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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.

Network229.0.0.0/11
Usable hosts2,097,150
Subnet mask255.224.0.0
Addresses2,097,152
Network address
229.0.0.0
Broadcast address
229.31.255.255
First usable
229.0.0.1
Last usable
229.31.255.254
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 E5000000 · Integer 3841982464 to 3844079615
Reverse DNS zones
0.229.in-addr.arpa
1.229.in-addr.arpa
2.229.in-addr.arpa
3.229.in-addr.arpa
4.229.in-addr.arpa
5.229.in-addr.arpa
6.229.in-addr.arpa
7.229.in-addr.arpa
8.229.in-addr.arpa
9.229.in-addr.arpa
10.229.in-addr.arpa
11.229.in-addr.arpa
12.229.in-addr.arpa
13.229.in-addr.arpa
14.229.in-addr.arpa
15.229.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
Address11100101.00000000.00000000.00000000229.0.0.0
Subnet mask11111111.11100000.00000000.00000000255.224.0.0
Network11100101.00000000.00000000.00000000229.0.0.0
Broadcast11100101.00011111.11111111.11111111229.31.255.255
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)

229.0.0.0/11 makes 4,096 subnets of /23; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
1229.0.0.0/23229.0.0.1 to 229.0.1.254229.0.1.255510
2229.0.2.0/23229.0.2.1 to 229.0.3.254229.0.3.255510
3229.0.4.0/23229.0.4.1 to 229.0.5.254229.0.5.255510
4229.0.6.0/23229.0.6.1 to 229.0.7.254229.0.7.255510
5229.0.8.0/23229.0.8.1 to 229.0.9.254229.0.9.255510
6229.0.10.0/23229.0.10.1 to 229.0.11.254229.0.11.255510
7229.0.12.0/23229.0.12.1 to 229.0.13.254229.0.13.255510
8229.0.14.0/23229.0.14.1 to 229.0.15.254229.0.15.255510
9229.0.16.0/23229.0.16.1 to 229.0.17.254229.0.17.255510
10229.0.18.0/23229.0.18.1 to 229.0.19.254229.0.19.255510
11229.0.20.0/23229.0.20.1 to 229.0.21.254229.0.21.255510
12229.0.22.0/23229.0.22.1 to 229.0.23.254229.0.23.255510
13229.0.24.0/23229.0.24.1 to 229.0.25.254229.0.25.255510
14229.0.26.0/23229.0.26.1 to 229.0.27.254229.0.27.255510
15229.0.28.0/23229.0.28.1 to 229.0.29.254229.0.29.255510
16229.0.30.0/23229.0.30.1 to 229.0.31.254229.0.31.255510
17229.0.32.0/23229.0.32.1 to 229.0.33.254229.0.33.255510
18229.0.34.0/23229.0.34.1 to 229.0.35.254229.0.35.255510
19229.0.36.0/23229.0.36.1 to 229.0.37.254229.0.37.255510
20229.0.38.0/23229.0.38.1 to 229.0.39.254229.0.39.255510
21229.0.40.0/23229.0.40.1 to 229.0.41.254229.0.41.255510
22229.0.42.0/23229.0.42.1 to 229.0.43.254229.0.43.255510
23229.0.44.0/23229.0.44.1 to 229.0.45.254229.0.45.255510
24229.0.46.0/23229.0.46.1 to 229.0.47.254229.0.47.255510
25229.0.48.0/23229.0.48.1 to 229.0.49.254229.0.49.255510
26229.0.50.0/23229.0.50.1 to 229.0.51.254229.0.51.255510
27229.0.52.0/23229.0.52.1 to 229.0.53.254229.0.53.255510
28229.0.54.0/23229.0.54.1 to 229.0.55.254229.0.55.255510
29229.0.56.0/23229.0.56.1 to 229.0.57.254229.0.57.255510
