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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.

Network226.160.0.0/13
Usable hosts524,286
Subnet mask255.248.0.0
Addresses524,288
Network address
226.160.0.0
Broadcast address
226.167.255.255
First usable
226.160.0.1
Last usable
226.167.255.254
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 E2A00000 · Integer 3802136576 to 3802660863
Reverse DNS zones
160.226.in-addr.arpa
161.226.in-addr.arpa
162.226.in-addr.arpa
163.226.in-addr.arpa
164.226.in-addr.arpa
165.226.in-addr.arpa
166.226.in-addr.arpa
167.226.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
Address11100010.10100000.00000000.00000000226.160.0.0
Subnet mask11111111.11111000.00000000.00000000255.248.0.0
Network11100010.10100000.00000000.00000000226.160.0.0
Broadcast11100010.10100111.11111111.11111111226.167.255.255
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)

226.160.0.0/13 makes 2,048 subnets of /24; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
1226.160.0.0/24226.160.0.1 to 226.160.0.254226.160.0.255254
2226.160.1.0/24226.160.1.1 to 226.160.1.254226.160.1.255254
3226.160.2.0/24226.160.2.1 to 226.160.2.254226.160.2.255254
4226.160.3.0/24226.160.3.1 to 226.160.3.254226.160.3.255254
5226.160.4.0/24226.160.4.1 to 226.160.4.254226.160.4.255254
6226.160.5.0/24226.160.5.1 to 226.160.5.254226.160.5.255254
7226.160.6.0/24226.160.6.1 to 226.160.6.254226.160.6.255254
8226.160.7.0/24226.160.7.1 to 226.160.7.254226.160.7.255254
9226.160.8.0/24226.160.8.1 to 226.160.8.254226.160.8.255254
10226.160.9.0/24226.160.9.1 to 226.160.9.254226.160.9.255254
11226.160.10.0/24226.160.10.1 to 226.160.10.254226.160.10.255254
12226.160.11.0/24226.160.11.1 to 226.160.11.254226.160.11.255254
13226.160.12.0/24226.160.12.1 to 226.160.12.254226.160.12.255254
14226.160.13.0/24226.160.13.1 to 226.160.13.254226.160.13.255254
15226.160.14.0/24226.160.14.1 to 226.160.14.254226.160.14.255254
16226.160.15.0/24226.160.15.1 to 226.160.15.254226.160.15.255254
17226.160.16.0/24226.160.16.1 to 226.160.16.254226.160.16.255254
18226.160.17.0/24226.160.17.1 to 226.160.17.254226.160.17.255254
19226.160.18.0/24226.160.18.1 to 226.160.18.254226.160.18.255254
20226.160.19.0/24226.160.19.1 to 226.160.19.254226.160.19.255254
21226.160.20.0/24226.160.20.1 to 226.160.20.254226.160.20.255254
22226.160.21.0/24226.160.21.1 to 226.160.21.254226.160.21.255254
23226.160.22.0/24226.160.22.1 to 226.160.22.254226.160.22.255254
24226.160.23.0/24226.160.23.1 to 226.160.23.254226.160.23.255254
25226.160.24.0/24226.160.24.1 to 226.160.24.254226.160.24.255254
26226.160.25.0/24226.160.25.1 to 226.160.25.254226.160.25.255254
27226.160.26.0/24226.160.26.1 to 226.160.26.254226.160.26.255254
28226.160.27.0/24226.160.27.1 to 226.160.27.254226.160.27.255254
29226.160.28.0/24226.160.28.1 to 226.160.28.254226.160.28.255254
30226.160.29.0/24226.160.29.1 to 226.160.29.254226.160.29.255254
31226.160.30.0/24226.160.30.1 to 226.160.30.254226.160.30.255254
32226.160.31.0/24226.160.31.1 to 226.160.31.254226.160.31.255254
33226.160.32.0/24226.160.32.1 to 226.160.32.254226.160.32.255254
