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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.

Network110.9.0.0/19
Usable hosts8,190
Subnet mask255.255.224.0
Addresses8,192
Network address
110.9.0.0
Broadcast address
110.9.31.255
First usable
110.9.0.1
Last usable
110.9.31.254
Usable hosts
8,190 (8,192 less the network and broadcast addresses)
Subnet mask
255.255.224.0
Wildcard mask
0.0.31.255 (Cisco ACLs, OSPF)
Prefix length
/19
Type
Public public
Old class
A (default /8)
As numbers
Hex 6E090000 · Integer 1846083584 to 1846091775
Reverse DNS zones
0.9.110.in-addr.arpa
1.9.110.in-addr.arpa
2.9.110.in-addr.arpa
3.9.110.in-addr.arpa
4.9.110.in-addr.arpa
5.9.110.in-addr.arpa
6.9.110.in-addr.arpa
7.9.110.in-addr.arpa
8.9.110.in-addr.arpa
9.9.110.in-addr.arpa
10.9.110.in-addr.arpa
11.9.110.in-addr.arpa
12.9.110.in-addr.arpa
13.9.110.in-addr.arpa
14.9.110.in-addr.arpa
15.9.110.in-addr.arpa
and 16 more
/19 is not on a 8-bit boundary, so it takes 32 /24 zones.
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address01101110.00001001.00000000.00000000110.9.0.0
Subnet mask11111111.11111111.11100000.00000000255.255.224.0
Network01101110.00001001.00000000.00000000110.9.0.0
Broadcast01101110.00001001.00011111.11111111110.9.31.255
Split into smaller subnets/29
/20 (2)/21 (4)/22 (8)/23 (16)/24 (32)/25 (64)/26 (128)/27 (256)/28 (512)/29 (1,024)/30 (2,048)/31 (4,096)

110.9.0.0/19 makes 1,024 subnets of /29; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
1110.9.0.0/29110.9.0.1 to 110.9.0.6110.9.0.76
2110.9.0.8/29110.9.0.9 to 110.9.0.14110.9.0.156
3110.9.0.16/29110.9.0.17 to 110.9.0.22110.9.0.236
4110.9.0.24/29110.9.0.25 to 110.9.0.30110.9.0.316
5110.9.0.32/29110.9.0.33 to 110.9.0.38110.9.0.396
6110.9.0.40/29110.9.0.41 to 110.9.0.46110.9.0.476
7110.9.0.48/29110.9.0.49 to 110.9.0.54110.9.0.556
8110.9.0.56/29110.9.0.57 to 110.9.0.62110.9.0.636
9110.9.0.64/29110.9.0.65 to 110.9.0.70110.9.0.716
10110.9.0.72/29110.9.0.73 to 110.9.0.78110.9.0.796
11110.9.0.80/29110.9.0.81 to 110.9.0.86110.9.0.876
12110.9.0.88/29110.9.0.89 to 110.9.0.94110.9.0.956
13110.9.0.96/29110.9.0.97 to 110.9.0.102110.9.0.1036
14110.9.0.104/29110.9.0.105 to 110.9.0.110110.9.0.1116
15110.9.0.112/29110.9.0.113 to 110.9.0.118110.9.0.1196
16110.9.0.120/29110.9.0.121 to 110.9.0.126110.9.0.1276
17110.9.0.128/29110.9.0.129 to 110.9.0.134110.9.0.1356
18110.9.0.136/29110.9.0.137 to 110.9.0.142110.9.0.1436
19110.9.0.144/29110.9.0.145 to 110.9.0.150110.9.0.1516
20110.9.0.152/29110.9.0.153 to 110.9.0.158110.9.0.1596
21110.9.0.160/29110.9.0.161 to 110.9.0.166110.9.0.1676
