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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.

Network160.78.0.0/17
Usable hosts32,766
Subnet mask255.255.128.0
Addresses32,768
Network address
160.78.0.0
Broadcast address
160.78.127.255
First usable
160.78.0.1
Last usable
160.78.127.254
Usable hosts
32,766 (32,768 less the network and broadcast addresses)
Subnet mask
255.255.128.0
Wildcard mask
0.0.127.255 (Cisco ACLs, OSPF)
Prefix length
/17
Type
Public public
Old class
B (default /16)
As numbers
Hex A04E0000 · Integer 2689466368 to 2689499135
Reverse DNS zones
0.78.160.in-addr.arpa
1.78.160.in-addr.arpa
2.78.160.in-addr.arpa
3.78.160.in-addr.arpa
4.78.160.in-addr.arpa
5.78.160.in-addr.arpa
6.78.160.in-addr.arpa
7.78.160.in-addr.arpa
8.78.160.in-addr.arpa
9.78.160.in-addr.arpa
10.78.160.in-addr.arpa
11.78.160.in-addr.arpa
12.78.160.in-addr.arpa
13.78.160.in-addr.arpa
14.78.160.in-addr.arpa
15.78.160.in-addr.arpa
and 112 more
/17 is not on a 8-bit boundary, so it takes 128 /24 zones.
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address10100000.01001110.00000000.00000000160.78.0.0
Subnet mask11111111.11111111.10000000.00000000255.255.128.0
Network10100000.01001110.00000000.00000000160.78.0.0
Broadcast10100000.01001110.01111111.11111111160.78.127.255
Split into smaller subnets/28
/18 (2)/19 (4)/20 (8)/21 (16)/22 (32)/23 (64)/24 (128)/25 (256)/26 (512)/27 (1,024)/28 (2,048)/29 (4,096)

160.78.0.0/17 makes 2,048 subnets of /28; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
1160.78.0.0/28160.78.0.1 to 160.78.0.14160.78.0.1514
2160.78.0.16/28160.78.0.17 to 160.78.0.30160.78.0.3114
3160.78.0.32/28160.78.0.33 to 160.78.0.46160.78.0.4714
4160.78.0.48/28160.78.0.49 to 160.78.0.62160.78.0.6314
5160.78.0.64/28160.78.0.65 to 160.78.0.78160.78.0.7914
6160.78.0.80/28160.78.0.81 to 160.78.0.94160.78.0.9514
7160.78.0.96/28160.78.0.97 to 160.78.0.110160.78.0.11114
8160.78.0.112/28160.78.0.113 to 160.78.0.126160.78.0.12714
9160.78.0.128/28160.78.0.129 to 160.78.0.142160.78.0.14314
10160.78.0.144/28160.78.0.145 to 160.78.0.158160.78.0.15914
11160.78.0.160/28160.78.0.161 to 160.78.0.174160.78.0.17514
12160.78.0.176/28160.78.0.177 to 160.78.0.190160.78.0.19114
13160.78.0.192/28160.78.0.193 to 160.78.0.206160.78.0.20714
14160.78.0.208/28160.78.0.209 to 160.78.0.222160.78.0.22314
15160.78.0.224/28160.78.0.225 to 160.78.0.238160.78.0.23914
16160.78.0.240/28160.78.0.241 to 160.78.0.254160.78.0.25514
17160.78.1.0/28160.78.1.1 to 160.78.1.14160.78.1.1514
18160.78.1.16/28160.78.1.17 to 160.78.1.30160.78.1.3114
19160.78.1.32/28160.78.1.33 to 160.78.1.46160.78.1.4714
20160.78.1.48/28160.78.1.49 to 160.78.1.62160.78.1.6314
21160.78.1.64/28160.78.1.65 to 160.78.1.78160.78.1.7914
22160.78.1.80/28160.78.1.81 to 160.78.1.94160.78.1.9514
23160.78.1.96/28160.78.1.97 to 160.78.1.110160.78.1.11114
