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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.

Network235.224.0.0/11
Usable hosts2,097,150
Subnet mask255.224.0.0
Addresses2,097,152
Network address
235.224.0.0
Broadcast address
235.255.255.255
First usable
235.224.0.1
Last usable
235.255.255.254
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 EBE00000 · Integer 3957325824 to 3959422975
Reverse DNS zones
224.235.in-addr.arpa
225.235.in-addr.arpa
226.235.in-addr.arpa
227.235.in-addr.arpa
228.235.in-addr.arpa
229.235.in-addr.arpa
230.235.in-addr.arpa
231.235.in-addr.arpa
232.235.in-addr.arpa
233.235.in-addr.arpa
234.235.in-addr.arpa
235.235.in-addr.arpa
236.235.in-addr.arpa
237.235.in-addr.arpa
238.235.in-addr.arpa
239.235.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
Address11101011.11100000.00000000.00000000235.224.0.0
Subnet mask11111111.11100000.00000000.00000000255.224.0.0
Network11101011.11100000.00000000.00000000235.224.0.0
Broadcast11101011.11111111.11111111.11111111235.255.255.255
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)

235.224.0.0/11 makes 4,096 subnets of /23; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
1235.224.0.0/23235.224.0.1 to 235.224.1.254235.224.1.255510
2235.224.2.0/23235.224.2.1 to 235.224.3.254235.224.3.255510
3235.224.4.0/23235.224.4.1 to 235.224.5.254235.224.5.255510
4235.224.6.0/23235.224.6.1 to 235.224.7.254235.224.7.255510
5235.224.8.0/23235.224.8.1 to 235.224.9.254235.224.9.255510
6235.224.10.0/23235.224.10.1 to 235.224.11.254235.224.11.255510
7235.224.12.0/23235.224.12.1 to 235.224.13.254235.224.13.255510
8235.224.14.0/23235.224.14.1 to 235.224.15.254235.224.15.255510
9235.224.16.0/23235.224.16.1 to 235.224.17.254235.224.17.255510
10235.224.18.0/23235.224.18.1 to 235.224.19.254235.224.19.255510
11235.224.20.0/23235.224.20.1 to 235.224.21.254235.224.21.255510
12235.224.22.0/23235.224.22.1 to 235.224.23.254235.224.23.255510
13235.224.24.0/23235.224.24.1 to 235.224.25.254235.224.25.255510
14235.224.26.0/23235.224.26.1 to 235.224.27.254235.224.27.255510
15235.224.28.0/23235.224.28.1 to 235.224.29.254235.224.29.255510
16235.224.30.0/23235.224.30.1 to 235.224.31.254235.224.31.255510
17235.224.32.0/23235.224.32.1 to 235.224.33.254235.224.33.255510
18235.224.34.0/23235.224.34.1 to 235.224.35.254235.224.35.255510
19235.224.36.0/23235.224.36.1 to 235.224.37.254235.224.37.255510
20235.224.38.0/23235.224.38.1 to 235.224.39.254235.224.39.255510
21235.224.40.0/23235.224.40.1 to 235.224.41.254235.224.41.255510
22235.224.42.0/23235.224.42.1 to 235.224.43.254235.224.43.255510
23235.224.44.0/23235.224.44.1 to 235.224.45.254235.224.45.255510
24235.224.46.0/23235.224.46.1 to 235.224.47.254235.224.47.255510
25235.224.48.0/23235.224.48.1 to 235.224.49.254235.224.49.255510
26235.224.50.0/23235.224.50.1 to 235.224.51.254235.224.51.255510
27235.224.52.0/23235.224.52.1 to 235.224.53.254235.224.53.255510
28235.224.54.0/23235.224.54.1 to 235.224.55.254235.224.55.255510
29235.224.56.0/23235.224.56.1 to 235.224.57.254235.224.57.255510
30235.224.58.0/23235.224.58.1 to 235.224.59.254235.224.59.255510