34226.160.33.0/24226.160.33.1 to 226.160.33.254226.160.33.255254
35226.160.34.0/24226.160.34.1 to 226.160.34.254226.160.34.255254
36226.160.35.0/24226.160.35.1 to 226.160.35.254226.160.35.255254
37226.160.36.0/24226.160.36.1 to 226.160.36.254226.160.36.255254
38226.160.37.0/24226.160.37.1 to 226.160.37.254226.160.37.255254
39226.160.38.0/24226.160.38.1 to 226.160.38.254226.160.38.255254
40226.160.39.0/24226.160.39.1 to 226.160.39.254226.160.39.255254
41226.160.40.0/24226.160.40.1 to 226.160.40.254226.160.40.255254
42226.160.41.0/24226.160.41.1 to 226.160.41.254226.160.41.255254
43226.160.42.0/24226.160.42.1 to 226.160.42.254226.160.42.255254
44226.160.43.0/24226.160.43.1 to 226.160.43.254226.160.43.255254
45226.160.44.0/24226.160.44.1 to 226.160.44.254226.160.44.255254
46226.160.45.0/24226.160.45.1 to 226.160.45.254226.160.45.255254
47226.160.46.0/24226.160.46.1 to 226.160.46.254226.160.46.255254
48226.160.47.0/24226.160.47.1 to 226.160.47.254226.160.47.255254
49226.160.48.0/24226.160.48.1 to 226.160.48.254226.160.48.255254
50226.160.49.0/24226.160.49.1 to 226.160.49.254226.160.49.255254
51226.160.50.0/24226.160.50.1 to 226.160.50.254226.160.50.255254
52226.160.51.0/24226.160.51.1 to 226.160.51.254226.160.51.255254
53226.160.52.0/24226.160.52.1 to 226.160.52.254226.160.52.255254
54226.160.53.0/24226.160.53.1 to 226.160.53.254226.160.53.255254
55226.160.54.0/24226.160.54.1 to 226.160.54.254226.160.54.255254
56226.160.55.0/24226.160.55.1 to 226.160.55.254226.160.55.255254
57226.160.56.0/24226.160.56.1 to 226.160.56.254226.160.56.255254
58226.160.57.0/24226.160.57.1 to 226.160.57.254226.160.57.255254
59226.160.58.0/24226.160.58.1 to 226.160.58.254226.160.58.255254
60226.160.59.0/24226.160.59.1 to 226.160.59.254226.160.59.255254
61226.160.60.0/24226.160.60.1 to 226.160.60.254226.160.60.255254
62226.160.61.0/24226.160.61.1 to 226.160.61.254226.160.61.255254
63226.160.62.0/24226.160.62.1 to 226.160.62.254226.160.62.255254
64226.160.63.0/24226.160.63.1 to 226.160.63.254226.160.63.255254
65226.160.64.0/24226.160.64.1 to 226.160.64.254226.160.64.255254
66226.160.65.0/24226.160.65.1 to 226.160.65.254226.160.65.255254
67226.160.66.0/24226.160.66.1 to 226.160.66.254226.160.66.255254
68226.160.67.0/24226.160.67.1 to 226.160.67.254226.160.67.255254
69226.160.68.0/24226.160.68.1 to 226.160.68.254226.160.68.255254
70226.160.69.0/24226.160.69.1 to 226.160.69.254226.160.69.255254
71226.160.70.0/24226.160.70.1 to 226.160.70.254226.160.70.255254
72226.160.71.0/24226.160.71.1 to 226.160.71.254226.160.71.255254
73226.160.72.0/24226.160.72.1 to 226.160.72.254226.160.72.255254
74226.160.73.0/24226.160.73.1 to 226.160.73.254226.160.73.255254
75226.160.74.0/24226.160.74.1 to 226.160.74.254226.160.74.255254
76226.160.75.0/24226.160.75.1 to 226.160.75.254226.160.75.255254
77226.160.76.0/24226.160.76.1 to 226.160.76.254226.160.76.255254
78226.160.77.0/24226.160.77.1 to 226.160.77.254226.160.77.255254
79226.160.78.0/24226.160.78.1 to 226.160.78.254226.160.78.255254
80226.160.79.0/24226.160.79.1 to 226.160.79.254226.160.79.255254