24160.78.1.112/28160.78.1.113 to 160.78.1.126160.78.1.12714
25160.78.1.128/28160.78.1.129 to 160.78.1.142160.78.1.14314
26160.78.1.144/28160.78.1.145 to 160.78.1.158160.78.1.15914
27160.78.1.160/28160.78.1.161 to 160.78.1.174160.78.1.17514
28160.78.1.176/28160.78.1.177 to 160.78.1.190160.78.1.19114
29160.78.1.192/28160.78.1.193 to 160.78.1.206160.78.1.20714
30160.78.1.208/28160.78.1.209 to 160.78.1.222160.78.1.22314
31160.78.1.224/28160.78.1.225 to 160.78.1.238160.78.1.23914
32160.78.1.240/28160.78.1.241 to 160.78.1.254160.78.1.25514
33160.78.2.0/28160.78.2.1 to 160.78.2.14160.78.2.1514
34160.78.2.16/28160.78.2.17 to 160.78.2.30160.78.2.3114
35160.78.2.32/28160.78.2.33 to 160.78.2.46160.78.2.4714
36160.78.2.48/28160.78.2.49 to 160.78.2.62160.78.2.6314
37160.78.2.64/28160.78.2.65 to 160.78.2.78160.78.2.7914
38160.78.2.80/28160.78.2.81 to 160.78.2.94160.78.2.9514
39160.78.2.96/28160.78.2.97 to 160.78.2.110160.78.2.11114
40160.78.2.112/28160.78.2.113 to 160.78.2.126160.78.2.12714
41160.78.2.128/28160.78.2.129 to 160.78.2.142160.78.2.14314
42160.78.2.144/28160.78.2.145 to 160.78.2.158160.78.2.15914
43160.78.2.160/28160.78.2.161 to 160.78.2.174160.78.2.17514
44160.78.2.176/28160.78.2.177 to 160.78.2.190160.78.2.19114
45160.78.2.192/28160.78.2.193 to 160.78.2.206160.78.2.20714
46160.78.2.208/28160.78.2.209 to 160.78.2.222160.78.2.22314
47160.78.2.224/28160.78.2.225 to 160.78.2.238160.78.2.23914
48160.78.2.240/28160.78.2.241 to 160.78.2.254160.78.2.25514
49160.78.3.0/28160.78.3.1 to 160.78.3.14160.78.3.1514
50160.78.3.16/28160.78.3.17 to 160.78.3.30160.78.3.3114
51160.78.3.32/28160.78.3.33 to 160.78.3.46160.78.3.4714
52160.78.3.48/28160.78.3.49 to 160.78.3.62160.78.3.6314
53160.78.3.64/28160.78.3.65 to 160.78.3.78160.78.3.7914
54160.78.3.80/28160.78.3.81 to 160.78.3.94160.78.3.9514
55160.78.3.96/28160.78.3.97 to 160.78.3.110160.78.3.11114
56160.78.3.112/28160.78.3.113 to 160.78.3.126160.78.3.12714
57160.78.3.128/28160.78.3.129 to 160.78.3.142160.78.3.14314
58160.78.3.144/28160.78.3.145 to 160.78.3.158160.78.3.15914
59160.78.3.160/28160.78.3.161 to 160.78.3.174160.78.3.17514
60160.78.3.176/28160.78.3.177 to 160.78.3.190160.78.3.19114
61160.78.3.192/28160.78.3.193 to 160.78.3.206160.78.3.20714
62160.78.3.208/28160.78.3.209 to 160.78.3.222160.78.3.22314
63160.78.3.224/28160.78.3.225 to 160.78.3.238160.78.3.23914
64160.78.3.240/28160.78.3.241 to 160.78.3.254160.78.3.25514
65160.78.4.0/28160.78.4.1 to 160.78.4.14160.78.4.1514
66160.78.4.16/28160.78.4.17 to 160.78.4.30160.78.4.3114
67160.78.4.32/28160.78.4.33 to 160.78.4.46160.78.4.4714
68160.78.4.48/28160.78.4.49 to 160.78.4.62160.78.4.6314
69160.78.4.64/28160.78.4.65 to 160.78.4.78160.78.4.7914
70160.78.4.80/28160.78.4.81 to 160.78.4.94160.78.4.9514
71160.78.4.96/28160.78.4.97 to 160.78.4.110160.78.4.11114
72160.78.4.112/28160.78.4.113 to 160.78.4.126160.78.4.12714