22110.9.0.168/29110.9.0.169 to 110.9.0.174110.9.0.1756
23110.9.0.176/29110.9.0.177 to 110.9.0.182110.9.0.1836
24110.9.0.184/29110.9.0.185 to 110.9.0.190110.9.0.1916
25110.9.0.192/29110.9.0.193 to 110.9.0.198110.9.0.1996
26110.9.0.200/29110.9.0.201 to 110.9.0.206110.9.0.2076
27110.9.0.208/29110.9.0.209 to 110.9.0.214110.9.0.2156
28110.9.0.216/29110.9.0.217 to 110.9.0.222110.9.0.2236
29110.9.0.224/29110.9.0.225 to 110.9.0.230110.9.0.2316
30110.9.0.232/29110.9.0.233 to 110.9.0.238110.9.0.2396
31110.9.0.240/29110.9.0.241 to 110.9.0.246110.9.0.2476
32110.9.0.248/29110.9.0.249 to 110.9.0.254110.9.0.2556
33110.9.1.0/29110.9.1.1 to 110.9.1.6110.9.1.76
34110.9.1.8/29110.9.1.9 to 110.9.1.14110.9.1.156
35110.9.1.16/29110.9.1.17 to 110.9.1.22110.9.1.236
36110.9.1.24/29110.9.1.25 to 110.9.1.30110.9.1.316
37110.9.1.32/29110.9.1.33 to 110.9.1.38110.9.1.396
38110.9.1.40/29110.9.1.41 to 110.9.1.46110.9.1.476
39110.9.1.48/29110.9.1.49 to 110.9.1.54110.9.1.556
40110.9.1.56/29110.9.1.57 to 110.9.1.62110.9.1.636
41110.9.1.64/29110.9.1.65 to 110.9.1.70110.9.1.716
42110.9.1.72/29110.9.1.73 to 110.9.1.78110.9.1.796
43110.9.1.80/29110.9.1.81 to 110.9.1.86110.9.1.876
44110.9.1.88/29110.9.1.89 to 110.9.1.94110.9.1.956
45110.9.1.96/29110.9.1.97 to 110.9.1.102110.9.1.1036
46110.9.1.104/29110.9.1.105 to 110.9.1.110110.9.1.1116
47110.9.1.112/29110.9.1.113 to 110.9.1.118110.9.1.1196
48110.9.1.120/29110.9.1.121 to 110.9.1.126110.9.1.1276
49110.9.1.128/29110.9.1.129 to 110.9.1.134110.9.1.1356
50110.9.1.136/29110.9.1.137 to 110.9.1.142110.9.1.1436
51110.9.1.144/29110.9.1.145 to 110.9.1.150110.9.1.1516
52110.9.1.152/29110.9.1.153 to 110.9.1.158110.9.1.1596
53110.9.1.160/29110.9.1.161 to 110.9.1.166110.9.1.1676
54110.9.1.168/29110.9.1.169 to 110.9.1.174110.9.1.1756
55110.9.1.176/29110.9.1.177 to 110.9.1.182110.9.1.1836
56110.9.1.184/29110.9.1.185 to 110.9.1.190110.9.1.1916
57110.9.1.192/29110.9.1.193 to 110.9.1.198110.9.1.1996
58110.9.1.200/29110.9.1.201 to 110.9.1.206110.9.1.2076
59110.9.1.208/29110.9.1.209 to 110.9.1.214110.9.1.2156
60110.9.1.216/29110.9.1.217 to 110.9.1.222110.9.1.2236
61110.9.1.224/29110.9.1.225 to 110.9.1.230110.9.1.2316
62110.9.1.232/29110.9.1.233 to 110.9.1.238110.9.1.2396
63110.9.1.240/29110.9.1.241 to 110.9.1.246110.9.1.2476
64110.9.1.248/29110.9.1.249 to 110.9.1.254110.9.1.2556
65110.9.2.0/29110.9.2.1 to 110.9.2.6110.9.2.76
66110.9.2.8/29110.9.2.9 to 110.9.2.14110.9.2.156
67110.9.2.16/29110.9.2.17 to 110.9.2.22110.9.2.236
68110.9.2.24/29110.9.2.25 to 110.9.2.30110.9.2.316
