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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.

Network226.168.0.0/13
Usable hosts524,286
Subnet mask255.248.0.0
Addresses524,288
Network address
226.168.0.0
Broadcast address
226.175.255.255
First usable
226.168.0.1
Last usable
226.175.255.254
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 E2A80000 · Integer 3802660864 to 3803185151
Reverse DNS zones
168.226.in-addr.arpa
169.226.in-addr.arpa
170.226.in-addr.arpa
171.226.in-addr.arpa
172.226.in-addr.arpa
173.226.in-addr.arpa
174.226.in-addr.arpa
175.226.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
Address11100010.10101000.00000000.00000000226.168.0.0
Subnet mask11111111.11111000.00000000.00000000255.248.0.0
Network11100010.10101000.00000000.00000000226.168.0.0
Broadcast11100010.10101111.11111111.11111111226.175.255.255
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)

226.168.0.0/13 makes 1,024 subnets of /23; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
1226.168.0.0/23226.168.0.1 to 226.168.1.254226.168.1.255510
2226.168.2.0/23226.168.2.1 to 226.168.3.254226.168.3.255510
3226.168.4.0/23226.168.4.1 to 226.168.5.254226.168.5.255510
4226.168.6.0/23226.168.6.1 to 226.168.7.254226.168.7.255510
5226.168.8.0/23226.168.8.1 to 226.168.9.254226.168.9.255510
6226.168.10.0/23226.168.10.1 to 226.168.11.254226.168.11.255510
7226.168.12.0/23226.168.12.1 to 226.168.13.254226.168.13.255510
8226.168.14.0/23226.168.14.1 to 226.168.15.254226.168.15.255510
9226.168.16.0/23226.168.16.1 to 226.168.17.254226.168.17.255510
10226.168.18.0/23226.168.18.1 to 226.168.19.254226.168.19.255510
11226.168.20.0/23226.168.20.1 to 226.168.21.254226.168.21.255510
12226.168.22.0/23226.168.22.1 to 226.168.23.254226.168.23.255510
13226.168.24.0/23226.168.24.1 to 226.168.25.254226.168.25.255510
14226.168.26.0/23226.168.26.1 to 226.168.27.254226.168.27.255510
15226.168.28.0/23226.168.28.1 to 226.168.29.254226.168.29.255510
16226.168.30.0/23226.168.30.1 to 226.168.31.254226.168.31.255510
17226.168.32.0/23226.168.32.1 to 226.168.33.254226.168.33.255510
18226.168.34.0/23226.168.34.1 to 226.168.35.254226.168.35.255510
19226.168.36.0/23226.168.36.1 to 226.168.37.254226.168.37.255510
20226.168.38.0/23226.168.38.1 to 226.168.39.254226.168.39.255510
21226.168.40.0/23226.168.40.1 to 226.168.41.254226.168.41.255510
22226.168.42.0/23226.168.42.1 to 226.168.43.254226.168.43.255510
23226.168.44.0/23226.168.44.1 to 226.168.45.254226.168.45.255510
24226.168.46.0/23226.168.46.1 to 226.168.47.254226.168.47.255510
25226.168.48.0/23226.168.48.1 to 226.168.49.254226.168.49.255510
26226.168.50.0/23226.168.50.1 to 226.168.51.254226.168.51.255510
27226.168.52.0/23226.168.52.1 to 226.168.53.254226.168.53.255510
28226.168.54.0/23226.168.54.1 to 226.168.55.254226.168.55.255510
29226.168.56.0/23226.168.56.1 to 226.168.57.254226.168.57.255510
30226.168.58.0/23226.168.58.1 to 226.168.59.254226.168.59.255510
31226.168.60.0/23226.168.60.1 to 226.168.61.254226.168.61.255510
32226.168.62.0/23226.168.62.1 to 226.168.63.254226.168.63.255510