73160.78.4.128/28160.78.4.129 to 160.78.4.142160.78.4.14314
74160.78.4.144/28160.78.4.145 to 160.78.4.158160.78.4.15914
75160.78.4.160/28160.78.4.161 to 160.78.4.174160.78.4.17514
76160.78.4.176/28160.78.4.177 to 160.78.4.190160.78.4.19114
77160.78.4.192/28160.78.4.193 to 160.78.4.206160.78.4.20714
78160.78.4.208/28160.78.4.209 to 160.78.4.222160.78.4.22314
79160.78.4.224/28160.78.4.225 to 160.78.4.238160.78.4.23914
80160.78.4.240/28160.78.4.241 to 160.78.4.254160.78.4.25514
81160.78.5.0/28160.78.5.1 to 160.78.5.14160.78.5.1514
82160.78.5.16/28160.78.5.17 to 160.78.5.30160.78.5.3114
83160.78.5.32/28160.78.5.33 to 160.78.5.46160.78.5.4714
84160.78.5.48/28160.78.5.49 to 160.78.5.62160.78.5.6314
85160.78.5.64/28160.78.5.65 to 160.78.5.78160.78.5.7914
86160.78.5.80/28160.78.5.81 to 160.78.5.94160.78.5.9514
87160.78.5.96/28160.78.5.97 to 160.78.5.110160.78.5.11114
88160.78.5.112/28160.78.5.113 to 160.78.5.126160.78.5.12714
89160.78.5.128/28160.78.5.129 to 160.78.5.142160.78.5.14314
90160.78.5.144/28160.78.5.145 to 160.78.5.158160.78.5.15914
91160.78.5.160/28160.78.5.161 to 160.78.5.174160.78.5.17514
92160.78.5.176/28160.78.5.177 to 160.78.5.190160.78.5.19114
93160.78.5.192/28160.78.5.193 to 160.78.5.206160.78.5.20714
94160.78.5.208/28160.78.5.209 to 160.78.5.222160.78.5.22314
95160.78.5.224/28160.78.5.225 to 160.78.5.238160.78.5.23914
96160.78.5.240/28160.78.5.241 to 160.78.5.254160.78.5.25514
97160.78.6.0/28160.78.6.1 to 160.78.6.14160.78.6.1514
98160.78.6.16/28160.78.6.17 to 160.78.6.30160.78.6.3114
99160.78.6.32/28160.78.6.33 to 160.78.6.46160.78.6.4714
100160.78.6.48/28160.78.6.49 to 160.78.6.62160.78.6.6314
101160.78.6.64/28160.78.6.65 to 160.78.6.78160.78.6.7914
102160.78.6.80/28160.78.6.81 to 160.78.6.94160.78.6.9514
103160.78.6.96/28160.78.6.97 to 160.78.6.110160.78.6.11114
104160.78.6.112/28160.78.6.113 to 160.78.6.126160.78.6.12714
105160.78.6.128/28160.78.6.129 to 160.78.6.142160.78.6.14314
106160.78.6.144/28160.78.6.145 to 160.78.6.158160.78.6.15914
107160.78.6.160/28160.78.6.161 to 160.78.6.174160.78.6.17514
108160.78.6.176/28160.78.6.177 to 160.78.6.190160.78.6.19114
109160.78.6.192/28160.78.6.193 to 160.78.6.206160.78.6.20714
110160.78.6.208/28160.78.6.209 to 160.78.6.222160.78.6.22314
111160.78.6.224/28160.78.6.225 to 160.78.6.238160.78.6.23914
112160.78.6.240/28160.78.6.241 to 160.78.6.254160.78.6.25514
113160.78.7.0/28160.78.7.1 to 160.78.7.14160.78.7.1514
114160.78.7.16/28160.78.7.17 to 160.78.7.30160.78.7.3114
115160.78.7.32/28160.78.7.33 to 160.78.7.46160.78.7.4714
116160.78.7.48/28160.78.7.49 to 160.78.7.62160.78.7.6314
117160.78.7.64/28160.78.7.65 to 160.78.7.78160.78.7.7914
118160.78.7.80/28160.78.7.81 to 160.78.7.94160.78.7.9514
119160.78.7.96/28160.78.7.97 to 160.78.7.110160.78.7.11114
120160.78.7.112/28160.78.7.113 to 160.78.7.126160.78.7.12714
