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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.

Network230.248.0.0/13
Usable hosts524,286
Subnet mask255.248.0.0
Addresses524,288
Network address
230.248.0.0
Broadcast address
230.255.255.255
First usable
230.248.0.1
Last usable
230.255.255.254
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 E6F80000 · Integer 3875012608 to 3875536895
Reverse DNS zones
248.230.in-addr.arpa
249.230.in-addr.arpa
250.230.in-addr.arpa
251.230.in-addr.arpa
252.230.in-addr.arpa
253.230.in-addr.arpa
254.230.in-addr.arpa
255.230.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
Address11100110.11111000.00000000.00000000230.248.0.0
Subnet mask11111111.11111000.00000000.00000000255.248.0.0
Network11100110.11111000.00000000.00000000230.248.0.0
Broadcast11100110.11111111.11111111.11111111230.255.255.255
Split into smaller subnets/24
/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)

230.248.0.0/13 makes 2,048 subnets of /24; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
1230.248.0.0/24230.248.0.1 to 230.248.0.254230.248.0.255254
2230.248.1.0/24230.248.1.1 to 230.248.1.254230.248.1.255254
3230.248.2.0/24230.248.2.1 to 230.248.2.254230.248.2.255254
4230.248.3.0/24230.248.3.1 to 230.248.3.254230.248.3.255254
5230.248.4.0/24230.248.4.1 to 230.248.4.254230.248.4.255254
6230.248.5.0/24230.248.5.1 to 230.248.5.254230.248.5.255254
7230.248.6.0/24230.248.6.1 to 230.248.6.254230.248.6.255254
8230.248.7.0/24230.248.7.1 to 230.248.7.254230.248.7.255254
9230.248.8.0/24230.248.8.1 to 230.248.8.254230.248.8.255254
10230.248.9.0/24230.248.9.1 to 230.248.9.254230.248.9.255254
11230.248.10.0/24230.248.10.1 to 230.248.10.254230.248.10.255254
12230.248.11.0/24230.248.11.1 to 230.248.11.254230.248.11.255254
13230.248.12.0/24230.248.12.1 to 230.248.12.254230.248.12.255254
14230.248.13.0/24230.248.13.1 to 230.248.13.254230.248.13.255254
15230.248.14.0/24230.248.14.1 to 230.248.14.254230.248.14.255254
16230.248.15.0/24230.248.15.1 to 230.248.15.254230.248.15.255254
17230.248.16.0/24230.248.16.1 to 230.248.16.254230.248.16.255254
18230.248.17.0/24230.248.17.1 to 230.248.17.254230.248.17.255254
19230.248.18.0/24230.248.18.1 to 230.248.18.254230.248.18.255254
20230.248.19.0/24230.248.19.1 to 230.248.19.254230.248.19.255254
21230.248.20.0/24230.248.20.1 to 230.248.20.254230.248.20.255254
22230.248.21.0/24230.248.21.1 to 230.248.21.254230.248.21.255254
23230.248.22.0/24230.248.22.1 to 230.248.22.254230.248.22.255254
24230.248.23.0/24230.248.23.1 to 230.248.23.254230.248.23.255254
25230.248.24.0/24230.248.24.1 to 230.248.24.254230.248.24.255254
26230.248.25.0/24230.248.25.1 to 230.248.25.254230.248.25.255254
27230.248.26.0/24230.248.26.1 to 230.248.26.254230.248.26.255254
28230.248.27.0/24230.248.27.1 to 230.248.27.254230.248.27.255254
29230.248.28.0/24230.248.28.1 to 230.248.28.254230.248.28.255254
30230.248.29.0/24230.248.29.1 to 230.248.29.254230.248.29.255254
31230.248.30.0/24230.248.30.1 to 230.248.30.254230.248.30.255254
32230.248.31.0/24230.248.31.1 to 230.248.31.254230.248.31.255254
