22234.131.124.1 to 234.131.127.254234.131.127.2551,022
225234.131.128.0/22234.131.128.1 to 234.131.131.254234.131.131.2551,022
226234.131.132.0/22234.131.132.1 to 234.131.135.254234.131.135.2551,022
227234.131.136.0/22234.131.136.1 to 234.131.139.254234.131.139.2551,022
228234.131.140.0/22234.131.140.1 to 234.131.143.254234.131.143.2551,022
229234.131.144.0/22234.131.144.1 to 234.131.147.254234.131.147.2551,022
230234.131.148.0/22234.131.148.1 to 234.131.151.254234.131.151.2551,022
231234.131.152.0/22234.131.152.1 to 234.131.155.254234.131.155.2551,022
232234.131.156.0/22234.131.156.1 to 234.131.159.254234.131.159.2551,022
233234.131.160.0/22234.131.160.1 to 234.131.163.254234.131.163.2551,022
234234.131.164.0/22234.131.164.1 to 234.131.167.254234.131.167.2551,022
235234.131.168.0/22234.131.168.1 to 234.131.171.254234.131.171.2551,022
236234.131.172.0/22234.131.172.1 to 234.131.175.254234.131.175.2551,022
237234.131.176.0/22234.131.176.1 to 234.131.179.254234.131.179.2551,022
238234.131.180.0/22234.131.180.1 to 234.131.183.254234.131.183.2551,022
239234.131.184.0/22234.131.184.1 to 234.131.187.254234.131.187.2551,022
240234.131.188.0/22234.131.188.1 to 234.131.191.254234.131.191.2551,022
241234.131.192.0/22234.131.192.1 to 234.131.195.254234.131.195.2551,022
242234.131.196.0/22234.131.196.1 to 234.131.199.254234.131.199.2551,022
243234.131.200.0/22234.131.200.1 to 234.131.203.254234.131.203.2551,022
244234.131.204.0/22234.131.204.1 to 234.131.207.254234.131.207.2551,022
245234.131.208.0/22234.131.208.1 to 234.131.211.254234.131.211.2551,022
246234.131.212.0/22234.131.212.1 to 234.131.215.254234.131.215.2551,022
247234.131.216.0/22234.131.216.1 to 234.131.219.254234.131.219.2551,022
248234.131.220.0/22234.131.220.1 to 234.131.223.254234.131.223.2551,022
249234.131.224.0/22234.131.224.1 to 234.131.227.254234.131.227.2551,022
250234.131.228.0/22234.131.228.1 to 234.131.231.254234.131.231.2551,022
251234.131.232.0/22234.131.232.1 to 234.131.235.254234.131.235.2551,022
252234.131.236.0/22234.131.236.1 to 234.131.239.254234.131.239.2551,022
253234.131.240.0/22234.131.240.1 to 234.131.243.254234.131.243.2551,022
254234.131.244.0/22234.131.244.1 to 234.131.247.254234.131.247.2551,022
255234.131.248.0/22234.131.248.1 to 234.131.251.254234.131.251.2551,022
256234.131.252.0/22234.131.252.1 to 234.131.255.254234.131.255.2551,022

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.