30229.0.58.0/23229.0.58.1 to 229.0.59.254229.0.59.255510
31229.0.60.0/23229.0.60.1 to 229.0.61.254229.0.61.255510
32229.0.62.0/23229.0.62.1 to 229.0.63.254229.0.63.255510
33229.0.64.0/23229.0.64.1 to 229.0.65.254229.0.65.255510
34229.0.66.0/23229.0.66.1 to 229.0.67.254229.0.67.255510
35229.0.68.0/23229.0.68.1 to 229.0.69.254229.0.69.255510
36229.0.70.0/23229.0.70.1 to 229.0.71.254229.0.71.255510
37229.0.72.0/23229.0.72.1 to 229.0.73.254229.0.73.255510
38229.0.74.0/23229.0.74.1 to 229.0.75.254229.0.75.255510
39229.0.76.0/23229.0.76.1 to 229.0.77.254229.0.77.255510
40229.0.78.0/23229.0.78.1 to 229.0.79.254229.0.79.255510
41229.0.80.0/23229.0.80.1 to 229.0.81.254229.0.81.255510
42229.0.82.0/23229.0.82.1 to 229.0.83.254229.0.83.255510
43229.0.84.0/23229.0.84.1 to 229.0.85.254229.0.85.255510
44229.0.86.0/23229.0.86.1 to 229.0.87.254229.0.87.255510
45229.0.88.0/23229.0.88.1 to 229.0.89.254229.0.89.255510
46229.0.90.0/23229.0.90.1 to 229.0.91.254229.0.91.255510
47229.0.92.0/23229.0.92.1 to 229.0.93.254229.0.93.255510
48229.0.94.0/23229.0.94.1 to 229.0.95.254229.0.95.255510
49229.0.96.0/23229.0.96.1 to 229.0.97.254229.0.97.255510
50229.0.98.0/23229.0.98.1 to 229.0.99.254229.0.99.255510
51229.0.100.0/23229.0.100.1 to 229.0.101.254229.0.101.255510
52229.0.102.0/23229.0.102.1 to 229.0.103.254229.0.103.255510
53229.0.104.0/23229.0.104.1 to 229.0.105.254229.0.105.255510
54229.0.106.0/23229.0.106.1 to 229.0.107.254229.0.107.255510
55229.0.108.0/23229.0.108.1 to 229.0.109.254229.0.109.255510
56229.0.110.0/23229.0.110.1 to 229.0.111.254229.0.111.255510
57229.0.112.0/23229.0.112.1 to 229.0.113.254229.0.113.255510
58229.0.114.0/23229.0.114.1 to 229.0.115.254229.0.115.255510
59229.0.116.0/23229.0.116.1 to 229.0.117.254229.0.117.255510
60229.0.118.0/23229.0.118.1 to 229.0.119.254229.0.119.255510
61229.0.120.0/23229.0.120.1 to 229.0.121.254229.0.121.255510
62229.0.122.0/23229.0.122.1 to 229.0.123.254229.0.123.255510
63229.0.124.0/23229.0.124.1 to 229.0.125.254229.0.125.255510
64229.0.126.0/23229.0.126.1 to 229.0.127.254229.0.127.255510
65229.0.128.0/23229.0.128.1 to 229.0.129.254229.0.129.255510
66229.0.130.0/23229.0.130.1 to 229.0.131.254229.0.131.255510
67229.0.132.0/23229.0.132.1 to 229.0.133.254229.0.133.255510
68229.0.134.0/23229.0.134.1 to 229.0.135.254229.0.135.255510
69229.0.136.0/23229.0.136.1 to 229.0.137.254229.0.137.255510
70229.0.138.0/23229.0.138.1 to 229.0.139.254229.0.139.255510
71229.0.140.0/23229.0.140.1 to 229.0.141.254229.0.141.255510
72229.0.142.0/23229.0.142.1 to 229.0.143.254229.0.143.255510
73229.0.144.0/23229.0.144.1 to 229.0.145.254229.0.145.255510
74229.0.146.0/23229.0.146.1 to 229.0.147.254229.0.147.255510
75229.0.148.0/23229.0.148.1 to 229.0.149.254229.0.149.255510
