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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.

Network109.40.0.0/13
Usable hosts524,286
Subnet mask255.248.0.0
Addresses524,288
Network address
109.40.0.0
Broadcast address
109.47.255.255
First usable
109.40.0.1
Last usable
109.47.255.254
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
Public public
Old class
A (default /8)
As numbers
Hex 6D280000 · Integer 1831337984 to 1831862271
Reverse DNS zones
40.109.in-addr.arpa
41.109.in-addr.arpa
42.109.in-addr.arpa
43.109.in-addr.arpa
44.109.in-addr.arpa
45.109.in-addr.arpa
46.109.in-addr.arpa
47.109.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
Address01101101.00101000.00000000.00000000109.40.0.0
Subnet mask11111111.11111000.00000000.00000000255.248.0.0
Network01101101.00101000.00000000.00000000109.40.0.0
Broadcast01101101.00101111.11111111.11111111109.47.255.255
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)

109.40.0.0/13 makes 1,024 subnets of /23; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
1109.40.0.0/23109.40.0.1 to 109.40.1.254109.40.1.255510
2109.40.2.0/23109.40.2.1 to 109.40.3.254109.40.3.255510
3109.40.4.0/23109.40.4.1 to 109.40.5.254109.40.5.255510
4109.40.6.0/23109.40.6.1 to 109.40.7.254109.40.7.255510
5109.40.8.0/23109.40.8.1 to 109.40.9.254109.40.9.255510
6109.40.10.0/23109.40.10.1 to 109.40.11.254109.40.11.255510
7109.40.12.0/23109.40.12.1 to 109.40.13.254109.40.13.255510
8109.40.14.0/23109.40.14.1 to 109.40.15.254109.40.15.255510
9109.40.16.0/23109.40.16.1 to 109.40.17.254109.40.17.255510
10109.40.18.0/23109.40.18.1 to 109.40.19.254109.40.19.255510
11109.40.20.0/23109.40.20.1 to 109.40.21.254109.40.21.255510
12109.40.22.0/23109.40.22.1 to 109.40.23.254109.40.23.255510
13109.40.24.0/23109.40.24.1 to 109.40.25.254109.40.25.255510
14109.40.26.0/23109.40.26.1 to 109.40.27.254109.40.27.255510
15109.40.28.0/23109.40.28.1 to 109.40.29.254109.40.29.255510
16109.40.30.0/23109.40.30.1 to 109.40.31.254109.40.31.255510
17109.40.32.0/23109.40.32.1 to 109.40.33.254109.40.33.255510
18109.40.34.0/23109.40.34.1 to 109.40.35.254109.40.35.255510
19109.40.36.0/23109.40.36.1 to 109.40.37.254109.40.37.255510
20109.40.38.0/23109.40.38.1 to 109.40.39.254109.40.39.255510
21109.40.40.0/23109.40.40.1 to 109.40.41.254109.40.41.255510
22109.40.42.0/23109.40.42.1 to 109.40.43.254109.40.43.255510
23109.40.44.0/23109.40.44.1 to 109.40.45.254109.40.45.255510
24109.40.46.0/23109.40.46.1 to 109.40.47.254109.40.47.255510
25109.40.48.0/23109.40.48.1 to 109.40.49.254109.40.49.255510
26109.40.50.0/23109.40.50.1 to 109.40.51.254109.40.51.255510
27109.40.52.0/23109.40.52.1 to 109.40.53.254109.40.53.255510
28109.40.54.0/23109.40.54.1 to 109.40.55.254109.40.55.255510
29109.40.56.0/23109.40.56.1 to 109.40.57.254109.40.57.255510
30109.40.58.0/23109.40.58.1 to 109.40.59.254109.40.59.255510
31109.40.60.0/23109.40.60.1 to 109.40.61.254109.40.61.255510