33230.248.32.0/24230.248.32.1 to 230.248.32.254230.248.32.255254
34230.248.33.0/24230.248.33.1 to 230.248.33.254230.248.33.255254
35230.248.34.0/24230.248.34.1 to 230.248.34.254230.248.34.255254
36230.248.35.0/24230.248.35.1 to 230.248.35.254230.248.35.255254
37230.248.36.0/24230.248.36.1 to 230.248.36.254230.248.36.255254
38230.248.37.0/24230.248.37.1 to 230.248.37.254230.248.37.255254
39230.248.38.0/24230.248.38.1 to 230.248.38.254230.248.38.255254
40230.248.39.0/24230.248.39.1 to 230.248.39.254230.248.39.255254
41230.248.40.0/24230.248.40.1 to 230.248.40.254230.248.40.255254
42230.248.41.0/24230.248.41.1 to 230.248.41.254230.248.41.255254
43230.248.42.0/24230.248.42.1 to 230.248.42.254230.248.42.255254
44230.248.43.0/24230.248.43.1 to 230.248.43.254230.248.43.255254
45230.248.44.0/24230.248.44.1 to 230.248.44.254230.248.44.255254
46230.248.45.0/24230.248.45.1 to 230.248.45.254230.248.45.255254
47230.248.46.0/24230.248.46.1 to 230.248.46.254230.248.46.255254
48230.248.47.0/24230.248.47.1 to 230.248.47.254230.248.47.255254
49230.248.48.0/24230.248.48.1 to 230.248.48.254230.248.48.255254
50230.248.49.0/24230.248.49.1 to 230.248.49.254230.248.49.255254
51230.248.50.0/24230.248.50.1 to 230.248.50.254230.248.50.255254
52230.248.51.0/24230.248.51.1 to 230.248.51.254230.248.51.255254
53230.248.52.0/24230.248.52.1 to 230.248.52.254230.248.52.255254
54230.248.53.0/24230.248.53.1 to 230.248.53.254230.248.53.255254
55230.248.54.0/24230.248.54.1 to 230.248.54.254230.248.54.255254
56230.248.55.0/24230.248.55.1 to 230.248.55.254230.248.55.255254
57230.248.56.0/24230.248.56.1 to 230.248.56.254230.248.56.255254
58230.248.57.0/24230.248.57.1 to 230.248.57.254230.248.57.255254
59230.248.58.0/24230.248.58.1 to 230.248.58.254230.248.58.255254
60230.248.59.0/24230.248.59.1 to 230.248.59.254230.248.59.255254
61230.248.60.0/24230.248.60.1 to 230.248.60.254230.248.60.255254
62230.248.61.0/24230.248.61.1 to 230.248.61.254230.248.61.255254
63230.248.62.0/24230.248.62.1 to 230.248.62.254230.248.62.255254
64230.248.63.0/24230.248.63.1 to 230.248.63.254230.248.63.255254
65230.248.64.0/24230.248.64.1 to 230.248.64.254230.248.64.255254
66230.248.65.0/24230.248.65.1 to 230.248.65.254230.248.65.255254
67230.248.66.0/24230.248.66.1 to 230.248.66.254230.248.66.255254
68230.248.67.0/24230.248.67.1 to 230.248.67.254230.248.67.255254
69230.248.68.0/24230.248.68.1 to 230.248.68.254230.248.68.255254
70230.248.69.0/24230.248.69.1 to 230.248.69.254230.248.69.255254
71230.248.70.0/24230.248.70.1 to 230.248.70.254230.248.70.255254
72230.248.71.0/24230.248.71.1 to 230.248.71.254230.248.71.255254
73230.248.72.0/24230.248.72.1 to 230.248.72.254230.248.72.255254
74230.248.73.0/24230.248.73.1 to 230.248.73.254230.248.73.255254
75230.248.74.0/24230.248.74.1 to 230.248.74.254230.248.74.255254
76230.248.75.0/24230.248.75.1 to 230.248.75.254230.248.75.255254
77230.248.76.0/24230.248.76.1 to 230.248.76.254230.248.76.255254
78230.248.77.0/24230.248.77.1 to 230.248.77.254230.248.77.255254
79230.248.78.0/24230.248.78.1 to 230.248.78.254230.248.78.255254
