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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.

Network226.128.0.0/10
Usable hosts4,194,302
Subnet mask255.192.0.0
Addresses4,194,304
Network address
226.128.0.0
Broadcast address
226.191.255.255
First usable
226.128.0.1
Last usable
226.191.255.254
Usable hosts
4,194,302 (4,194,304 less the network and broadcast addresses)
Subnet mask
255.192.0.0
Wildcard mask
0.63.255.255 (Cisco ACLs, OSPF)
Prefix length
/10
Type
Multicast 224.0.0.0/4
One-to-many traffic, such as IPTV and routing protocols
Old class
D (multicast)
As numbers
Hex E2800000 · Integer 3800039424 to 3804233727
Reverse DNS zones
128.226.in-addr.arpa
129.226.in-addr.arpa
130.226.in-addr.arpa
131.226.in-addr.arpa
132.226.in-addr.arpa
133.226.in-addr.arpa
134.226.in-addr.arpa
135.226.in-addr.arpa
136.226.in-addr.arpa
137.226.in-addr.arpa
138.226.in-addr.arpa
139.226.in-addr.arpa
140.226.in-addr.arpa
141.226.in-addr.arpa
142.226.in-addr.arpa
143.226.in-addr.arpa
and 48 more
/10 is not on a 8-bit boundary, so it takes 64 /16 zones.
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address11100010.10000000.00000000.00000000226.128.0.0
Subnet mask11111111.11000000.00000000.00000000255.192.0.0
Network11100010.10000000.00000000.00000000226.128.0.0
Broadcast11100010.10111111.11111111.11111111226.191.255.255
Split into smaller subnets/19
/11 (2)/12 (4)/13 (8)/14 (16)/15 (32)/16 (64)/17 (128)/18 (256)/19 (512)/20 (1,024)/21 (2,048)/22 (4,096)

226.128.0.0/10 makes 512 subnets of /19; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
1226.128.0.0/19226.128.0.1 to 226.128.31.254226.128.31.2558,190
2226.128.32.0/19226.128.32.1 to 226.128.63.254226.128.63.2558,190
3226.128.64.0/19226.128.64.1 to 226.128.95.254226.128.95.2558,190
4226.128.96.0/19226.128.96.1 to 226.128.127.254226.128.127.2558,190
5226.128.128.0/19226.128.128.1 to 226.128.159.254226.128.159.2558,190
6226.128.160.0/19226.128.160.1 to 226.128.191.254226.128.191.2558,190
7226.128.192.0/19226.128.192.1 to 226.128.223.254226.128.223.2558,190
8226.128.224.0/19226.128.224.1 to 226.128.255.254226.128.255.2558,190
9226.129.0.0/19226.129.0.1 to 226.129.31.254226.129.31.2558,190
10226.129.32.0/19226.129.32.1 to 226.129.63.254226.129.63.2558,190
11226.129.64.0/19226.129.64.1 to 226.129.95.254226.129.95.2558,190
12226.129.96.0/19226.129.96.1 to 226.129.127.254226.129.127.2558,190
13226.129.128.0/19226.129.128.1 to 226.129.159.254226.129.159.2558,190
14226.129.160.0/19226.129.160.1 to 226.129.191.254226.129.191.2558,190
15226.129.192.0/19226.129.192.1 to 226.129.223.254226.129.223.2558,190
16226.129.224.0/19226.129.224.1 to 226.129.255.254226.129.255.2558,190
17226.130.0.0/19226.130.0.1 to 226.130.31.254226.130.31.2558,190
18226.130.32.0/19226.130.32.1 to 226.130.63.254226.130.63.2558,190
19226.130.64.0/19226.130.64.1 to 226.130.95.254226.130.95.2558,190
20226.130.96.0/19226.130.96.1 to 226.130.127.254226.130.127.2558,190
21226.130.128.0/19226.130.128.1 to 226.130.159.254226.130.159.2558,190
22226.130.160.0/19226.130.160.1 to 226.130.191.254226.130.191.2558,190
23226.130.192.0/19226.130.192.1 to 226.130.223.254226.130.223.2558,190
24226.130.224.0/19226.130.224.1 to 226.130.255.254226.130.255.2558,190