31235.224.60.0/23235.224.60.1 to 235.224.61.254235.224.61.255510
32235.224.62.0/23235.224.62.1 to 235.224.63.254235.224.63.255510
33235.224.64.0/23235.224.64.1 to 235.224.65.254235.224.65.255510
34235.224.66.0/23235.224.66.1 to 235.224.67.254235.224.67.255510
35235.224.68.0/23235.224.68.1 to 235.224.69.254235.224.69.255510
36235.224.70.0/23235.224.70.1 to 235.224.71.254235.224.71.255510
37235.224.72.0/23235.224.72.1 to 235.224.73.254235.224.73.255510
38235.224.74.0/23235.224.74.1 to 235.224.75.254235.224.75.255510
39235.224.76.0/23235.224.76.1 to 235.224.77.254235.224.77.255510
40235.224.78.0/23235.224.78.1 to 235.224.79.254235.224.79.255510
41235.224.80.0/23235.224.80.1 to 235.224.81.254235.224.81.255510
42235.224.82.0/23235.224.82.1 to 235.224.83.254235.224.83.255510
43235.224.84.0/23235.224.84.1 to 235.224.85.254235.224.85.255510
44235.224.86.0/23235.224.86.1 to 235.224.87.254235.224.87.255510
45235.224.88.0/23235.224.88.1 to 235.224.89.254235.224.89.255510
46235.224.90.0/23235.224.90.1 to 235.224.91.254235.224.91.255510
47235.224.92.0/23235.224.92.1 to 235.224.93.254235.224.93.255510
48235.224.94.0/23235.224.94.1 to 235.224.95.254235.224.95.255510
49235.224.96.0/23235.224.96.1 to 235.224.97.254235.224.97.255510
50235.224.98.0/23235.224.98.1 to 235.224.99.254235.224.99.255510
51235.224.100.0/23235.224.100.1 to 235.224.101.254235.224.101.255510
52235.224.102.0/23235.224.102.1 to 235.224.103.254235.224.103.255510
53235.224.104.0/23235.224.104.1 to 235.224.105.254235.224.105.255510
54235.224.106.0/23235.224.106.1 to 235.224.107.254235.224.107.255510
55235.224.108.0/23235.224.108.1 to 235.224.109.254235.224.109.255510
56235.224.110.0/23235.224.110.1 to 235.224.111.254235.224.111.255510
57235.224.112.0/23235.224.112.1 to 235.224.113.254235.224.113.255510
58235.224.114.0/23235.224.114.1 to 235.224.115.254235.224.115.255510
59235.224.116.0/23235.224.116.1 to 235.224.117.254235.224.117.255510
60235.224.118.0/23235.224.118.1 to 235.224.119.254235.224.119.255510
61235.224.120.0/23235.224.120.1 to 235.224.121.254235.224.121.255510
62235.224.122.0/23235.224.122.1 to 235.224.123.254235.224.123.255510
63235.224.124.0/23235.224.124.1 to 235.224.125.254235.224.125.255510
64235.224.126.0/23235.224.126.1 to 235.224.127.254235.224.127.255510
65235.224.128.0/23235.224.128.1 to 235.224.129.254235.224.129.255510
66235.224.130.0/23235.224.130.1 to 235.224.131.254235.224.131.255510
67235.224.132.0/23235.224.132.1 to 235.224.133.254235.224.133.255510
68235.224.134.0/23235.224.134.1 to 235.224.135.254235.224.135.255510
69235.224.136.0/23235.224.136.1 to 235.224.137.254235.224.137.255510
70235.224.138.0/23235.224.138.1 to 235.224.139.254235.224.139.255510
71235.224.140.0/23235.224.140.1 to 235.224.141.254235.224.141.255510
72235.224.142.0/23235.224.142.1 to 235.224.143.254235.224.143.255510
73235.224.144.0/23235.224.144.1 to 235.224.145.254235.224.145.255510
74235.224.146.0/23235.224.146.1 to 235.224.147.254235.224.147.255510
75235.224.148.0/23235.224.148.1 to 235.224.149.254235.224.149.255510
76235.224.150.0/23235.224.150.1 to 235.224.151.254235.224.151.255510