80230.248.79.0/24230.248.79.1 to 230.248.79.254230.248.79.255254
81230.248.80.0/24230.248.80.1 to 230.248.80.254230.248.80.255254
82230.248.81.0/24230.248.81.1 to 230.248.81.254230.248.81.255254
83230.248.82.0/24230.248.82.1 to 230.248.82.254230.248.82.255254
84230.248.83.0/24230.248.83.1 to 230.248.83.254230.248.83.255254
85230.248.84.0/24230.248.84.1 to 230.248.84.254230.248.84.255254
86230.248.85.0/24230.248.85.1 to 230.248.85.254230.248.85.255254
87230.248.86.0/24230.248.86.1 to 230.248.86.254230.248.86.255254
88230.248.87.0/24230.248.87.1 to 230.248.87.254230.248.87.255254
89230.248.88.0/24230.248.88.1 to 230.248.88.254230.248.88.255254
90230.248.89.0/24230.248.89.1 to 230.248.89.254230.248.89.255254
91230.248.90.0/24230.248.90.1 to 230.248.90.254230.248.90.255254
92230.248.91.0/24230.248.91.1 to 230.248.91.254230.248.91.255254
93230.248.92.0/24230.248.92.1 to 230.248.92.254230.248.92.255254
94230.248.93.0/24230.248.93.1 to 230.248.93.254230.248.93.255254
95230.248.94.0/24230.248.94.1 to 230.248.94.254230.248.94.255254
96230.248.95.0/24230.248.95.1 to 230.248.95.254230.248.95.255254
97230.248.96.0/24230.248.96.1 to 230.248.96.254230.248.96.255254
98230.248.97.0/24230.248.97.1 to 230.248.97.254230.248.97.255254
99230.248.98.0/24230.248.98.1 to 230.248.98.254230.248.98.255254
100230.248.99.0/24230.248.99.1 to 230.248.99.254230.248.99.255254
101230.248.100.0/24230.248.100.1 to 230.248.100.254230.248.100.255254
102230.248.101.0/24230.248.101.1 to 230.248.101.254230.248.101.255254
103230.248.102.0/24230.248.102.1 to 230.248.102.254230.248.102.255254
104230.248.103.0/24230.248.103.1 to 230.248.103.254230.248.103.255254
105230.248.104.0/24230.248.104.1 to 230.248.104.254230.248.104.255254
106230.248.105.0/24230.248.105.1 to 230.248.105.254230.248.105.255254
107230.248.106.0/24230.248.106.1 to 230.248.106.254230.248.106.255254
108230.248.107.0/24230.248.107.1 to 230.248.107.254230.248.107.255254
109230.248.108.0/24230.248.108.1 to 230.248.108.254230.248.108.255254
110230.248.109.0/24230.248.109.1 to 230.248.109.254230.248.109.255254
111230.248.110.0/24230.248.110.1 to 230.248.110.254230.248.110.255254
112230.248.111.0/24230.248.111.1 to 230.248.111.254230.248.111.255254
113230.248.112.0/24230.248.112.1 to 230.248.112.254230.248.112.255254
114230.248.113.0/24230.248.113.1 to 230.248.113.254230.248.113.255254
115230.248.114.0/24230.248.114.1 to 230.248.114.254230.248.114.255254
116230.248.115.0/24230.248.115.1 to 230.248.115.254230.248.115.255254
117230.248.116.0/24230.248.116.1 to 230.248.116.254230.248.116.255254
118230.248.117.0/24230.248.117.1 to 230.248.117.254230.248.117.255254
119230.248.118.0/24230.248.118.1 to 230.248.118.254230.248.118.255254
120230.248.119.0/24230.248.119.1 to 230.248.119.254230.248.119.255254
121230.248.120.0/24230.248.120.1 to 230.248.120.254230.248.120.255254
122230.248.121.0/24230.248.121.1 to 230.248.121.254230.248.121.255254
123230.248.122.0/24230.248.122.1 to 230.248.122.254230.248.122.255254
124230.248.123.0/24230.248.123.1 to 230.248.123.254230.248.123.255254
125230.248.124.0/24230.248.124.1 to 230.248.124.254230.248.124.255254
