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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.

Network154.26.0.0/19
Usable hosts8,190
Subnet mask255.255.224.0
Addresses8,192
Network address
154.26.0.0
Broadcast address
154.26.31.255
First usable
154.26.0.1
Last usable
154.26.31.254
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
B (default /16)
As numbers
Hex 9A1A0000 · Integer 2585395200 to 2585403391
Reverse DNS zones
0.26.154.in-addr.arpa
1.26.154.in-addr.arpa
2.26.154.in-addr.arpa
3.26.154.in-addr.arpa
4.26.154.in-addr.arpa
5.26.154.in-addr.arpa
6.26.154.in-addr.arpa
7.26.154.in-addr.arpa
8.26.154.in-addr.arpa
9.26.154.in-addr.arpa
10.26.154.in-addr.arpa
11.26.154.in-addr.arpa
12.26.154.in-addr.arpa
13.26.154.in-addr.arpa
14.26.154.in-addr.arpa
15.26.154.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
Address10011010.00011010.00000000.00000000154.26.0.0
Subnet mask11111111.11111111.11100000.00000000255.255.224.0
Network10011010.00011010.00000000.00000000154.26.0.0
Broadcast10011010.00011010.00011111.11111111154.26.31.255
Split into smaller subnets/30
/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)

154.26.0.0/19 makes 2,048 subnets of /30; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
1154.26.0.0/30154.26.0.1 to 154.26.0.2154.26.0.32
2154.26.0.4/30154.26.0.5 to 154.26.0.6154.26.0.72
3154.26.0.8/30154.26.0.9 to 154.26.0.10154.26.0.112
4154.26.0.12/30154.26.0.13 to 154.26.0.14154.26.0.152
5154.26.0.16/30154.26.0.17 to 154.26.0.18154.26.0.192
6154.26.0.20/30154.26.0.21 to 154.26.0.22154.26.0.232
7154.26.0.24/30154.26.0.25 to 154.26.0.26154.26.0.272
8154.26.0.28/30154.26.0.29 to 154.26.0.30154.26.0.312
9154.26.0.32/30154.26.0.33 to 154.26.0.34154.26.0.352
10154.26.0.36/30154.26.0.37 to 154.26.0.38154.26.0.392
11154.26.0.40/30154.26.0.41 to 154.26.0.42154.26.0.432
12154.26.0.44/30154.26.0.45 to 154.26.0.46154.26.0.472
13154.26.0.48/30154.26.0.49 to 154.26.0.50154.26.0.512
14154.26.0.52/30154.26.0.53 to 154.26.0.54154.26.0.552
15154.26.0.56/30154.26.0.57 to 154.26.0.58154.26.0.592
16154.26.0.60/30154.26.0.61 to 154.26.0.62154.26.0.632
17154.26.0.64/30154.26.0.65 to 154.26.0.66154.26.0.672
18154.26.0.68/30154.26.0.69 to 154.26.0.70154.26.0.712
19154.26.0.72/30154.26.0.73 to 154.26.0.74154.26.0.752
20154.26.0.76/30154.26.0.77 to 154.26.0.78154.26.0.792
21154.26.0.80/30154.26.0.81 to 154.26.0.82154.26.0.832
22154.26.0.84/30154.26.0.85 to 154.26.0.86154.26.0.872
23154.26.0.88/30154.26.0.89 to 154.26.0.90154.26.0.912
24154.26.0.92/30154.26.0.93 to 154.26.0.94154.26.0.952
25154.26.0.96/30154.26.0.97 to 154.26.0.98154.26.0.992
26154.26.0.100/30154.26.0.101 to 154.26.0.102154.26.0.1032
