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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.

Network224.0.0.0/4
Usable hosts268,435,454
Subnet mask240.0.0.0
Addresses268,435,456
Network address
224.0.0.0
Broadcast address
239.255.255.255
First usable
224.0.0.1
Last usable
239.255.255.254
Usable hosts
268,435,454 (268,435,456 less the network and broadcast addresses)
Subnet mask
240.0.0.0
Wildcard mask
15.255.255.255 (Cisco ACLs, OSPF)
Prefix length
/4
Type
Multicast 224.0.0.0/4
One-to-many traffic, such as IPTV and routing protocols
Old class
D (multicast)
As numbers
Hex E0000000 · Integer 3758096384 to 4026531839
Reverse DNS zones
224.in-addr.arpa
225.in-addr.arpa
226.in-addr.arpa
227.in-addr.arpa
228.in-addr.arpa
229.in-addr.arpa
230.in-addr.arpa
231.in-addr.arpa
232.in-addr.arpa
233.in-addr.arpa
234.in-addr.arpa
235.in-addr.arpa
236.in-addr.arpa
237.in-addr.arpa
238.in-addr.arpa
239.in-addr.arpa
/4 is not on a 8-bit boundary, so it takes 16 /8 zones.
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address11100000.00000000.00000000.00000000224.0.0.0
Subnet mask11110000.00000000.00000000.00000000240.0.0.0
Network11100000.00000000.00000000.00000000224.0.0.0
Broadcast11101111.11111111.11111111.11111111239.255.255.255
Split into smaller subnets/13
/5 (2)/6 (4)/7 (8)/8 (16)/9 (32)/10 (64)/11 (128)/12 (256)/13 (512)/14 (1,024)/15 (2,048)/16 (4,096)

224.0.0.0/4 makes 512 subnets of /13; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
1224.0.0.0/13224.0.0.1 to 224.7.255.254224.7.255.255524,286
2224.8.0.0/13224.8.0.1 to 224.15.255.254224.15.255.255524,286
3224.16.0.0/13224.16.0.1 to 224.23.255.254224.23.255.255524,286
4224.24.0.0/13224.24.0.1 to 224.31.255.254224.31.255.255524,286
5224.32.0.0/13224.32.0.1 to 224.39.255.254224.39.255.255524,286
6224.40.0.0/13224.40.0.1 to 224.47.255.254224.47.255.255524,286
7224.48.0.0/13224.48.0.1 to 224.55.255.254224.55.255.255524,286
8224.56.0.0/13224.56.0.1 to 224.63.255.254224.63.255.255524,286
9224.64.0.0/13224.64.0.1 to 224.71.255.254224.71.255.255524,286
10224.72.0.0/13224.72.0.1 to 224.79.255.254224.79.255.255524,286
11224.80.0.0/13224.80.0.1 to 224.87.255.254224.87.255.255524,286
12224.88.0.0/13224.88.0.1 to 224.95.255.254224.95.255.255524,286
13224.96.0.0/13224.96.0.1 to 224.103.255.254224.103.255.255524,286
14224.104.0.0/13224.104.0.1 to 224.111.255.254224.111.255.255524,286
15224.112.0.0/13224.112.0.1 to 224.119.255.254224.119.255.255524,286
16224.120.0.0/13224.120.0.1 to 224.127.255.254224.127.255.255524,286
17224.128.0.0/13224.128.0.1 to 224.135.255.254224.135.255.255524,286
18224.136.0.0/13224.136.0.1 to 224.143.255.254224.143.255.255524,286
19224.144.0.0/13224.144.0.1 to 224.151.255.254224.151.255.255524,286
20224.152.0.0/13224.152.0.1 to 224.159.255.254224.159.255.255524,286
21224.160.0.0/13224.160.0.1 to 224.167.255.254224.167.255.255524,286
22224.168.0.0/13224.168.0.1 to 224.175.255.254224.175.255.255524,286
23224.176.0.0/13224.176.0.1 to 224.183.255.254224.183.255.255524,286
24224.184.0.0/13224.184.0.1 to 224.191.255.254224.191.255.255524,286
25224.192.0.0/13224.192.0.1 to 224.199.255.254224.199.255.255524,286