25226.131.0.0/19226.131.0.1 to 226.131.31.254226.131.31.2558,190
26226.131.32.0/19226.131.32.1 to 226.131.63.254226.131.63.2558,190
27226.131.64.0/19226.131.64.1 to 226.131.95.254226.131.95.2558,190
28226.131.96.0/19226.131.96.1 to 226.131.127.254226.131.127.2558,190
29226.131.128.0/19226.131.128.1 to 226.131.159.254226.131.159.2558,190
30226.131.160.0/19226.131.160.1 to 226.131.191.254226.131.191.2558,190
31226.131.192.0/19226.131.192.1 to 226.131.223.254226.131.223.2558,190
32226.131.224.0/19226.131.224.1 to 226.131.255.254226.131.255.2558,190
33226.132.0.0/19226.132.0.1 to 226.132.31.254226.132.31.2558,190
34226.132.32.0/19226.132.32.1 to 226.132.63.254226.132.63.2558,190
35226.132.64.0/19226.132.64.1 to 226.132.95.254226.132.95.2558,190
36226.132.96.0/19226.132.96.1 to 226.132.127.254226.132.127.2558,190
37226.132.128.0/19226.132.128.1 to 226.132.159.254226.132.159.2558,190
38226.132.160.0/19226.132.160.1 to 226.132.191.254226.132.191.2558,190
39226.132.192.0/19226.132.192.1 to 226.132.223.254226.132.223.2558,190
40226.132.224.0/19226.132.224.1 to 226.132.255.254226.132.255.2558,190
41226.133.0.0/19226.133.0.1 to 226.133.31.254226.133.31.2558,190
42226.133.32.0/19226.133.32.1 to 226.133.63.254226.133.63.2558,190
43226.133.64.0/19226.133.64.1 to 226.133.95.254226.133.95.2558,190
44226.133.96.0/19226.133.96.1 to 226.133.127.254226.133.127.2558,190
45226.133.128.0/19226.133.128.1 to 226.133.159.254226.133.159.2558,190
46226.133.160.0/19226.133.160.1 to 226.133.191.254226.133.191.2558,190
47226.133.192.0/19226.133.192.1 to 226.133.223.254226.133.223.2558,190
48226.133.224.0/19226.133.224.1 to 226.133.255.254226.133.255.2558,190
49226.134.0.0/19226.134.0.1 to 226.134.31.254226.134.31.2558,190
50226.134.32.0/19226.134.32.1 to 226.134.63.254226.134.63.2558,190
51226.134.64.0/19226.134.64.1 to 226.134.95.254226.134.95.2558,190
52226.134.96.0/19226.134.96.1 to 226.134.127.254226.134.127.2558,190
53226.134.128.0/19226.134.128.1 to 226.134.159.254226.134.159.2558,190
54226.134.160.0/19226.134.160.1 to 226.134.191.254226.134.191.2558,190
55226.134.192.0/19226.134.192.1 to 226.134.223.254226.134.223.2558,190
56226.134.224.0/19226.134.224.1 to 226.134.255.254226.134.255.2558,190
57226.135.0.0/19226.135.0.1 to 226.135.31.254226.135.31.2558,190
58226.135.32.0/19226.135.32.1 to 226.135.63.254226.135.63.2558,190
59226.135.64.0/19226.135.64.1 to 226.135.95.254226.135.95.2558,190
60226.135.96.0/19226.135.96.1 to 226.135.127.254226.135.127.2558,190
61226.135.128.0/19226.135.128.1 to 226.135.159.254226.135.159.2558,190
62226.135.160.0/19226.135.160.1 to 226.135.191.254226.135.191.2558,190
63226.135.192.0/19226.135.192.1 to 226.135.223.254226.135.223.2558,190
64226.135.224.0/19226.135.224.1 to 226.135.255.254226.135.255.2558,190
65226.136.0.0/19226.136.0.1 to 226.136.31.254226.136.31.2558,190
66226.136.32.0/19226.136.32.1 to 226.136.63.254226.136.63.2558,190
67226.136.64.0/19226.136.64.1 to 226.136.95.254226.136.95.2558,190
68226.136.96.0/19226.136.96.1 to 226.136.127.254226.136.127.2558,190
69226.136.128.0/19226.136.128.1 to 226.136.159.254226.136.159.2558,190
70226.136.160.0/19226.136.160.1 to 226.136.191.254226.136.191.2558,190
71226.136.192.0/19226.136.192.1 to 226.136.223.254226.136.223.2558,190