32109.40.62.0/23109.40.62.1 to 109.40.63.254109.40.63.255510
33109.40.64.0/23109.40.64.1 to 109.40.65.254109.40.65.255510
34109.40.66.0/23109.40.66.1 to 109.40.67.254109.40.67.255510
35109.40.68.0/23109.40.68.1 to 109.40.69.254109.40.69.255510
36109.40.70.0/23109.40.70.1 to 109.40.71.254109.40.71.255510
37109.40.72.0/23109.40.72.1 to 109.40.73.254109.40.73.255510
38109.40.74.0/23109.40.74.1 to 109.40.75.254109.40.75.255510
39109.40.76.0/23109.40.76.1 to 109.40.77.254109.40.77.255510
40109.40.78.0/23109.40.78.1 to 109.40.79.254109.40.79.255510
41109.40.80.0/23109.40.80.1 to 109.40.81.254109.40.81.255510
42109.40.82.0/23109.40.82.1 to 109.40.83.254109.40.83.255510
43109.40.84.0/23109.40.84.1 to 109.40.85.254109.40.85.255510
44109.40.86.0/23109.40.86.1 to 109.40.87.254109.40.87.255510
45109.40.88.0/23109.40.88.1 to 109.40.89.254109.40.89.255510
46109.40.90.0/23109.40.90.1 to 109.40.91.254109.40.91.255510
47109.40.92.0/23109.40.92.1 to 109.40.93.254109.40.93.255510
48109.40.94.0/23109.40.94.1 to 109.40.95.254109.40.95.255510
49109.40.96.0/23109.40.96.1 to 109.40.97.254109.40.97.255510
50109.40.98.0/23109.40.98.1 to 109.40.99.254109.40.99.255510
51109.40.100.0/23109.40.100.1 to 109.40.101.254109.40.101.255510
52109.40.102.0/23109.40.102.1 to 109.40.103.254109.40.103.255510
53109.40.104.0/23109.40.104.1 to 109.40.105.254109.40.105.255510
54109.40.106.0/23109.40.106.1 to 109.40.107.254109.40.107.255510
55109.40.108.0/23109.40.108.1 to 109.40.109.254109.40.109.255510
56109.40.110.0/23109.40.110.1 to 109.40.111.254109.40.111.255510
57109.40.112.0/23109.40.112.1 to 109.40.113.254109.40.113.255510
58109.40.114.0/23109.40.114.1 to 109.40.115.254109.40.115.255510
59109.40.116.0/23109.40.116.1 to 109.40.117.254109.40.117.255510
60109.40.118.0/23109.40.118.1 to 109.40.119.254109.40.119.255510
61109.40.120.0/23109.40.120.1 to 109.40.121.254109.40.121.255510
62109.40.122.0/23109.40.122.1 to 109.40.123.254109.40.123.255510
63109.40.124.0/23109.40.124.1 to 109.40.125.254109.40.125.255510
64109.40.126.0/23109.40.126.1 to 109.40.127.254109.40.127.255510
65109.40.128.0/23109.40.128.1 to 109.40.129.254109.40.129.255510
66109.40.130.0/23109.40.130.1 to 109.40.131.254109.40.131.255510
67109.40.132.0/23109.40.132.1 to 109.40.133.254109.40.133.255510
68109.40.134.0/23109.40.134.1 to 109.40.135.254109.40.135.255510
69109.40.136.0/23109.40.136.1 to 109.40.137.254109.40.137.255510
70109.40.138.0/23109.40.138.1 to 109.40.139.254109.40.139.255510
71109.40.140.0/23109.40.140.1 to 109.40.141.254109.40.141.255510
72109.40.142.0/23109.40.142.1 to 109.40.143.254109.40.143.255510
73109.40.144.0/23109.40.144.1 to 109.40.145.254109.40.145.255510
74109.40.146.0/23109.40.146.1 to 109.40.147.254109.40.147.255510
75109.40.148.0/23109.40.148.1 to 109.40.149.254109.40.149.255510
76109.40.150.0/23109.40.150.1 to 109.40.151.254109.40.151.255510
77109.40.152.0/23109.40.152.1 to 109.40.153.254109.40.153.255510