27154.26.0.104/30154.26.0.105 to 154.26.0.106154.26.0.1072
28154.26.0.108/30154.26.0.109 to 154.26.0.110154.26.0.1112
29154.26.0.112/30154.26.0.113 to 154.26.0.114154.26.0.1152
30154.26.0.116/30154.26.0.117 to 154.26.0.118154.26.0.1192
31154.26.0.120/30154.26.0.121 to 154.26.0.122154.26.0.1232
32154.26.0.124/30154.26.0.125 to 154.26.0.126154.26.0.1272
33154.26.0.128/30154.26.0.129 to 154.26.0.130154.26.0.1312
34154.26.0.132/30154.26.0.133 to 154.26.0.134154.26.0.1352
35154.26.0.136/30154.26.0.137 to 154.26.0.138154.26.0.1392
36154.26.0.140/30154.26.0.141 to 154.26.0.142154.26.0.1432
37154.26.0.144/30154.26.0.145 to 154.26.0.146154.26.0.1472
38154.26.0.148/30154.26.0.149 to 154.26.0.150154.26.0.1512
39154.26.0.152/30154.26.0.153 to 154.26.0.154154.26.0.1552
40154.26.0.156/30154.26.0.157 to 154.26.0.158154.26.0.1592
41154.26.0.160/30154.26.0.161 to 154.26.0.162154.26.0.1632
42154.26.0.164/30154.26.0.165 to 154.26.0.166154.26.0.1672
43154.26.0.168/30154.26.0.169 to 154.26.0.170154.26.0.1712
44154.26.0.172/30154.26.0.173 to 154.26.0.174154.26.0.1752
45154.26.0.176/30154.26.0.177 to 154.26.0.178154.26.0.1792
46154.26.0.180/30154.26.0.181 to 154.26.0.182154.26.0.1832
47154.26.0.184/30154.26.0.185 to 154.26.0.186154.26.0.1872
48154.26.0.188/30154.26.0.189 to 154.26.0.190154.26.0.1912
49154.26.0.192/30154.26.0.193 to 154.26.0.194154.26.0.1952
50154.26.0.196/30154.26.0.197 to 154.26.0.198154.26.0.1992
51154.26.0.200/30154.26.0.201 to 154.26.0.202154.26.0.2032
52154.26.0.204/30154.26.0.205 to 154.26.0.206154.26.0.2072
53154.26.0.208/30154.26.0.209 to 154.26.0.210154.26.0.2112
54154.26.0.212/30154.26.0.213 to 154.26.0.214154.26.0.2152
55154.26.0.216/30154.26.0.217 to 154.26.0.218154.26.0.2192
56154.26.0.220/30154.26.0.221 to 154.26.0.222154.26.0.2232
57154.26.0.224/30154.26.0.225 to 154.26.0.226154.26.0.2272
58154.26.0.228/30154.26.0.229 to 154.26.0.230154.26.0.2312
59154.26.0.232/30154.26.0.233 to 154.26.0.234154.26.0.2352
60154.26.0.236/30154.26.0.237 to 154.26.0.238154.26.0.2392
61154.26.0.240/30154.26.0.241 to 154.26.0.242154.26.0.2432
62154.26.0.244/30154.26.0.245 to 154.26.0.246154.26.0.2472
63154.26.0.248/30154.26.0.249 to 154.26.0.250154.26.0.2512
64154.26.0.252/30154.26.0.253 to 154.26.0.254154.26.0.2552
65154.26.1.0/30154.26.1.1 to 154.26.1.2154.26.1.32
66154.26.1.4/30154.26.1.5 to 154.26.1.6154.26.1.72
67154.26.1.8/30154.26.1.9 to 154.26.1.10154.26.1.112
68154.26.1.12/30154.26.1.13 to 154.26.1.14154.26.1.152
69154.26.1.16/30154.26.1.17 to 154.26.1.18154.26.1.192
70154.26.1.20/30154.26.1.21 to 154.26.1.22154.26.1.232
71154.26.1.24/30154.26.1.25 to 154.26.1.26154.26.1.272
72154.26.1.28/30154.26.1.29 to 154.26.1.30154.26.1.312
73154.26.1.32/30154.26.1.33 to 154.26.1.34154.26.1.352