121160.78.7.128/28160.78.7.129 to 160.78.7.142160.78.7.14314
122160.78.7.144/28160.78.7.145 to 160.78.7.158160.78.7.15914
123160.78.7.160/28160.78.7.161 to 160.78.7.174160.78.7.17514
124160.78.7.176/28160.78.7.177 to 160.78.7.190160.78.7.19114
125160.78.7.192/28160.78.7.193 to 160.78.7.206160.78.7.20714
126160.78.7.208/28160.78.7.209 to 160.78.7.222160.78.7.22314
127160.78.7.224/28160.78.7.225 to 160.78.7.238160.78.7.23914
128160.78.7.240/28160.78.7.241 to 160.78.7.254160.78.7.25514
129160.78.8.0/28160.78.8.1 to 160.78.8.14160.78.8.1514
130160.78.8.16/28160.78.8.17 to 160.78.8.30160.78.8.3114
131160.78.8.32/28160.78.8.33 to 160.78.8.46160.78.8.4714
132160.78.8.48/28160.78.8.49 to 160.78.8.62160.78.8.6314
133160.78.8.64/28160.78.8.65 to 160.78.8.78160.78.8.7914
134160.78.8.80/28160.78.8.81 to 160.78.8.94160.78.8.9514
135160.78.8.96/28160.78.8.97 to 160.78.8.110160.78.8.11114
136160.78.8.112/28160.78.8.113 to 160.78.8.126160.78.8.12714
137160.78.8.128/28160.78.8.129 to 160.78.8.142160.78.8.14314
138160.78.8.144/28160.78.8.145 to 160.78.8.158160.78.8.15914
139160.78.8.160/28160.78.8.161 to 160.78.8.174160.78.8.17514
140160.78.8.176/28160.78.8.177 to 160.78.8.190160.78.8.19114
141160.78.8.192/28160.78.8.193 to 160.78.8.206160.78.8.20714
142160.78.8.208/28160.78.8.209 to 160.78.8.222160.78.8.22314
143160.78.8.224/28160.78.8.225 to 160.78.8.238160.78.8.23914
144160.78.8.240/28160.78.8.241 to 160.78.8.254160.78.8.25514
145160.78.9.0/28160.78.9.1 to 160.78.9.14160.78.9.1514
146160.78.9.16/28160.78.9.17 to 160.78.9.30160.78.9.3114
147160.78.9.32/28160.78.9.33 to 160.78.9.46160.78.9.4714
148160.78.9.48/28160.78.9.49 to 160.78.9.62160.78.9.6314
149160.78.9.64/28160.78.9.65 to 160.78.9.78160.78.9.7914
150160.78.9.80/28160.78.9.81 to 160.78.9.94160.78.9.9514
151160.78.9.96/28160.78.9.97 to 160.78.9.110160.78.9.11114
152160.78.9.112/28160.78.9.113 to 160.78.9.126160.78.9.12714
153160.78.9.128/28160.78.9.129 to 160.78.9.142160.78.9.14314
154160.78.9.144/28160.78.9.145 to 160.78.9.158160.78.9.15914
155160.78.9.160/28160.78.9.161 to 160.78.9.174160.78.9.17514
156160.78.9.176/28160.78.9.177 to 160.78.9.190160.78.9.19114
157160.78.9.192/28160.78.9.193 to 160.78.9.206160.78.9.20714
158160.78.9.208/28160.78.9.209 to 160.78.9.222160.78.9.22314
159160.78.9.224/28160.78.9.225 to 160.78.9.238160.78.9.23914
160160.78.9.240/28160.78.9.241 to 160.78.9.254160.78.9.25514
161160.78.10.0/28160.78.10.1 to 160.78.10.14160.78.10.1514
162160.78.10.16/28160.78.10.17 to 160.78.10.30160.78.10.3114
163160.78.10.32/28160.78.10.33 to 160.78.10.46160.78.10.4714
164160.78.10.48/28160.78.10.49 to 160.78.10.62160.78.10.6314
165160.78.10.64/28160.78.10.65 to 160.78.10.78160.78.10.7914
166160.78.10.80/28160.78.10.81 to 160.78.10.94160.78.10.9514
167160.78.10.96/28160.78.10.97 to 160.78.10.110160.78.10.11114