33226.168.64.0/23226.168.64.1 to 226.168.65.254226.168.65.255510
34226.168.66.0/23226.168.66.1 to 226.168.67.254226.168.67.255510
35226.168.68.0/23226.168.68.1 to 226.168.69.254226.168.69.255510
36226.168.70.0/23226.168.70.1 to 226.168.71.254226.168.71.255510
37226.168.72.0/23226.168.72.1 to 226.168.73.254226.168.73.255510
38226.168.74.0/23226.168.74.1 to 226.168.75.254226.168.75.255510
39226.168.76.0/23226.168.76.1 to 226.168.77.254226.168.77.255510
40226.168.78.0/23226.168.78.1 to 226.168.79.254226.168.79.255510
41226.168.80.0/23226.168.80.1 to 226.168.81.254226.168.81.255510
42226.168.82.0/23226.168.82.1 to 226.168.83.254226.168.83.255510
43226.168.84.0/23226.168.84.1 to 226.168.85.254226.168.85.255510
44226.168.86.0/23226.168.86.1 to 226.168.87.254226.168.87.255510
45226.168.88.0/23226.168.88.1 to 226.168.89.254226.168.89.255510
46226.168.90.0/23226.168.90.1 to 226.168.91.254226.168.91.255510
47226.168.92.0/23226.168.92.1 to 226.168.93.254226.168.93.255510
48226.168.94.0/23226.168.94.1 to 226.168.95.254226.168.95.255510
49226.168.96.0/23226.168.96.1 to 226.168.97.254226.168.97.255510
50226.168.98.0/23226.168.98.1 to 226.168.99.254226.168.99.255510
51226.168.100.0/23226.168.100.1 to 226.168.101.254226.168.101.255510
52226.168.102.0/23226.168.102.1 to 226.168.103.254226.168.103.255510
53226.168.104.0/23226.168.104.1 to 226.168.105.254226.168.105.255510
54226.168.106.0/23226.168.106.1 to 226.168.107.254226.168.107.255510
55226.168.108.0/23226.168.108.1 to 226.168.109.254226.168.109.255510
56226.168.110.0/23226.168.110.1 to 226.168.111.254226.168.111.255510
57226.168.112.0/23226.168.112.1 to 226.168.113.254226.168.113.255510
58226.168.114.0/23226.168.114.1 to 226.168.115.254226.168.115.255510
59226.168.116.0/23226.168.116.1 to 226.168.117.254226.168.117.255510
60226.168.118.0/23226.168.118.1 to 226.168.119.254226.168.119.255510
61226.168.120.0/23226.168.120.1 to 226.168.121.254226.168.121.255510
62226.168.122.0/23226.168.122.1 to 226.168.123.254226.168.123.255510
63226.168.124.0/23226.168.124.1 to 226.168.125.254226.168.125.255510
64226.168.126.0/23226.168.126.1 to 226.168.127.254226.168.127.255510
65226.168.128.0/23226.168.128.1 to 226.168.129.254226.168.129.255510
66226.168.130.0/23226.168.130.1 to 226.168.131.254226.168.131.255510
67226.168.132.0/23226.168.132.1 to 226.168.133.254226.168.133.255510
68226.168.134.0/23226.168.134.1 to 226.168.135.254226.168.135.255510
69226.168.136.0/23226.168.136.1 to 226.168.137.254226.168.137.255510
70226.168.138.0/23226.168.138.1 to 226.168.139.254226.168.139.255510
71226.168.140.0/23226.168.140.1 to 226.168.141.254226.168.141.255510
72226.168.142.0/23226.168.142.1 to 226.168.143.254226.168.143.255510
73226.168.144.0/23226.168.144.1 to 226.168.145.254226.168.145.255510
74226.168.146.0/23226.168.146.1 to 226.168.147.254226.168.147.255510
75226.168.148.0/23226.168.148.1 to 226.168.149.254226.168.149.255510
76226.168.150.0/23226.168.150.1 to 226.168.151.254226.168.151.255510
77226.168.152.0/23226.168.152.1 to 226.168.153.254226.168.153.255510
78226.168.154.0/23226.168.154.1 to 226.168.155.254226.168.155.255510
