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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.

Network176.64.0.0/10
Usable hosts4,194,302
Subnet mask255.192.0.0
Addresses4,194,304
Network address
176.64.0.0
Broadcast address
176.127.255.255
First usable
176.64.0.1
Last usable
176.127.255.254
Usable hosts
4,194,302 (4,194,304 less the network and broadcast addresses)
Subnet mask
255.192.0.0
Wildcard mask
0.63.255.255 (Cisco ACLs, OSPF)
Prefix length
/10
Type
Public public
Old class
B (default /16)
As numbers
Hex B0400000 · Integer 2956984320 to 2961178623
Reverse DNS zones
64.176.in-addr.arpa
65.176.in-addr.arpa
66.176.in-addr.arpa
67.176.in-addr.arpa
68.176.in-addr.arpa
69.176.in-addr.arpa
70.176.in-addr.arpa
71.176.in-addr.arpa
72.176.in-addr.arpa
73.176.in-addr.arpa
74.176.in-addr.arpa
75.176.in-addr.arpa
76.176.in-addr.arpa
77.176.in-addr.arpa
78.176.in-addr.arpa
79.176.in-addr.arpa
and 48 more
/10 is not on a 8-bit boundary, so it takes 64 /16 zones.
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address10110000.01000000.00000000.00000000176.64.0.0
Subnet mask11111111.11000000.00000000.00000000255.192.0.0
Network10110000.01000000.00000000.00000000176.64.0.0
Broadcast10110000.01111111.11111111.11111111176.127.255.255
Split into smaller subnets/22
/11 (2)/12 (4)/13 (8)/14 (16)/15 (32)/16 (64)/17 (128)/18 (256)/19 (512)/20 (1,024)/21 (2,048)/22 (4,096)

176.64.0.0/10 makes 4,096 subnets of /22; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
1176.64.0.0/22176.64.0.1 to 176.64.3.254176.64.3.2551,022
2176.64.4.0/22176.64.4.1 to 176.64.7.254176.64.7.2551,022
3176.64.8.0/22176.64.8.1 to 176.64.11.254176.64.11.2551,022
4176.64.12.0/22176.64.12.1 to 176.64.15.254176.64.15.2551,022
5176.64.16.0/22176.64.16.1 to 176.64.19.254176.64.19.2551,022
6176.64.20.0/22176.64.20.1 to 176.64.23.254176.64.23.2551,022
7176.64.24.0/22176.64.24.1 to 176.64.27.254176.64.27.2551,022
8176.64.28.0/22176.64.28.1 to 176.64.31.254176.64.31.2551,022
9176.64.32.0/22176.64.32.1 to 176.64.35.254176.64.35.2551,022
10176.64.36.0/22176.64.36.1 to 176.64.39.254176.64.39.2551,022
11176.64.40.0/22176.64.40.1 to 176.64.43.254176.64.43.2551,022
12176.64.44.0/22176.64.44.1 to 176.64.47.254176.64.47.2551,022
13176.64.48.0/22176.64.48.1 to 176.64.51.254176.64.51.2551,022
14176.64.52.0/22176.64.52.1 to 176.64.55.254176.64.55.2551,022
15176.64.56.0/22176.64.56.1 to 176.64.59.254176.64.59.2551,022
16176.64.60.0/22176.64.60.1 to 176.64.63.254176.64.63.2551,022
17176.64.64.0/22176.64.64.1 to 176.64.67.254176.64.67.2551,022
18176.64.68.0/22176.64.68.1 to 176.64.71.254176.64.71.2551,022
19176.64.72.0/22176.64.72.1 to 176.64.75.254176.64.75.2551,022
20176.64.76.0/22176.64.76.1 to 176.64.79.254176.64.79.2551,022
21176.64.80.0/22176.64.80.1 to 176.64.83.254176.64.83.2551,022
22176.64.84.0/22176.64.84.1 to 176.64.87.254176.64.87.2551,022
23176.64.88.0/22176.64.88.1 to 176.64.91.254176.64.91.2551,022
24176.64.92.0/22176.64.92.1 to 176.64.95.254176.64.95.2551,022
25176.64.96.0/22176.64.96.1 to 176.64.99.254176.64.99.2551,022
26176.64.100.0/22176.64.100.1 to 176.64.103.254176.64.103.2551,022
27176.64.104.0/22176.64.104.1 to 176.64.107.254176.64.107.2551,022
28176.64.108.0/22176.64.108.1 to 176.64.111.254176.64.111.2551,022
29176.64.112.0/22176.64.112.1 to 176.64.115.254176.64.115.2551,022
30176.64.116.0/22176.64.116.1 to 176.64.119.254176.64.119.2551,022
31176.64.120.0/22176.64.120.1 to 176.64.123.254176.64.123.2551,022