126230.248.125.0/24230.248.125.1 to 230.248.125.254230.248.125.255254
127230.248.126.0/24230.248.126.1 to 230.248.126.254230.248.126.255254
128230.248.127.0/24230.248.127.1 to 230.248.127.254230.248.127.255254
129230.248.128.0/24230.248.128.1 to 230.248.128.254230.248.128.255254
130230.248.129.0/24230.248.129.1 to 230.248.129.254230.248.129.255254
131230.248.130.0/24230.248.130.1 to 230.248.130.254230.248.130.255254
132230.248.131.0/24230.248.131.1 to 230.248.131.254230.248.131.255254
133230.248.132.0/24230.248.132.1 to 230.248.132.254230.248.132.255254
134230.248.133.0/24230.248.133.1 to 230.248.133.254230.248.133.255254
135230.248.134.0/24230.248.134.1 to 230.248.134.254230.248.134.255254
136230.248.135.0/24230.248.135.1 to 230.248.135.254230.248.135.255254
137230.248.136.0/24230.248.136.1 to 230.248.136.254230.248.136.255254
138230.248.137.0/24230.248.137.1 to 230.248.137.254230.248.137.255254
139230.248.138.0/24230.248.138.1 to 230.248.138.254230.248.138.255254
140230.248.139.0/24230.248.139.1 to 230.248.139.254230.248.139.255254
141230.248.140.0/24230.248.140.1 to 230.248.140.254230.248.140.255254
142230.248.141.0/24230.248.141.1 to 230.248.141.254230.248.141.255254
143230.248.142.0/24230.248.142.1 to 230.248.142.254230.248.142.255254
144230.248.143.0/24230.248.143.1 to 230.248.143.254230.248.143.255254
145230.248.144.0/24230.248.144.1 to 230.248.144.254230.248.144.255254
146230.248.145.0/24230.248.145.1 to 230.248.145.254230.248.145.255254
147230.248.146.0/24230.248.146.1 to 230.248.146.254230.248.146.255254
148230.248.147.0/24230.248.147.1 to 230.248.147.254230.248.147.255254
149230.248.148.0/24230.248.148.1 to 230.248.148.254230.248.148.255254
150230.248.149.0/24230.248.149.1 to 230.248.149.254230.248.149.255254
151230.248.150.0/24230.248.150.1 to 230.248.150.254230.248.150.255254
152230.248.151.0/24230.248.151.1 to 230.248.151.254230.248.151.255254
153230.248.152.0/24230.248.152.1 to 230.248.152.254230.248.152.255254
154230.248.153.0/24230.248.153.1 to 230.248.153.254230.248.153.255254
155230.248.154.0/24230.248.154.1 to 230.248.154.254230.248.154.255254
156230.248.155.0/24230.248.155.1 to 230.248.155.254230.248.155.255254
157230.248.156.0/24230.248.156.1 to 230.248.156.254230.248.156.255254
158230.248.157.0/24230.248.157.1 to 230.248.157.254230.248.157.255254
159230.248.158.0/24230.248.158.1 to 230.248.158.254230.248.158.255254
160230.248.159.0/24230.248.159.1 to 230.248.159.254230.248.159.255254
161230.248.160.0/24230.248.160.1 to 230.248.160.254230.248.160.255254
162230.248.161.0/24230.248.161.1 to 230.248.161.254230.248.161.255254
163230.248.162.0/24230.248.162.1 to 230.248.162.254230.248.162.255254
164230.248.163.0/24230.248.163.1 to 230.248.163.254230.248.163.255254
165230.248.164.0/24230.248.164.1 to 230.248.164.254230.248.164.255254
166230.248.165.0/24230.248.165.1 to 230.248.165.254230.248.165.255254
167230.248.166.0/24230.248.166.1 to 230.248.166.254230.248.166.255254
168230.248.167.0/24230.248.167.1 to 230.248.167.254230.248.167.255254
169230.248.168.0/24230.248.168.1 to 230.248.168.254230.248.168.255254