79226.168.156.0/23226.168.156.1 to 226.168.157.254226.168.157.255510
80226.168.158.0/23226.168.158.1 to 226.168.159.254226.168.159.255510
81226.168.160.0/23226.168.160.1 to 226.168.161.254226.168.161.255510
82226.168.162.0/23226.168.162.1 to 226.168.163.254226.168.163.255510
83226.168.164.0/23226.168.164.1 to 226.168.165.254226.168.165.255510
84226.168.166.0/23226.168.166.1 to 226.168.167.254226.168.167.255510
85226.168.168.0/23226.168.168.1 to 226.168.169.254226.168.169.255510
86226.168.170.0/23226.168.170.1 to 226.168.171.254226.168.171.255510
87226.168.172.0/23226.168.172.1 to 226.168.173.254226.168.173.255510
88226.168.174.0/23226.168.174.1 to 226.168.175.254226.168.175.255510
89226.168.176.0/23226.168.176.1 to 226.168.177.254226.168.177.255510
90226.168.178.0/23226.168.178.1 to 226.168.179.254226.168.179.255510
91226.168.180.0/23226.168.180.1 to 226.168.181.254226.168.181.255510
92226.168.182.0/23226.168.182.1 to 226.168.183.254226.168.183.255510
93226.168.184.0/23226.168.184.1 to 226.168.185.254226.168.185.255510
94226.168.186.0/23226.168.186.1 to 226.168.187.254226.168.187.255510
95226.168.188.0/23226.168.188.1 to 226.168.189.254226.168.189.255510
96226.168.190.0/23226.168.190.1 to 226.168.191.254226.168.191.255510
97226.168.192.0/23226.168.192.1 to 226.168.193.254226.168.193.255510
98226.168.194.0/23226.168.194.1 to 226.168.195.254226.168.195.255510
99226.168.196.0/23226.168.196.1 to 226.168.197.254226.168.197.255510
100226.168.198.0/23226.168.198.1 to 226.168.199.254226.168.199.255510
101226.168.200.0/23226.168.200.1 to 226.168.201.254226.168.201.255510
102226.168.202.0/23226.168.202.1 to 226.168.203.254226.168.203.255510
103226.168.204.0/23226.168.204.1 to 226.168.205.254226.168.205.255510
104226.168.206.0/23226.168.206.1 to 226.168.207.254226.168.207.255510
105226.168.208.0/23226.168.208.1 to 226.168.209.254226.168.209.255510
106226.168.210.0/23226.168.210.1 to 226.168.211.254226.168.211.255510
107226.168.212.0/23226.168.212.1 to 226.168.213.254226.168.213.255510
108226.168.214.0/23226.168.214.1 to 226.168.215.254226.168.215.255510
109226.168.216.0/23226.168.216.1 to 226.168.217.254226.168.217.255510
110226.168.218.0/23226.168.218.1 to 226.168.219.254226.168.219.255510
111226.168.220.0/23226.168.220.1 to 226.168.221.254226.168.221.255510
112226.168.222.0/23226.168.222.1 to 226.168.223.254226.168.223.255510
113226.168.224.0/23226.168.224.1 to 226.168.225.254226.168.225.255510
114226.168.226.0/23226.168.226.1 to 226.168.227.254226.168.227.255510
115226.168.228.0/23226.168.228.1 to 226.168.229.254226.168.229.255510
116226.168.230.0/23226.168.230.1 to 226.168.231.254226.168.231.255510
117226.168.232.0/23226.168.232.1 to 226.168.233.254226.168.233.255510
118226.168.234.0/23226.168.234.1 to 226.168.235.254226.168.235.255510
119226.168.236.0/23226.168.236.1 to 226.168.237.254226.168.237.255510
120226.168.238.0/23226.168.238.1 to 226.168.239.254226.168.239.255510
121226.168.240.0/23226.168.240.1 to 226.168.241.254226.168.241.255510
122226.168.242.0/23226.168.242.1 to 226.168.243.254226.168.243.255510