76229.0.150.0/23229.0.150.1 to 229.0.151.254229.0.151.255510
77229.0.152.0/23229.0.152.1 to 229.0.153.254229.0.153.255510
78229.0.154.0/23229.0.154.1 to 229.0.155.254229.0.155.255510
79229.0.156.0/23229.0.156.1 to 229.0.157.254229.0.157.255510
80229.0.158.0/23229.0.158.1 to 229.0.159.254229.0.159.255510
81229.0.160.0/23229.0.160.1 to 229.0.161.254229.0.161.255510
82229.0.162.0/23229.0.162.1 to 229.0.163.254229.0.163.255510
83229.0.164.0/23229.0.164.1 to 229.0.165.254229.0.165.255510
84229.0.166.0/23229.0.166.1 to 229.0.167.254229.0.167.255510
85229.0.168.0/23229.0.168.1 to 229.0.169.254229.0.169.255510
86229.0.170.0/23229.0.170.1 to 229.0.171.254229.0.171.255510
87229.0.172.0/23229.0.172.1 to 229.0.173.254229.0.173.255510
88229.0.174.0/23229.0.174.1 to 229.0.175.254229.0.175.255510
89229.0.176.0/23229.0.176.1 to 229.0.177.254229.0.177.255510
90229.0.178.0/23229.0.178.1 to 229.0.179.254229.0.179.255510
91229.0.180.0/23229.0.180.1 to 229.0.181.254229.0.181.255510
92229.0.182.0/23229.0.182.1 to 229.0.183.254229.0.183.255510
93229.0.184.0/23229.0.184.1 to 229.0.185.254229.0.185.255510
94229.0.186.0/23229.0.186.1 to 229.0.187.254229.0.187.255510
95229.0.188.0/23229.0.188.1 to 229.0.189.254229.0.189.255510
96229.0.190.0/23229.0.190.1 to 229.0.191.254229.0.191.255510
97229.0.192.0/23229.0.192.1 to 229.0.193.254229.0.193.255510
98229.0.194.0/23229.0.194.1 to 229.0.195.254229.0.195.255510
99229.0.196.0/23229.0.196.1 to 229.0.197.254229.0.197.255510
100229.0.198.0/23229.0.198.1 to 229.0.199.254229.0.199.255510
101229.0.200.0/23229.0.200.1 to 229.0.201.254229.0.201.255510
102229.0.202.0/23229.0.202.1 to 229.0.203.254229.0.203.255510
103229.0.204.0/23229.0.204.1 to 229.0.205.254229.0.205.255510
104229.0.206.0/23229.0.206.1 to 229.0.207.254229.0.207.255510
105229.0.208.0/23229.0.208.1 to 229.0.209.254229.0.209.255510
106229.0.210.0/23229.0.210.1 to 229.0.211.254229.0.211.255510
107229.0.212.0/23229.0.212.1 to 229.0.213.254229.0.213.255510
108229.0.214.0/23229.0.214.1 to 229.0.215.254229.0.215.255510
109229.0.216.0/23229.0.216.1 to 229.0.217.254229.0.217.255510
110229.0.218.0/23229.0.218.1 to 229.0.219.254229.0.219.255510
111229.0.220.0/23229.0.220.1 to 229.0.221.254229.0.221.255510
112229.0.222.0/23229.0.222.1 to 229.0.223.254229.0.223.255510
113229.0.224.0/23229.0.224.1 to 229.0.225.254229.0.225.255510
114229.0.226.0/23229.0.226.1 to 229.0.227.254229.0.227.255510
115229.0.228.0/23229.0.228.1 to 229.0.229.254229.0.229.255510
116229.0.230.0/23229.0.230.1 to 229.0.231.254229.0.231.255510
117229.0.232.0/23229.0.232.1 to 229.0.233.254229.0.233.255510
118229.0.234.0/23229.0.234.1 to 229.0.235.254229.0.235.255510
119229.0.236.0/23229.0.236.1 to 229.0.237.254229.0.237.255510
120229.0.238.0/23229.0.238.1 to 229.0.239.254229.0.239.255510