72226.136.224.0/19226.136.224.1 to 226.136.255.254226.136.255.2558,190
73226.137.0.0/19226.137.0.1 to 226.137.31.254226.137.31.2558,190
74226.137.32.0/19226.137.32.1 to 226.137.63.254226.137.63.2558,190
75226.137.64.0/19226.137.64.1 to 226.137.95.254226.137.95.2558,190
76226.137.96.0/19226.137.96.1 to 226.137.127.254226.137.127.2558,190
77226.137.128.0/19226.137.128.1 to 226.137.159.254226.137.159.2558,190
78226.137.160.0/19226.137.160.1 to 226.137.191.254226.137.191.2558,190
79226.137.192.0/19226.137.192.1 to 226.137.223.254226.137.223.2558,190
80226.137.224.0/19226.137.224.1 to 226.137.255.254226.137.255.2558,190
81226.138.0.0/19226.138.0.1 to 226.138.31.254226.138.31.2558,190
82226.138.32.0/19226.138.32.1 to 226.138.63.254226.138.63.2558,190
83226.138.64.0/19226.138.64.1 to 226.138.95.254226.138.95.2558,190
84226.138.96.0/19226.138.96.1 to 226.138.127.254226.138.127.2558,190
85226.138.128.0/19226.138.128.1 to 226.138.159.254226.138.159.2558,190
86226.138.160.0/19226.138.160.1 to 226.138.191.254226.138.191.2558,190
87226.138.192.0/19226.138.192.1 to 226.138.223.254226.138.223.2558,190
88226.138.224.0/19226.138.224.1 to 226.138.255.254226.138.255.2558,190
89226.139.0.0/19226.139.0.1 to 226.139.31.254226.139.31.2558,190
90226.139.32.0/19226.139.32.1 to 226.139.63.254226.139.63.2558,190
91226.139.64.0/19226.139.64.1 to 226.139.95.254226.139.95.2558,190
92226.139.96.0/19226.139.96.1 to 226.139.127.254226.139.127.2558,190
93226.139.128.0/19226.139.128.1 to 226.139.159.254226.139.159.2558,190
94226.139.160.0/19226.139.160.1 to 226.139.191.254226.139.191.2558,190
95226.139.192.0/19226.139.192.1 to 226.139.223.254226.139.223.2558,190
96226.139.224.0/19226.139.224.1 to 226.139.255.254226.139.255.2558,190
97226.140.0.0/19226.140.0.1 to 226.140.31.254226.140.31.2558,190
98226.140.32.0/19226.140.32.1 to 226.140.63.254226.140.63.2558,190
99226.140.64.0/19226.140.64.1 to 226.140.95.254226.140.95.2558,190
100226.140.96.0/19226.140.96.1 to 226.140.127.254226.140.127.2558,190
101226.140.128.0/19226.140.128.1 to 226.140.159.254226.140.159.2558,190
102226.140.160.0/19226.140.160.1 to 226.140.191.254226.140.191.2558,190
103226.140.192.0/19226.140.192.1 to 226.140.223.254226.140.223.2558,190
104226.140.224.0/19226.140.224.1 to 226.140.255.254226.140.255.2558,190
105226.141.0.0/19226.141.0.1 to 226.141.31.254226.141.31.2558,190
106226.141.32.0/19226.141.32.1 to 226.141.63.254226.141.63.2558,190
107226.141.64.0/19226.141.64.1 to 226.141.95.254226.141.95.2558,190
108226.141.96.0/19226.141.96.1 to 226.141.127.254226.141.127.2558,190
109226.141.128.0/19226.141.128.1 to 226.141.159.254226.141.159.2558,190
110226.141.160.0/19226.141.160.1 to 226.141.191.254226.141.191.2558,190
111226.141.192.0/19226.141.192.1 to 226.141.223.254226.141.223.2558,190
112226.141.224.0/19226.141.224.1 to 226.141.255.254226.141.255.2558,190
113226.142.0.0/19226.142.0.1 to 226.142.31.254226.142.31.2558,190
114226.142.32.0/19226.142.32.1 to 226.142.63.254226.142.63.2558,190
115226.142.64.0/19226.142.64.1 to 226.142.95.254226.142.95.2558,190
116226.142.96.0/19226.142.96.1 to 226.142.127.254226.142.127.2558,190
117226.142.128.0/19226.142.128.1 to 226.142.159.254226.142.159.2558,190
118226.142.160.0/19226.142.160.1 to 226.142.191.254226.142.191.2558,190