74154.26.1.36/30154.26.1.37 to 154.26.1.38154.26.1.392
75154.26.1.40/30154.26.1.41 to 154.26.1.42154.26.1.432
76154.26.1.44/30154.26.1.45 to 154.26.1.46154.26.1.472
77154.26.1.48/30154.26.1.49 to 154.26.1.50154.26.1.512
78154.26.1.52/30154.26.1.53 to 154.26.1.54154.26.1.552
79154.26.1.56/30154.26.1.57 to 154.26.1.58154.26.1.592
80154.26.1.60/30154.26.1.61 to 154.26.1.62154.26.1.632
81154.26.1.64/30154.26.1.65 to 154.26.1.66154.26.1.672
82154.26.1.68/30154.26.1.69 to 154.26.1.70154.26.1.712
83154.26.1.72/30154.26.1.73 to 154.26.1.74154.26.1.752
84154.26.1.76/30154.26.1.77 to 154.26.1.78154.26.1.792
85154.26.1.80/30154.26.1.81 to 154.26.1.82154.26.1.832
86154.26.1.84/30154.26.1.85 to 154.26.1.86154.26.1.872
87154.26.1.88/30154.26.1.89 to 154.26.1.90154.26.1.912
88154.26.1.92/30154.26.1.93 to 154.26.1.94154.26.1.952
89154.26.1.96/30154.26.1.97 to 154.26.1.98154.26.1.992
90154.26.1.100/30154.26.1.101 to 154.26.1.102154.26.1.1032
91154.26.1.104/30154.26.1.105 to 154.26.1.106154.26.1.1072
92154.26.1.108/30154.26.1.109 to 154.26.1.110154.26.1.1112
93154.26.1.112/30154.26.1.113 to 154.26.1.114154.26.1.1152
94154.26.1.116/30154.26.1.117 to 154.26.1.118154.26.1.1192
95154.26.1.120/30154.26.1.121 to 154.26.1.122154.26.1.1232
96154.26.1.124/30154.26.1.125 to 154.26.1.126154.26.1.1272
97154.26.1.128/30154.26.1.129 to 154.26.1.130154.26.1.1312
98154.26.1.132/30154.26.1.133 to 154.26.1.134154.26.1.1352
99154.26.1.136/30154.26.1.137 to 154.26.1.138154.26.1.1392
100154.26.1.140/30154.26.1.141 to 154.26.1.142154.26.1.1432
101154.26.1.144/30154.26.1.145 to 154.26.1.146154.26.1.1472
102154.26.1.148/30154.26.1.149 to 154.26.1.150154.26.1.1512
103154.26.1.152/30154.26.1.153 to 154.26.1.154154.26.1.1552
104154.26.1.156/30154.26.1.157 to 154.26.1.158154.26.1.1592
105154.26.1.160/30154.26.1.161 to 154.26.1.162154.26.1.1632
106154.26.1.164/30154.26.1.165 to 154.26.1.166154.26.1.1672
107154.26.1.168/30154.26.1.169 to 154.26.1.170154.26.1.1712
108154.26.1.172/30154.26.1.173 to 154.26.1.174154.26.1.1752
109154.26.1.176/30154.26.1.177 to 154.26.1.178154.26.1.1792
110154.26.1.180/30154.26.1.181 to 154.26.1.182154.26.1.1832
111154.26.1.184/30154.26.1.185 to 154.26.1.186154.26.1.1872
112154.26.1.188/30154.26.1.189 to 154.26.1.190154.26.1.1912
113154.26.1.192/30154.26.1.193 to 154.26.1.194154.26.1.1952
114154.26.1.196/30154.26.1.197 to 154.26.1.198154.26.1.1992
115154.26.1.200/30154.26.1.201 to 154.26.1.202154.26.1.2032
116154.26.1.204/30154.26.1.205 to 154.26.1.206154.26.1.2072
117154.26.1.208/30154.26.1.209 to 154.26.1.210154.26.1.2112
118154.26.1.212/30154.26.1.213 to 154.26.1.214154.26.1.2152
119154.26.1.216/30154.26.1.217 to 154.26.1.218154.26.1.2192