123226.168.244.0/23226.168.244.1 to 226.168.245.254226.168.245.255510
124226.168.246.0/23226.168.246.1 to 226.168.247.254226.168.247.255510
125226.168.248.0/23226.168.248.1 to 226.168.249.254226.168.249.255510
126226.168.250.0/23226.168.250.1 to 226.168.251.254226.168.251.255510
127226.168.252.0/23226.168.252.1 to 226.168.253.254226.168.253.255510
128226.168.254.0/23226.168.254.1 to 226.168.255.254226.168.255.255510
129226.169.0.0/23226.169.0.1 to 226.169.1.254226.169.1.255510
130226.169.2.0/23226.169.2.1 to 226.169.3.254226.169.3.255510
131226.169.4.0/23226.169.4.1 to 226.169.5.254226.169.5.255510
132226.169.6.0/23226.169.6.1 to 226.169.7.254226.169.7.255510
133226.169.8.0/23226.169.8.1 to 226.169.9.254226.169.9.255510
134226.169.10.0/23226.169.10.1 to 226.169.11.254226.169.11.255510
135226.169.12.0/23226.169.12.1 to 226.169.13.254226.169.13.255510
136226.169.14.0/23226.169.14.1 to 226.169.15.254226.169.15.255510
137226.169.16.0/23226.169.16.1 to 226.169.17.254226.169.17.255510
138226.169.18.0/23226.169.18.1 to 226.169.19.254226.169.19.255510
139226.169.20.0/23226.169.20.1 to 226.169.21.254226.169.21.255510
140226.169.22.0/23226.169.22.1 to 226.169.23.254226.169.23.255510
141226.169.24.0/23226.169.24.1 to 226.169.25.254226.169.25.255510
142226.169.26.0/23226.169.26.1 to 226.169.27.254226.169.27.255510
143226.169.28.0/23226.169.28.1 to 226.169.29.254226.169.29.255510
144226.169.30.0/23226.169.30.1 to 226.169.31.254226.169.31.255510
145226.169.32.0/23226.169.32.1 to 226.169.33.254226.169.33.255510
146226.169.34.0/23226.169.34.1 to 226.169.35.254226.169.35.255510
147226.169.36.0/23226.169.36.1 to 226.169.37.254226.169.37.255510
148226.169.38.0/23226.169.38.1 to 226.169.39.254226.169.39.255510
149226.169.40.0/23226.169.40.1 to 226.169.41.254226.169.41.255510
150226.169.42.0/23226.169.42.1 to 226.169.43.254226.169.43.255510
151226.169.44.0/23226.169.44.1 to 226.169.45.254226.169.45.255510
152226.169.46.0/23226.169.46.1 to 226.169.47.254226.169.47.255510
153226.169.48.0/23226.169.48.1 to 226.169.49.254226.169.49.255510
154226.169.50.0/23226.169.50.1 to 226.169.51.254226.169.51.255510
155226.169.52.0/23226.169.52.1 to 226.169.53.254226.169.53.255510
156226.169.54.0/23226.169.54.1 to 226.169.55.254226.169.55.255510
157226.169.56.0/23226.169.56.1 to 226.169.57.254226.169.57.255510
158226.169.58.0/23226.169.58.1 to 226.169.59.254226.169.59.255510
159226.169.60.0/23226.169.60.1 to 226.169.61.254226.169.61.255510
160226.169.62.0/23226.169.62.1 to 226.169.63.254226.169.63.255510
161226.169.64.0/23226.169.64.1 to 226.169.65.254226.169.65.255510
162226.169.66.0/23226.169.66.1 to 226.169.67.254226.169.67.255510
163226.169.68.0/23226.169.68.1 to 226.169.69.254226.169.69.255510
164226.169.70.0/23226.169.70.1 to 226.169.71.254226.169.71.255510
165226.169.72.0/23226.169.72.1 to 226.169.73.254226.169.73.255510
166226.169.74.0/23226.169.74.1 to 226.169.75.254226.169.75.255510
167226.169.76.0/23226.169.76.1 to 226.169.77.254226.169.77.255510
168226.169.78.0/23226.169.78.1 to 226.169.79.254226.169.79.255510
