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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.

Network228.56.0.0/13
Usable hosts524,286
Subnet mask255.248.0.0
Addresses524,288
Network address
228.56.0.0
Broadcast address
228.63.255.255
First usable
228.56.0.1
Last usable
228.63.255.254
Usable hosts
524,286 (524,288 less the network and broadcast addresses)
Subnet mask
255.248.0.0
Wildcard mask
0.7.255.255 (Cisco ACLs, OSPF)
Prefix length
/13
Type
Multicast 224.0.0.0/4
One-to-many traffic, such as IPTV and routing protocols
Old class
D (multicast)
As numbers
Hex E4380000 · Integer 3828875264 to 3829399551
Reverse DNS zones
56.228.in-addr.arpa
57.228.in-addr.arpa
58.228.in-addr.arpa
59.228.in-addr.arpa
60.228.in-addr.arpa
61.228.in-addr.arpa
62.228.in-addr.arpa
63.228.in-addr.arpa
/13 is not on a 8-bit boundary, so it takes 8 /16 zones.
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address11100100.00111000.00000000.00000000228.56.0.0
Subnet mask11111111.11111000.00000000.00000000255.248.0.0
Network11100100.00111000.00000000.00000000228.56.0.0
Broadcast11100100.00111111.11111111.11111111228.63.255.255
Split into smaller subnets/23
/14 (2)/15 (4)/16 (8)/17 (16)/18 (32)/19 (64)/20 (128)/21 (256)/22 (512)/23 (1,024)/24 (2,048)/25 (4,096)

228.56.0.0/13 makes 1,024 subnets of /23; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
1228.56.0.0/23228.56.0.1 to 228.56.1.254228.56.1.255510
2228.56.2.0/23228.56.2.1 to 228.56.3.254228.56.3.255510
3228.56.4.0/23228.56.4.1 to 228.56.5.254228.56.5.255510
4228.56.6.0/23228.56.6.1 to 228.56.7.254228.56.7.255510
5228.56.8.0/23228.56.8.1 to 228.56.9.254228.56.9.255510
6228.56.10.0/23228.56.10.1 to 228.56.11.254228.56.11.255510
7228.56.12.0/23228.56.12.1 to 228.56.13.254228.56.13.255510
8228.56.14.0/23228.56.14.1 to 228.56.15.254228.56.15.255510
9228.56.16.0/23228.56.16.1 to 228.56.17.254228.56.17.255510
10228.56.18.0/23228.56.18.1 to 228.56.19.254228.56.19.255510
11228.56.20.0/23228.56.20.1 to 228.56.21.254228.56.21.255510
12228.56.22.0/23228.56.22.1 to 228.56.23.254228.56.23.255510
13228.56.24.0/23228.56.24.1 to 228.56.25.254228.56.25.255510
14228.56.26.0/23228.56.26.1 to 228.56.27.254228.56.27.255510
15228.56.28.0/23228.56.28.1 to 228.56.29.254228.56.29.255510
16228.56.30.0/23228.56.30.1 to 228.56.31.254228.56.31.255510
17228.56.32.0/23228.56.32.1 to 228.56.33.254228.56.33.255510
18228.56.34.0/23228.56.34.1 to 228.56.35.254228.56.35.255510
19228.56.36.0/23228.56.36.1 to 228.56.37.254228.56.37.255510
20228.56.38.0/23228.56.38.1 to 228.56.39.254228.56.39.255510
21228.56.40.0/23228.56.40.1 to 228.56.41.254228.56.41.255510
22228.56.42.0/23228.56.42.1 to 228.56.43.254228.56.43.255510
23228.56.44.0/23228.56.44.1 to 228.56.45.254228.56.45.255510
24228.56.46.0/23228.56.46.1 to 228.56.47.254228.56.47.255510
25228.56.48.0/23228.56.48.1 to 228.56.49.254228.56.49.255510
26228.56.50.0/23228.56.50.1 to 228.56.51.254228.56.51.255510
27228.56.52.0/23228.56.52.1 to 228.56.53.254228.56.53.255510