77235.224.152.0/23235.224.152.1 to 235.224.153.254235.224.153.255510
78235.224.154.0/23235.224.154.1 to 235.224.155.254235.224.155.255510
79235.224.156.0/23235.224.156.1 to 235.224.157.254235.224.157.255510
80235.224.158.0/23235.224.158.1 to 235.224.159.254235.224.159.255510
81235.224.160.0/23235.224.160.1 to 235.224.161.254235.224.161.255510
82235.224.162.0/23235.224.162.1 to 235.224.163.254235.224.163.255510
83235.224.164.0/23235.224.164.1 to 235.224.165.254235.224.165.255510
84235.224.166.0/23235.224.166.1 to 235.224.167.254235.224.167.255510
85235.224.168.0/23235.224.168.1 to 235.224.169.254235.224.169.255510
86235.224.170.0/23235.224.170.1 to 235.224.171.254235.224.171.255510
87235.224.172.0/23235.224.172.1 to 235.224.173.254235.224.173.255510
88235.224.174.0/23235.224.174.1 to 235.224.175.254235.224.175.255510
89235.224.176.0/23235.224.176.1 to 235.224.177.254235.224.177.255510
90235.224.178.0/23235.224.178.1 to 235.224.179.254235.224.179.255510
91235.224.180.0/23235.224.180.1 to 235.224.181.254235.224.181.255510
92235.224.182.0/23235.224.182.1 to 235.224.183.254235.224.183.255510
93235.224.184.0/23235.224.184.1 to 235.224.185.254235.224.185.255510
94235.224.186.0/23235.224.186.1 to 235.224.187.254235.224.187.255510
95235.224.188.0/23235.224.188.1 to 235.224.189.254235.224.189.255510
96235.224.190.0/23235.224.190.1 to 235.224.191.254235.224.191.255510
97235.224.192.0/23235.224.192.1 to 235.224.193.254235.224.193.255510
98235.224.194.0/23235.224.194.1 to 235.224.195.254235.224.195.255510
99235.224.196.0/23235.224.196.1 to 235.224.197.254235.224.197.255510
100235.224.198.0/23235.224.198.1 to 235.224.199.254235.224.199.255510
101235.224.200.0/23235.224.200.1 to 235.224.201.254235.224.201.255510
102235.224.202.0/23235.224.202.1 to 235.224.203.254235.224.203.255510
103235.224.204.0/23235.224.204.1 to 235.224.205.254235.224.205.255510
104235.224.206.0/23235.224.206.1 to 235.224.207.254235.224.207.255510
105235.224.208.0/23235.224.208.1 to 235.224.209.254235.224.209.255510
106235.224.210.0/23235.224.210.1 to 235.224.211.254235.224.211.255510
107235.224.212.0/23235.224.212.1 to 235.224.213.254235.224.213.255510
108235.224.214.0/23235.224.214.1 to 235.224.215.254235.224.215.255510
109235.224.216.0/23235.224.216.1 to 235.224.217.254235.224.217.255510
110235.224.218.0/23235.224.218.1 to 235.224.219.254235.224.219.255510
111235.224.220.0/23235.224.220.1 to 235.224.221.254235.224.221.255510
112235.224.222.0/23235.224.222.1 to 235.224.223.254235.224.223.255510
113235.224.224.0/23235.224.224.1 to 235.224.225.254235.224.225.255510
114235.224.226.0/23235.224.226.1 to 235.224.227.254235.224.227.255510
115235.224.228.0/23235.224.228.1 to 235.224.229.254235.224.229.255510
116235.224.230.0/23235.224.230.1 to 235.224.231.254235.224.231.255510
117235.224.232.0/23235.224.232.1 to 235.224.233.254235.224.233.255510
118235.224.234.0/23235.224.234.1 to 235.224.235.254235.224.235.255510
119235.224.236.0/23235.224.236.1 to 235.224.237.254235.224.237.255510
120235.224.238.0/23235.224.238.1 to 235.224.239.254235.224.239.255510
121235.224.240.0/23235.224.240.1 to 235.224.241.254235.224.241.255510