78109.40.154.0/23109.40.154.1 to 109.40.155.254109.40.155.255510
79109.40.156.0/23109.40.156.1 to 109.40.157.254109.40.157.255510
80109.40.158.0/23109.40.158.1 to 109.40.159.254109.40.159.255510
81109.40.160.0/23109.40.160.1 to 109.40.161.254109.40.161.255510
82109.40.162.0/23109.40.162.1 to 109.40.163.254109.40.163.255510
83109.40.164.0/23109.40.164.1 to 109.40.165.254109.40.165.255510
84109.40.166.0/23109.40.166.1 to 109.40.167.254109.40.167.255510
85109.40.168.0/23109.40.168.1 to 109.40.169.254109.40.169.255510
86109.40.170.0/23109.40.170.1 to 109.40.171.254109.40.171.255510
87109.40.172.0/23109.40.172.1 to 109.40.173.254109.40.173.255510
88109.40.174.0/23109.40.174.1 to 109.40.175.254109.40.175.255510
89109.40.176.0/23109.40.176.1 to 109.40.177.254109.40.177.255510
90109.40.178.0/23109.40.178.1 to 109.40.179.254109.40.179.255510
91109.40.180.0/23109.40.180.1 to 109.40.181.254109.40.181.255510
92109.40.182.0/23109.40.182.1 to 109.40.183.254109.40.183.255510
93109.40.184.0/23109.40.184.1 to 109.40.185.254109.40.185.255510
94109.40.186.0/23109.40.186.1 to 109.40.187.254109.40.187.255510
95109.40.188.0/23109.40.188.1 to 109.40.189.254109.40.189.255510
96109.40.190.0/23109.40.190.1 to 109.40.191.254109.40.191.255510
97109.40.192.0/23109.40.192.1 to 109.40.193.254109.40.193.255510
98109.40.194.0/23109.40.194.1 to 109.40.195.254109.40.195.255510
99109.40.196.0/23109.40.196.1 to 109.40.197.254109.40.197.255510
100109.40.198.0/23109.40.198.1 to 109.40.199.254109.40.199.255510
101109.40.200.0/23109.40.200.1 to 109.40.201.254109.40.201.255510
102109.40.202.0/23109.40.202.1 to 109.40.203.254109.40.203.255510
103109.40.204.0/23109.40.204.1 to 109.40.205.254109.40.205.255510
104109.40.206.0/23109.40.206.1 to 109.40.207.254109.40.207.255510
105109.40.208.0/23109.40.208.1 to 109.40.209.254109.40.209.255510
106109.40.210.0/23109.40.210.1 to 109.40.211.254109.40.211.255510
107109.40.212.0/23109.40.212.1 to 109.40.213.254109.40.213.255510
108109.40.214.0/23109.40.214.1 to 109.40.215.254109.40.215.255510
109109.40.216.0/23109.40.216.1 to 109.40.217.254109.40.217.255510
110109.40.218.0/23109.40.218.1 to 109.40.219.254109.40.219.255510
111109.40.220.0/23109.40.220.1 to 109.40.221.254109.40.221.255510
112109.40.222.0/23109.40.222.1 to 109.40.223.254109.40.223.255510
113109.40.224.0/23109.40.224.1 to 109.40.225.254109.40.225.255510
114109.40.226.0/23109.40.226.1 to 109.40.227.254109.40.227.255510
115109.40.228.0/23109.40.228.1 to 109.40.229.254109.40.229.255510
116109.40.230.0/23109.40.230.1 to 109.40.231.254109.40.231.255510
117109.40.232.0/23109.40.232.1 to 109.40.233.254109.40.233.255510
118109.40.234.0/23109.40.234.1 to 109.40.235.254109.40.235.255510
119109.40.236.0/23109.40.236.1 to 109.40.237.254109.40.237.255510
120109.40.238.0/23109.40.238.1 to 109.40.239.254109.40.239.255510
121109.40.240.0/23109.40.240.1 to 109.40.241.254109.40.241.255510