81226.160.80.0/24226.160.80.1 to 226.160.80.254226.160.80.255254
82226.160.81.0/24226.160.81.1 to 226.160.81.254226.160.81.255254
83226.160.82.0/24226.160.82.1 to 226.160.82.254226.160.82.255254
84226.160.83.0/24226.160.83.1 to 226.160.83.254226.160.83.255254
85226.160.84.0/24226.160.84.1 to 226.160.84.254226.160.84.255254
86226.160.85.0/24226.160.85.1 to 226.160.85.254226.160.85.255254
87226.160.86.0/24226.160.86.1 to 226.160.86.254226.160.86.255254
88226.160.87.0/24226.160.87.1 to 226.160.87.254226.160.87.255254
89226.160.88.0/24226.160.88.1 to 226.160.88.254226.160.88.255254
90226.160.89.0/24226.160.89.1 to 226.160.89.254226.160.89.255254
91226.160.90.0/24226.160.90.1 to 226.160.90.254226.160.90.255254
92226.160.91.0/24226.160.91.1 to 226.160.91.254226.160.91.255254
93226.160.92.0/24226.160.92.1 to 226.160.92.254226.160.92.255254
94226.160.93.0/24226.160.93.1 to 226.160.93.254226.160.93.255254
95226.160.94.0/24226.160.94.1 to 226.160.94.254226.160.94.255254
96226.160.95.0/24226.160.95.1 to 226.160.95.254226.160.95.255254
97226.160.96.0/24226.160.96.1 to 226.160.96.254226.160.96.255254
98226.160.97.0/24226.160.97.1 to 226.160.97.254226.160.97.255254
99226.160.98.0/24226.160.98.1 to 226.160.98.254226.160.98.255254
100226.160.99.0/24226.160.99.1 to 226.160.99.254226.160.99.255254
101226.160.100.0/24226.160.100.1 to 226.160.100.254226.160.100.255254
102226.160.101.0/24226.160.101.1 to 226.160.101.254226.160.101.255254
103226.160.102.0/24226.160.102.1 to 226.160.102.254226.160.102.255254
104226.160.103.0/24226.160.103.1 to 226.160.103.254226.160.103.255254
105226.160.104.0/24226.160.104.1 to 226.160.104.254226.160.104.255254
106226.160.105.0/24226.160.105.1 to 226.160.105.254226.160.105.255254
107226.160.106.0/24226.160.106.1 to 226.160.106.254226.160.106.255254
108226.160.107.0/24226.160.107.1 to 226.160.107.254226.160.107.255254
109226.160.108.0/24226.160.108.1 to 226.160.108.254226.160.108.255254
110226.160.109.0/24226.160.109.1 to 226.160.109.254226.160.109.255254
111226.160.110.0/24226.160.110.1 to 226.160.110.254226.160.110.255254
112226.160.111.0/24226.160.111.1 to 226.160.111.254226.160.111.255254
113226.160.112.0/24226.160.112.1 to 226.160.112.254226.160.112.255254
114226.160.113.0/24226.160.113.1 to 226.160.113.254226.160.113.255254
115226.160.114.0/24226.160.114.1 to 226.160.114.254226.160.114.255254
116226.160.115.0/24226.160.115.1 to 226.160.115.254226.160.115.255254
117226.160.116.0/24226.160.116.1 to 226.160.116.254226.160.116.255254
118226.160.117.0/24226.160.117.1 to 226.160.117.254226.160.117.255254
119226.160.118.0/24226.160.118.1 to 226.160.118.254226.160.118.255254
120226.160.119.0/24226.160.119.1 to 226.160.119.254226.160.119.255254
121226.160.120.0/24226.160.120.1 to 226.160.120.254226.160.120.255254
122226.160.121.0/24226.160.121.1 to 226.160.121.254226.160.121.255254
123226.160.122.0/24226.160.122.1 to 226.160.122.254226.160.122.255254
124226.160.123.0/24226.160.123.1 to 226.160.123.254226.160.123.255254
125226.160.124.0/24226.160.124.1 to 226.160.124.254226.160.124.255254