122235.224.242.0/23235.224.242.1 to 235.224.243.254235.224.243.255510
123235.224.244.0/23235.224.244.1 to 235.224.245.254235.224.245.255510
124235.224.246.0/23235.224.246.1 to 235.224.247.254235.224.247.255510
125235.224.248.0/23235.224.248.1 to 235.224.249.254235.224.249.255510
126235.224.250.0/23235.224.250.1 to 235.224.251.254235.224.251.255510
127235.224.252.0/23235.224.252.1 to 235.224.253.254235.224.253.255510
128235.224.254.0/23235.224.254.1 to 235.224.255.254235.224.255.255510
129235.225.0.0/23235.225.0.1 to 235.225.1.254235.225.1.255510
130235.225.2.0/23235.225.2.1 to 235.225.3.254235.225.3.255510
131235.225.4.0/23235.225.4.1 to 235.225.5.254235.225.5.255510
132235.225.6.0/23235.225.6.1 to 235.225.7.254235.225.7.255510
133235.225.8.0/23235.225.8.1 to 235.225.9.254235.225.9.255510
134235.225.10.0/23235.225.10.1 to 235.225.11.254235.225.11.255510
135235.225.12.0/23235.225.12.1 to 235.225.13.254235.225.13.255510
136235.225.14.0/23235.225.14.1 to 235.225.15.254235.225.15.255510
137235.225.16.0/23235.225.16.1 to 235.225.17.254235.225.17.255510
138235.225.18.0/23235.225.18.1 to 235.225.19.254235.225.19.255510
139235.225.20.0/23235.225.20.1 to 235.225.21.254235.225.21.255510
140235.225.22.0/23235.225.22.1 to 235.225.23.254235.225.23.255510
141235.225.24.0/23235.225.24.1 to 235.225.25.254235.225.25.255510
142235.225.26.0/23235.225.26.1 to 235.225.27.254235.225.27.255510
143235.225.28.0/23235.225.28.1 to 235.225.29.254235.225.29.255510
144235.225.30.0/23235.225.30.1 to 235.225.31.254235.225.31.255510
145235.225.32.0/23235.225.32.1 to 235.225.33.254235.225.33.255510
146235.225.34.0/23235.225.34.1 to 235.225.35.254235.225.35.255510
147235.225.36.0/23235.225.36.1 to 235.225.37.254235.225.37.255510
148235.225.38.0/23235.225.38.1 to 235.225.39.254235.225.39.255510
149235.225.40.0/23235.225.40.1 to 235.225.41.254235.225.41.255510
150235.225.42.0/23235.225.42.1 to 235.225.43.254235.225.43.255510
151235.225.44.0/23235.225.44.1 to 235.225.45.254235.225.45.255510
152235.225.46.0/23235.225.46.1 to 235.225.47.254235.225.47.255510
153235.225.48.0/23235.225.48.1 to 235.225.49.254235.225.49.255510
154235.225.50.0/23235.225.50.1 to 235.225.51.254235.225.51.255510
155235.225.52.0/23235.225.52.1 to 235.225.53.254235.225.53.255510
156235.225.54.0/23235.225.54.1 to 235.225.55.254235.225.55.255510
157235.225.56.0/23235.225.56.1 to 235.225.57.254235.225.57.255510
158235.225.58.0/23235.225.58.1 to 235.225.59.254235.225.59.255510
159235.225.60.0/23235.225.60.1 to 235.225.61.254235.225.61.255510
160235.225.62.0/23235.225.62.1 to 235.225.63.254235.225.63.255510
161235.225.64.0/23235.225.64.1 to 235.225.65.254235.225.65.255510
162235.225.66.0/23235.225.66.1 to 235.225.67.254235.225.67.255510
163235.225.68.0/23235.225.68.1 to 235.225.69.254235.225.69.255510
164235.225.70.0/23235.225.70.1 to 235.225.71.254235.225.71.255510
165235.225.72.0/23235.225.72.1 to 235.225.73.254235.225.73.255510
166235.225.74.0/23235.225.74.1 to 235.225.75.254235.225.75.255510
167235.225.76.0/23235.225.76.1 to 235.225.77.254235.225.77.255510
168235.225.78.0/23235.225.78.1 to 235.225.79.254235.225.79.255510