28228.56.54.0/23228.56.54.1 to 228.56.55.254228.56.55.255510
29228.56.56.0/23228.56.56.1 to 228.56.57.254228.56.57.255510
30228.56.58.0/23228.56.58.1 to 228.56.59.254228.56.59.255510
31228.56.60.0/23228.56.60.1 to 228.56.61.254228.56.61.255510
32228.56.62.0/23228.56.62.1 to 228.56.63.254228.56.63.255510
33228.56.64.0/23228.56.64.1 to 228.56.65.254228.56.65.255510
34228.56.66.0/23228.56.66.1 to 228.56.67.254228.56.67.255510
35228.56.68.0/23228.56.68.1 to 228.56.69.254228.56.69.255510
36228.56.70.0/23228.56.70.1 to 228.56.71.254228.56.71.255510
37228.56.72.0/23228.56.72.1 to 228.56.73.254228.56.73.255510
38228.56.74.0/23228.56.74.1 to 228.56.75.254228.56.75.255510
39228.56.76.0/23228.56.76.1 to 228.56.77.254228.56.77.255510
40228.56.78.0/23228.56.78.1 to 228.56.79.254228.56.79.255510
41228.56.80.0/23228.56.80.1 to 228.56.81.254228.56.81.255510
42228.56.82.0/23228.56.82.1 to 228.56.83.254228.56.83.255510
43228.56.84.0/23228.56.84.1 to 228.56.85.254228.56.85.255510
44228.56.86.0/23228.56.86.1 to 228.56.87.254228.56.87.255510
45228.56.88.0/23228.56.88.1 to 228.56.89.254228.56.89.255510
46228.56.90.0/23228.56.90.1 to 228.56.91.254228.56.91.255510
47228.56.92.0/23228.56.92.1 to 228.56.93.254228.56.93.255510
48228.56.94.0/23228.56.94.1 to 228.56.95.254228.56.95.255510
49228.56.96.0/23228.56.96.1 to 228.56.97.254228.56.97.255510
50228.56.98.0/23228.56.98.1 to 228.56.99.254228.56.99.255510
51228.56.100.0/23228.56.100.1 to 228.56.101.254228.56.101.255510
52228.56.102.0/23228.56.102.1 to 228.56.103.254228.56.103.255510
53228.56.104.0/23228.56.104.1 to 228.56.105.254228.56.105.255510
54228.56.106.0/23228.56.106.1 to 228.56.107.254228.56.107.255510
55228.56.108.0/23228.56.108.1 to 228.56.109.254228.56.109.255510
56228.56.110.0/23228.56.110.1 to 228.56.111.254228.56.111.255510
57228.56.112.0/23228.56.112.1 to 228.56.113.254228.56.113.255510
58228.56.114.0/23228.56.114.1 to 228.56.115.254228.56.115.255510
59228.56.116.0/23228.56.116.1 to 228.56.117.254228.56.117.255510
60228.56.118.0/23228.56.118.1 to 228.56.119.254228.56.119.255510
61228.56.120.0/23228.56.120.1 to 228.56.121.254228.56.121.255510
62228.56.122.0/23228.56.122.1 to 228.56.123.254228.56.123.255510
63228.56.124.0/23228.56.124.1 to 228.56.125.254228.56.125.255510
64228.56.126.0/23228.56.126.1 to 228.56.127.254228.56.127.255510
65228.56.128.0/23228.56.128.1 to 228.56.129.254228.56.129.255510
66228.56.130.0/23228.56.130.1 to 228.56.131.254228.56.131.255510
67228.56.132.0/23228.56.132.1 to 228.56.133.254228.56.133.255510
68228.56.134.0/23228.56.134.1 to 228.56.135.254228.56.135.255510
69228.56.136.0/23228.56.136.1 to 228.56.137.254228.56.137.255510
70228.56.138.0/23228.56.138.1 to 228.56.139.254228.56.139.255510
71228.56.140.0/23228.56.140.1 to 228.56.141.254228.56.141.255510
72228.56.142.0/23228.56.142.1 to 228.56.143.254228.56.143.255510
73228.56.144.0/23228.56.144.1 to 228.56.145.254228.56.145.255510
74228.56.146.0/23228.56.146.1 to 228.56.147.254228.56.147.255510