69110.9.2.32/29110.9.2.33 to 110.9.2.38110.9.2.396
70110.9.2.40/29110.9.2.41 to 110.9.2.46110.9.2.476
71110.9.2.48/29110.9.2.49 to 110.9.2.54110.9.2.556
72110.9.2.56/29110.9.2.57 to 110.9.2.62110.9.2.636
73110.9.2.64/29110.9.2.65 to 110.9.2.70110.9.2.716
74110.9.2.72/29110.9.2.73 to 110.9.2.78110.9.2.796
75110.9.2.80/29110.9.2.81 to 110.9.2.86110.9.2.876
76110.9.2.88/29110.9.2.89 to 110.9.2.94110.9.2.956
77110.9.2.96/29110.9.2.97 to 110.9.2.102110.9.2.1036
78110.9.2.104/29110.9.2.105 to 110.9.2.110110.9.2.1116
79110.9.2.112/29110.9.2.113 to 110.9.2.118110.9.2.1196
80110.9.2.120/29110.9.2.121 to 110.9.2.126110.9.2.1276
81110.9.2.128/29110.9.2.129 to 110.9.2.134110.9.2.1356
82110.9.2.136/29110.9.2.137 to 110.9.2.142110.9.2.1436
83110.9.2.144/29110.9.2.145 to 110.9.2.150110.9.2.1516
84110.9.2.152/29110.9.2.153 to 110.9.2.158110.9.2.1596
85110.9.2.160/29110.9.2.161 to 110.9.2.166110.9.2.1676
86110.9.2.168/29110.9.2.169 to 110.9.2.174110.9.2.1756
87110.9.2.176/29110.9.2.177 to 110.9.2.182110.9.2.1836
88110.9.2.184/29110.9.2.185 to 110.9.2.190110.9.2.1916
89110.9.2.192/29110.9.2.193 to 110.9.2.198110.9.2.1996
90110.9.2.200/29110.9.2.201 to 110.9.2.206110.9.2.2076
91110.9.2.208/29110.9.2.209 to 110.9.2.214110.9.2.2156
92110.9.2.216/29110.9.2.217 to 110.9.2.222110.9.2.2236
93110.9.2.224/29110.9.2.225 to 110.9.2.230110.9.2.2316
94110.9.2.232/29110.9.2.233 to 110.9.2.238110.9.2.2396
95110.9.2.240/29110.9.2.241 to 110.9.2.246110.9.2.2476
96110.9.2.248/29110.9.2.249 to 110.9.2.254110.9.2.2556
97110.9.3.0/29110.9.3.1 to 110.9.3.6110.9.3.76
98110.9.3.8/29110.9.3.9 to 110.9.3.14110.9.3.156
99110.9.3.16/29110.9.3.17 to 110.9.3.22110.9.3.236
100110.9.3.24/29110.9.3.25 to 110.9.3.30110.9.3.316
101110.9.3.32/29110.9.3.33 to 110.9.3.38110.9.3.396
102110.9.3.40/29110.9.3.41 to 110.9.3.46110.9.3.476
103110.9.3.48/29110.9.3.49 to 110.9.3.54110.9.3.556
104110.9.3.56/29110.9.3.57 to 110.9.3.62110.9.3.636
105110.9.3.64/29110.9.3.65 to 110.9.3.70110.9.3.716
106110.9.3.72/29110.9.3.73 to 110.9.3.78110.9.3.796
107110.9.3.80/29110.9.3.81 to 110.9.3.86110.9.3.876
108110.9.3.88/29110.9.3.89 to 110.9.3.94110.9.3.956
109110.9.3.96/29110.9.3.97 to 110.9.3.102110.9.3.1036
110110.9.3.104/29110.9.3.105 to 110.9.3.110110.9.3.1116
111110.9.3.112/29110.9.3.113 to 110.9.3.118110.9.3.1196
112110.9.3.120/29110.9.3.121 to 110.9.3.126110.9.3.1276
113110.9.3.128/29110.9.3.129 to 110.9.3.134110.9.3.1356
114110.9.3.136/29110.9.3.137 to 110.9.3.142110.9.3.1436
115110.9.3.144/29110.9.3.145 to 110.9.3.150110.9.3.1516
116110.9.3.152/29110.9.3.153 to 110.9.3.158110.9.3.1596