120154.26.1.220/30154.26.1.221 to 154.26.1.222154.26.1.2232
121154.26.1.224/30154.26.1.225 to 154.26.1.226154.26.1.2272
122154.26.1.228/30154.26.1.229 to 154.26.1.230154.26.1.2312
123154.26.1.232/30154.26.1.233 to 154.26.1.234154.26.1.2352
124154.26.1.236/30154.26.1.237 to 154.26.1.238154.26.1.2392
125154.26.1.240/30154.26.1.241 to 154.26.1.242154.26.1.2432
126154.26.1.244/30154.26.1.245 to 154.26.1.246154.26.1.2472
127154.26.1.248/30154.26.1.249 to 154.26.1.250154.26.1.2512
128154.26.1.252/30154.26.1.253 to 154.26.1.254154.26.1.2552
129154.26.2.0/30154.26.2.1 to 154.26.2.2154.26.2.32
130154.26.2.4/30154.26.2.5 to 154.26.2.6154.26.2.72
131154.26.2.8/30154.26.2.9 to 154.26.2.10154.26.2.112
132154.26.2.12/30154.26.2.13 to 154.26.2.14154.26.2.152
133154.26.2.16/30154.26.2.17 to 154.26.2.18154.26.2.192
134154.26.2.20/30154.26.2.21 to 154.26.2.22154.26.2.232
135154.26.2.24/30154.26.2.25 to 154.26.2.26154.26.2.272
136154.26.2.28/30154.26.2.29 to 154.26.2.30154.26.2.312
137154.26.2.32/30154.26.2.33 to 154.26.2.34154.26.2.352
138154.26.2.36/30154.26.2.37 to 154.26.2.38154.26.2.392
139154.26.2.40/30154.26.2.41 to 154.26.2.42154.26.2.432
140154.26.2.44/30154.26.2.45 to 154.26.2.46154.26.2.472
141154.26.2.48/30154.26.2.49 to 154.26.2.50154.26.2.512
142154.26.2.52/30154.26.2.53 to 154.26.2.54154.26.2.552
143154.26.2.56/30154.26.2.57 to 154.26.2.58154.26.2.592
144154.26.2.60/30154.26.2.61 to 154.26.2.62154.26.2.632
145154.26.2.64/30154.26.2.65 to 154.26.2.66154.26.2.672
146154.26.2.68/30154.26.2.69 to 154.26.2.70154.26.2.712
147154.26.2.72/30154.26.2.73 to 154.26.2.74154.26.2.752
148154.26.2.76/30154.26.2.77 to 154.26.2.78154.26.2.792
149154.26.2.80/30154.26.2.81 to 154.26.2.82154.26.2.832
150154.26.2.84/30154.26.2.85 to 154.26.2.86154.26.2.872
151154.26.2.88/30154.26.2.89 to 154.26.2.90154.26.2.912
152154.26.2.92/30154.26.2.93 to 154.26.2.94154.26.2.952
153154.26.2.96/30154.26.2.97 to 154.26.2.98154.26.2.992
154154.26.2.100/30154.26.2.101 to 154.26.2.102154.26.2.1032
155154.26.2.104/30154.26.2.105 to 154.26.2.106154.26.2.1072
156154.26.2.108/30154.26.2.109 to 154.26.2.110154.26.2.1112
157154.26.2.112/30154.26.2.113 to 154.26.2.114154.26.2.1152
158154.26.2.116/30154.26.2.117 to 154.26.2.118154.26.2.1192
159154.26.2.120/30154.26.2.121 to 154.26.2.122154.26.2.1232
160154.26.2.124/30154.26.2.125 to 154.26.2.126154.26.2.1272
161154.26.2.128/30154.26.2.129 to 154.26.2.130154.26.2.1312
162154.26.2.132/30154.26.2.133 to 154.26.2.134154.26.2.1352
163154.26.2.136/30154.26.2.137 to 154.26.2.138154.26.2.1392
164154.26.2.140/30154.26.2.141 to 154.26.2.142154.26.2.1432
165154.26.2.144/30154.26.2.145 to 154.26.2.146154.26.2.1472
166154.26.2.148/30154.26.2.149 to 154.26.2.150154.26.2.1512