75228.56.148.0/23228.56.148.1 to 228.56.149.254228.56.149.255510
76228.56.150.0/23228.56.150.1 to 228.56.151.254228.56.151.255510
77228.56.152.0/23228.56.152.1 to 228.56.153.254228.56.153.255510
78228.56.154.0/23228.56.154.1 to 228.56.155.254228.56.155.255510
79228.56.156.0/23228.56.156.1 to 228.56.157.254228.56.157.255510
80228.56.158.0/23228.56.158.1 to 228.56.159.254228.56.159.255510
81228.56.160.0/23228.56.160.1 to 228.56.161.254228.56.161.255510
82228.56.162.0/23228.56.162.1 to 228.56.163.254228.56.163.255510
83228.56.164.0/23228.56.164.1 to 228.56.165.254228.56.165.255510
84228.56.166.0/23228.56.166.1 to 228.56.167.254228.56.167.255510
85228.56.168.0/23228.56.168.1 to 228.56.169.254228.56.169.255510
86228.56.170.0/23228.56.170.1 to 228.56.171.254228.56.171.255510
87228.56.172.0/23228.56.172.1 to 228.56.173.254228.56.173.255510
88228.56.174.0/23228.56.174.1 to 228.56.175.254228.56.175.255510
89228.56.176.0/23228.56.176.1 to 228.56.177.254228.56.177.255510
90228.56.178.0/23228.56.178.1 to 228.56.179.254228.56.179.255510
91228.56.180.0/23228.56.180.1 to 228.56.181.254228.56.181.255510
92228.56.182.0/23228.56.182.1 to 228.56.183.254228.56.183.255510
93228.56.184.0/23228.56.184.1 to 228.56.185.254228.56.185.255510
94228.56.186.0/23228.56.186.1 to 228.56.187.254228.56.187.255510
95228.56.188.0/23228.56.188.1 to 228.56.189.254228.56.189.255510
96228.56.190.0/23228.56.190.1 to 228.56.191.254228.56.191.255510
97228.56.192.0/23228.56.192.1 to 228.56.193.254228.56.193.255510
98228.56.194.0/23228.56.194.1 to 228.56.195.254228.56.195.255510
99228.56.196.0/23228.56.196.1 to 228.56.197.254228.56.197.255510
100228.56.198.0/23228.56.198.1 to 228.56.199.254228.56.199.255510
101228.56.200.0/23228.56.200.1 to 228.56.201.254228.56.201.255510
102228.56.202.0/23228.56.202.1 to 228.56.203.254228.56.203.255510
103228.56.204.0/23228.56.204.1 to 228.56.205.254228.56.205.255510
104228.56.206.0/23228.56.206.1 to 228.56.207.254228.56.207.255510
105228.56.208.0/23228.56.208.1 to 228.56.209.254228.56.209.255510
106228.56.210.0/23228.56.210.1 to 228.56.211.254228.56.211.255510
107228.56.212.0/23228.56.212.1 to 228.56.213.254228.56.213.255510
108228.56.214.0/23228.56.214.1 to 228.56.215.254228.56.215.255510
109228.56.216.0/23228.56.216.1 to 228.56.217.254228.56.217.255510
110228.56.218.0/23228.56.218.1 to 228.56.219.254228.56.219.255510
111228.56.220.0/23228.56.220.1 to 228.56.221.254228.56.221.255510
112228.56.222.0/23228.56.222.1 to 228.56.223.254228.56.223.255510
113228.56.224.0/23228.56.224.1 to 228.56.225.254228.56.225.255510
114228.56.226.0/23228.56.226.1 to 228.56.227.254228.56.227.255510
115228.56.228.0/23228.56.228.1 to 228.56.229.254228.56.229.255510
116228.56.230.0/23228.56.230.1 to 228.56.231.254228.56.231.255510
117228.56.232.0/23228.56.232.1 to 228.56.233.254228.56.233.255510
118228.56.234.0/23228.56.234.1 to 228.56.235.254228.56.235.255510
119228.56.236.0/23228.56.236.1 to 228.56.237.254228.56.237.255510
