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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.

Network227.4.0.0/14
Usable hosts262,142
Subnet mask255.252.0.0
Addresses262,144
Network address
227.4.0.0
Broadcast address
227.7.255.255
First usable
227.4.0.1
Last usable
227.7.255.254
Usable hosts
262,142 (262,144 less the network and broadcast addresses)
Subnet mask
255.252.0.0
Wildcard mask
0.3.255.255 (Cisco ACLs, OSPF)
Prefix length
/14
Type
Multicast 224.0.0.0/4
One-to-many traffic, such as IPTV and routing protocols
Old class
D (multicast)
As numbers
Hex E3040000 · Integer 3808690176 to 3808952319
Reverse DNS zones
4.227.in-addr.arpa
5.227.in-addr.arpa
6.227.in-addr.arpa
7.227.in-addr.arpa
/14 is not on a 8-bit boundary, so it takes 4 /16 zones.
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address11100011.00000100.00000000.00000000227.4.0.0
Subnet mask11111111.11111100.00000000.00000000255.252.0.0
Network11100011.00000100.00000000.00000000227.4.0.0
Broadcast11100011.00000111.11111111.11111111227.7.255.255
Split into smaller subnets/26
/15 (2)/16 (4)/17 (8)/18 (16)/19 (32)/20 (64)/21 (128)/22 (256)/23 (512)/24 (1,024)/25 (2,048)/26 (4,096)

227.4.0.0/14 makes 4,096 subnets of /26; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
1227.4.0.0/26227.4.0.1 to 227.4.0.62227.4.0.6362
2227.4.0.64/26227.4.0.65 to 227.4.0.126227.4.0.12762
3227.4.0.128/26227.4.0.129 to 227.4.0.190227.4.0.19162
4227.4.0.192/26227.4.0.193 to 227.4.0.254227.4.0.25562
5227.4.1.0/26227.4.1.1 to 227.4.1.62227.4.1.6362
6227.4.1.64/26227.4.1.65 to 227.4.1.126227.4.1.12762
7227.4.1.128/26227.4.1.129 to 227.4.1.190227.4.1.19162
8227.4.1.192/26227.4.1.193 to 227.4.1.254227.4.1.25562
9227.4.2.0/26227.4.2.1 to 227.4.2.62227.4.2.6362
10227.4.2.64/26227.4.2.65 to 227.4.2.126227.4.2.12762
11227.4.2.128/26227.4.2.129 to 227.4.2.190227.4.2.19162
12227.4.2.192/26227.4.2.193 to 227.4.2.254227.4.2.25562
13227.4.3.0/26227.4.3.1 to 227.4.3.62227.4.3.6362
14227.4.3.64/26227.4.3.65 to 227.4.3.126227.4.3.12762
15227.4.3.128/26227.4.3.129 to 227.4.3.190227.4.3.19162
16227.4.3.192/26227.4.3.193 to 227.4.3.254227.4.3.25562
17227.4.4.0/26227.4.4.1 to 227.4.4.62227.4.4.6362
18227.4.4.64/26227.4.4.65 to 227.4.4.126227.4.4.12762
19227.4.4.128/26227.4.4.129 to 227.4.4.190227.4.4.19162
20227.4.4.192/26227.4.4.193 to 227.4.4.254227.4.4.25562
21227.4.5.0/26227.4.5.1 to 227.4.5.62227.4.5.6362
22227.4.5.64/26227.4.5.65 to 227.4.5.126227.4.5.12762
23227.4.5.128/26227.4.5.129 to 227.4.5.190227.4.5.19162
24227.4.5.192/26227.4.5.193 to 227.4.5.254227.4.5.25562
25227.4.6.0/26227.4.6.1 to 227.4.6.62227.4.6.6362
26227.4.6.64/26227.4.6.65 to 227.4.6.126227.4.6.12762