119226.142.192.0/19226.142.192.1 to 226.142.223.254226.142.223.2558,190
120226.142.224.0/19226.142.224.1 to 226.142.255.254226.142.255.2558,190
121226.143.0.0/19226.143.0.1 to 226.143.31.254226.143.31.2558,190
122226.143.32.0/19226.143.32.1 to 226.143.63.254226.143.63.2558,190
123226.143.64.0/19226.143.64.1 to 226.143.95.254226.143.95.2558,190
124226.143.96.0/19226.143.96.1 to 226.143.127.254226.143.127.2558,190
125226.143.128.0/19226.143.128.1 to 226.143.159.254226.143.159.2558,190
126226.143.160.0/19226.143.160.1 to 226.143.191.254226.143.191.2558,190
127226.143.192.0/19226.143.192.1 to 226.143.223.254226.143.223.2558,190
128226.143.224.0/19226.143.224.1 to 226.143.255.254226.143.255.2558,190
129226.144.0.0/19226.144.0.1 to 226.144.31.254226.144.31.2558,190
130226.144.32.0/19226.144.32.1 to 226.144.63.254226.144.63.2558,190
131226.144.64.0/19226.144.64.1 to 226.144.95.254226.144.95.2558,190
132226.144.96.0/19226.144.96.1 to 226.144.127.254226.144.127.2558,190
133226.144.128.0/19226.144.128.1 to 226.144.159.254226.144.159.2558,190
134226.144.160.0/19226.144.160.1 to 226.144.191.254226.144.191.2558,190
135226.144.192.0/19226.144.192.1 to 226.144.223.254226.144.223.2558,190
136226.144.224.0/19226.144.224.1 to 226.144.255.254226.144.255.2558,190
137226.145.0.0/19226.145.0.1 to 226.145.31.254226.145.31.2558,190
138226.145.32.0/19226.145.32.1 to 226.145.63.254226.145.63.2558,190
139226.145.64.0/19226.145.64.1 to 226.145.95.254226.145.95.2558,190
140226.145.96.0/19226.145.96.1 to 226.145.127.254226.145.127.2558,190
141226.145.128.0/19226.145.128.1 to 226.145.159.254226.145.159.2558,190
142226.145.160.0/19226.145.160.1 to 226.145.191.254226.145.191.2558,190
143226.145.192.0/19226.145.192.1 to 226.145.223.254226.145.223.2558,190
144226.145.224.0/19226.145.224.1 to 226.145.255.254226.145.255.2558,190
145226.146.0.0/19226.146.0.1 to 226.146.31.254226.146.31.2558,190
146226.146.32.0/19226.146.32.1 to 226.146.63.254226.146.63.2558,190
147226.146.64.0/19226.146.64.1 to 226.146.95.254226.146.95.2558,190
148226.146.96.0/19226.146.96.1 to 226.146.127.254226.146.127.2558,190
149226.146.128.0/19226.146.128.1 to 226.146.159.254226.146.159.2558,190
150226.146.160.0/19226.146.160.1 to 226.146.191.254226.146.191.2558,190
151226.146.192.0/19226.146.192.1 to 226.146.223.254226.146.223.2558,190
152226.146.224.0/19226.146.224.1 to 226.146.255.254226.146.255.2558,190
153226.147.0.0/19226.147.0.1 to 226.147.31.254226.147.31.2558,190
154226.147.32.0/19226.147.32.1 to 226.147.63.254226.147.63.2558,190
155226.147.64.0/19226.147.64.1 to 226.147.95.254226.147.95.2558,190
156226.147.96.0/19226.147.96.1 to 226.147.127.254226.147.127.2558,190
157226.147.128.0/19226.147.128.1 to 226.147.159.254226.147.159.2558,190
158226.147.160.0/19226.147.160.1 to 226.147.191.254226.147.191.2558,190
159226.147.192.0/19226.147.192.1 to 226.147.223.254226.147.223.2558,190
160226.147.224.0/19226.147.224.1 to 226.147.255.254226.147.255.2558,190
161226.148.0.0/19226.148.0.1 to 226.148.31.254226.148.31.2558,190
162226.148.32.0/19226.148.32.1 to 226.148.63.254226.148.63.2558,190
163226.148.64.0/19226.148.64.1 to 226.148.95.254226.148.95.2558,190
164226.148.96.0/19226.148.96.1 to 226.148.127.254226.148.127.2558,190
