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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.

Network238.160.0.0/11
Usable hosts2,097,150
Subnet mask255.224.0.0
Addresses2,097,152
Network address
238.160.0.0
Broadcast address
238.191.255.255
First usable
238.160.0.1
Last usable
238.191.255.254
Usable hosts
2,097,150 (2,097,152 less the network and broadcast addresses)
Subnet mask
255.224.0.0
Wildcard mask
0.31.255.255 (Cisco ACLs, OSPF)
Prefix length
/11
Type
Multicast 224.0.0.0/4
One-to-many traffic, such as IPTV and routing protocols
Old class
D (multicast)
As numbers
Hex EEA00000 · Integer 4003463168 to 4005560319
Reverse DNS zones
160.238.in-addr.arpa
161.238.in-addr.arpa
162.238.in-addr.arpa
163.238.in-addr.arpa
164.238.in-addr.arpa
165.238.in-addr.arpa
166.238.in-addr.arpa
167.238.in-addr.arpa
168.238.in-addr.arpa
169.238.in-addr.arpa
170.238.in-addr.arpa
171.238.in-addr.arpa
172.238.in-addr.arpa
173.238.in-addr.arpa
174.238.in-addr.arpa
175.238.in-addr.arpa
and 16 more
/11 is not on a 8-bit boundary, so it takes 32 /16 zones.
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address11101110.10100000.00000000.00000000238.160.0.0
Subnet mask11111111.11100000.00000000.00000000255.224.0.0
Network11101110.10100000.00000000.00000000238.160.0.0
Broadcast11101110.10111111.11111111.11111111238.191.255.255
Split into smaller subnets/23
/12 (2)/13 (4)/14 (8)/15 (16)/16 (32)/17 (64)/18 (128)/19 (256)/20 (512)/21 (1,024)/22 (2,048)/23 (4,096)

238.160.0.0/11 makes 4,096 subnets of /23; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
1238.160.0.0/23238.160.0.1 to 238.160.1.254238.160.1.255510
2238.160.2.0/23238.160.2.1 to 238.160.3.254238.160.3.255510
3238.160.4.0/23238.160.4.1 to 238.160.5.254238.160.5.255510
4238.160.6.0/23238.160.6.1 to 238.160.7.254238.160.7.255510
5238.160.8.0/23238.160.8.1 to 238.160.9.254238.160.9.255510
6238.160.10.0/23238.160.10.1 to 238.160.11.254238.160.11.255510
7238.160.12.0/23238.160.12.1 to 238.160.13.254238.160.13.255510
8238.160.14.0/23238.160.14.1 to 238.160.15.254238.160.15.255510
9238.160.16.0/23238.160.16.1 to 238.160.17.254238.160.17.255510
10238.160.18.0/23238.160.18.1 to 238.160.19.254238.160.19.255510
11238.160.20.0/23238.160.20.1 to 238.160.21.254238.160.21.255510
12238.160.22.0/23238.160.22.1 to 238.160.23.254238.160.23.255510
13238.160.24.0/23238.160.24.1 to 238.160.25.254238.160.25.255510
14238.160.26.0/23238.160.26.1 to 238.160.27.254238.160.27.255510
15238.160.28.0/23238.160.28.1 to 238.160.29.254238.160.29.255510
16238.160.30.0/23238.160.30.1 to 238.160.31.254238.160.31.255510
17238.160.32.0/23238.160.32.1 to 238.160.33.254238.160.33.255510
18238.160.34.0/23238.160.34.1 to 238.160.35.254238.160.35.255510
19238.160.36.0/23238.160.36.1 to 238.160.37.254238.160.37.255510
20238.160.38.0/23238.160.38.1 to 238.160.39.254238.160.39.255510
21238.160.40.0/23238.160.40.1 to 238.160.41.254238.160.41.255510
22238.160.42.0/23238.160.42.1 to 238.160.43.254238.160.43.255510
23238.160.44.0/23238.160.44.1 to 238.160.45.254238.160.45.255510
24238.160.46.0/23238.160.46.1 to 238.160.47.254238.160.47.255510
25238.160.48.0/23238.160.48.1 to 238.160.49.254238.160.49.255510