26224.200.0.0/13224.200.0.1 to 224.207.255.254224.207.255.255524,286
27224.208.0.0/13224.208.0.1 to 224.215.255.254224.215.255.255524,286
28224.216.0.0/13224.216.0.1 to 224.223.255.254224.223.255.255524,286
29224.224.0.0/13224.224.0.1 to 224.231.255.254224.231.255.255524,286
30224.232.0.0/13224.232.0.1 to 224.239.255.254224.239.255.255524,286
31224.240.0.0/13224.240.0.1 to 224.247.255.254224.247.255.255524,286
32224.248.0.0/13224.248.0.1 to 224.255.255.254224.255.255.255524,286
33225.0.0.0/13225.0.0.1 to 225.7.255.254225.7.255.255524,286
34225.8.0.0/13225.8.0.1 to 225.15.255.254225.15.255.255524,286
35225.16.0.0/13225.16.0.1 to 225.23.255.254225.23.255.255524,286
36225.24.0.0/13225.24.0.1 to 225.31.255.254225.31.255.255524,286
37225.32.0.0/13225.32.0.1 to 225.39.255.254225.39.255.255524,286
38225.40.0.0/13225.40.0.1 to 225.47.255.254225.47.255.255524,286
39225.48.0.0/13225.48.0.1 to 225.55.255.254225.55.255.255524,286
40225.56.0.0/13225.56.0.1 to 225.63.255.254225.63.255.255524,286
41225.64.0.0/13225.64.0.1 to 225.71.255.254225.71.255.255524,286
42225.72.0.0/13225.72.0.1 to 225.79.255.254225.79.255.255524,286
43225.80.0.0/13225.80.0.1 to 225.87.255.254225.87.255.255524,286
44225.88.0.0/13225.88.0.1 to 225.95.255.254225.95.255.255524,286
45225.96.0.0/13225.96.0.1 to 225.103.255.254225.103.255.255524,286
46225.104.0.0/13225.104.0.1 to 225.111.255.254225.111.255.255524,286
47225.112.0.0/13225.112.0.1 to 225.119.255.254225.119.255.255524,286
48225.120.0.0/13225.120.0.1 to 225.127.255.254225.127.255.255524,286
49225.128.0.0/13225.128.0.1 to 225.135.255.254225.135.255.255524,286
50225.136.0.0/13225.136.0.1 to 225.143.255.254225.143.255.255524,286
51225.144.0.0/13225.144.0.1 to 225.151.255.254225.151.255.255524,286
52225.152.0.0/13225.152.0.1 to 225.159.255.254225.159.255.255524,286
53225.160.0.0/13225.160.0.1 to 225.167.255.254225.167.255.255524,286
54225.168.0.0/13225.168.0.1 to 225.175.255.254225.175.255.255524,286
55225.176.0.0/13225.176.0.1 to 225.183.255.254225.183.255.255524,286
56225.184.0.0/13225.184.0.1 to 225.191.255.254225.191.255.255524,286
57225.192.0.0/13225.192.0.1 to 225.199.255.254225.199.255.255524,286
58225.200.0.0/13225.200.0.1 to 225.207.255.254225.207.255.255524,286
59225.208.0.0/13225.208.0.1 to 225.215.255.254225.215.255.255524,286
60225.216.0.0/13225.216.0.1 to 225.223.255.254225.223.255.255524,286
61225.224.0.0/13225.224.0.1 to 225.231.255.254225.231.255.255524,286
62225.232.0.0/13225.232.0.1 to 225.239.255.254225.239.255.255524,286
63225.240.0.0/13225.240.0.1 to 225.247.255.254225.247.255.255524,286
64225.248.0.0/13225.248.0.1 to 225.255.255.254225.255.255.255524,286
65226.0.0.0/13226.0.0.1 to 226.7.255.254226.7.255.255524,286
66226.8.0.0/13226.8.0.1 to 226.15.255.254226.15.255.255524,286
67226.16.0.0/13226.16.0.1 to 226.23.255.254226.23.255.255524,286
68226.24.0.0/13226.24.0.1 to 226.31.255.254226.31.255.255524,286
69226.32.0.0/13226.32.0.1 to 226.39.255.254226.39.255.255524,286
70226.40.0.0/13226.40.0.1 to 226.47.255.254226.47.255.255524,286
71226.48.0.0/13226.48.0.1 to 226.55.255.254226.55.255.255524,286
72226.56.0.0/13226.56.0.1 to 226.63.255.254226.63.255.255524,286