27227.4.6.128/26227.4.6.129 to 227.4.6.190227.4.6.19162
28227.4.6.192/26227.4.6.193 to 227.4.6.254227.4.6.25562
29227.4.7.0/26227.4.7.1 to 227.4.7.62227.4.7.6362
30227.4.7.64/26227.4.7.65 to 227.4.7.126227.4.7.12762
31227.4.7.128/26227.4.7.129 to 227.4.7.190227.4.7.19162
32227.4.7.192/26227.4.7.193 to 227.4.7.254227.4.7.25562
33227.4.8.0/26227.4.8.1 to 227.4.8.62227.4.8.6362
34227.4.8.64/26227.4.8.65 to 227.4.8.126227.4.8.12762
35227.4.8.128/26227.4.8.129 to 227.4.8.190227.4.8.19162
36227.4.8.192/26227.4.8.193 to 227.4.8.254227.4.8.25562
37227.4.9.0/26227.4.9.1 to 227.4.9.62227.4.9.6362
38227.4.9.64/26227.4.9.65 to 227.4.9.126227.4.9.12762
39227.4.9.128/26227.4.9.129 to 227.4.9.190227.4.9.19162
40227.4.9.192/26227.4.9.193 to 227.4.9.254227.4.9.25562
41227.4.10.0/26227.4.10.1 to 227.4.10.62227.4.10.6362
42227.4.10.64/26227.4.10.65 to 227.4.10.126227.4.10.12762
43227.4.10.128/26227.4.10.129 to 227.4.10.190227.4.10.19162
44227.4.10.192/26227.4.10.193 to 227.4.10.254227.4.10.25562
45227.4.11.0/26227.4.11.1 to 227.4.11.62227.4.11.6362
46227.4.11.64/26227.4.11.65 to 227.4.11.126227.4.11.12762
47227.4.11.128/26227.4.11.129 to 227.4.11.190227.4.11.19162
48227.4.11.192/26227.4.11.193 to 227.4.11.254227.4.11.25562
49227.4.12.0/26227.4.12.1 to 227.4.12.62227.4.12.6362
50227.4.12.64/26227.4.12.65 to 227.4.12.126227.4.12.12762
51227.4.12.128/26227.4.12.129 to 227.4.12.190227.4.12.19162
52227.4.12.192/26227.4.12.193 to 227.4.12.254227.4.12.25562
53227.4.13.0/26227.4.13.1 to 227.4.13.62227.4.13.6362
54227.4.13.64/26227.4.13.65 to 227.4.13.126227.4.13.12762
55227.4.13.128/26227.4.13.129 to 227.4.13.190227.4.13.19162
56227.4.13.192/26227.4.13.193 to 227.4.13.254227.4.13.25562
57227.4.14.0/26227.4.14.1 to 227.4.14.62227.4.14.6362
58227.4.14.64/26227.4.14.65 to 227.4.14.126227.4.14.12762
59227.4.14.128/26227.4.14.129 to 227.4.14.190227.4.14.19162
60227.4.14.192/26227.4.14.193 to 227.4.14.254227.4.14.25562
61227.4.15.0/26227.4.15.1 to 227.4.15.62227.4.15.6362
62227.4.15.64/26227.4.15.65 to 227.4.15.126227.4.15.12762
63227.4.15.128/26227.4.15.129 to 227.4.15.190227.4.15.19162
64227.4.15.192/26227.4.15.193 to 227.4.15.254227.4.15.25562
65227.4.16.0/26227.4.16.1 to 227.4.16.62227.4.16.6362
66227.4.16.64/26227.4.16.65 to 227.4.16.126227.4.16.12762
67227.4.16.128/26227.4.16.129 to 227.4.16.190227.4.16.19162
68227.4.16.192/26227.4.16.193 to 227.4.16.254227.4.16.25562
69227.4.17.0/26227.4.17.1 to 227.4.17.62227.4.17.6362
70227.4.17.64/26227.4.17.65 to 227.4.17.126227.4.17.12762
71227.4.17.128/26227.4.17.129 to 227.4.17.190227.4.17.19162
72227.4.17.192/26227.4.17.193 to 227.4.17.254227.4.17.25562
73227.4.18.0/26227.4.18.1 to 227.4.18.62227.4.18.6362
74227.4.18.64/26227.4.18.65 to 227.4.18.126227.4.18.12762