165226.148.128.0/19226.148.128.1 to 226.148.159.254226.148.159.2558,190
166226.148.160.0/19226.148.160.1 to 226.148.191.254226.148.191.2558,190
167226.148.192.0/19226.148.192.1 to 226.148.223.254226.148.223.2558,190
168226.148.224.0/19226.148.224.1 to 226.148.255.254226.148.255.2558,190
169226.149.0.0/19226.149.0.1 to 226.149.31.254226.149.31.2558,190
170226.149.32.0/19226.149.32.1 to 226.149.63.254226.149.63.2558,190
171226.149.64.0/19226.149.64.1 to 226.149.95.254226.149.95.2558,190
172226.149.96.0/19226.149.96.1 to 226.149.127.254226.149.127.2558,190
173226.149.128.0/19226.149.128.1 to 226.149.159.254226.149.159.2558,190
174226.149.160.0/19226.149.160.1 to 226.149.191.254226.149.191.2558,190
175226.149.192.0/19226.149.192.1 to 226.149.223.254226.149.223.2558,190
176226.149.224.0/19226.149.224.1 to 226.149.255.254226.149.255.2558,190
177226.150.0.0/19226.150.0.1 to 226.150.31.254226.150.31.2558,190
178226.150.32.0/19226.150.32.1 to 226.150.63.254226.150.63.2558,190
179226.150.64.0/19226.150.64.1 to 226.150.95.254226.150.95.2558,190
180226.150.96.0/19226.150.96.1 to 226.150.127.254226.150.127.2558,190
181226.150.128.0/19226.150.128.1 to 226.150.159.254226.150.159.2558,190
182226.150.160.0/19226.150.160.1 to 226.150.191.254226.150.191.2558,190
183226.150.192.0/19226.150.192.1 to 226.150.223.254226.150.223.2558,190
184226.150.224.0/19226.150.224.1 to 226.150.255.254226.150.255.2558,190
185226.151.0.0/19226.151.0.1 to 226.151.31.254226.151.31.2558,190
186226.151.32.0/19226.151.32.1 to 226.151.63.254226.151.63.2558,190
187226.151.64.0/19226.151.64.1 to 226.151.95.254226.151.95.2558,190
188226.151.96.0/19226.151.96.1 to 226.151.127.254226.151.127.2558,190
189226.151.128.0/19226.151.128.1 to 226.151.159.254226.151.159.2558,190
190226.151.160.0/19226.151.160.1 to 226.151.191.254226.151.191.2558,190
191226.151.192.0/19226.151.192.1 to 226.151.223.254226.151.223.2558,190
192226.151.224.0/19226.151.224.1 to 226.151.255.254226.151.255.2558,190
193226.152.0.0/19226.152.0.1 to 226.152.31.254226.152.31.2558,190
194226.152.32.0/19226.152.32.1 to 226.152.63.254226.152.63.2558,190
195226.152.64.0/19226.152.64.1 to 226.152.95.254226.152.95.2558,190
196226.152.96.0/19226.152.96.1 to 226.152.127.254226.152.127.2558,190
197226.152.128.0/19226.152.128.1 to 226.152.159.254226.152.159.2558,190
198226.152.160.0/19226.152.160.1 to 226.152.191.254226.152.191.2558,190
199226.152.192.0/19226.152.192.1 to 226.152.223.254226.152.223.2558,190
200226.152.224.0/19226.152.224.1 to 226.152.255.254226.152.255.2558,190
201226.153.0.0/19226.153.0.1 to 226.153.31.254226.153.31.2558,190
202226.153.32.0/19226.153.32.1 to 226.153.63.254226.153.63.2558,190
203226.153.64.0/19226.153.64.1 to 226.153.95.254226.153.95.2558,190
204226.153.96.0/19226.153.96.1 to 226.153.127.254226.153.127.2558,190
205226.153.128.0/19226.153.128.1 to 226.153.159.254226.153.159.2558,190
206226.153.160.0/19226.153.160.1 to 226.153.191.254226.153.191.2558,190
207226.153.192.0/19226.153.192.1 to 226.153.223.254226.153.223.2558,190
208226.153.224.0/19226.153.224.1 to 226.153.255.254226.153.255.2558,190
209226.154.0.0/19226.154.0.1 to 226.154.31.254226.154.31.2558,190
210226.154.32.0/19226.154.32.1 to 226.154.63.254226.154.63.2558,190
211226.154.64.0/19226.154.64.1 to 226.154.95.254226.154.95.2558,190