121229.0.240.0/23229.0.240.1 to 229.0.241.254229.0.241.255510
122229.0.242.0/23229.0.242.1 to 229.0.243.254229.0.243.255510
123229.0.244.0/23229.0.244.1 to 229.0.245.254229.0.245.255510
124229.0.246.0/23229.0.246.1 to 229.0.247.254229.0.247.255510
125229.0.248.0/23229.0.248.1 to 229.0.249.254229.0.249.255510
126229.0.250.0/23229.0.250.1 to 229.0.251.254229.0.251.255510
127229.0.252.0/23229.0.252.1 to 229.0.253.254229.0.253.255510
128229.0.254.0/23229.0.254.1 to 229.0.255.254229.0.255.255510
129229.1.0.0/23229.1.0.1 to 229.1.1.254229.1.1.255510
130229.1.2.0/23229.1.2.1 to 229.1.3.254229.1.3.255510
131229.1.4.0/23229.1.4.1 to 229.1.5.254229.1.5.255510
132229.1.6.0/23229.1.6.1 to 229.1.7.254229.1.7.255510
133229.1.8.0/23229.1.8.1 to 229.1.9.254229.1.9.255510
134229.1.10.0/23229.1.10.1 to 229.1.11.254229.1.11.255510
135229.1.12.0/23229.1.12.1 to 229.1.13.254229.1.13.255510
136229.1.14.0/23229.1.14.1 to 229.1.15.254229.1.15.255510
137229.1.16.0/23229.1.16.1 to 229.1.17.254229.1.17.255510
138229.1.18.0/23229.1.18.1 to 229.1.19.254229.1.19.255510
139229.1.20.0/23229.1.20.1 to 229.1.21.254229.1.21.255510
140229.1.22.0/23229.1.22.1 to 229.1.23.254229.1.23.255510
141229.1.24.0/23229.1.24.1 to 229.1.25.254229.1.25.255510
142229.1.26.0/23229.1.26.1 to 229.1.27.254229.1.27.255510
143229.1.28.0/23229.1.28.1 to 229.1.29.254229.1.29.255510
144229.1.30.0/23229.1.30.1 to 229.1.31.254229.1.31.255510
145229.1.32.0/23229.1.32.1 to 229.1.33.254229.1.33.255510
146229.1.34.0/23229.1.34.1 to 229.1.35.254229.1.35.255510
147229.1.36.0/23229.1.36.1 to 229.1.37.254229.1.37.255510
148229.1.38.0/23229.1.38.1 to 229.1.39.254229.1.39.255510
149229.1.40.0/23229.1.40.1 to 229.1.41.254229.1.41.255510
150229.1.42.0/23229.1.42.1 to 229.1.43.254229.1.43.255510
151229.1.44.0/23229.1.44.1 to 229.1.45.254229.1.45.255510
152229.1.46.0/23229.1.46.1 to 229.1.47.254229.1.47.255510
153229.1.48.0/23229.1.48.1 to 229.1.49.254229.1.49.255510
154229.1.50.0/23229.1.50.1 to 229.1.51.254229.1.51.255510
155229.1.52.0/23229.1.52.1 to 229.1.53.254229.1.53.255510
156229.1.54.0/23229.1.54.1 to 229.1.55.254229.1.55.255510
157229.1.56.0/23229.1.56.1 to 229.1.57.254229.1.57.255510
158229.1.58.0/23229.1.58.1 to 229.1.59.254229.1.59.255510
159229.1.60.0/23229.1.60.1 to 229.1.61.254229.1.61.255510
160229.1.62.0/23229.1.62.1 to 229.1.63.254229.1.63.255510
161229.1.64.0/23229.1.64.1 to 229.1.65.254229.1.65.255510
162229.1.66.0/23229.1.66.1 to 229.1.67.254229.1.67.255510
163229.1.68.0/23229.1.68.1 to 229.1.69.254229.1.69.255510
164229.1.70.0/23229.1.70.1 to 229.1.71.254229.1.71.255510
165229.1.72.0/23229.1.72.1 to 229.1.73.254229.1.73.255510
166229.1.74.0/23229.1.74.1 to 229.1.75.254229.1.75.255510
167229.1.76.0/23229.1.76.1 to 229.1.77.254229.1.77.255510