167154.26.2.152/30154.26.2.153 to 154.26.2.154154.26.2.1552
168154.26.2.156/30154.26.2.157 to 154.26.2.158154.26.2.1592
169154.26.2.160/30154.26.2.161 to 154.26.2.162154.26.2.1632
170154.26.2.164/30154.26.2.165 to 154.26.2.166154.26.2.1672
171154.26.2.168/30154.26.2.169 to 154.26.2.170154.26.2.1712
172154.26.2.172/30154.26.2.173 to 154.26.2.174154.26.2.1752
173154.26.2.176/30154.26.2.177 to 154.26.2.178154.26.2.1792
174154.26.2.180/30154.26.2.181 to 154.26.2.182154.26.2.1832
175154.26.2.184/30154.26.2.185 to 154.26.2.186154.26.2.1872
176154.26.2.188/30154.26.2.189 to 154.26.2.190154.26.2.1912
177154.26.2.192/30154.26.2.193 to 154.26.2.194154.26.2.1952
178154.26.2.196/30154.26.2.197 to 154.26.2.198154.26.2.1992
179154.26.2.200/30154.26.2.201 to 154.26.2.202154.26.2.2032
180154.26.2.204/30154.26.2.205 to 154.26.2.206154.26.2.2072
181154.26.2.208/30154.26.2.209 to 154.26.2.210154.26.2.2112
182154.26.2.212/30154.26.2.213 to 154.26.2.214154.26.2.2152
183154.26.2.216/30154.26.2.217 to 154.26.2.218154.26.2.2192
184154.26.2.220/30154.26.2.221 to 154.26.2.222154.26.2.2232
185154.26.2.224/30154.26.2.225 to 154.26.2.226154.26.2.2272
186154.26.2.228/30154.26.2.229 to 154.26.2.230154.26.2.2312
187154.26.2.232/30154.26.2.233 to 154.26.2.234154.26.2.2352
188154.26.2.236/30154.26.2.237 to 154.26.2.238154.26.2.2392
189154.26.2.240/30154.26.2.241 to 154.26.2.242154.26.2.2432
190154.26.2.244/30154.26.2.245 to 154.26.2.246154.26.2.2472
191154.26.2.248/30154.26.2.249 to 154.26.2.250154.26.2.2512
192154.26.2.252/30154.26.2.253 to 154.26.2.254154.26.2.2552
193154.26.3.0/30154.26.3.1 to 154.26.3.2154.26.3.32
194154.26.3.4/30154.26.3.5 to 154.26.3.6154.26.3.72
195154.26.3.8/30154.26.3.9 to 154.26.3.10154.26.3.112
196154.26.3.12/30154.26.3.13 to 154.26.3.14154.26.3.152
197154.26.3.16/30154.26.3.17 to 154.26.3.18154.26.3.192
198154.26.3.20/30154.26.3.21 to 154.26.3.22154.26.3.232
199154.26.3.24/30154.26.3.25 to 154.26.3.26154.26.3.272
200154.26.3.28/30154.26.3.29 to 154.26.3.30154.26.3.312
201154.26.3.32/30154.26.3.33 to 154.26.3.34154.26.3.352
202154.26.3.36/30154.26.3.37 to 154.26.3.38154.26.3.392
203154.26.3.40/30154.26.3.41 to 154.26.3.42154.26.3.432
204154.26.3.44/30154.26.3.45 to 154.26.3.46154.26.3.472
205154.26.3.48/30154.26.3.49 to 154.26.3.50154.26.3.512
206154.26.3.52/30154.26.3.53 to 154.26.3.54154.26.3.552
207154.26.3.56/30154.26.3.57 to 154.26.3.58154.26.3.592
208154.26.3.60/30154.26.3.61 to 154.26.3.62154.26.3.632
209154.26.3.64/30154.26.3.65 to 154.26.3.66154.26.3.672
210154.26.3.68/30154.26.3.69 to 154.26.3.70154.26.3.712
211154.26.3.72/30154.26.3.73 to 154.26.3.74154.26.3.752
212154.26.3.76/30154.26.3.77 to 154.26.3.78154.26.3.792