26238.160.50.0/23238.160.50.1 to 238.160.51.254238.160.51.255510
27238.160.52.0/23238.160.52.1 to 238.160.53.254238.160.53.255510
28238.160.54.0/23238.160.54.1 to 238.160.55.254238.160.55.255510
29238.160.56.0/23238.160.56.1 to 238.160.57.254238.160.57.255510
30238.160.58.0/23238.160.58.1 to 238.160.59.254238.160.59.255510
31238.160.60.0/23238.160.60.1 to 238.160.61.254238.160.61.255510
32238.160.62.0/23238.160.62.1 to 238.160.63.254238.160.63.255510
33238.160.64.0/23238.160.64.1 to 238.160.65.254238.160.65.255510
34238.160.66.0/23238.160.66.1 to 238.160.67.254238.160.67.255510
35238.160.68.0/23238.160.68.1 to 238.160.69.254238.160.69.255510
36238.160.70.0/23238.160.70.1 to 238.160.71.254238.160.71.255510
37238.160.72.0/23238.160.72.1 to 238.160.73.254238.160.73.255510
38238.160.74.0/23238.160.74.1 to 238.160.75.254238.160.75.255510
39238.160.76.0/23238.160.76.1 to 238.160.77.254238.160.77.255510
40238.160.78.0/23238.160.78.1 to 238.160.79.254238.160.79.255510
41238.160.80.0/23238.160.80.1 to 238.160.81.254238.160.81.255510
42238.160.82.0/23238.160.82.1 to 238.160.83.254238.160.83.255510
43238.160.84.0/23238.160.84.1 to 238.160.85.254238.160.85.255510
44238.160.86.0/23238.160.86.1 to 238.160.87.254238.160.87.255510
45238.160.88.0/23238.160.88.1 to 238.160.89.254238.160.89.255510
46238.160.90.0/23238.160.90.1 to 238.160.91.254238.160.91.255510
47238.160.92.0/23238.160.92.1 to 238.160.93.254238.160.93.255510
48238.160.94.0/23238.160.94.1 to 238.160.95.254238.160.95.255510
49238.160.96.0/23238.160.96.1 to 238.160.97.254238.160.97.255510
50238.160.98.0/23238.160.98.1 to 238.160.99.254238.160.99.255510
51238.160.100.0/23238.160.100.1 to 238.160.101.254238.160.101.255510
52238.160.102.0/23238.160.102.1 to 238.160.103.254238.160.103.255510
53238.160.104.0/23238.160.104.1 to 238.160.105.254238.160.105.255510
54238.160.106.0/23238.160.106.1 to 238.160.107.254238.160.107.255510
55238.160.108.0/23238.160.108.1 to 238.160.109.254238.160.109.255510
56238.160.110.0/23238.160.110.1 to 238.160.111.254238.160.111.255510
57238.160.112.0/23238.160.112.1 to 238.160.113.254238.160.113.255510
58238.160.114.0/23238.160.114.1 to 238.160.115.254238.160.115.255510
59238.160.116.0/23238.160.116.1 to 238.160.117.254238.160.117.255510
60238.160.118.0/23238.160.118.1 to 238.160.119.254238.160.119.255510
61238.160.120.0/23238.160.120.1 to 238.160.121.254238.160.121.255510
62238.160.122.0/23238.160.122.1 to 238.160.123.254238.160.123.255510
63238.160.124.0/23238.160.124.1 to 238.160.125.254238.160.125.255510
64238.160.126.0/23238.160.126.1 to 238.160.127.254238.160.127.255510
65238.160.128.0/23238.160.128.1 to 238.160.129.254238.160.129.255510
66238.160.130.0/23238.160.130.1 to 238.160.131.254238.160.131.255510
67238.160.132.0/23238.160.132.1 to 238.160.133.254238.160.133.255510
68238.160.134.0/23238.160.134.1 to 238.160.135.254238.160.135.255510
69238.160.136.0/23238.160.136.1 to 238.160.137.254238.160.137.255510
70238.160.138.0/23238.160.138.1 to 238.160.139.254238.160.139.255510
71238.160.140.0/23238.160.140.1 to 238.160.141.254238.160.141.255510
72238.160.142.0/23238.160.142.1 to 238.160.143.254238.160.143.255510