122109.40.242.0/23109.40.242.1 to 109.40.243.254109.40.243.255510
123109.40.244.0/23109.40.244.1 to 109.40.245.254109.40.245.255510
124109.40.246.0/23109.40.246.1 to 109.40.247.254109.40.247.255510
125109.40.248.0/23109.40.248.1 to 109.40.249.254109.40.249.255510
126109.40.250.0/23109.40.250.1 to 109.40.251.254109.40.251.255510
127109.40.252.0/23109.40.252.1 to 109.40.253.254109.40.253.255510
128109.40.254.0/23109.40.254.1 to 109.40.255.254109.40.255.255510
129109.41.0.0/23109.41.0.1 to 109.41.1.254109.41.1.255510
130109.41.2.0/23109.41.2.1 to 109.41.3.254109.41.3.255510
131109.41.4.0/23109.41.4.1 to 109.41.5.254109.41.5.255510
132109.41.6.0/23109.41.6.1 to 109.41.7.254109.41.7.255510
133109.41.8.0/23109.41.8.1 to 109.41.9.254109.41.9.255510
134109.41.10.0/23109.41.10.1 to 109.41.11.254109.41.11.255510
135109.41.12.0/23109.41.12.1 to 109.41.13.254109.41.13.255510
136109.41.14.0/23109.41.14.1 to 109.41.15.254109.41.15.255510
137109.41.16.0/23109.41.16.1 to 109.41.17.254109.41.17.255510
138109.41.18.0/23109.41.18.1 to 109.41.19.254109.41.19.255510
139109.41.20.0/23109.41.20.1 to 109.41.21.254109.41.21.255510
140109.41.22.0/23109.41.22.1 to 109.41.23.254109.41.23.255510
141109.41.24.0/23109.41.24.1 to 109.41.25.254109.41.25.255510
142109.41.26.0/23109.41.26.1 to 109.41.27.254109.41.27.255510
143109.41.28.0/23109.41.28.1 to 109.41.29.254109.41.29.255510
144109.41.30.0/23109.41.30.1 to 109.41.31.254109.41.31.255510
145109.41.32.0/23109.41.32.1 to 109.41.33.254109.41.33.255510
146109.41.34.0/23109.41.34.1 to 109.41.35.254109.41.35.255510
147109.41.36.0/23109.41.36.1 to 109.41.37.254109.41.37.255510
148109.41.38.0/23109.41.38.1 to 109.41.39.254109.41.39.255510
149109.41.40.0/23109.41.40.1 to 109.41.41.254109.41.41.255510
150109.41.42.0/23109.41.42.1 to 109.41.43.254109.41.43.255510
151109.41.44.0/23109.41.44.1 to 109.41.45.254109.41.45.255510
152109.41.46.0/23109.41.46.1 to 109.41.47.254109.41.47.255510
153109.41.48.0/23109.41.48.1 to 109.41.49.254109.41.49.255510
154109.41.50.0/23109.41.50.1 to 109.41.51.254109.41.51.255510
155109.41.52.0/23109.41.52.1 to 109.41.53.254109.41.53.255510
156109.41.54.0/23109.41.54.1 to 109.41.55.254109.41.55.255510
157109.41.56.0/23109.41.56.1 to 109.41.57.254109.41.57.255510
158109.41.58.0/23109.41.58.1 to 109.41.59.254109.41.59.255510
159109.41.60.0/23109.41.60.1 to 109.41.61.254109.41.61.255510
160109.41.62.0/23109.41.62.1 to 109.41.63.254109.41.63.255510
161109.41.64.0/23109.41.64.1 to 109.41.65.254109.41.65.255510
162109.41.66.0/23109.41.66.1 to 109.41.67.254109.41.67.255510
163109.41.68.0/23109.41.68.1 to 109.41.69.254109.41.69.255510
164109.41.70.0/23109.41.70.1 to 109.41.71.254109.41.71.255510
165109.41.72.0/23109.41.72.1 to 109.41.73.254109.41.73.255510
166109.41.74.0/23109.41.74.1 to 109.41.75.254109.41.75.255510
167109.41.76.0/23109.41.76.1 to 109.41.77.254109.41.77.255510
168109.41.78.0/23109.41.78.1 to 109.41.79.254109.41.79.255510