117110.9.3.160/29110.9.3.161 to 110.9.3.166110.9.3.1676
118110.9.3.168/29110.9.3.169 to 110.9.3.174110.9.3.1756
119110.9.3.176/29110.9.3.177 to 110.9.3.182110.9.3.1836
120110.9.3.184/29110.9.3.185 to 110.9.3.190110.9.3.1916
121110.9.3.192/29110.9.3.193 to 110.9.3.198110.9.3.1996
122110.9.3.200/29110.9.3.201 to 110.9.3.206110.9.3.2076
123110.9.3.208/29110.9.3.209 to 110.9.3.214110.9.3.2156
124110.9.3.216/29110.9.3.217 to 110.9.3.222110.9.3.2236
125110.9.3.224/29110.9.3.225 to 110.9.3.230110.9.3.2316
126110.9.3.232/29110.9.3.233 to 110.9.3.238110.9.3.2396
127110.9.3.240/29110.9.3.241 to 110.9.3.246110.9.3.2476
128110.9.3.248/29110.9.3.249 to 110.9.3.254110.9.3.2556
129110.9.4.0/29110.9.4.1 to 110.9.4.6110.9.4.76
130110.9.4.8/29110.9.4.9 to 110.9.4.14110.9.4.156
131110.9.4.16/29110.9.4.17 to 110.9.4.22110.9.4.236
132110.9.4.24/29110.9.4.25 to 110.9.4.30110.9.4.316
133110.9.4.32/29110.9.4.33 to 110.9.4.38110.9.4.396
134110.9.4.40/29110.9.4.41 to 110.9.4.46110.9.4.476
135110.9.4.48/29110.9.4.49 to 110.9.4.54110.9.4.556
136110.9.4.56/29110.9.4.57 to 110.9.4.62110.9.4.636
137110.9.4.64/29110.9.4.65 to 110.9.4.70110.9.4.716
138110.9.4.72/29110.9.4.73 to 110.9.4.78110.9.4.796
139110.9.4.80/29110.9.4.81 to 110.9.4.86110.9.4.876
140110.9.4.88/29110.9.4.89 to 110.9.4.94110.9.4.956
141110.9.4.96/29110.9.4.97 to 110.9.4.102110.9.4.1036
142110.9.4.104/29110.9.4.105 to 110.9.4.110110.9.4.1116
143110.9.4.112/29110.9.4.113 to 110.9.4.118110.9.4.1196
144110.9.4.120/29110.9.4.121 to 110.9.4.126110.9.4.1276
145110.9.4.128/29110.9.4.129 to 110.9.4.134110.9.4.1356
146110.9.4.136/29110.9.4.137 to 110.9.4.142110.9.4.1436
147110.9.4.144/29110.9.4.145 to 110.9.4.150110.9.4.1516
148110.9.4.152/29110.9.4.153 to 110.9.4.158110.9.4.1596
149110.9.4.160/29110.9.4.161 to 110.9.4.166110.9.4.1676
150110.9.4.168/29110.9.4.169 to 110.9.4.174110.9.4.1756
151110.9.4.176/29110.9.4.177 to 110.9.4.182110.9.4.1836
152110.9.4.184/29110.9.4.185 to 110.9.4.190110.9.4.1916
153110.9.4.192/29110.9.4.193 to 110.9.4.198110.9.4.1996
154110.9.4.200/29110.9.4.201 to 110.9.4.206110.9.4.2076
155110.9.4.208/29110.9.4.209 to 110.9.4.214110.9.4.2156
156110.9.4.216/29110.9.4.217 to 110.9.4.222110.9.4.2236
157110.9.4.224/29110.9.4.225 to 110.9.4.230110.9.4.2316
158110.9.4.232/29110.9.4.233 to 110.9.4.238110.9.4.2396
159110.9.4.240/29110.9.4.241 to 110.9.4.246110.9.4.2476
160110.9.4.248/29110.9.4.249 to 110.9.4.254110.9.4.2556
161110.9.5.0/29110.9.5.1 to 110.9.5.6110.9.5.76
162110.9.5.8/29110.9.5.9 to 110.9.5.14110.9.5.156
163110.9.5.16/29110.9.5.17 to 110.9.5.22110.9.5.236