73238.160.144.0/23238.160.144.1 to 238.160.145.254238.160.145.255510
74238.160.146.0/23238.160.146.1 to 238.160.147.254238.160.147.255510
75238.160.148.0/23238.160.148.1 to 238.160.149.254238.160.149.255510
76238.160.150.0/23238.160.150.1 to 238.160.151.254238.160.151.255510
77238.160.152.0/23238.160.152.1 to 238.160.153.254238.160.153.255510
78238.160.154.0/23238.160.154.1 to 238.160.155.254238.160.155.255510
79238.160.156.0/23238.160.156.1 to 238.160.157.254238.160.157.255510
80238.160.158.0/23238.160.158.1 to 238.160.159.254238.160.159.255510
81238.160.160.0/23238.160.160.1 to 238.160.161.254238.160.161.255510
82238.160.162.0/23238.160.162.1 to 238.160.163.254238.160.163.255510
83238.160.164.0/23238.160.164.1 to 238.160.165.254238.160.165.255510
84238.160.166.0/23238.160.166.1 to 238.160.167.254238.160.167.255510
85238.160.168.0/23238.160.168.1 to 238.160.169.254238.160.169.255510
86238.160.170.0/23238.160.170.1 to 238.160.171.254238.160.171.255510
87238.160.172.0/23238.160.172.1 to 238.160.173.254238.160.173.255510
88238.160.174.0/23238.160.174.1 to 238.160.175.254238.160.175.255510
89238.160.176.0/23238.160.176.1 to 238.160.177.254238.160.177.255510
90238.160.178.0/23238.160.178.1 to 238.160.179.254238.160.179.255510
91238.160.180.0/23238.160.180.1 to 238.160.181.254238.160.181.255510
92238.160.182.0/23238.160.182.1 to 238.160.183.254238.160.183.255510
93238.160.184.0/23238.160.184.1 to 238.160.185.254238.160.185.255510
94238.160.186.0/23238.160.186.1 to 238.160.187.254238.160.187.255510
95238.160.188.0/23238.160.188.1 to 238.160.189.254238.160.189.255510
96238.160.190.0/23238.160.190.1 to 238.160.191.254238.160.191.255510
97238.160.192.0/23238.160.192.1 to 238.160.193.254238.160.193.255510
98238.160.194.0/23238.160.194.1 to 238.160.195.254238.160.195.255510
99238.160.196.0/23238.160.196.1 to 238.160.197.254238.160.197.255510
100238.160.198.0/23238.160.198.1 to 238.160.199.254238.160.199.255510
101238.160.200.0/23238.160.200.1 to 238.160.201.254238.160.201.255510
102238.160.202.0/23238.160.202.1 to 238.160.203.254238.160.203.255510
103238.160.204.0/23238.160.204.1 to 238.160.205.254238.160.205.255510
104238.160.206.0/23238.160.206.1 to 238.160.207.254238.160.207.255510
105238.160.208.0/23238.160.208.1 to 238.160.209.254238.160.209.255510
106238.160.210.0/23238.160.210.1 to 238.160.211.254238.160.211.255510
107238.160.212.0/23238.160.212.1 to 238.160.213.254238.160.213.255510
108238.160.214.0/23238.160.214.1 to 238.160.215.254238.160.215.255510
109238.160.216.0/23238.160.216.1 to 238.160.217.254238.160.217.255510
110238.160.218.0/23238.160.218.1 to 238.160.219.254238.160.219.255510
111238.160.220.0/23238.160.220.1 to 238.160.221.254238.160.221.255510
112238.160.222.0/23238.160.222.1 to 238.160.223.254238.160.223.255510
113238.160.224.0/23238.160.224.1 to 238.160.225.254238.160.225.255510
114238.160.226.0/23238.160.226.1 to 238.160.227.254238.160.227.255510
115238.160.228.0/23238.160.228.1 to 238.160.229.254238.160.229.255510
116238.160.230.0/23238.160.230.1 to 238.160.231.254238.160.231.255510
117238.160.232.0/23238.160.232.1 to 238.160.233.254238.160.233.255510
118238.160.234.0/23238.160.234.1 to 238.160.235.254238.160.235.255510