73226.64.0.0/13226.64.0.1 to 226.71.255.254226.71.255.255524,286
74226.72.0.0/13226.72.0.1 to 226.79.255.254226.79.255.255524,286
75226.80.0.0/13226.80.0.1 to 226.87.255.254226.87.255.255524,286
76226.88.0.0/13226.88.0.1 to 226.95.255.254226.95.255.255524,286
77226.96.0.0/13226.96.0.1 to 226.103.255.254226.103.255.255524,286
78226.104.0.0/13226.104.0.1 to 226.111.255.254226.111.255.255524,286
79226.112.0.0/13226.112.0.1 to 226.119.255.254226.119.255.255524,286
80226.120.0.0/13226.120.0.1 to 226.127.255.254226.127.255.255524,286
81226.128.0.0/13226.128.0.1 to 226.135.255.254226.135.255.255524,286
82226.136.0.0/13226.136.0.1 to 226.143.255.254226.143.255.255524,286
83226.144.0.0/13226.144.0.1 to 226.151.255.254226.151.255.255524,286
84226.152.0.0/13226.152.0.1 to 226.159.255.254226.159.255.255524,286
85226.160.0.0/13226.160.0.1 to 226.167.255.254226.167.255.255524,286
86226.168.0.0/13226.168.0.1 to 226.175.255.254226.175.255.255524,286
87226.176.0.0/13226.176.0.1 to 226.183.255.254226.183.255.255524,286
88226.184.0.0/13226.184.0.1 to 226.191.255.254226.191.255.255524,286
89226.192.0.0/13226.192.0.1 to 226.199.255.254226.199.255.255524,286
90226.200.0.0/13226.200.0.1 to 226.207.255.254226.207.255.255524,286
91226.208.0.0/13226.208.0.1 to 226.215.255.254226.215.255.255524,286
92226.216.0.0/13226.216.0.1 to 226.223.255.254226.223.255.255524,286
93226.224.0.0/13226.224.0.1 to 226.231.255.254226.231.255.255524,286
94226.232.0.0/13226.232.0.1 to 226.239.255.254226.239.255.255524,286
95226.240.0.0/13226.240.0.1 to 226.247.255.254226.247.255.255524,286
96226.248.0.0/13226.248.0.1 to 226.255.255.254226.255.255.255524,286
97227.0.0.0/13227.0.0.1 to 227.7.255.254227.7.255.255524,286
98227.8.0.0/13227.8.0.1 to 227.15.255.254227.15.255.255524,286
99227.16.0.0/13227.16.0.1 to 227.23.255.254227.23.255.255524,286
100227.24.0.0/13227.24.0.1 to 227.31.255.254227.31.255.255524,286
101227.32.0.0/13227.32.0.1 to 227.39.255.254227.39.255.255524,286
102227.40.0.0/13227.40.0.1 to 227.47.255.254227.47.255.255524,286
103227.48.0.0/13227.48.0.1 to 227.55.255.254227.55.255.255524,286
104227.56.0.0/13227.56.0.1 to 227.63.255.254227.63.255.255524,286
105227.64.0.0/13227.64.0.1 to 227.71.255.254227.71.255.255524,286
106227.72.0.0/13227.72.0.1 to 227.79.255.254227.79.255.255524,286
107227.80.0.0/13227.80.0.1 to 227.87.255.254227.87.255.255524,286
108227.88.0.0/13227.88.0.1 to 227.95.255.254227.95.255.255524,286
109227.96.0.0/13227.96.0.1 to 227.103.255.254227.103.255.255524,286
110227.104.0.0/13227.104.0.1 to 227.111.255.254227.111.255.255524,286
111227.112.0.0/13227.112.0.1 to 227.119.255.254227.119.255.255524,286
112227.120.0.0/13227.120.0.1 to 227.127.255.254227.127.255.255524,286
113227.128.0.0/13227.128.0.1 to 227.135.255.254227.135.255.255524,286
114227.136.0.0/13227.136.0.1 to 227.143.255.254227.143.255.255524,286
115227.144.0.0/13227.144.0.1 to 227.151.255.254227.151.255.255524,286
116227.152.0.0/13227.152.0.1 to 227.159.255.254227.159.255.255524,286
117227.160.0.0/13227.160.0.1 to 227.167.255.254227.167.255.255524,286
118227.168.0.0/13227.168.0.1 to 227.175.255.254227.175.255.255524,286
119227.176.0.0/13227.176.0.1 to 227.183.255.254227.183.255.255524,286