126226.160.125.0/24226.160.125.1 to 226.160.125.254226.160.125.255254
127226.160.126.0/24226.160.126.1 to 226.160.126.254226.160.126.255254
128226.160.127.0/24226.160.127.1 to 226.160.127.254226.160.127.255254
129226.160.128.0/24226.160.128.1 to 226.160.128.254226.160.128.255254
130226.160.129.0/24226.160.129.1 to 226.160.129.254226.160.129.255254
131226.160.130.0/24226.160.130.1 to 226.160.130.254226.160.130.255254
132226.160.131.0/24226.160.131.1 to 226.160.131.254226.160.131.255254
133226.160.132.0/24226.160.132.1 to 226.160.132.254226.160.132.255254
134226.160.133.0/24226.160.133.1 to 226.160.133.254226.160.133.255254
135226.160.134.0/24226.160.134.1 to 226.160.134.254226.160.134.255254
136226.160.135.0/24226.160.135.1 to 226.160.135.254226.160.135.255254
137226.160.136.0/24226.160.136.1 to 226.160.136.254226.160.136.255254
138226.160.137.0/24226.160.137.1 to 226.160.137.254226.160.137.255254
139226.160.138.0/24226.160.138.1 to 226.160.138.254226.160.138.255254
140226.160.139.0/24226.160.139.1 to 226.160.139.254226.160.139.255254
141226.160.140.0/24226.160.140.1 to 226.160.140.254226.160.140.255254
142226.160.141.0/24226.160.141.1 to 226.160.141.254226.160.141.255254
143226.160.142.0/24226.160.142.1 to 226.160.142.254226.160.142.255254
144226.160.143.0/24226.160.143.1 to 226.160.143.254226.160.143.255254
145226.160.144.0/24226.160.144.1 to 226.160.144.254226.160.144.255254
146226.160.145.0/24226.160.145.1 to 226.160.145.254226.160.145.255254
147226.160.146.0/24226.160.146.1 to 226.160.146.254226.160.146.255254
148226.160.147.0/24226.160.147.1 to 226.160.147.254226.160.147.255254
149226.160.148.0/24226.160.148.1 to 226.160.148.254226.160.148.255254
150226.160.149.0/24226.160.149.1 to 226.160.149.254226.160.149.255254
151226.160.150.0/24226.160.150.1 to 226.160.150.254226.160.150.255254
152226.160.151.0/24226.160.151.1 to 226.160.151.254226.160.151.255254
153226.160.152.0/24226.160.152.1 to 226.160.152.254226.160.152.255254
154226.160.153.0/24226.160.153.1 to 226.160.153.254226.160.153.255254
155226.160.154.0/24226.160.154.1 to 226.160.154.254226.160.154.255254
156226.160.155.0/24226.160.155.1 to 226.160.155.254226.160.155.255254
157226.160.156.0/24226.160.156.1 to 226.160.156.254226.160.156.255254
158226.160.157.0/24226.160.157.1 to 226.160.157.254226.160.157.255254
159226.160.158.0/24226.160.158.1 to 226.160.158.254226.160.158.255254
160226.160.159.0/24226.160.159.1 to 226.160.159.254226.160.159.255254
161226.160.160.0/24226.160.160.1 to 226.160.160.254226.160.160.255254
162226.160.161.0/24226.160.161.1 to 226.160.161.254226.160.161.255254
163226.160.162.0/24226.160.162.1 to 226.160.162.254226.160.162.255254
164226.160.163.0/24226.160.163.1 to 226.160.163.254226.160.163.255254
165226.160.164.0/24226.160.164.1 to 226.160.164.254226.160.164.255254
166226.160.165.0/24226.160.165.1 to 226.160.165.254226.160.165.255254
167226.160.166.0/24226.160.166.1 to 226.160.166.254226.160.166.255254
168226.160.167.0/24226.160.167.1 to 226.160.167.254226.160.167.255254
169226.160.168.0/24226.160.168.1 to 226.160.168.254226.160.168.255254