169235.225.80.0/23235.225.80.1 to 235.225.81.254235.225.81.255510
170235.225.82.0/23235.225.82.1 to 235.225.83.254235.225.83.255510
171235.225.84.0/23235.225.84.1 to 235.225.85.254235.225.85.255510
172235.225.86.0/23235.225.86.1 to 235.225.87.254235.225.87.255510
173235.225.88.0/23235.225.88.1 to 235.225.89.254235.225.89.255510
174235.225.90.0/23235.225.90.1 to 235.225.91.254235.225.91.255510
175235.225.92.0/23235.225.92.1 to 235.225.93.254235.225.93.255510
176235.225.94.0/23235.225.94.1 to 235.225.95.254235.225.95.255510
177235.225.96.0/23235.225.96.1 to 235.225.97.254235.225.97.255510
178235.225.98.0/23235.225.98.1 to 235.225.99.254235.225.99.255510
179235.225.100.0/23235.225.100.1 to 235.225.101.254235.225.101.255510
180235.225.102.0/23235.225.102.1 to 235.225.103.254235.225.103.255510
181235.225.104.0/23235.225.104.1 to 235.225.105.254235.225.105.255510
182235.225.106.0/23235.225.106.1 to 235.225.107.254235.225.107.255510
183235.225.108.0/23235.225.108.1 to 235.225.109.254235.225.109.255510
184235.225.110.0/23235.225.110.1 to 235.225.111.254235.225.111.255510
185235.225.112.0/23235.225.112.1 to 235.225.113.254235.225.113.255510
186235.225.114.0/23235.225.114.1 to 235.225.115.254235.225.115.255510
187235.225.116.0/23235.225.116.1 to 235.225.117.254235.225.117.255510
188235.225.118.0/23235.225.118.1 to 235.225.119.254235.225.119.255510
189235.225.120.0/23235.225.120.1 to 235.225.121.254235.225.121.255510
190235.225.122.0/23235.225.122.1 to 235.225.123.254235.225.123.255510
191235.225.124.0/23235.225.124.1 to 235.225.125.254235.225.125.255510
192235.225.126.0/23235.225.126.1 to 235.225.127.254235.225.127.255510
193235.225.128.0/23235.225.128.1 to 235.225.129.254235.225.129.255510
194235.225.130.0/23235.225.130.1 to 235.225.131.254235.225.131.255510
195235.225.132.0/23235.225.132.1 to 235.225.133.254235.225.133.255510
196235.225.134.0/23235.225.134.1 to 235.225.135.254235.225.135.255510
197235.225.136.0/23235.225.136.1 to 235.225.137.254235.225.137.255510
198235.225.138.0/23235.225.138.1 to 235.225.139.254235.225.139.255510
199235.225.140.0/23235.225.140.1 to 235.225.141.254235.225.141.255510
200235.225.142.0/23235.225.142.1 to 235.225.143.254235.225.143.255510
201235.225.144.0/23235.225.144.1 to 235.225.145.254235.225.145.255510
202235.225.146.0/23235.225.146.1 to 235.225.147.254235.225.147.255510
203235.225.148.0/23235.225.148.1 to 235.225.149.254235.225.149.255510
204235.225.150.0/23235.225.150.1 to 235.225.151.254235.225.151.255510
205235.225.152.0/23235.225.152.1 to 235.225.153.254235.225.153.255510
206235.225.154.0/23235.225.154.1 to 235.225.155.254235.225.155.255510
207235.225.156.0/23235.225.156.1 to 235.225.157.254235.225.157.255510
208235.225.158.0/23235.225.158.1 to 235.225.159.254235.225.159.255510
209235.225.160.0/23235.225.160.1 to 235.225.161.254235.225.161.255510
210235.225.162.0/23235.225.162.1 to 235.225.163.254235.225.163.255510
211235.225.164.0/23235.225.164.1 to 235.225.165.254235.225.165.255510
212235.225.166.0/23235.225.166.1 to 235.225.167.254235.225.167.255510