213154.26.3.80/30154.26.3.81 to 154.26.3.82154.26.3.832
214154.26.3.84/30154.26.3.85 to 154.26.3.86154.26.3.872
215154.26.3.88/30154.26.3.89 to 154.26.3.90154.26.3.912
216154.26.3.92/30154.26.3.93 to 154.26.3.94154.26.3.952
217154.26.3.96/30154.26.3.97 to 154.26.3.98154.26.3.992
218154.26.3.100/30154.26.3.101 to 154.26.3.102154.26.3.1032
219154.26.3.104/30154.26.3.105 to 154.26.3.106154.26.3.1072
220154.26.3.108/30154.26.3.109 to 154.26.3.110154.26.3.1112
221154.26.3.112/30154.26.3.113 to 154.26.3.114154.26.3.1152
222154.26.3.116/30154.26.3.117 to 154.26.3.118154.26.3.1192
223154.26.3.120/30154.26.3.121 to 154.26.3.122154.26.3.1232
224154.26.3.124/30154.26.3.125 to 154.26.3.126154.26.3.1272
225154.26.3.128/30154.26.3.129 to 154.26.3.130154.26.3.1312
226154.26.3.132/30154.26.3.133 to 154.26.3.134154.26.3.1352
227154.26.3.136/30154.26.3.137 to 154.26.3.138154.26.3.1392
228154.26.3.140/30154.26.3.141 to 154.26.3.142154.26.3.1432
229154.26.3.144/30154.26.3.145 to 154.26.3.146154.26.3.1472
230154.26.3.148/30154.26.3.149 to 154.26.3.150154.26.3.1512
231154.26.3.152/30154.26.3.153 to 154.26.3.154154.26.3.1552
232154.26.3.156/30154.26.3.157 to 154.26.3.158154.26.3.1592
233154.26.3.160/30154.26.3.161 to 154.26.3.162154.26.3.1632
234154.26.3.164/30154.26.3.165 to 154.26.3.166154.26.3.1672
235154.26.3.168/30154.26.3.169 to 154.26.3.170154.26.3.1712
236154.26.3.172/30154.26.3.173 to 154.26.3.174154.26.3.1752
237154.26.3.176/30154.26.3.177 to 154.26.3.178154.26.3.1792
238154.26.3.180/30154.26.3.181 to 154.26.3.182154.26.3.1832
239154.26.3.184/30154.26.3.185 to 154.26.3.186154.26.3.1872
240154.26.3.188/30154.26.3.189 to 154.26.3.190154.26.3.1912
241154.26.3.192/30154.26.3.193 to 154.26.3.194154.26.3.1952
242154.26.3.196/30154.26.3.197 to 154.26.3.198154.26.3.1992
243154.26.3.200/30154.26.3.201 to 154.26.3.202154.26.3.2032
244154.26.3.204/30154.26.3.205 to 154.26.3.206154.26.3.2072
245154.26.3.208/30154.26.3.209 to 154.26.3.210154.26.3.2112
246154.26.3.212/30154.26.3.213 to 154.26.3.214154.26.3.2152
247154.26.3.216/30154.26.3.217 to 154.26.3.218154.26.3.2192
248154.26.3.220/30154.26.3.221 to 154.26.3.222154.26.3.2232
249154.26.3.224/30154.26.3.225 to 154.26.3.226154.26.3.2272
250154.26.3.228/30154.26.3.229 to 154.26.3.230154.26.3.2312
251154.26.3.232/30154.26.3.233 to 154.26.3.234154.26.3.2352
252154.26.3.236/30154.26.3.237 to 154.26.3.238154.26.3.2392
253154.26.3.240/30154.26.3.241 to 154.26.3.242154.26.3.2432
254154.26.3.244/30154.26.3.245 to 154.26.3.246154.26.3.2472
255154.26.3.248/30154.26.3.249 to 154.26.3.250154.26.3.2512
256154.26.3.252/30154.26.3.253 to 154.26.3.254154.26.3.2552

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.