169109.41.80.0/23109.41.80.1 to 109.41.81.254109.41.81.255510
170109.41.82.0/23109.41.82.1 to 109.41.83.254109.41.83.255510
171109.41.84.0/23109.41.84.1 to 109.41.85.254109.41.85.255510
172109.41.86.0/23109.41.86.1 to 109.41.87.254109.41.87.255510
173109.41.88.0/23109.41.88.1 to 109.41.89.254109.41.89.255510
174109.41.90.0/23109.41.90.1 to 109.41.91.254109.41.91.255510
175109.41.92.0/23109.41.92.1 to 109.41.93.254109.41.93.255510
176109.41.94.0/23109.41.94.1 to 109.41.95.254109.41.95.255510
177109.41.96.0/23109.41.96.1 to 109.41.97.254109.41.97.255510
178109.41.98.0/23109.41.98.1 to 109.41.99.254109.41.99.255510
179109.41.100.0/23109.41.100.1 to 109.41.101.254109.41.101.255510
180109.41.102.0/23109.41.102.1 to 109.41.103.254109.41.103.255510
181109.41.104.0/23109.41.104.1 to 109.41.105.254109.41.105.255510
182109.41.106.0/23109.41.106.1 to 109.41.107.254109.41.107.255510
183109.41.108.0/23109.41.108.1 to 109.41.109.254109.41.109.255510
184109.41.110.0/23109.41.110.1 to 109.41.111.254109.41.111.255510
185109.41.112.0/23109.41.112.1 to 109.41.113.254109.41.113.255510
186109.41.114.0/23109.41.114.1 to 109.41.115.254109.41.115.255510
187109.41.116.0/23109.41.116.1 to 109.41.117.254109.41.117.255510
188109.41.118.0/23109.41.118.1 to 109.41.119.254109.41.119.255510
189109.41.120.0/23109.41.120.1 to 109.41.121.254109.41.121.255510
190109.41.122.0/23109.41.122.1 to 109.41.123.254109.41.123.255510
191109.41.124.0/23109.41.124.1 to 109.41.125.254109.41.125.255510
192109.41.126.0/23109.41.126.1 to 109.41.127.254109.41.127.255510
193109.41.128.0/23109.41.128.1 to 109.41.129.254109.41.129.255510
194109.41.130.0/23109.41.130.1 to 109.41.131.254109.41.131.255510
195109.41.132.0/23109.41.132.1 to 109.41.133.254109.41.133.255510
196109.41.134.0/23109.41.134.1 to 109.41.135.254109.41.135.255510
197109.41.136.0/23109.41.136.1 to 109.41.137.254109.41.137.255510
198109.41.138.0/23109.41.138.1 to 109.41.139.254109.41.139.255510
199109.41.140.0/23109.41.140.1 to 109.41.141.254109.41.141.255510
200109.41.142.0/23109.41.142.1 to 109.41.143.254109.41.143.255510
201109.41.144.0/23109.41.144.1 to 109.41.145.254109.41.145.255510
202109.41.146.0/23109.41.146.1 to 109.41.147.254109.41.147.255510
203109.41.148.0/23109.41.148.1 to 109.41.149.254109.41.149.255510
204109.41.150.0/23109.41.150.1 to 109.41.151.254109.41.151.255510
205109.41.152.0/23109.41.152.1 to 109.41.153.254109.41.153.255510
206109.41.154.0/23109.41.154.1 to 109.41.155.254109.41.155.255510
207109.41.156.0/23109.41.156.1 to 109.41.157.254109.41.157.255510
208109.41.158.0/23109.41.158.1 to 109.41.159.254109.41.159.255510
209109.41.160.0/23109.41.160.1 to 109.41.161.254109.41.161.255510
210109.41.162.0/23109.41.162.1 to 109.41.163.254109.41.163.255510
211109.41.164.0/23109.41.164.1 to 109.41.165.254109.41.165.255510
212109.41.166.0/23109.41.166.1 to 109.41.167.254109.41.167.255510
213109.41.168.0/23109.41.168.1 to 109.41.169.254109.41.169.255510