213235.225.168.0/23235.225.168.1 to 235.225.169.254235.225.169.255510
214235.225.170.0/23235.225.170.1 to 235.225.171.254235.225.171.255510
215235.225.172.0/23235.225.172.1 to 235.225.173.254235.225.173.255510
216235.225.174.0/23235.225.174.1 to 235.225.175.254235.225.175.255510
217235.225.176.0/23235.225.176.1 to 235.225.177.254235.225.177.255510
218235.225.178.0/23235.225.178.1 to 235.225.179.254235.225.179.255510
219235.225.180.0/23235.225.180.1 to 235.225.181.254235.225.181.255510
220235.225.182.0/23235.225.182.1 to 235.225.183.254235.225.183.255510
221235.225.184.0/23235.225.184.1 to 235.225.185.254235.225.185.255510
222235.225.186.0/23235.225.186.1 to 235.225.187.254235.225.187.255510
223235.225.188.0/23235.225.188.1 to 235.225.189.254235.225.189.255510
224235.225.190.0/23235.225.190.1 to 235.225.191.254235.225.191.255510
225235.225.192.0/23235.225.192.1 to 235.225.193.254235.225.193.255510
226235.225.194.0/23235.225.194.1 to 235.225.195.254235.225.195.255510
227235.225.196.0/23235.225.196.1 to 235.225.197.254235.225.197.255510
228235.225.198.0/23235.225.198.1 to 235.225.199.254235.225.199.255510
229235.225.200.0/23235.225.200.1 to 235.225.201.254235.225.201.255510
230235.225.202.0/23235.225.202.1 to 235.225.203.254235.225.203.255510
231235.225.204.0/23235.225.204.1 to 235.225.205.254235.225.205.255510
232235.225.206.0/23235.225.206.1 to 235.225.207.254235.225.207.255510
233235.225.208.0/23235.225.208.1 to 235.225.209.254235.225.209.255510
234235.225.210.0/23235.225.210.1 to 235.225.211.254235.225.211.255510
235235.225.212.0/23235.225.212.1 to 235.225.213.254235.225.213.255510
236235.225.214.0/23235.225.214.1 to 235.225.215.254235.225.215.255510
237235.225.216.0/23235.225.216.1 to 235.225.217.254235.225.217.255510
238235.225.218.0/23235.225.218.1 to 235.225.219.254235.225.219.255510
239235.225.220.0/23235.225.220.1 to 235.225.221.254235.225.221.255510
240235.225.222.0/23235.225.222.1 to 235.225.223.254235.225.223.255510
241235.225.224.0/23235.225.224.1 to 235.225.225.254235.225.225.255510
242235.225.226.0/23235.225.226.1 to 235.225.227.254235.225.227.255510
243235.225.228.0/23235.225.228.1 to 235.225.229.254235.225.229.255510
244235.225.230.0/23235.225.230.1 to 235.225.231.254235.225.231.255510
245235.225.232.0/23235.225.232.1 to 235.225.233.254235.225.233.255510
246235.225.234.0/23235.225.234.1 to 235.225.235.254235.225.235.255510
247235.225.236.0/23235.225.236.1 to 235.225.237.254235.225.237.255510
248235.225.238.0/23235.225.238.1 to 235.225.239.254235.225.239.255510
249235.225.240.0/23235.225.240.1 to 235.225.241.254235.225.241.255510
250235.225.242.0/23235.225.242.1 to 235.225.243.254235.225.243.255510
251235.225.244.0/23235.225.244.1 to 235.225.245.254235.225.245.255510
252235.225.246.0/23235.225.246.1 to 235.225.247.254235.225.247.255510
253235.225.248.0/23235.225.248.1 to 235.225.249.254235.225.249.255510
254235.225.250.0/23235.225.250.1 to 235.225.251.254235.225.251.255510
255235.225.252.0/23235.225.252.1 to 235.225.253.254235.225.253.255510
256235.225.254.0/23235.225.254.1 to 235.225.255.254235.225.255.255510

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.