168160.78.10.112/28160.78.10.113 to 160.78.10.126160.78.10.12714
169160.78.10.128/28160.78.10.129 to 160.78.10.142160.78.10.14314
170160.78.10.144/28160.78.10.145 to 160.78.10.158160.78.10.15914
171160.78.10.160/28160.78.10.161 to 160.78.10.174160.78.10.17514
172160.78.10.176/28160.78.10.177 to 160.78.10.190160.78.10.19114
173160.78.10.192/28160.78.10.193 to 160.78.10.206160.78.10.20714
174160.78.10.208/28160.78.10.209 to 160.78.10.222160.78.10.22314
175160.78.10.224/28160.78.10.225 to 160.78.10.238160.78.10.23914
176160.78.10.240/28160.78.10.241 to 160.78.10.254160.78.10.25514
177160.78.11.0/28160.78.11.1 to 160.78.11.14160.78.11.1514
178160.78.11.16/28160.78.11.17 to 160.78.11.30160.78.11.3114
179160.78.11.32/28160.78.11.33 to 160.78.11.46160.78.11.4714
180160.78.11.48/28160.78.11.49 to 160.78.11.62160.78.11.6314
181160.78.11.64/28160.78.11.65 to 160.78.11.78160.78.11.7914
182160.78.11.80/28160.78.11.81 to 160.78.11.94160.78.11.9514
183160.78.11.96/28160.78.11.97 to 160.78.11.110160.78.11.11114
184160.78.11.112/28160.78.11.113 to 160.78.11.126160.78.11.12714
185160.78.11.128/28160.78.11.129 to 160.78.11.142160.78.11.14314
186160.78.11.144/28160.78.11.145 to 160.78.11.158160.78.11.15914
187160.78.11.160/28160.78.11.161 to 160.78.11.174160.78.11.17514
188160.78.11.176/28160.78.11.177 to 160.78.11.190160.78.11.19114
189160.78.11.192/28160.78.11.193 to 160.78.11.206160.78.11.20714
190160.78.11.208/28160.78.11.209 to 160.78.11.222160.78.11.22314
191160.78.11.224/28160.78.11.225 to 160.78.11.238160.78.11.23914
192160.78.11.240/28160.78.11.241 to 160.78.11.254160.78.11.25514
193160.78.12.0/28160.78.12.1 to 160.78.12.14160.78.12.1514
194160.78.12.16/28160.78.12.17 to 160.78.12.30160.78.12.3114
195160.78.12.32/28160.78.12.33 to 160.78.12.46160.78.12.4714
196160.78.12.48/28160.78.12.49 to 160.78.12.62160.78.12.6314
197160.78.12.64/28160.78.12.65 to 160.78.12.78160.78.12.7914
198160.78.12.80/28160.78.12.81 to 160.78.12.94160.78.12.9514
199160.78.12.96/28160.78.12.97 to 160.78.12.110160.78.12.11114
200160.78.12.112/28160.78.12.113 to 160.78.12.126160.78.12.12714
201160.78.12.128/28160.78.12.129 to 160.78.12.142160.78.12.14314
202160.78.12.144/28160.78.12.145 to 160.78.12.158160.78.12.15914
203160.78.12.160/28160.78.12.161 to 160.78.12.174160.78.12.17514
204160.78.12.176/28160.78.12.177 to 160.78.12.190160.78.12.19114
205160.78.12.192/28160.78.12.193 to 160.78.12.206160.78.12.20714
206160.78.12.208/28160.78.12.209 to 160.78.12.222160.78.12.22314
207160.78.12.224/28160.78.12.225 to 160.78.12.238160.78.12.23914
208160.78.12.240/28160.78.12.241 to 160.78.12.254160.78.12.25514
209160.78.13.0/28160.78.13.1 to 160.78.13.14160.78.13.1514
210160.78.13.16/28160.78.13.17 to 160.78.13.30160.78.13.3114
211160.78.13.32/28160.78.13.33 to 160.78.13.46160.78.13.4714
212160.78.13.48/28160.78.13.49 to 160.78.13.62160.78.13.6314