119238.160.236.0/23238.160.236.1 to 238.160.237.254238.160.237.255510
120238.160.238.0/23238.160.238.1 to 238.160.239.254238.160.239.255510
121238.160.240.0/23238.160.240.1 to 238.160.241.254238.160.241.255510
122238.160.242.0/23238.160.242.1 to 238.160.243.254238.160.243.255510
123238.160.244.0/23238.160.244.1 to 238.160.245.254238.160.245.255510
124238.160.246.0/23238.160.246.1 to 238.160.247.254238.160.247.255510
125238.160.248.0/23238.160.248.1 to 238.160.249.254238.160.249.255510
126238.160.250.0/23238.160.250.1 to 238.160.251.254238.160.251.255510
127238.160.252.0/23238.160.252.1 to 238.160.253.254238.160.253.255510
128238.160.254.0/23238.160.254.1 to 238.160.255.254238.160.255.255510
129238.161.0.0/23238.161.0.1 to 238.161.1.254238.161.1.255510
130238.161.2.0/23238.161.2.1 to 238.161.3.254238.161.3.255510
131238.161.4.0/23238.161.4.1 to 238.161.5.254238.161.5.255510
132238.161.6.0/23238.161.6.1 to 238.161.7.254238.161.7.255510
133238.161.8.0/23238.161.8.1 to 238.161.9.254238.161.9.255510
134238.161.10.0/23238.161.10.1 to 238.161.11.254238.161.11.255510
135238.161.12.0/23238.161.12.1 to 238.161.13.254238.161.13.255510
136238.161.14.0/23238.161.14.1 to 238.161.15.254238.161.15.255510
137238.161.16.0/23238.161.16.1 to 238.161.17.254238.161.17.255510
138238.161.18.0/23238.161.18.1 to 238.161.19.254238.161.19.255510
139238.161.20.0/23238.161.20.1 to 238.161.21.254238.161.21.255510
140238.161.22.0/23238.161.22.1 to 238.161.23.254238.161.23.255510
141238.161.24.0/23238.161.24.1 to 238.161.25.254238.161.25.255510
142238.161.26.0/23238.161.26.1 to 238.161.27.254238.161.27.255510
143238.161.28.0/23238.161.28.1 to 238.161.29.254238.161.29.255510
144238.161.30.0/23238.161.30.1 to 238.161.31.254238.161.31.255510
145238.161.32.0/23238.161.32.1 to 238.161.33.254238.161.33.255510
146238.161.34.0/23238.161.34.1 to 238.161.35.254238.161.35.255510
147238.161.36.0/23238.161.36.1 to 238.161.37.254238.161.37.255510
148238.161.38.0/23238.161.38.1 to 238.161.39.254238.161.39.255510
149238.161.40.0/23238.161.40.1 to 238.161.41.254238.161.41.255510
150238.161.42.0/23238.161.42.1 to 238.161.43.254238.161.43.255510
151238.161.44.0/23238.161.44.1 to 238.161.45.254238.161.45.255510
152238.161.46.0/23238.161.46.1 to 238.161.47.254238.161.47.255510
153238.161.48.0/23238.161.48.1 to 238.161.49.254238.161.49.255510
154238.161.50.0/23238.161.50.1 to 238.161.51.254238.161.51.255510
155238.161.52.0/23238.161.52.1 to 238.161.53.254238.161.53.255510
156238.161.54.0/23238.161.54.1 to 238.161.55.254238.161.55.255510
157238.161.56.0/23238.161.56.1 to 238.161.57.254238.161.57.255510
158238.161.58.0/23238.161.58.1 to 238.161.59.254238.161.59.255510
159238.161.60.0/23238.161.60.1 to 238.161.61.254238.161.61.255510
160238.161.62.0/23238.161.62.1 to 238.161.63.254238.161.63.255510
161238.161.64.0/23238.161.64.1 to 238.161.65.254238.161.65.255510
162238.161.66.0/23238.161.66.1 to 238.161.67.254238.161.67.255510
163238.161.68.0/23238.161.68.1 to 238.161.69.254238.161.69.255510
164238.161.70.0/23238.161.70.1 to 238.161.71.254238.161.71.255510
165238.161.72.0/23238.161.72.1 to 238.161.73.254238.161.73.255510
166238.161.74.0/23238.161.74.1 to 238.161.75.254238.161.75.255510