164110.9.5.24/29110.9.5.25 to 110.9.5.30110.9.5.316
165110.9.5.32/29110.9.5.33 to 110.9.5.38110.9.5.396
166110.9.5.40/29110.9.5.41 to 110.9.5.46110.9.5.476
167110.9.5.48/29110.9.5.49 to 110.9.5.54110.9.5.556
168110.9.5.56/29110.9.5.57 to 110.9.5.62110.9.5.636
169110.9.5.64/29110.9.5.65 to 110.9.5.70110.9.5.716
170110.9.5.72/29110.9.5.73 to 110.9.5.78110.9.5.796
171110.9.5.80/29110.9.5.81 to 110.9.5.86110.9.5.876
172110.9.5.88/29110.9.5.89 to 110.9.5.94110.9.5.956
173110.9.5.96/29110.9.5.97 to 110.9.5.102110.9.5.1036
174110.9.5.104/29110.9.5.105 to 110.9.5.110110.9.5.1116
175110.9.5.112/29110.9.5.113 to 110.9.5.118110.9.5.1196
176110.9.5.120/29110.9.5.121 to 110.9.5.126110.9.5.1276
177110.9.5.128/29110.9.5.129 to 110.9.5.134110.9.5.1356
178110.9.5.136/29110.9.5.137 to 110.9.5.142110.9.5.1436
179110.9.5.144/29110.9.5.145 to 110.9.5.150110.9.5.1516
180110.9.5.152/29110.9.5.153 to 110.9.5.158110.9.5.1596
181110.9.5.160/29110.9.5.161 to 110.9.5.166110.9.5.1676
182110.9.5.168/29110.9.5.169 to 110.9.5.174110.9.5.1756
183110.9.5.176/29110.9.5.177 to 110.9.5.182110.9.5.1836
184110.9.5.184/29110.9.5.185 to 110.9.5.190110.9.5.1916
185110.9.5.192/29110.9.5.193 to 110.9.5.198110.9.5.1996
186110.9.5.200/29110.9.5.201 to 110.9.5.206110.9.5.2076
187110.9.5.208/29110.9.5.209 to 110.9.5.214110.9.5.2156
188110.9.5.216/29110.9.5.217 to 110.9.5.222110.9.5.2236
189110.9.5.224/29110.9.5.225 to 110.9.5.230110.9.5.2316
190110.9.5.232/29110.9.5.233 to 110.9.5.238110.9.5.2396
191110.9.5.240/29110.9.5.241 to 110.9.5.246110.9.5.2476
192110.9.5.248/29110.9.5.249 to 110.9.5.254110.9.5.2556
193110.9.6.0/29110.9.6.1 to 110.9.6.6110.9.6.76
194110.9.6.8/29110.9.6.9 to 110.9.6.14110.9.6.156
195110.9.6.16/29110.9.6.17 to 110.9.6.22110.9.6.236
196110.9.6.24/29110.9.6.25 to 110.9.6.30110.9.6.316
197110.9.6.32/29110.9.6.33 to 110.9.6.38110.9.6.396
198110.9.6.40/29110.9.6.41 to 110.9.6.46110.9.6.476
199110.9.6.48/29110.9.6.49 to 110.9.6.54110.9.6.556
200110.9.6.56/29110.9.6.57 to 110.9.6.62110.9.6.636
201110.9.6.64/29110.9.6.65 to 110.9.6.70110.9.6.716
202110.9.6.72/29110.9.6.73 to 110.9.6.78110.9.6.796
203110.9.6.80/29110.9.6.81 to 110.9.6.86110.9.6.876
204110.9.6.88/29110.9.6.89 to 110.9.6.94110.9.6.956
205110.9.6.96/29110.9.6.97 to 110.9.6.102110.9.6.1036
206110.9.6.104/29110.9.6.105 to 110.9.6.110110.9.6.1116
207110.9.6.112/29110.9.6.113 to 110.9.6.118110.9.6.1196
208110.9.6.120/29110.9.6.121 to 110.9.6.126110.9.6.1276
209110.9.6.128/29110.9.6.129 to 110.9.6.134110.9.6.1356
210110.9.6.136/29110.9.6.137 to 110.9.6.142110.9.6.1436