213160.78.13.64/28160.78.13.65 to 160.78.13.78160.78.13.7914
214160.78.13.80/28160.78.13.81 to 160.78.13.94160.78.13.9514
215160.78.13.96/28160.78.13.97 to 160.78.13.110160.78.13.11114
216160.78.13.112/28160.78.13.113 to 160.78.13.126160.78.13.12714
217160.78.13.128/28160.78.13.129 to 160.78.13.142160.78.13.14314
218160.78.13.144/28160.78.13.145 to 160.78.13.158160.78.13.15914
219160.78.13.160/28160.78.13.161 to 160.78.13.174160.78.13.17514
220160.78.13.176/28160.78.13.177 to 160.78.13.190160.78.13.19114
221160.78.13.192/28160.78.13.193 to 160.78.13.206160.78.13.20714
222160.78.13.208/28160.78.13.209 to 160.78.13.222160.78.13.22314
223160.78.13.224/28160.78.13.225 to 160.78.13.238160.78.13.23914
224160.78.13.240/28160.78.13.241 to 160.78.13.254160.78.13.25514
225160.78.14.0/28160.78.14.1 to 160.78.14.14160.78.14.1514
226160.78.14.16/28160.78.14.17 to 160.78.14.30160.78.14.3114
227160.78.14.32/28160.78.14.33 to 160.78.14.46160.78.14.4714
228160.78.14.48/28160.78.14.49 to 160.78.14.62160.78.14.6314
229160.78.14.64/28160.78.14.65 to 160.78.14.78160.78.14.7914
230160.78.14.80/28160.78.14.81 to 160.78.14.94160.78.14.9514
231160.78.14.96/28160.78.14.97 to 160.78.14.110160.78.14.11114
232160.78.14.112/28160.78.14.113 to 160.78.14.126160.78.14.12714
233160.78.14.128/28160.78.14.129 to 160.78.14.142160.78.14.14314
234160.78.14.144/28160.78.14.145 to 160.78.14.158160.78.14.15914
235160.78.14.160/28160.78.14.161 to 160.78.14.174160.78.14.17514
236160.78.14.176/28160.78.14.177 to 160.78.14.190160.78.14.19114
237160.78.14.192/28160.78.14.193 to 160.78.14.206160.78.14.20714
238160.78.14.208/28160.78.14.209 to 160.78.14.222160.78.14.22314
239160.78.14.224/28160.78.14.225 to 160.78.14.238160.78.14.23914
240160.78.14.240/28160.78.14.241 to 160.78.14.254160.78.14.25514
241160.78.15.0/28160.78.15.1 to 160.78.15.14160.78.15.1514
242160.78.15.16/28160.78.15.17 to 160.78.15.30160.78.15.3114
243160.78.15.32/28160.78.15.33 to 160.78.15.46160.78.15.4714
244160.78.15.48/28160.78.15.49 to 160.78.15.62160.78.15.6314
245160.78.15.64/28160.78.15.65 to 160.78.15.78160.78.15.7914
246160.78.15.80/28160.78.15.81 to 160.78.15.94160.78.15.9514
247160.78.15.96/28160.78.15.97 to 160.78.15.110160.78.15.11114
248160.78.15.112/28160.78.15.113 to 160.78.15.126160.78.15.12714
249160.78.15.128/28160.78.15.129 to 160.78.15.142160.78.15.14314
250160.78.15.144/28160.78.15.145 to 160.78.15.158160.78.15.15914
251160.78.15.160/28160.78.15.161 to 160.78.15.174160.78.15.17514
252160.78.15.176/28160.78.15.177 to 160.78.15.190160.78.15.19114
253160.78.15.192/28160.78.15.193 to 160.78.15.206160.78.15.20714
254160.78.15.208/28160.78.15.209 to 160.78.15.222160.78.15.22314
255160.78.15.224/28160.78.15.225 to 160.78.15.238160.78.15.23914
256160.78.15.240/28160.78.15.241 to 160.78.15.254160.78.15.25514

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.