120227.184.0.0/13227.184.0.1 to 227.191.255.254227.191.255.255524,286
121227.192.0.0/13227.192.0.1 to 227.199.255.254227.199.255.255524,286
122227.200.0.0/13227.200.0.1 to 227.207.255.254227.207.255.255524,286
123227.208.0.0/13227.208.0.1 to 227.215.255.254227.215.255.255524,286
124227.216.0.0/13227.216.0.1 to 227.223.255.254227.223.255.255524,286
125227.224.0.0/13227.224.0.1 to 227.231.255.254227.231.255.255524,286
126227.232.0.0/13227.232.0.1 to 227.239.255.254227.239.255.255524,286
127227.240.0.0/13227.240.0.1 to 227.247.255.254227.247.255.255524,286
128227.248.0.0/13227.248.0.1 to 227.255.255.254227.255.255.255524,286
129228.0.0.0/13228.0.0.1 to 228.7.255.254228.7.255.255524,286
130228.8.0.0/13228.8.0.1 to 228.15.255.254228.15.255.255524,286
131228.16.0.0/13228.16.0.1 to 228.23.255.254228.23.255.255524,286
132228.24.0.0/13228.24.0.1 to 228.31.255.254228.31.255.255524,286
133228.32.0.0/13228.32.0.1 to 228.39.255.254228.39.255.255524,286
134228.40.0.0/13228.40.0.1 to 228.47.255.254228.47.255.255524,286
135228.48.0.0/13228.48.0.1 to 228.55.255.254228.55.255.255524,286
136228.56.0.0/13228.56.0.1 to 228.63.255.254228.63.255.255524,286
137228.64.0.0/13228.64.0.1 to 228.71.255.254228.71.255.255524,286
138228.72.0.0/13228.72.0.1 to 228.79.255.254228.79.255.255524,286
139228.80.0.0/13228.80.0.1 to 228.87.255.254228.87.255.255524,286
140228.88.0.0/13228.88.0.1 to 228.95.255.254228.95.255.255524,286
141228.96.0.0/13228.96.0.1 to 228.103.255.254228.103.255.255524,286
142228.104.0.0/13228.104.0.1 to 228.111.255.254228.111.255.255524,286
143228.112.0.0/13228.112.0.1 to 228.119.255.254228.119.255.255524,286
144228.120.0.0/13228.120.0.1 to 228.127.255.254228.127.255.255524,286
145228.128.0.0/13228.128.0.1 to 228.135.255.254228.135.255.255524,286
146228.136.0.0/13228.136.0.1 to 228.143.255.254228.143.255.255524,286
147228.144.0.0/13228.144.0.1 to 228.151.255.254228.151.255.255524,286
148228.152.0.0/13228.152.0.1 to 228.159.255.254228.159.255.255524,286
149228.160.0.0/13228.160.0.1 to 228.167.255.254228.167.255.255524,286
150228.168.0.0/13228.168.0.1 to 228.175.255.254228.175.255.255524,286
151228.176.0.0/13228.176.0.1 to 228.183.255.254228.183.255.255524,286
152228.184.0.0/13228.184.0.1 to 228.191.255.254228.191.255.255524,286
153228.192.0.0/13228.192.0.1 to 228.199.255.254228.199.255.255524,286
154228.200.0.0/13228.200.0.1 to 228.207.255.254228.207.255.255524,286
155228.208.0.0/13228.208.0.1 to 228.215.255.254228.215.255.255524,286
156228.216.0.0/13228.216.0.1 to 228.223.255.254228.223.255.255524,286
157228.224.0.0/13228.224.0.1 to 228.231.255.254228.231.255.255524,286
158228.232.0.0/13228.232.0.1 to 228.239.255.254228.239.255.255524,286
159228.240.0.0/13228.240.0.1 to 228.247.255.254228.247.255.255524,286
160228.248.0.0/13228.248.0.1 to 228.255.255.254228.255.255.255524,286
161229.0.0.0/13229.0.0.1 to 229.7.255.254229.7.255.255524,286
162229.8.0.0/13229.8.0.1 to 229.15.255.254229.15.255.255524,286
163229.16.0.0/13229.16.0.1 to 229.23.255.254229.23.255.255524,286
164229.24.0.0/13229.24.0.1 to 229.31.255.254229.31.255.255524,286
165229.32.0.0/13229.32.0.1 to 229.39.255.254229.39.255.255524,286