120228.56.238.0/23228.56.238.1 to 228.56.239.254228.56.239.255510
121228.56.240.0/23228.56.240.1 to 228.56.241.254228.56.241.255510
122228.56.242.0/23228.56.242.1 to 228.56.243.254228.56.243.255510
123228.56.244.0/23228.56.244.1 to 228.56.245.254228.56.245.255510
124228.56.246.0/23228.56.246.1 to 228.56.247.254228.56.247.255510
125228.56.248.0/23228.56.248.1 to 228.56.249.254228.56.249.255510
126228.56.250.0/23228.56.250.1 to 228.56.251.254228.56.251.255510
127228.56.252.0/23228.56.252.1 to 228.56.253.254228.56.253.255510
128228.56.254.0/23228.56.254.1 to 228.56.255.254228.56.255.255510
129228.57.0.0/23228.57.0.1 to 228.57.1.254228.57.1.255510
130228.57.2.0/23228.57.2.1 to 228.57.3.254228.57.3.255510
131228.57.4.0/23228.57.4.1 to 228.57.5.254228.57.5.255510
132228.57.6.0/23228.57.6.1 to 228.57.7.254228.57.7.255510
133228.57.8.0/23228.57.8.1 to 228.57.9.254228.57.9.255510
134228.57.10.0/23228.57.10.1 to 228.57.11.254228.57.11.255510
135228.57.12.0/23228.57.12.1 to 228.57.13.254228.57.13.255510
136228.57.14.0/23228.57.14.1 to 228.57.15.254228.57.15.255510
137228.57.16.0/23228.57.16.1 to 228.57.17.254228.57.17.255510
138228.57.18.0/23228.57.18.1 to 228.57.19.254228.57.19.255510
139228.57.20.0/23228.57.20.1 to 228.57.21.254228.57.21.255510
140228.57.22.0/23228.57.22.1 to 228.57.23.254228.57.23.255510
141228.57.24.0/23228.57.24.1 to 228.57.25.254228.57.25.255510
142228.57.26.0/23228.57.26.1 to 228.57.27.254228.57.27.255510
143228.57.28.0/23228.57.28.1 to 228.57.29.254228.57.29.255510
144228.57.30.0/23228.57.30.1 to 228.57.31.254228.57.31.255510
145228.57.32.0/23228.57.32.1 to 228.57.33.254228.57.33.255510
146228.57.34.0/23228.57.34.1 to 228.57.35.254228.57.35.255510
147228.57.36.0/23228.57.36.1 to 228.57.37.254228.57.37.255510
148228.57.38.0/23228.57.38.1 to 228.57.39.254228.57.39.255510
149228.57.40.0/23228.57.40.1 to 228.57.41.254228.57.41.255510
150228.57.42.0/23228.57.42.1 to 228.57.43.254228.57.43.255510
151228.57.44.0/23228.57.44.1 to 228.57.45.254228.57.45.255510
152228.57.46.0/23228.57.46.1 to 228.57.47.254228.57.47.255510
153228.57.48.0/23228.57.48.1 to 228.57.49.254228.57.49.255510
154228.57.50.0/23228.57.50.1 to 228.57.51.254228.57.51.255510
155228.57.52.0/23228.57.52.1 to 228.57.53.254228.57.53.255510
156228.57.54.0/23228.57.54.1 to 228.57.55.254228.57.55.255510
157228.57.56.0/23228.57.56.1 to 228.57.57.254228.57.57.255510
158228.57.58.0/23228.57.58.1 to 228.57.59.254228.57.59.255510
159228.57.60.0/23228.57.60.1 to 228.57.61.254228.57.61.255510
160228.57.62.0/23228.57.62.1 to 228.57.63.254228.57.63.255510
161228.57.64.0/23228.57.64.1 to 228.57.65.254228.57.65.255510
162228.57.66.0/23228.57.66.1 to 228.57.67.254228.57.67.255510
163228.57.68.0/23228.57.68.1 to 228.57.69.254228.57.69.255510
164228.57.70.0/23228.57.70.1 to 228.57.71.254228.57.71.255510
165228.57.72.0/23228.57.72.1 to 228.57.73.254228.57.73.255510
166228.57.74.0/23228.57.74.1 to 228.57.75.254228.57.75.255510