170230.248.169.0/24230.248.169.1 to 230.248.169.254230.248.169.255254
171230.248.170.0/24230.248.170.1 to 230.248.170.254230.248.170.255254
172230.248.171.0/24230.248.171.1 to 230.248.171.254230.248.171.255254
173230.248.172.0/24230.248.172.1 to 230.248.172.254230.248.172.255254
174230.248.173.0/24230.248.173.1 to 230.248.173.254230.248.173.255254
175230.248.174.0/24230.248.174.1 to 230.248.174.254230.248.174.255254
176230.248.175.0/24230.248.175.1 to 230.248.175.254230.248.175.255254
177230.248.176.0/24230.248.176.1 to 230.248.176.254230.248.176.255254
178230.248.177.0/24230.248.177.1 to 230.248.177.254230.248.177.255254
179230.248.178.0/24230.248.178.1 to 230.248.178.254230.248.178.255254
180230.248.179.0/24230.248.179.1 to 230.248.179.254230.248.179.255254
181230.248.180.0/24230.248.180.1 to 230.248.180.254230.248.180.255254
182230.248.181.0/24230.248.181.1 to 230.248.181.254230.248.181.255254
183230.248.182.0/24230.248.182.1 to 230.248.182.254230.248.182.255254
184230.248.183.0/24230.248.183.1 to 230.248.183.254230.248.183.255254
185230.248.184.0/24230.248.184.1 to 230.248.184.254230.248.184.255254
186230.248.185.0/24230.248.185.1 to 230.248.185.254230.248.185.255254
187230.248.186.0/24230.248.186.1 to 230.248.186.254230.248.186.255254
188230.248.187.0/24230.248.187.1 to 230.248.187.254230.248.187.255254
189230.248.188.0/24230.248.188.1 to 230.248.188.254230.248.188.255254
190230.248.189.0/24230.248.189.1 to 230.248.189.254230.248.189.255254
191230.248.190.0/24230.248.190.1 to 230.248.190.254230.248.190.255254
192230.248.191.0/24230.248.191.1 to 230.248.191.254230.248.191.255254
193230.248.192.0/24230.248.192.1 to 230.248.192.254230.248.192.255254
194230.248.193.0/24230.248.193.1 to 230.248.193.254230.248.193.255254
195230.248.194.0/24230.248.194.1 to 230.248.194.254230.248.194.255254
196230.248.195.0/24230.248.195.1 to 230.248.195.254230.248.195.255254
197230.248.196.0/24230.248.196.1 to 230.248.196.254230.248.196.255254
198230.248.197.0/24230.248.197.1 to 230.248.197.254230.248.197.255254
199230.248.198.0/24230.248.198.1 to 230.248.198.254230.248.198.255254
200230.248.199.0/24230.248.199.1 to 230.248.199.254230.248.199.255254
201230.248.200.0/24230.248.200.1 to 230.248.200.254230.248.200.255254
202230.248.201.0/24230.248.201.1 to 230.248.201.254230.248.201.255254
203230.248.202.0/24230.248.202.1 to 230.248.202.254230.248.202.255254
204230.248.203.0/24230.248.203.1 to 230.248.203.254230.248.203.255254
205230.248.204.0/24230.248.204.1 to 230.248.204.254230.248.204.255254
206230.248.205.0/24230.248.205.1 to 230.248.205.254230.248.205.255254
207230.248.206.0/24230.248.206.1 to 230.248.206.254230.248.206.255254
208230.248.207.0/24230.248.207.1 to 230.248.207.254230.248.207.255254
209230.248.208.0/24230.248.208.1 to 230.248.208.254230.248.208.255254
210230.248.209.0/24230.248.209.1 to 230.248.209.254230.248.209.255254
211230.248.210.0/24230.248.210.1 to 230.248.210.254230.248.210.255254
212230.248.211.0/24230.248.211.1 to 230.248.211.254230.248.211.255254
213230.248.212.0/24230.248.212.1 to 230.248.212.254230.248.212.255254