211110.9.6.144/29110.9.6.145 to 110.9.6.150110.9.6.1516
212110.9.6.152/29110.9.6.153 to 110.9.6.158110.9.6.1596
213110.9.6.160/29110.9.6.161 to 110.9.6.166110.9.6.1676
214110.9.6.168/29110.9.6.169 to 110.9.6.174110.9.6.1756
215110.9.6.176/29110.9.6.177 to 110.9.6.182110.9.6.1836
216110.9.6.184/29110.9.6.185 to 110.9.6.190110.9.6.1916
217110.9.6.192/29110.9.6.193 to 110.9.6.198110.9.6.1996
218110.9.6.200/29110.9.6.201 to 110.9.6.206110.9.6.2076
219110.9.6.208/29110.9.6.209 to 110.9.6.214110.9.6.2156
220110.9.6.216/29110.9.6.217 to 110.9.6.222110.9.6.2236
221110.9.6.224/29110.9.6.225 to 110.9.6.230110.9.6.2316
222110.9.6.232/29110.9.6.233 to 110.9.6.238110.9.6.2396
223110.9.6.240/29110.9.6.241 to 110.9.6.246110.9.6.2476
224110.9.6.248/29110.9.6.249 to 110.9.6.254110.9.6.2556
225110.9.7.0/29110.9.7.1 to 110.9.7.6110.9.7.76
226110.9.7.8/29110.9.7.9 to 110.9.7.14110.9.7.156
227110.9.7.16/29110.9.7.17 to 110.9.7.22110.9.7.236
228110.9.7.24/29110.9.7.25 to 110.9.7.30110.9.7.316
229110.9.7.32/29110.9.7.33 to 110.9.7.38110.9.7.396
230110.9.7.40/29110.9.7.41 to 110.9.7.46110.9.7.476
231110.9.7.48/29110.9.7.49 to 110.9.7.54110.9.7.556
232110.9.7.56/29110.9.7.57 to 110.9.7.62110.9.7.636
233110.9.7.64/29110.9.7.65 to 110.9.7.70110.9.7.716
234110.9.7.72/29110.9.7.73 to 110.9.7.78110.9.7.796
235110.9.7.80/29110.9.7.81 to 110.9.7.86110.9.7.876
236110.9.7.88/29110.9.7.89 to 110.9.7.94110.9.7.956
237110.9.7.96/29110.9.7.97 to 110.9.7.102110.9.7.1036
238110.9.7.104/29110.9.7.105 to 110.9.7.110110.9.7.1116
239110.9.7.112/29110.9.7.113 to 110.9.7.118110.9.7.1196
240110.9.7.120/29110.9.7.121 to 110.9.7.126110.9.7.1276
241110.9.7.128/29110.9.7.129 to 110.9.7.134110.9.7.1356
242110.9.7.136/29110.9.7.137 to 110.9.7.142110.9.7.1436
243110.9.7.144/29110.9.7.145 to 110.9.7.150110.9.7.1516
244110.9.7.152/29110.9.7.153 to 110.9.7.158110.9.7.1596
245110.9.7.160/29110.9.7.161 to 110.9.7.166110.9.7.1676
246110.9.7.168/29110.9.7.169 to 110.9.7.174110.9.7.1756
247110.9.7.176/29110.9.7.177 to 110.9.7.182110.9.7.1836
248110.9.7.184/29110.9.7.185 to 110.9.7.190110.9.7.1916
249110.9.7.192/29110.9.7.193 to 110.9.7.198110.9.7.1996
250110.9.7.200/29110.9.7.201 to 110.9.7.206110.9.7.2076
251110.9.7.208/29110.9.7.209 to 110.9.7.214110.9.7.2156
252110.9.7.216/29110.9.7.217 to 110.9.7.222110.9.7.2236
253110.9.7.224/29110.9.7.225 to 110.9.7.230110.9.7.2316
254110.9.7.232/29110.9.7.233 to 110.9.7.238110.9.7.2396
255110.9.7.240/29110.9.7.241 to 110.9.7.246110.9.7.2476
256110.9.7.248/29110.9.7.249 to 110.9.7.254110.9.7.2556

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.