75227.4.18.128/26227.4.18.129 to 227.4.18.190227.4.18.19162
76227.4.18.192/26227.4.18.193 to 227.4.18.254227.4.18.25562
77227.4.19.0/26227.4.19.1 to 227.4.19.62227.4.19.6362
78227.4.19.64/26227.4.19.65 to 227.4.19.126227.4.19.12762
79227.4.19.128/26227.4.19.129 to 227.4.19.190227.4.19.19162
80227.4.19.192/26227.4.19.193 to 227.4.19.254227.4.19.25562
81227.4.20.0/26227.4.20.1 to 227.4.20.62227.4.20.6362
82227.4.20.64/26227.4.20.65 to 227.4.20.126227.4.20.12762
83227.4.20.128/26227.4.20.129 to 227.4.20.190227.4.20.19162
84227.4.20.192/26227.4.20.193 to 227.4.20.254227.4.20.25562
85227.4.21.0/26227.4.21.1 to 227.4.21.62227.4.21.6362
86227.4.21.64/26227.4.21.65 to 227.4.21.126227.4.21.12762
87227.4.21.128/26227.4.21.129 to 227.4.21.190227.4.21.19162
88227.4.21.192/26227.4.21.193 to 227.4.21.254227.4.21.25562
89227.4.22.0/26227.4.22.1 to 227.4.22.62227.4.22.6362
90227.4.22.64/26227.4.22.65 to 227.4.22.126227.4.22.12762
91227.4.22.128/26227.4.22.129 to 227.4.22.190227.4.22.19162
92227.4.22.192/26227.4.22.193 to 227.4.22.254227.4.22.25562
93227.4.23.0/26227.4.23.1 to 227.4.23.62227.4.23.6362
94227.4.23.64/26227.4.23.65 to 227.4.23.126227.4.23.12762
95227.4.23.128/26227.4.23.129 to 227.4.23.190227.4.23.19162
96227.4.23.192/26227.4.23.193 to 227.4.23.254227.4.23.25562
97227.4.24.0/26227.4.24.1 to 227.4.24.62227.4.24.6362
98227.4.24.64/26227.4.24.65 to 227.4.24.126227.4.24.12762
99227.4.24.128/26227.4.24.129 to 227.4.24.190227.4.24.19162
100227.4.24.192/26227.4.24.193 to 227.4.24.254227.4.24.25562
101227.4.25.0/26227.4.25.1 to 227.4.25.62227.4.25.6362
102227.4.25.64/26227.4.25.65 to 227.4.25.126227.4.25.12762
103227.4.25.128/26227.4.25.129 to 227.4.25.190227.4.25.19162
104227.4.25.192/26227.4.25.193 to 227.4.25.254227.4.25.25562
105227.4.26.0/26227.4.26.1 to 227.4.26.62227.4.26.6362
106227.4.26.64/26227.4.26.65 to 227.4.26.126227.4.26.12762
107227.4.26.128/26227.4.26.129 to 227.4.26.190227.4.26.19162
108227.4.26.192/26227.4.26.193 to 227.4.26.254227.4.26.25562
109227.4.27.0/26227.4.27.1 to 227.4.27.62227.4.27.6362
110227.4.27.64/26227.4.27.65 to 227.4.27.126227.4.27.12762
111227.4.27.128/26227.4.27.129 to 227.4.27.190227.4.27.19162
112227.4.27.192/26227.4.27.193 to 227.4.27.254227.4.27.25562
113227.4.28.0/26227.4.28.1 to 227.4.28.62227.4.28.6362
114227.4.28.64/26227.4.28.65 to 227.4.28.126227.4.28.12762
115227.4.28.128/26227.4.28.129 to 227.4.28.190227.4.28.19162
116227.4.28.192/26227.4.28.193 to 227.4.28.254227.4.28.25562
117227.4.29.0/26227.4.29.1 to 227.4.29.62227.4.29.6362
118227.4.29.64/26227.4.29.65 to 227.4.29.126227.4.29.12762
119227.4.29.128/26227.4.29.129 to 227.4.29.190227.4.29.19162
120227.4.29.192/26227.4.29.193 to 227.4.29.254227.4.29.25562