214230.248.213.0/24230.248.213.1 to 230.248.213.254230.248.213.255254
215230.248.214.0/24230.248.214.1 to 230.248.214.254230.248.214.255254
216230.248.215.0/24230.248.215.1 to 230.248.215.254230.248.215.255254
217230.248.216.0/24230.248.216.1 to 230.248.216.254230.248.216.255254
218230.248.217.0/24230.248.217.1 to 230.248.217.254230.248.217.255254
219230.248.218.0/24230.248.218.1 to 230.248.218.254230.248.218.255254
220230.248.219.0/24230.248.219.1 to 230.248.219.254230.248.219.255254
221230.248.220.0/24230.248.220.1 to 230.248.220.254230.248.220.255254
222230.248.221.0/24230.248.221.1 to 230.248.221.254230.248.221.255254
223230.248.222.0/24230.248.222.1 to 230.248.222.254230.248.222.255254
224230.248.223.0/24230.248.223.1 to 230.248.223.254230.248.223.255254
225230.248.224.0/24230.248.224.1 to 230.248.224.254230.248.224.255254
226230.248.225.0/24230.248.225.1 to 230.248.225.254230.248.225.255254
227230.248.226.0/24230.248.226.1 to 230.248.226.254230.248.226.255254
228230.248.227.0/24230.248.227.1 to 230.248.227.254230.248.227.255254
229230.248.228.0/24230.248.228.1 to 230.248.228.254230.248.228.255254
230230.248.229.0/24230.248.229.1 to 230.248.229.254230.248.229.255254
231230.248.230.0/24230.248.230.1 to 230.248.230.254230.248.230.255254
232230.248.231.0/24230.248.231.1 to 230.248.231.254230.248.231.255254
233230.248.232.0/24230.248.232.1 to 230.248.232.254230.248.232.255254
234230.248.233.0/24230.248.233.1 to 230.248.233.254230.248.233.255254
235230.248.234.0/24230.248.234.1 to 230.248.234.254230.248.234.255254
236230.248.235.0/24230.248.235.1 to 230.248.235.254230.248.235.255254
237230.248.236.0/24230.248.236.1 to 230.248.236.254230.248.236.255254
238230.248.237.0/24230.248.237.1 to 230.248.237.254230.248.237.255254
239230.248.238.0/24230.248.238.1 to 230.248.238.254230.248.238.255254
240230.248.239.0/24230.248.239.1 to 230.248.239.254230.248.239.255254
241230.248.240.0/24230.248.240.1 to 230.248.240.254230.248.240.255254
242230.248.241.0/24230.248.241.1 to 230.248.241.254230.248.241.255254
243230.248.242.0/24230.248.242.1 to 230.248.242.254230.248.242.255254
244230.248.243.0/24230.248.243.1 to 230.248.243.254230.248.243.255254
245230.248.244.0/24230.248.244.1 to 230.248.244.254230.248.244.255254
246230.248.245.0/24230.248.245.1 to 230.248.245.254230.248.245.255254
247230.248.246.0/24230.248.246.1 to 230.248.246.254230.248.246.255254
248230.248.247.0/24230.248.247.1 to 230.248.247.254230.248.247.255254
249230.248.248.0/24230.248.248.1 to 230.248.248.254230.248.248.255254
250230.248.249.0/24230.248.249.1 to 230.248.249.254230.248.249.255254
251230.248.250.0/24230.248.250.1 to 230.248.250.254230.248.250.255254
252230.248.251.0/24230.248.251.1 to 230.248.251.254230.248.251.255254
253230.248.252.0/24230.248.252.1 to 230.248.252.254230.248.252.255254
254230.248.253.0/24230.248.253.1 to 230.248.253.254230.248.253.255254
255230.248.254.0/24230.248.254.1 to 230.248.254.254230.248.254.255254
256230.248.255.0/24230.248.255.1 to 230.248.255.254230.248.255.255254

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.