166229.40.0.0/13229.40.0.1 to 229.47.255.254229.47.255.255524,286
167229.48.0.0/13229.48.0.1 to 229.55.255.254229.55.255.255524,286
168229.56.0.0/13229.56.0.1 to 229.63.255.254229.63.255.255524,286
169229.64.0.0/13229.64.0.1 to 229.71.255.254229.71.255.255524,286
170229.72.0.0/13229.72.0.1 to 229.79.255.254229.79.255.255524,286
171229.80.0.0/13229.80.0.1 to 229.87.255.254229.87.255.255524,286
172229.88.0.0/13229.88.0.1 to 229.95.255.254229.95.255.255524,286
173229.96.0.0/13229.96.0.1 to 229.103.255.254229.103.255.255524,286
174229.104.0.0/13229.104.0.1 to 229.111.255.254229.111.255.255524,286
175229.112.0.0/13229.112.0.1 to 229.119.255.254229.119.255.255524,286
176229.120.0.0/13229.120.0.1 to 229.127.255.254229.127.255.255524,286
177229.128.0.0/13229.128.0.1 to 229.135.255.254229.135.255.255524,286
178229.136.0.0/13229.136.0.1 to 229.143.255.254229.143.255.255524,286
179229.144.0.0/13229.144.0.1 to 229.151.255.254229.151.255.255524,286
180229.152.0.0/13229.152.0.1 to 229.159.255.254229.159.255.255524,286
181229.160.0.0/13229.160.0.1 to 229.167.255.254229.167.255.255524,286
182229.168.0.0/13229.168.0.1 to 229.175.255.254229.175.255.255524,286
183229.176.0.0/13229.176.0.1 to 229.183.255.254229.183.255.255524,286
184229.184.0.0/13229.184.0.1 to 229.191.255.254229.191.255.255524,286
185229.192.0.0/13229.192.0.1 to 229.199.255.254229.199.255.255524,286
186229.200.0.0/13229.200.0.1 to 229.207.255.254229.207.255.255524,286
187229.208.0.0/13229.208.0.1 to 229.215.255.254229.215.255.255524,286
188229.216.0.0/13229.216.0.1 to 229.223.255.254229.223.255.255524,286
189229.224.0.0/13229.224.0.1 to 229.231.255.254229.231.255.255524,286
190229.232.0.0/13229.232.0.1 to 229.239.255.254229.239.255.255524,286
191229.240.0.0/13229.240.0.1 to 229.247.255.254229.247.255.255524,286
192229.248.0.0/13229.248.0.1 to 229.255.255.254229.255.255.255524,286
193230.0.0.0/13230.0.0.1 to 230.7.255.254230.7.255.255524,286
194230.8.0.0/13230.8.0.1 to 230.15.255.254230.15.255.255524,286
195230.16.0.0/13230.16.0.1 to 230.23.255.254230.23.255.255524,286
196230.24.0.0/13230.24.0.1 to 230.31.255.254230.31.255.255524,286
197230.32.0.0/13230.32.0.1 to 230.39.255.254230.39.255.255524,286
198230.40.0.0/13230.40.0.1 to 230.47.255.254230.47.255.255524,286
199230.48.0.0/13230.48.0.1 to 230.55.255.254230.55.255.255524,286
200230.56.0.0/13230.56.0.1 to 230.63.255.254230.63.255.255524,286
201230.64.0.0/13230.64.0.1 to 230.71.255.254230.71.255.255524,286
202230.72.0.0/13230.72.0.1 to 230.79.255.254230.79.255.255524,286
203230.80.0.0/13230.80.0.1 to 230.87.255.254230.87.255.255524,286
204230.88.0.0/13230.88.0.1 to 230.95.255.254230.95.255.255524,286
205230.96.0.0/13230.96.0.1 to 230.103.255.254230.103.255.255524,286
206230.104.0.0/13230.104.0.1 to 230.111.255.254230.111.255.255524,286
207230.112.0.0/13230.112.0.1 to 230.119.255.254230.119.255.255524,286
208230.120.0.0/13230.120.0.1 to 230.127.255.254230.127.255.255524,286
209230.128.0.0/13230.128.0.1 to 230.135.255.254230.135.255.255524,286
210230.136.0.0/13230.136.0.1 to 230.143.255.254230.143.255.255524,286
211230.144.0.0/13230.144.0.1 to 230.151.255.254230.151.255.255524,286