121227.4.30.0/26227.4.30.1 to 227.4.30.62227.4.30.6362
122227.4.30.64/26227.4.30.65 to 227.4.30.126227.4.30.12762
123227.4.30.128/26227.4.30.129 to 227.4.30.190227.4.30.19162
124227.4.30.192/26227.4.30.193 to 227.4.30.254227.4.30.25562
125227.4.31.0/26227.4.31.1 to 227.4.31.62227.4.31.6362
126227.4.31.64/26227.4.31.65 to 227.4.31.126227.4.31.12762
127227.4.31.128/26227.4.31.129 to 227.4.31.190227.4.31.19162
128227.4.31.192/26227.4.31.193 to 227.4.31.254227.4.31.25562
129227.4.32.0/26227.4.32.1 to 227.4.32.62227.4.32.6362
130227.4.32.64/26227.4.32.65 to 227.4.32.126227.4.32.12762
131227.4.32.128/26227.4.32.129 to 227.4.32.190227.4.32.19162
132227.4.32.192/26227.4.32.193 to 227.4.32.254227.4.32.25562
133227.4.33.0/26227.4.33.1 to 227.4.33.62227.4.33.6362
134227.4.33.64/26227.4.33.65 to 227.4.33.126227.4.33.12762
135227.4.33.128/26227.4.33.129 to 227.4.33.190227.4.33.19162
136227.4.33.192/26227.4.33.193 to 227.4.33.254227.4.33.25562
137227.4.34.0/26227.4.34.1 to 227.4.34.62227.4.34.6362
138227.4.34.64/26227.4.34.65 to 227.4.34.126227.4.34.12762
139227.4.34.128/26227.4.34.129 to 227.4.34.190227.4.34.19162
140227.4.34.192/26227.4.34.193 to 227.4.34.254227.4.34.25562
141227.4.35.0/26227.4.35.1 to 227.4.35.62227.4.35.6362
142227.4.35.64/26227.4.35.65 to 227.4.35.126227.4.35.12762
143227.4.35.128/26227.4.35.129 to 227.4.35.190227.4.35.19162
144227.4.35.192/26227.4.35.193 to 227.4.35.254227.4.35.25562
145227.4.36.0/26227.4.36.1 to 227.4.36.62227.4.36.6362
146227.4.36.64/26227.4.36.65 to 227.4.36.126227.4.36.12762
147227.4.36.128/26227.4.36.129 to 227.4.36.190227.4.36.19162
148227.4.36.192/26227.4.36.193 to 227.4.36.254227.4.36.25562
149227.4.37.0/26227.4.37.1 to 227.4.37.62227.4.37.6362
150227.4.37.64/26227.4.37.65 to 227.4.37.126227.4.37.12762
151227.4.37.128/26227.4.37.129 to 227.4.37.190227.4.37.19162
152227.4.37.192/26227.4.37.193 to 227.4.37.254227.4.37.25562
153227.4.38.0/26227.4.38.1 to 227.4.38.62227.4.38.6362
154227.4.38.64/26227.4.38.65 to 227.4.38.126227.4.38.12762
155227.4.38.128/26227.4.38.129 to 227.4.38.190227.4.38.19162
156227.4.38.192/26227.4.38.193 to 227.4.38.254227.4.38.25562
157227.4.39.0/26227.4.39.1 to 227.4.39.62227.4.39.6362
158227.4.39.64/26227.4.39.65 to 227.4.39.126227.4.39.12762
159227.4.39.128/26227.4.39.129 to 227.4.39.190227.4.39.19162
160227.4.39.192/26227.4.39.193 to 227.4.39.254227.4.39.25562
161227.4.40.0/26227.4.40.1 to 227.4.40.62227.4.40.6362
162227.4.40.64/26227.4.40.65 to 227.4.40.126227.4.40.12762
163227.4.40.128/26227.4.40.129 to 227.4.40.190227.4.40.19162
164227.4.40.192/26227.4.40.193 to 227.4.40.254227.4.40.25562
165227.4.41.0/26227.4.41.1 to 227.4.41.62227.4.41.6362
166227.4.41.64/26227.4.41.65 to 227.4.41.126227.4.41.12762