170226.160.169.0/24226.160.169.1 to 226.160.169.254226.160.169.255254
171226.160.170.0/24226.160.170.1 to 226.160.170.254226.160.170.255254
172226.160.171.0/24226.160.171.1 to 226.160.171.254226.160.171.255254
173226.160.172.0/24226.160.172.1 to 226.160.172.254226.160.172.255254
174226.160.173.0/24226.160.173.1 to 226.160.173.254226.160.173.255254
175226.160.174.0/24226.160.174.1 to 226.160.174.254226.160.174.255254
176226.160.175.0/24226.160.175.1 to 226.160.175.254226.160.175.255254
177226.160.176.0/24226.160.176.1 to 226.160.176.254226.160.176.255254
178226.160.177.0/24226.160.177.1 to 226.160.177.254226.160.177.255254
179226.160.178.0/24226.160.178.1 to 226.160.178.254226.160.178.255254
180226.160.179.0/24226.160.179.1 to 226.160.179.254226.160.179.255254
181226.160.180.0/24226.160.180.1 to 226.160.180.254226.160.180.255254
182226.160.181.0/24226.160.181.1 to 226.160.181.254226.160.181.255254
183226.160.182.0/24226.160.182.1 to 226.160.182.254226.160.182.255254
184226.160.183.0/24226.160.183.1 to 226.160.183.254226.160.183.255254
185226.160.184.0/24226.160.184.1 to 226.160.184.254226.160.184.255254
186226.160.185.0/24226.160.185.1 to 226.160.185.254226.160.185.255254
187226.160.186.0/24226.160.186.1 to 226.160.186.254226.160.186.255254
188226.160.187.0/24226.160.187.1 to 226.160.187.254226.160.187.255254
189226.160.188.0/24226.160.188.1 to 226.160.188.254226.160.188.255254
190226.160.189.0/24226.160.189.1 to 226.160.189.254226.160.189.255254
191226.160.190.0/24226.160.190.1 to 226.160.190.254226.160.190.255254
192226.160.191.0/24226.160.191.1 to 226.160.191.254226.160.191.255254
193226.160.192.0/24226.160.192.1 to 226.160.192.254226.160.192.255254
194226.160.193.0/24226.160.193.1 to 226.160.193.254226.160.193.255254
195226.160.194.0/24226.160.194.1 to 226.160.194.254226.160.194.255254
196226.160.195.0/24226.160.195.1 to 226.160.195.254226.160.195.255254
197226.160.196.0/24226.160.196.1 to 226.160.196.254226.160.196.255254
198226.160.197.0/24226.160.197.1 to 226.160.197.254226.160.197.255254
199226.160.198.0/24226.160.198.1 to 226.160.198.254226.160.198.255254
200226.160.199.0/24226.160.199.1 to 226.160.199.254226.160.199.255254
201226.160.200.0/24226.160.200.1 to 226.160.200.254226.160.200.255254
202226.160.201.0/24226.160.201.1 to 226.160.201.254226.160.201.255254
203226.160.202.0/24226.160.202.1 to 226.160.202.254226.160.202.255254
204226.160.203.0/24226.160.203.1 to 226.160.203.254226.160.203.255254
205226.160.204.0/24226.160.204.1 to 226.160.204.254226.160.204.255254
206226.160.205.0/24226.160.205.1 to 226.160.205.254226.160.205.255254
207226.160.206.0/24226.160.206.1 to 226.160.206.254226.160.206.255254
208226.160.207.0/24226.160.207.1 to 226.160.207.254226.160.207.255254
209226.160.208.0/24226.160.208.1 to 226.160.208.254226.160.208.255254
210226.160.209.0/24226.160.209.1 to 226.160.209.254226.160.209.255254
211226.160.210.0/24226.160.210.1 to 226.160.210.254226.160.210.255254
212226.160.211.0/24226.160.211.1 to 226.160.211.254226.160.211.255254
213226.160.212.0/24226.160.212.1 to 226.160.212.254226.160.212.255254