168229.1.78.0/23229.1.78.1 to 229.1.79.254229.1.79.255510
169229.1.80.0/23229.1.80.1 to 229.1.81.254229.1.81.255510
170229.1.82.0/23229.1.82.1 to 229.1.83.254229.1.83.255510
171229.1.84.0/23229.1.84.1 to 229.1.85.254229.1.85.255510
172229.1.86.0/23229.1.86.1 to 229.1.87.254229.1.87.255510
173229.1.88.0/23229.1.88.1 to 229.1.89.254229.1.89.255510
174229.1.90.0/23229.1.90.1 to 229.1.91.254229.1.91.255510
175229.1.92.0/23229.1.92.1 to 229.1.93.254229.1.93.255510
176229.1.94.0/23229.1.94.1 to 229.1.95.254229.1.95.255510
177229.1.96.0/23229.1.96.1 to 229.1.97.254229.1.97.255510
178229.1.98.0/23229.1.98.1 to 229.1.99.254229.1.99.255510
179229.1.100.0/23229.1.100.1 to 229.1.101.254229.1.101.255510
180229.1.102.0/23229.1.102.1 to 229.1.103.254229.1.103.255510
181229.1.104.0/23229.1.104.1 to 229.1.105.254229.1.105.255510
182229.1.106.0/23229.1.106.1 to 229.1.107.254229.1.107.255510
183229.1.108.0/23229.1.108.1 to 229.1.109.254229.1.109.255510
184229.1.110.0/23229.1.110.1 to 229.1.111.254229.1.111.255510
185229.1.112.0/23229.1.112.1 to 229.1.113.254229.1.113.255510
186229.1.114.0/23229.1.114.1 to 229.1.115.254229.1.115.255510
187229.1.116.0/23229.1.116.1 to 229.1.117.254229.1.117.255510
188229.1.118.0/23229.1.118.1 to 229.1.119.254229.1.119.255510
189229.1.120.0/23229.1.120.1 to 229.1.121.254229.1.121.255510
190229.1.122.0/23229.1.122.1 to 229.1.123.254229.1.123.255510
191229.1.124.0/23229.1.124.1 to 229.1.125.254229.1.125.255510
192229.1.126.0/23229.1.126.1 to 229.1.127.254229.1.127.255510
193229.1.128.0/23229.1.128.1 to 229.1.129.254229.1.129.255510
194229.1.130.0/23229.1.130.1 to 229.1.131.254229.1.131.255510
195229.1.132.0/23229.1.132.1 to 229.1.133.254229.1.133.255510
196229.1.134.0/23229.1.134.1 to 229.1.135.254229.1.135.255510
197229.1.136.0/23229.1.136.1 to 229.1.137.254229.1.137.255510
198229.1.138.0/23229.1.138.1 to 229.1.139.254229.1.139.255510
199229.1.140.0/23229.1.140.1 to 229.1.141.254229.1.141.255510
200229.1.142.0/23229.1.142.1 to 229.1.143.254229.1.143.255510
201229.1.144.0/23229.1.144.1 to 229.1.145.254229.1.145.255510
202229.1.146.0/23229.1.146.1 to 229.1.147.254229.1.147.255510
203229.1.148.0/23229.1.148.1 to 229.1.149.254229.1.149.255510
204229.1.150.0/23229.1.150.1 to 229.1.151.254229.1.151.255510
205229.1.152.0/23229.1.152.1 to 229.1.153.254229.1.153.255510
206229.1.154.0/23229.1.154.1 to 229.1.155.254229.1.155.255510
207229.1.156.0/23229.1.156.1 to 229.1.157.254229.1.157.255510
208229.1.158.0/23229.1.158.1 to 229.1.159.254229.1.159.255510
209229.1.160.0/23229.1.160.1 to 229.1.161.254229.1.161.255510
210229.1.162.0/23229.1.162.1 to 229.1.163.254229.1.163.255510
211229.1.164.0/23229.1.164.1 to 229.1.165.254229.1.165.255510
212229.1.166.0/23229.1.166.1 to 229.1.167.254229.1.167.255510