169226.169.80.0/23226.169.80.1 to 226.169.81.254226.169.81.255510
170226.169.82.0/23226.169.82.1 to 226.169.83.254226.169.83.255510
171226.169.84.0/23226.169.84.1 to 226.169.85.254226.169.85.255510
172226.169.86.0/23226.169.86.1 to 226.169.87.254226.169.87.255510
173226.169.88.0/23226.169.88.1 to 226.169.89.254226.169.89.255510
174226.169.90.0/23226.169.90.1 to 226.169.91.254226.169.91.255510
175226.169.92.0/23226.169.92.1 to 226.169.93.254226.169.93.255510
176226.169.94.0/23226.169.94.1 to 226.169.95.254226.169.95.255510
177226.169.96.0/23226.169.96.1 to 226.169.97.254226.169.97.255510
178226.169.98.0/23226.169.98.1 to 226.169.99.254226.169.99.255510
179226.169.100.0/23226.169.100.1 to 226.169.101.254226.169.101.255510
180226.169.102.0/23226.169.102.1 to 226.169.103.254226.169.103.255510
181226.169.104.0/23226.169.104.1 to 226.169.105.254226.169.105.255510
182226.169.106.0/23226.169.106.1 to 226.169.107.254226.169.107.255510
183226.169.108.0/23226.169.108.1 to 226.169.109.254226.169.109.255510
184226.169.110.0/23226.169.110.1 to 226.169.111.254226.169.111.255510
185226.169.112.0/23226.169.112.1 to 226.169.113.254226.169.113.255510
186226.169.114.0/23226.169.114.1 to 226.169.115.254226.169.115.255510
187226.169.116.0/23226.169.116.1 to 226.169.117.254226.169.117.255510
188226.169.118.0/23226.169.118.1 to 226.169.119.254226.169.119.255510
189226.169.120.0/23226.169.120.1 to 226.169.121.254226.169.121.255510
190226.169.122.0/23226.169.122.1 to 226.169.123.254226.169.123.255510
191226.169.124.0/23226.169.124.1 to 226.169.125.254226.169.125.255510
192226.169.126.0/23226.169.126.1 to 226.169.127.254226.169.127.255510
193226.169.128.0/23226.169.128.1 to 226.169.129.254226.169.129.255510
194226.169.130.0/23226.169.130.1 to 226.169.131.254226.169.131.255510
195226.169.132.0/23226.169.132.1 to 226.169.133.254226.169.133.255510
196226.169.134.0/23226.169.134.1 to 226.169.135.254226.169.135.255510
197226.169.136.0/23226.169.136.1 to 226.169.137.254226.169.137.255510
198226.169.138.0/23226.169.138.1 to 226.169.139.254226.169.139.255510
199226.169.140.0/23226.169.140.1 to 226.169.141.254226.169.141.255510
200226.169.142.0/23226.169.142.1 to 226.169.143.254226.169.143.255510
201226.169.144.0/23226.169.144.1 to 226.169.145.254226.169.145.255510
202226.169.146.0/23226.169.146.1 to 226.169.147.254226.169.147.255510
203226.169.148.0/23226.169.148.1 to 226.169.149.254226.169.149.255510
204226.169.150.0/23226.169.150.1 to 226.169.151.254226.169.151.255510
205226.169.152.0/23226.169.152.1 to 226.169.153.254226.169.153.255510
206226.169.154.0/23226.169.154.1 to 226.169.155.254226.169.155.255510
207226.169.156.0/23226.169.156.1 to 226.169.157.254226.169.157.255510
208226.169.158.0/23226.169.158.1 to 226.169.159.254226.169.159.255510
209226.169.160.0/23226.169.160.1 to 226.169.161.254226.169.161.255510
210226.169.162.0/23226.169.162.1 to 226.169.163.254226.169.163.255510
211226.169.164.0/23226.169.164.1 to 226.169.165.254226.169.165.255510
212226.169.166.0/23226.169.166.1 to 226.169.167.254226.169.167.255510
213226.169.168.0/23226.169.168.1 to 226.169.169.254226.169.169.255510