214109.41.170.0/23109.41.170.1 to 109.41.171.254109.41.171.255510
215109.41.172.0/23109.41.172.1 to 109.41.173.254109.41.173.255510
216109.41.174.0/23109.41.174.1 to 109.41.175.254109.41.175.255510
217109.41.176.0/23109.41.176.1 to 109.41.177.254109.41.177.255510
218109.41.178.0/23109.41.178.1 to 109.41.179.254109.41.179.255510
219109.41.180.0/23109.41.180.1 to 109.41.181.254109.41.181.255510
220109.41.182.0/23109.41.182.1 to 109.41.183.254109.41.183.255510
221109.41.184.0/23109.41.184.1 to 109.41.185.254109.41.185.255510
222109.41.186.0/23109.41.186.1 to 109.41.187.254109.41.187.255510
223109.41.188.0/23109.41.188.1 to 109.41.189.254109.41.189.255510
224109.41.190.0/23109.41.190.1 to 109.41.191.254109.41.191.255510
225109.41.192.0/23109.41.192.1 to 109.41.193.254109.41.193.255510
226109.41.194.0/23109.41.194.1 to 109.41.195.254109.41.195.255510
227109.41.196.0/23109.41.196.1 to 109.41.197.254109.41.197.255510
228109.41.198.0/23109.41.198.1 to 109.41.199.254109.41.199.255510
229109.41.200.0/23109.41.200.1 to 109.41.201.254109.41.201.255510
230109.41.202.0/23109.41.202.1 to 109.41.203.254109.41.203.255510
231109.41.204.0/23109.41.204.1 to 109.41.205.254109.41.205.255510
232109.41.206.0/23109.41.206.1 to 109.41.207.254109.41.207.255510
233109.41.208.0/23109.41.208.1 to 109.41.209.254109.41.209.255510
234109.41.210.0/23109.41.210.1 to 109.41.211.254109.41.211.255510
235109.41.212.0/23109.41.212.1 to 109.41.213.254109.41.213.255510
236109.41.214.0/23109.41.214.1 to 109.41.215.254109.41.215.255510
237109.41.216.0/23109.41.216.1 to 109.41.217.254109.41.217.255510
238109.41.218.0/23109.41.218.1 to 109.41.219.254109.41.219.255510
239109.41.220.0/23109.41.220.1 to 109.41.221.254109.41.221.255510
240109.41.222.0/23109.41.222.1 to 109.41.223.254109.41.223.255510
241109.41.224.0/23109.41.224.1 to 109.41.225.254109.41.225.255510
242109.41.226.0/23109.41.226.1 to 109.41.227.254109.41.227.255510
243109.41.228.0/23109.41.228.1 to 109.41.229.254109.41.229.255510
244109.41.230.0/23109.41.230.1 to 109.41.231.254109.41.231.255510
245109.41.232.0/23109.41.232.1 to 109.41.233.254109.41.233.255510
246109.41.234.0/23109.41.234.1 to 109.41.235.254109.41.235.255510
247109.41.236.0/23109.41.236.1 to 109.41.237.254109.41.237.255510
248109.41.238.0/23109.41.238.1 to 109.41.239.254109.41.239.255510
249109.41.240.0/23109.41.240.1 to 109.41.241.254109.41.241.255510
250109.41.242.0/23109.41.242.1 to 109.41.243.254109.41.243.255510
251109.41.244.0/23109.41.244.1 to 109.41.245.254109.41.245.255510
252109.41.246.0/23109.41.246.1 to 109.41.247.254109.41.247.255510
253109.41.248.0/23109.41.248.1 to 109.41.249.254109.41.249.255510
254109.41.250.0/23109.41.250.1 to 109.41.251.254109.41.251.255510
255109.41.252.0/23109.41.252.1 to 109.41.253.254109.41.253.255510
256109.41.254.0/23109.41.254.1 to 109.41.255.254109.41.255.255510

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.