212230.152.0.0/13230.152.0.1 to 230.159.255.254230.159.255.255524,286
213230.160.0.0/13230.160.0.1 to 230.167.255.254230.167.255.255524,286
214230.168.0.0/13230.168.0.1 to 230.175.255.254230.175.255.255524,286
215230.176.0.0/13230.176.0.1 to 230.183.255.254230.183.255.255524,286
216230.184.0.0/13230.184.0.1 to 230.191.255.254230.191.255.255524,286
217230.192.0.0/13230.192.0.1 to 230.199.255.254230.199.255.255524,286
218230.200.0.0/13230.200.0.1 to 230.207.255.254230.207.255.255524,286
219230.208.0.0/13230.208.0.1 to 230.215.255.254230.215.255.255524,286
220230.216.0.0/13230.216.0.1 to 230.223.255.254230.223.255.255524,286
221230.224.0.0/13230.224.0.1 to 230.231.255.254230.231.255.255524,286
222230.232.0.0/13230.232.0.1 to 230.239.255.254230.239.255.255524,286
223230.240.0.0/13230.240.0.1 to 230.247.255.254230.247.255.255524,286
224230.248.0.0/13230.248.0.1 to 230.255.255.254230.255.255.255524,286
225231.0.0.0/13231.0.0.1 to 231.7.255.254231.7.255.255524,286
226231.8.0.0/13231.8.0.1 to 231.15.255.254231.15.255.255524,286
227231.16.0.0/13231.16.0.1 to 231.23.255.254231.23.255.255524,286
228231.24.0.0/13231.24.0.1 to 231.31.255.254231.31.255.255524,286
229231.32.0.0/13231.32.0.1 to 231.39.255.254231.39.255.255524,286
230231.40.0.0/13231.40.0.1 to 231.47.255.254231.47.255.255524,286
231231.48.0.0/13231.48.0.1 to 231.55.255.254231.55.255.255524,286
232231.56.0.0/13231.56.0.1 to 231.63.255.254231.63.255.255524,286
233231.64.0.0/13231.64.0.1 to 231.71.255.254231.71.255.255524,286
234231.72.0.0/13231.72.0.1 to 231.79.255.254231.79.255.255524,286
235231.80.0.0/13231.80.0.1 to 231.87.255.254231.87.255.255524,286
236231.88.0.0/13231.88.0.1 to 231.95.255.254231.95.255.255524,286
237231.96.0.0/13231.96.0.1 to 231.103.255.254231.103.255.255524,286
238231.104.0.0/13231.104.0.1 to 231.111.255.254231.111.255.255524,286
239231.112.0.0/13231.112.0.1 to 231.119.255.254231.119.255.255524,286
240231.120.0.0/13231.120.0.1 to 231.127.255.254231.127.255.255524,286
241231.128.0.0/13231.128.0.1 to 231.135.255.254231.135.255.255524,286
242231.136.0.0/13231.136.0.1 to 231.143.255.254231.143.255.255524,286
243231.144.0.0/13231.144.0.1 to 231.151.255.254231.151.255.255524,286
244231.152.0.0/13231.152.0.1 to 231.159.255.254231.159.255.255524,286
245231.160.0.0/13231.160.0.1 to 231.167.255.254231.167.255.255524,286
246231.168.0.0/13231.168.0.1 to 231.175.255.254231.175.255.255524,286
247231.176.0.0/13231.176.0.1 to 231.183.255.254231.183.255.255524,286
248231.184.0.0/13231.184.0.1 to 231.191.255.254231.191.255.255524,286
249231.192.0.0/13231.192.0.1 to 231.199.255.254231.199.255.255524,286
250231.200.0.0/13231.200.0.1 to 231.207.255.254231.207.255.255524,286
251231.208.0.0/13231.208.0.1 to 231.215.255.254231.215.255.255524,286
252231.216.0.0/13231.216.0.1 to 231.223.255.254231.223.255.255524,286
253231.224.0.0/13231.224.0.1 to 231.231.255.254231.231.255.255524,286
254231.232.0.0/13231.232.0.1 to 231.239.255.254231.239.255.255524,286
255231.240.0.0/13231.240.0.1 to 231.247.255.254231.247.255.255524,286
256231.248.0.0/13231.248.0.1 to 231.255.255.254231.255.255.255524,286

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.