167227.4.41.128/26227.4.41.129 to 227.4.41.190227.4.41.19162
168227.4.41.192/26227.4.41.193 to 227.4.41.254227.4.41.25562
169227.4.42.0/26227.4.42.1 to 227.4.42.62227.4.42.6362
170227.4.42.64/26227.4.42.65 to 227.4.42.126227.4.42.12762
171227.4.42.128/26227.4.42.129 to 227.4.42.190227.4.42.19162
172227.4.42.192/26227.4.42.193 to 227.4.42.254227.4.42.25562
173227.4.43.0/26227.4.43.1 to 227.4.43.62227.4.43.6362
174227.4.43.64/26227.4.43.65 to 227.4.43.126227.4.43.12762
175227.4.43.128/26227.4.43.129 to 227.4.43.190227.4.43.19162
176227.4.43.192/26227.4.43.193 to 227.4.43.254227.4.43.25562
177227.4.44.0/26227.4.44.1 to 227.4.44.62227.4.44.6362
178227.4.44.64/26227.4.44.65 to 227.4.44.126227.4.44.12762
179227.4.44.128/26227.4.44.129 to 227.4.44.190227.4.44.19162
180227.4.44.192/26227.4.44.193 to 227.4.44.254227.4.44.25562
181227.4.45.0/26227.4.45.1 to 227.4.45.62227.4.45.6362
182227.4.45.64/26227.4.45.65 to 227.4.45.126227.4.45.12762
183227.4.45.128/26227.4.45.129 to 227.4.45.190227.4.45.19162
184227.4.45.192/26227.4.45.193 to 227.4.45.254227.4.45.25562
185227.4.46.0/26227.4.46.1 to 227.4.46.62227.4.46.6362
186227.4.46.64/26227.4.46.65 to 227.4.46.126227.4.46.12762
187227.4.46.128/26227.4.46.129 to 227.4.46.190227.4.46.19162
188227.4.46.192/26227.4.46.193 to 227.4.46.254227.4.46.25562
189227.4.47.0/26227.4.47.1 to 227.4.47.62227.4.47.6362
190227.4.47.64/26227.4.47.65 to 227.4.47.126227.4.47.12762
191227.4.47.128/26227.4.47.129 to 227.4.47.190227.4.47.19162
192227.4.47.192/26227.4.47.193 to 227.4.47.254227.4.47.25562
193227.4.48.0/26227.4.48.1 to 227.4.48.62227.4.48.6362
194227.4.48.64/26227.4.48.65 to 227.4.48.126227.4.48.12762
195227.4.48.128/26227.4.48.129 to 227.4.48.190227.4.48.19162
196227.4.48.192/26227.4.48.193 to 227.4.48.254227.4.48.25562
197227.4.49.0/26227.4.49.1 to 227.4.49.62227.4.49.6362
198227.4.49.64/26227.4.49.65 to 227.4.49.126227.4.49.12762
199227.4.49.128/26227.4.49.129 to 227.4.49.190227.4.49.19162
200227.4.49.192/26227.4.49.193 to 227.4.49.254227.4.49.25562
201227.4.50.0/26227.4.50.1 to 227.4.50.62227.4.50.6362
202227.4.50.64/26227.4.50.65 to 227.4.50.126227.4.50.12762
203227.4.50.128/26227.4.50.129 to 227.4.50.190227.4.50.19162
204227.4.50.192/26227.4.50.193 to 227.4.50.254227.4.50.25562
205227.4.51.0/26227.4.51.1 to 227.4.51.62227.4.51.6362
206227.4.51.64/26227.4.51.65 to 227.4.51.126227.4.51.12762
207227.4.51.128/26227.4.51.129 to 227.4.51.190227.4.51.19162
208227.4.51.192/26227.4.51.193 to 227.4.51.254227.4.51.25562
209227.4.52.0/26227.4.52.1 to 227.4.52.62227.4.52.6362
210227.4.52.64/26227.4.52.65 to 227.4.52.126227.4.52.12762
211227.4.52.128/26227.4.52.129 to 227.4.52.190227.4.52.19162