214226.169.170.0/23226.169.170.1 to 226.169.171.254226.169.171.255510
215226.169.172.0/23226.169.172.1 to 226.169.173.254226.169.173.255510
216226.169.174.0/23226.169.174.1 to 226.169.175.254226.169.175.255510
217226.169.176.0/23226.169.176.1 to 226.169.177.254226.169.177.255510
218226.169.178.0/23226.169.178.1 to 226.169.179.254226.169.179.255510
219226.169.180.0/23226.169.180.1 to 226.169.181.254226.169.181.255510
220226.169.182.0/23226.169.182.1 to 226.169.183.254226.169.183.255510
221226.169.184.0/23226.169.184.1 to 226.169.185.254226.169.185.255510
222226.169.186.0/23226.169.186.1 to 226.169.187.254226.169.187.255510
223226.169.188.0/23226.169.188.1 to 226.169.189.254226.169.189.255510
224226.169.190.0/23226.169.190.1 to 226.169.191.254226.169.191.255510
225226.169.192.0/23226.169.192.1 to 226.169.193.254226.169.193.255510
226226.169.194.0/23226.169.194.1 to 226.169.195.254226.169.195.255510
227226.169.196.0/23226.169.196.1 to 226.169.197.254226.169.197.255510
228226.169.198.0/23226.169.198.1 to 226.169.199.254226.169.199.255510
229226.169.200.0/23226.169.200.1 to 226.169.201.254226.169.201.255510
230226.169.202.0/23226.169.202.1 to 226.169.203.254226.169.203.255510
231226.169.204.0/23226.169.204.1 to 226.169.205.254226.169.205.255510
232226.169.206.0/23226.169.206.1 to 226.169.207.254226.169.207.255510
233226.169.208.0/23226.169.208.1 to 226.169.209.254226.169.209.255510
234226.169.210.0/23226.169.210.1 to 226.169.211.254226.169.211.255510
235226.169.212.0/23226.169.212.1 to 226.169.213.254226.169.213.255510
236226.169.214.0/23226.169.214.1 to 226.169.215.254226.169.215.255510
237226.169.216.0/23226.169.216.1 to 226.169.217.254226.169.217.255510
238226.169.218.0/23226.169.218.1 to 226.169.219.254226.169.219.255510
239226.169.220.0/23226.169.220.1 to 226.169.221.254226.169.221.255510
240226.169.222.0/23226.169.222.1 to 226.169.223.254226.169.223.255510
241226.169.224.0/23226.169.224.1 to 226.169.225.254226.169.225.255510
242226.169.226.0/23226.169.226.1 to 226.169.227.254226.169.227.255510
243226.169.228.0/23226.169.228.1 to 226.169.229.254226.169.229.255510
244226.169.230.0/23226.169.230.1 to 226.169.231.254226.169.231.255510
245226.169.232.0/23226.169.232.1 to 226.169.233.254226.169.233.255510
246226.169.234.0/23226.169.234.1 to 226.169.235.254226.169.235.255510
247226.169.236.0/23226.169.236.1 to 226.169.237.254226.169.237.255510
248226.169.238.0/23226.169.238.1 to 226.169.239.254226.169.239.255510
249226.169.240.0/23226.169.240.1 to 226.169.241.254226.169.241.255510
250226.169.242.0/23226.169.242.1 to 226.169.243.254226.169.243.255510
251226.169.244.0/23226.169.244.1 to 226.169.245.254226.169.245.255510
252226.169.246.0/23226.169.246.1 to 226.169.247.254226.169.247.255510
253226.169.248.0/23226.169.248.1 to 226.169.249.254226.169.249.255510
254226.169.250.0/23226.169.250.1 to 226.169.251.254226.169.251.255510
255226.169.252.0/23226.169.252.1 to 226.169.253.254226.169.253.255510
256226.169.254.0/23226.169.254.1 to 226.169.255.254226.169.255.255510

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.