214226.160.213.0/24226.160.213.1 to 226.160.213.254226.160.213.255254
215226.160.214.0/24226.160.214.1 to 226.160.214.254226.160.214.255254
216226.160.215.0/24226.160.215.1 to 226.160.215.254226.160.215.255254
217226.160.216.0/24226.160.216.1 to 226.160.216.254226.160.216.255254
218226.160.217.0/24226.160.217.1 to 226.160.217.254226.160.217.255254
219226.160.218.0/24226.160.218.1 to 226.160.218.254226.160.218.255254
220226.160.219.0/24226.160.219.1 to 226.160.219.254226.160.219.255254
221226.160.220.0/24226.160.220.1 to 226.160.220.254226.160.220.255254
222226.160.221.0/24226.160.221.1 to 226.160.221.254226.160.221.255254
223226.160.222.0/24226.160.222.1 to 226.160.222.254226.160.222.255254
224226.160.223.0/24226.160.223.1 to 226.160.223.254226.160.223.255254
225226.160.224.0/24226.160.224.1 to 226.160.224.254226.160.224.255254
226226.160.225.0/24226.160.225.1 to 226.160.225.254226.160.225.255254
227226.160.226.0/24226.160.226.1 to 226.160.226.254226.160.226.255254
228226.160.227.0/24226.160.227.1 to 226.160.227.254226.160.227.255254
229226.160.228.0/24226.160.228.1 to 226.160.228.254226.160.228.255254
230226.160.229.0/24226.160.229.1 to 226.160.229.254226.160.229.255254
231226.160.230.0/24226.160.230.1 to 226.160.230.254226.160.230.255254
232226.160.231.0/24226.160.231.1 to 226.160.231.254226.160.231.255254
233226.160.232.0/24226.160.232.1 to 226.160.232.254226.160.232.255254
234226.160.233.0/24226.160.233.1 to 226.160.233.254226.160.233.255254
235226.160.234.0/24226.160.234.1 to 226.160.234.254226.160.234.255254
236226.160.235.0/24226.160.235.1 to 226.160.235.254226.160.235.255254
237226.160.236.0/24226.160.236.1 to 226.160.236.254226.160.236.255254
238226.160.237.0/24226.160.237.1 to 226.160.237.254226.160.237.255254
239226.160.238.0/24226.160.238.1 to 226.160.238.254226.160.238.255254
240226.160.239.0/24226.160.239.1 to 226.160.239.254226.160.239.255254
241226.160.240.0/24226.160.240.1 to 226.160.240.254226.160.240.255254
242226.160.241.0/24226.160.241.1 to 226.160.241.254226.160.241.255254
243226.160.242.0/24226.160.242.1 to 226.160.242.254226.160.242.255254
244226.160.243.0/24226.160.243.1 to 226.160.243.254226.160.243.255254
245226.160.244.0/24226.160.244.1 to 226.160.244.254226.160.244.255254
246226.160.245.0/24226.160.245.1 to 226.160.245.254226.160.245.255254
247226.160.246.0/24226.160.246.1 to 226.160.246.254226.160.246.255254
248226.160.247.0/24226.160.247.1 to 226.160.247.254226.160.247.255254
249226.160.248.0/24226.160.248.1 to 226.160.248.254226.160.248.255254
250226.160.249.0/24226.160.249.1 to 226.160.249.254226.160.249.255254
251226.160.250.0/24226.160.250.1 to 226.160.250.254226.160.250.255254
252226.160.251.0/24226.160.251.1 to 226.160.251.254226.160.251.255254
253226.160.252.0/24226.160.252.1 to 226.160.252.254226.160.252.255254
254226.160.253.0/24226.160.253.1 to 226.160.253.254226.160.253.255254
255226.160.254.0/24226.160.254.1 to 226.160.254.254226.160.254.255254
256226.160.255.0/24226.160.255.1 to 226.160.255.254226.160.255.255254

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.