167238.161.76.0/23238.161.76.1 to 238.161.77.254238.161.77.255510
168238.161.78.0/23238.161.78.1 to 238.161.79.254238.161.79.255510
169238.161.80.0/23238.161.80.1 to 238.161.81.254238.161.81.255510
170238.161.82.0/23238.161.82.1 to 238.161.83.254238.161.83.255510
171238.161.84.0/23238.161.84.1 to 238.161.85.254238.161.85.255510
172238.161.86.0/23238.161.86.1 to 238.161.87.254238.161.87.255510
173238.161.88.0/23238.161.88.1 to 238.161.89.254238.161.89.255510
174238.161.90.0/23238.161.90.1 to 238.161.91.254238.161.91.255510
175238.161.92.0/23238.161.92.1 to 238.161.93.254238.161.93.255510
176238.161.94.0/23238.161.94.1 to 238.161.95.254238.161.95.255510
177238.161.96.0/23238.161.96.1 to 238.161.97.254238.161.97.255510
178238.161.98.0/23238.161.98.1 to 238.161.99.254238.161.99.255510
179238.161.100.0/23238.161.100.1 to 238.161.101.254238.161.101.255510
180238.161.102.0/23238.161.102.1 to 238.161.103.254238.161.103.255510
181238.161.104.0/23238.161.104.1 to 238.161.105.254238.161.105.255510
182238.161.106.0/23238.161.106.1 to 238.161.107.254238.161.107.255510
183238.161.108.0/23238.161.108.1 to 238.161.109.254238.161.109.255510
184238.161.110.0/23238.161.110.1 to 238.161.111.254238.161.111.255510
185238.161.112.0/23238.161.112.1 to 238.161.113.254238.161.113.255510
186238.161.114.0/23238.161.114.1 to 238.161.115.254238.161.115.255510
187238.161.116.0/23238.161.116.1 to 238.161.117.254238.161.117.255510
188238.161.118.0/23238.161.118.1 to 238.161.119.254238.161.119.255510
189238.161.120.0/23238.161.120.1 to 238.161.121.254238.161.121.255510
190238.161.122.0/23238.161.122.1 to 238.161.123.254238.161.123.255510
191238.161.124.0/23238.161.124.1 to 238.161.125.254238.161.125.255510
192238.161.126.0/23238.161.126.1 to 238.161.127.254238.161.127.255510
193238.161.128.0/23238.161.128.1 to 238.161.129.254238.161.129.255510
194238.161.130.0/23238.161.130.1 to 238.161.131.254238.161.131.255510
195238.161.132.0/23238.161.132.1 to 238.161.133.254238.161.133.255510
196238.161.134.0/23238.161.134.1 to 238.161.135.254238.161.135.255510
197238.161.136.0/23238.161.136.1 to 238.161.137.254238.161.137.255510
198238.161.138.0/23238.161.138.1 to 238.161.139.254238.161.139.255510
199238.161.140.0/23238.161.140.1 to 238.161.141.254238.161.141.255510
200238.161.142.0/23238.161.142.1 to 238.161.143.254238.161.143.255510
201238.161.144.0/23238.161.144.1 to 238.161.145.254238.161.145.255510
202238.161.146.0/23238.161.146.1 to 238.161.147.254238.161.147.255510
203238.161.148.0/23238.161.148.1 to 238.161.149.254238.161.149.255510
204238.161.150.0/23238.161.150.1 to 238.161.151.254238.161.151.255510
205238.161.152.0/23238.161.152.1 to 238.161.153.254238.161.153.255510
206238.161.154.0/23238.161.154.1 to 238.161.155.254238.161.155.255510
207238.161.156.0/23238.161.156.1 to 238.161.157.254238.161.157.255510
208238.161.158.0/23238.161.158.1 to 238.161.159.254238.161.159.255510
209238.161.160.0/23238.161.160.1 to 238.161.161.254238.161.161.255510
210238.161.162.0/23238.161.162.1 to 238.161.163.254238.161.163.255510
211238.161.164.0/23238.161.164.1 to 238.161.165.254238.161.165.255510
212238.161.166.0/23238.161.166.1 to 238.161.167.254238.161.167.255510