212226.154.96.0/19226.154.96.1 to 226.154.127.254226.154.127.2558,190
213226.154.128.0/19226.154.128.1 to 226.154.159.254226.154.159.2558,190
214226.154.160.0/19226.154.160.1 to 226.154.191.254226.154.191.2558,190
215226.154.192.0/19226.154.192.1 to 226.154.223.254226.154.223.2558,190
216226.154.224.0/19226.154.224.1 to 226.154.255.254226.154.255.2558,190
217226.155.0.0/19226.155.0.1 to 226.155.31.254226.155.31.2558,190
218226.155.32.0/19226.155.32.1 to 226.155.63.254226.155.63.2558,190
219226.155.64.0/19226.155.64.1 to 226.155.95.254226.155.95.2558,190
220226.155.96.0/19226.155.96.1 to 226.155.127.254226.155.127.2558,190
221226.155.128.0/19226.155.128.1 to 226.155.159.254226.155.159.2558,190
222226.155.160.0/19226.155.160.1 to 226.155.191.254226.155.191.2558,190
223226.155.192.0/19226.155.192.1 to 226.155.223.254226.155.223.2558,190
224226.155.224.0/19226.155.224.1 to 226.155.255.254226.155.255.2558,190
225226.156.0.0/19226.156.0.1 to 226.156.31.254226.156.31.2558,190
226226.156.32.0/19226.156.32.1 to 226.156.63.254226.156.63.2558,190
227226.156.64.0/19226.156.64.1 to 226.156.95.254226.156.95.2558,190
228226.156.96.0/19226.156.96.1 to 226.156.127.254226.156.127.2558,190
229226.156.128.0/19226.156.128.1 to 226.156.159.254226.156.159.2558,190
230226.156.160.0/19226.156.160.1 to 226.156.191.254226.156.191.2558,190
231226.156.192.0/19226.156.192.1 to 226.156.223.254226.156.223.2558,190
232226.156.224.0/19226.156.224.1 to 226.156.255.254226.156.255.2558,190
233226.157.0.0/19226.157.0.1 to 226.157.31.254226.157.31.2558,190
234226.157.32.0/19226.157.32.1 to 226.157.63.254226.157.63.2558,190
235226.157.64.0/19226.157.64.1 to 226.157.95.254226.157.95.2558,190
236226.157.96.0/19226.157.96.1 to 226.157.127.254226.157.127.2558,190
237226.157.128.0/19226.157.128.1 to 226.157.159.254226.157.159.2558,190
238226.157.160.0/19226.157.160.1 to 226.157.191.254226.157.191.2558,190
239226.157.192.0/19226.157.192.1 to 226.157.223.254226.157.223.2558,190
240226.157.224.0/19226.157.224.1 to 226.157.255.254226.157.255.2558,190
241226.158.0.0/19226.158.0.1 to 226.158.31.254226.158.31.2558,190
242226.158.32.0/19226.158.32.1 to 226.158.63.254226.158.63.2558,190
243226.158.64.0/19226.158.64.1 to 226.158.95.254226.158.95.2558,190
244226.158.96.0/19226.158.96.1 to 226.158.127.254226.158.127.2558,190
245226.158.128.0/19226.158.128.1 to 226.158.159.254226.158.159.2558,190
246226.158.160.0/19226.158.160.1 to 226.158.191.254226.158.191.2558,190
247226.158.192.0/19226.158.192.1 to 226.158.223.254226.158.223.2558,190
248226.158.224.0/19226.158.224.1 to 226.158.255.254226.158.255.2558,190
249226.159.0.0/19226.159.0.1 to 226.159.31.254226.159.31.2558,190
250226.159.32.0/19226.159.32.1 to 226.159.63.254226.159.63.2558,190
251226.159.64.0/19226.159.64.1 to 226.159.95.254226.159.95.2558,190
252226.159.96.0/19226.159.96.1 to 226.159.127.254226.159.127.2558,190
253226.159.128.0/19226.159.128.1 to 226.159.159.254226.159.159.2558,190
254226.159.160.0/19226.159.160.1 to 226.159.191.254226.159.191.2558,190
255226.159.192.0/19226.159.192.1 to 226.159.223.254226.159.223.2558,190
256226.159.224.0/19226.159.224.1 to 226.159.255.254226.159.255.2558,190

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.