213229.1.168.0/23229.1.168.1 to 229.1.169.254229.1.169.255510
214229.1.170.0/23229.1.170.1 to 229.1.171.254229.1.171.255510
215229.1.172.0/23229.1.172.1 to 229.1.173.254229.1.173.255510
216229.1.174.0/23229.1.174.1 to 229.1.175.254229.1.175.255510
217229.1.176.0/23229.1.176.1 to 229.1.177.254229.1.177.255510
218229.1.178.0/23229.1.178.1 to 229.1.179.254229.1.179.255510
219229.1.180.0/23229.1.180.1 to 229.1.181.254229.1.181.255510
220229.1.182.0/23229.1.182.1 to 229.1.183.254229.1.183.255510
221229.1.184.0/23229.1.184.1 to 229.1.185.254229.1.185.255510
222229.1.186.0/23229.1.186.1 to 229.1.187.254229.1.187.255510
223229.1.188.0/23229.1.188.1 to 229.1.189.254229.1.189.255510
224229.1.190.0/23229.1.190.1 to 229.1.191.254229.1.191.255510
225229.1.192.0/23229.1.192.1 to 229.1.193.254229.1.193.255510
226229.1.194.0/23229.1.194.1 to 229.1.195.254229.1.195.255510
227229.1.196.0/23229.1.196.1 to 229.1.197.254229.1.197.255510
228229.1.198.0/23229.1.198.1 to 229.1.199.254229.1.199.255510
229229.1.200.0/23229.1.200.1 to 229.1.201.254229.1.201.255510
230229.1.202.0/23229.1.202.1 to 229.1.203.254229.1.203.255510
231229.1.204.0/23229.1.204.1 to 229.1.205.254229.1.205.255510
232229.1.206.0/23229.1.206.1 to 229.1.207.254229.1.207.255510
233229.1.208.0/23229.1.208.1 to 229.1.209.254229.1.209.255510
234229.1.210.0/23229.1.210.1 to 229.1.211.254229.1.211.255510
235229.1.212.0/23229.1.212.1 to 229.1.213.254229.1.213.255510
236229.1.214.0/23229.1.214.1 to 229.1.215.254229.1.215.255510
237229.1.216.0/23229.1.216.1 to 229.1.217.254229.1.217.255510
238229.1.218.0/23229.1.218.1 to 229.1.219.254229.1.219.255510
239229.1.220.0/23229.1.220.1 to 229.1.221.254229.1.221.255510
240229.1.222.0/23229.1.222.1 to 229.1.223.254229.1.223.255510
241229.1.224.0/23229.1.224.1 to 229.1.225.254229.1.225.255510
242229.1.226.0/23229.1.226.1 to 229.1.227.254229.1.227.255510
243229.1.228.0/23229.1.228.1 to 229.1.229.254229.1.229.255510
244229.1.230.0/23229.1.230.1 to 229.1.231.254229.1.231.255510
245229.1.232.0/23229.1.232.1 to 229.1.233.254229.1.233.255510
246229.1.234.0/23229.1.234.1 to 229.1.235.254229.1.235.255510
247229.1.236.0/23229.1.236.1 to 229.1.237.254229.1.237.255510
248229.1.238.0/23229.1.238.1 to 229.1.239.254229.1.239.255510
249229.1.240.0/23229.1.240.1 to 229.1.241.254229.1.241.255510
250229.1.242.0/23229.1.242.1 to 229.1.243.254229.1.243.255510
251229.1.244.0/23229.1.244.1 to 229.1.245.254229.1.245.255510
252229.1.246.0/23229.1.246.1 to 229.1.247.254229.1.247.255510
253229.1.248.0/23229.1.248.1 to 229.1.249.254229.1.249.255510
254229.1.250.0/23229.1.250.1 to 229.1.251.254229.1.251.255510
255229.1.252.0/23229.1.252.1 to 229.1.253.254229.1.253.255510
256229.1.254.0/23229.1.254.1 to 229.1.255.254229.1.255.255510

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.