213238.161.168.0/23238.161.168.1 to 238.161.169.254238.161.169.255510
214238.161.170.0/23238.161.170.1 to 238.161.171.254238.161.171.255510
215238.161.172.0/23238.161.172.1 to 238.161.173.254238.161.173.255510
216238.161.174.0/23238.161.174.1 to 238.161.175.254238.161.175.255510
217238.161.176.0/23238.161.176.1 to 238.161.177.254238.161.177.255510
218238.161.178.0/23238.161.178.1 to 238.161.179.254238.161.179.255510
219238.161.180.0/23238.161.180.1 to 238.161.181.254238.161.181.255510
220238.161.182.0/23238.161.182.1 to 238.161.183.254238.161.183.255510
221238.161.184.0/23238.161.184.1 to 238.161.185.254238.161.185.255510
222238.161.186.0/23238.161.186.1 to 238.161.187.254238.161.187.255510
223238.161.188.0/23238.161.188.1 to 238.161.189.254238.161.189.255510
224238.161.190.0/23238.161.190.1 to 238.161.191.254238.161.191.255510
225238.161.192.0/23238.161.192.1 to 238.161.193.254238.161.193.255510
226238.161.194.0/23238.161.194.1 to 238.161.195.254238.161.195.255510
227238.161.196.0/23238.161.196.1 to 238.161.197.254238.161.197.255510
228238.161.198.0/23238.161.198.1 to 238.161.199.254238.161.199.255510
229238.161.200.0/23238.161.200.1 to 238.161.201.254238.161.201.255510
230238.161.202.0/23238.161.202.1 to 238.161.203.254238.161.203.255510
231238.161.204.0/23238.161.204.1 to 238.161.205.254238.161.205.255510
232238.161.206.0/23238.161.206.1 to 238.161.207.254238.161.207.255510
233238.161.208.0/23238.161.208.1 to 238.161.209.254238.161.209.255510
234238.161.210.0/23238.161.210.1 to 238.161.211.254238.161.211.255510
235238.161.212.0/23238.161.212.1 to 238.161.213.254238.161.213.255510
236238.161.214.0/23238.161.214.1 to 238.161.215.254238.161.215.255510
237238.161.216.0/23238.161.216.1 to 238.161.217.254238.161.217.255510
238238.161.218.0/23238.161.218.1 to 238.161.219.254238.161.219.255510
239238.161.220.0/23238.161.220.1 to 238.161.221.254238.161.221.255510
240238.161.222.0/23238.161.222.1 to 238.161.223.254238.161.223.255510
241238.161.224.0/23238.161.224.1 to 238.161.225.254238.161.225.255510
242238.161.226.0/23238.161.226.1 to 238.161.227.254238.161.227.255510
243238.161.228.0/23238.161.228.1 to 238.161.229.254238.161.229.255510
244238.161.230.0/23238.161.230.1 to 238.161.231.254238.161.231.255510
245238.161.232.0/23238.161.232.1 to 238.161.233.254238.161.233.255510
246238.161.234.0/23238.161.234.1 to 238.161.235.254238.161.235.255510
247238.161.236.0/23238.161.236.1 to 238.161.237.254238.161.237.255510
248238.161.238.0/23238.161.238.1 to 238.161.239.254238.161.239.255510
249238.161.240.0/23238.161.240.1 to 238.161.241.254238.161.241.255510
250238.161.242.0/23238.161.242.1 to 238.161.243.254238.161.243.255510
251238.161.244.0/23238.161.244.1 to 238.161.245.254238.161.245.255510
252238.161.246.0/23238.161.246.1 to 238.161.247.254238.161.247.255510
253238.161.248.0/23238.161.248.1 to 238.161.249.254238.161.249.255510
254238.161.250.0/23238.161.250.1 to 238.161.251.254238.161.251.255510
255238.161.252.0/23238.161.252.1 to 238.161.253.254238.161.253.255510
256238.161.254.0/23238.161.254.1 to 238.161.255.254238.161.255.255510

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.