212227.4.52.192/26227.4.52.193 to 227.4.52.254227.4.52.25562
213227.4.53.0/26227.4.53.1 to 227.4.53.62227.4.53.6362
214227.4.53.64/26227.4.53.65 to 227.4.53.126227.4.53.12762
215227.4.53.128/26227.4.53.129 to 227.4.53.190227.4.53.19162
216227.4.53.192/26227.4.53.193 to 227.4.53.254227.4.53.25562
217227.4.54.0/26227.4.54.1 to 227.4.54.62227.4.54.6362
218227.4.54.64/26227.4.54.65 to 227.4.54.126227.4.54.12762
219227.4.54.128/26227.4.54.129 to 227.4.54.190227.4.54.19162
220227.4.54.192/26227.4.54.193 to 227.4.54.254227.4.54.25562
221227.4.55.0/26227.4.55.1 to 227.4.55.62227.4.55.6362
222227.4.55.64/26227.4.55.65 to 227.4.55.126227.4.55.12762
223227.4.55.128/26227.4.55.129 to 227.4.55.190227.4.55.19162
224227.4.55.192/26227.4.55.193 to 227.4.55.254227.4.55.25562
225227.4.56.0/26227.4.56.1 to 227.4.56.62227.4.56.6362
226227.4.56.64/26227.4.56.65 to 227.4.56.126227.4.56.12762
227227.4.56.128/26227.4.56.129 to 227.4.56.190227.4.56.19162
228227.4.56.192/26227.4.56.193 to 227.4.56.254227.4.56.25562
229227.4.57.0/26227.4.57.1 to 227.4.57.62227.4.57.6362
230227.4.57.64/26227.4.57.65 to 227.4.57.126227.4.57.12762
231227.4.57.128/26227.4.57.129 to 227.4.57.190227.4.57.19162
232227.4.57.192/26227.4.57.193 to 227.4.57.254227.4.57.25562
233227.4.58.0/26227.4.58.1 to 227.4.58.62227.4.58.6362
234227.4.58.64/26227.4.58.65 to 227.4.58.126227.4.58.12762
235227.4.58.128/26227.4.58.129 to 227.4.58.190227.4.58.19162
236227.4.58.192/26227.4.58.193 to 227.4.58.254227.4.58.25562
237227.4.59.0/26227.4.59.1 to 227.4.59.62227.4.59.6362
238227.4.59.64/26227.4.59.65 to 227.4.59.126227.4.59.12762
239227.4.59.128/26227.4.59.129 to 227.4.59.190227.4.59.19162
240227.4.59.192/26227.4.59.193 to 227.4.59.254227.4.59.25562
241227.4.60.0/26227.4.60.1 to 227.4.60.62227.4.60.6362
242227.4.60.64/26227.4.60.65 to 227.4.60.126227.4.60.12762
243227.4.60.128/26227.4.60.129 to 227.4.60.190227.4.60.19162
244227.4.60.192/26227.4.60.193 to 227.4.60.254227.4.60.25562
245227.4.61.0/26227.4.61.1 to 227.4.61.62227.4.61.6362
246227.4.61.64/26227.4.61.65 to 227.4.61.126227.4.61.12762
247227.4.61.128/26227.4.61.129 to 227.4.61.190227.4.61.19162
248227.4.61.192/26227.4.61.193 to 227.4.61.254227.4.61.25562
249227.4.62.0/26227.4.62.1 to 227.4.62.62227.4.62.6362
250227.4.62.64/26227.4.62.65 to 227.4.62.126227.4.62.12762
251227.4.62.128/26227.4.62.129 to 227.4.62.190227.4.62.19162
252227.4.62.192/26227.4.62.193 to 227.4.62.254227.4.62.25562
253227.4.63.0/26227.4.63.1 to 227.4.63.62227.4.63.6362
254227.4.63.64/26227.4.63.65 to 227.4.63.126227.4.63.12762
255227.4.63.128/26227.4.63.129 to 227.4.63.190227.4.63.19162
256227.4.63.192/26227.4.63.193 to 227.4.63.254227.4.63.25562

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.