167228.57.76.0/23228.57.76.1 to 228.57.77.254228.57.77.255510
168228.57.78.0/23228.57.78.1 to 228.57.79.254228.57.79.255510
169228.57.80.0/23228.57.80.1 to 228.57.81.254228.57.81.255510
170228.57.82.0/23228.57.82.1 to 228.57.83.254228.57.83.255510
171228.57.84.0/23228.57.84.1 to 228.57.85.254228.57.85.255510
172228.57.86.0/23228.57.86.1 to 228.57.87.254228.57.87.255510
173228.57.88.0/23228.57.88.1 to 228.57.89.254228.57.89.255510
174228.57.90.0/23228.57.90.1 to 228.57.91.254228.57.91.255510
175228.57.92.0/23228.57.92.1 to 228.57.93.254228.57.93.255510
176228.57.94.0/23228.57.94.1 to 228.57.95.254228.57.95.255510
177228.57.96.0/23228.57.96.1 to 228.57.97.254228.57.97.255510
178228.57.98.0/23228.57.98.1 to 228.57.99.254228.57.99.255510
179228.57.100.0/23228.57.100.1 to 228.57.101.254228.57.101.255510
180228.57.102.0/23228.57.102.1 to 228.57.103.254228.57.103.255510
181228.57.104.0/23228.57.104.1 to 228.57.105.254228.57.105.255510
182228.57.106.0/23228.57.106.1 to 228.57.107.254228.57.107.255510
183228.57.108.0/23228.57.108.1 to 228.57.109.254228.57.109.255510
184228.57.110.0/23228.57.110.1 to 228.57.111.254228.57.111.255510
185228.57.112.0/23228.57.112.1 to 228.57.113.254228.57.113.255510
186228.57.114.0/23228.57.114.1 to 228.57.115.254228.57.115.255510
187228.57.116.0/23228.57.116.1 to 228.57.117.254228.57.117.255510
188228.57.118.0/23228.57.118.1 to 228.57.119.254228.57.119.255510
189228.57.120.0/23228.57.120.1 to 228.57.121.254228.57.121.255510
190228.57.122.0/23228.57.122.1 to 228.57.123.254228.57.123.255510
191228.57.124.0/23228.57.124.1 to 228.57.125.254228.57.125.255510
192228.57.126.0/23228.57.126.1 to 228.57.127.254228.57.127.255510
193228.57.128.0/23228.57.128.1 to 228.57.129.254228.57.129.255510
194228.57.130.0/23228.57.130.1 to 228.57.131.254228.57.131.255510
195228.57.132.0/23228.57.132.1 to 228.57.133.254228.57.133.255510
196228.57.134.0/23228.57.134.1 to 228.57.135.254228.57.135.255510
197228.57.136.0/23228.57.136.1 to 228.57.137.254228.57.137.255510
198228.57.138.0/23228.57.138.1 to 228.57.139.254228.57.139.255510
199228.57.140.0/23228.57.140.1 to 228.57.141.254228.57.141.255510
200228.57.142.0/23228.57.142.1 to 228.57.143.254228.57.143.255510
201228.57.144.0/23228.57.144.1 to 228.57.145.254228.57.145.255510
202228.57.146.0/23228.57.146.1 to 228.57.147.254228.57.147.255510
203228.57.148.0/23228.57.148.1 to 228.57.149.254228.57.149.255510
204228.57.150.0/23228.57.150.1 to 228.57.151.254228.57.151.255510
205228.57.152.0/23228.57.152.1 to 228.57.153.254228.57.153.255510
206228.57.154.0/23228.57.154.1 to 228.57.155.254228.57.155.255510
207228.57.156.0/23228.57.156.1 to 228.57.157.254228.57.157.255510
208228.57.158.0/23228.57.158.1 to 228.57.159.254228.57.159.255510
209228.57.160.0/23228.57.160.1 to 228.57.161.254228.57.161.255510
210228.57.162.0/23228.57.162.1 to 228.57.163.254228.57.163.255510
211228.57.164.0/23228.57.164.1 to 228.57.165.254228.57.165.255510
212228.57.166.0/23228.57.166.1 to 228.57.167.254228.57.167.255510
213228.57.168.0/23228.57.168.1 to 228.57.169.254228.57.169.255510
214228.57.170.0/23228.57.170.1 to 228.57.171.254228.57.171.255510
215228.57.172.0/23228.57.172.1 to 228.57.173.254228.57.173.255510
216228.57.174.0/23228.57.174.1 to 228.57.175.254228.57.175.255510
217228.57.176.0/23228.57.176.1 to 228.57.177.254228.57.177.255510
218228.57.178.0/23228.57.178.1 to 228.57.179.254228.57.179.255510
219228.57.180.0/23228.57.180.1 to 228.57.181.254228.57.181.255510
220228.57.182.0/23228.57.182.1 to 228.57.183.254228.57.183.255510
221228.57.184.0/23228.57.184.1 to 228.57.185.254228.57.185.255510
222228.57.186.0/23228.57.186.1 to 228.57.187.254228.57.187.255510
223228.57.188.0/23228.57.188.1 to 228.57.189.254228.57.189.255510
224228.57.190.0/23228.57.190.1 to 228.57.191.254228.57.191.255510
225228.57.192.0/23228.57.192.1 to 228.57.193.254228.57.193.255510
226228.57.194.0/23228.57.194.1 to 228.57.195.254228.57.195.255510
227228.57.196.0/23228.57.196.1 to 228.57.197.254228.57.197.255510
228228.57.198.0/23228.57.198.1 to 228.57.199.254228.57.199.255510
229228.57.200.0/23228.57.200.1 to 228.57.201.254228.57.201.255510
230228.57.202.0/23228.57.202.1 to 228.57.203.254228.57.203.255510
231228.57.204.0/23228.57.204.1 to 228.57.205.254228.57.205.255510
232228.57.206.0/23228.57.206.1 to 228.57.207.254228.57.207.255510
233228.57.208.0/23228.57.208.1 to 228.57.209.254228.57.209.255510
234228.57.210.0/23228.57.210.1 to 228.57.211.254228.57.211.255510
235228.57.212.0/23228.57.212.1 to 228.57.213.254228.57.213.255510
236228.57.214.0/23228.57.214.1 to 228.57.215.254228.57.215.255510
237228.57.216.0/23228.57.216.1 to 228.57.217.254228.57.217.255510
238228.57.218.0/23228.57.218.1 to 228.57.219.254228.57.219.255510
239228.57.220.0/23228.57.220.1 to 228.57.221.254228.57.221.255510
240228.57.222.0/23228.57.222.1 to 228.57.223.254228.57.223.255510
241228.57.224.0/23228.57.224.1 to 228.57.225.254228.57.225.255510
242228.57.226.0/23228.57.226.1 to 228.57.227.254228.57.227.255510
243228.57.228.0/23228.57.228.1 to 228.57.229.254228.57.229.255510
244228.57.230.0/23228.57.230.1 to 228.57.231.254228.57.231.255510
245228.57.232.0/23228.57.232.1 to 228.57.233.254228.57.233.255510
246228.57.234.0/23228.57.234.1 to 228.57.235.254228.57.235.255510
247228.57.236.0/23228.57.236.1 to 228.57.237.254228.57.237.255510
248228.57.238.0/23228.57.238.1 to 228.57.239.254228.57.239.255510
249228.57.240.0/23228.57.240.1 to 228.57.241.254228.57.241.255510
250228.57.242.0/23228.57.242.1 to 228.57.243.254228.57.243.255510
251228.57.244.0/23228.57.244.1 to 228.57.245.254228.57.245.255510
252228.57.246.0/23228.57.246.1 to 228.57.247.254228.57.247.255510
253228.57.248.0/23228.57.248.1 to 228.57.249.254228.57.249.255510
254228.57.250.0/23228.57.250.1 to 228.57.251.254228.57.251.255510
255228.57.252.0/23228.57.252.1 to 228.57.253.254228.57.253.255510
256228.57.254.0/23228.57.254.1 to 228.57.255.254228.57.255.255510

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.