32176.64.124.0/22176.64.124.1 to 176.64.127.254176.64.127.2551,022
33176.64.128.0/22176.64.128.1 to 176.64.131.254176.64.131.2551,022
34176.64.132.0/22176.64.132.1 to 176.64.135.254176.64.135.2551,022
35176.64.136.0/22176.64.136.1 to 176.64.139.254176.64.139.2551,022
36176.64.140.0/22176.64.140.1 to 176.64.143.254176.64.143.2551,022
37176.64.144.0/22176.64.144.1 to 176.64.147.254176.64.147.2551,022
38176.64.148.0/22176.64.148.1 to 176.64.151.254176.64.151.2551,022
39176.64.152.0/22176.64.152.1 to 176.64.155.254176.64.155.2551,022
40176.64.156.0/22176.64.156.1 to 176.64.159.254176.64.159.2551,022
41176.64.160.0/22176.64.160.1 to 176.64.163.254176.64.163.2551,022
42176.64.164.0/22176.64.164.1 to 176.64.167.254176.64.167.2551,022
43176.64.168.0/22176.64.168.1 to 176.64.171.254176.64.171.2551,022
44176.64.172.0/22176.64.172.1 to 176.64.175.254176.64.175.2551,022
45176.64.176.0/22176.64.176.1 to 176.64.179.254176.64.179.2551,022
46176.64.180.0/22176.64.180.1 to 176.64.183.254176.64.183.2551,022
47176.64.184.0/22176.64.184.1 to 176.64.187.254176.64.187.2551,022
48176.64.188.0/22176.64.188.1 to 176.64.191.254176.64.191.2551,022
49176.64.192.0/22176.64.192.1 to 176.64.195.254176.64.195.2551,022
50176.64.196.0/22176.64.196.1 to 176.64.199.254176.64.199.2551,022
51176.64.200.0/22176.64.200.1 to 176.64.203.254176.64.203.2551,022
52176.64.204.0/22176.64.204.1 to 176.64.207.254176.64.207.2551,022
53176.64.208.0/22176.64.208.1 to 176.64.211.254176.64.211.2551,022
54176.64.212.0/22176.64.212.1 to 176.64.215.254176.64.215.2551,022
55176.64.216.0/22176.64.216.1 to 176.64.219.254176.64.219.2551,022
56176.64.220.0/22176.64.220.1 to 176.64.223.254176.64.223.2551,022
57176.64.224.0/22176.64.224.1 to 176.64.227.254176.64.227.2551,022
58176.64.228.0/22176.64.228.1 to 176.64.231.254176.64.231.2551,022
59176.64.232.0/22176.64.232.1 to 176.64.235.254176.64.235.2551,022
60176.64.236.0/22176.64.236.1 to 176.64.239.254176.64.239.2551,022
61176.64.240.0/22176.64.240.1 to 176.64.243.254176.64.243.2551,022
62176.64.244.0/22176.64.244.1 to 176.64.247.254176.64.247.2551,022
63176.64.248.0/22176.64.248.1 to 176.64.251.254176.64.251.2551,022
64176.64.252.0/22176.64.252.1 to 176.64.255.254176.64.255.2551,022
65176.65.0.0/22176.65.0.1 to 176.65.3.254176.65.3.2551,022
66176.65.4.0/22176.65.4.1 to 176.65.7.254176.65.7.2551,022
67176.65.8.0/22176.65.8.1 to 176.65.11.254176.65.11.2551,022
68176.65.12.0/22176.65.12.1 to 176.65.15.254176.65.15.2551,022
69176.65.16.0/22176.65.16.1 to 176.65.19.254176.65.19.2551,022
70176.65.20.0/22176.65.20.1 to 176.65.23.254176.65.23.2551,022
71176.65.24.0/22176.65.24.1 to 176.65.27.254176.65.27.2551,022
72176.65.28.0/22176.65.28.1 to 176.65.31.254176.65.31.2551,022
73176.65.32.0/22176.65.32.1 to 176.65.35.254176.65.35.2551,022
74176.65.36.0/22176.65.36.1 to 176.65.39.254176.65.39.2551,022
75176.65.40.0/22176.65.40.1 to 176.65.43.254176.65.43.2551,022
76176.65.44.0/22176.65.44.1 to 176.65.47.254176.65.47.2551,022
77176.65.48.0/22176.65.48.1 to 176.65.51.254176.65.51.2551,022
78176.65.52.0/22176.65.52.1 to 176.65.55.254176.65.55.2551,022
79176.65.56.0/22176.65.56.1 to 176.65.59.254176.65.59.2551,022
80176.65.60.0/22176.65.60.1 to 176.65.63.254176.65.63.2551,022
81176.65.64.0/22176.65.64.1 to 176.65.67.254176.65.67.2551,022
82176.65.68.0/22176.65.68.1 to 176.65.71.254176.65.71.2551,022
83176.65.72.0/22176.65.72.1 to 176.65.75.254176.65.75.2551,022
84176.65.76.0/22176.65.76.1 to 176.65.79.254176.65.79.2551,022
85176.65.80.0/22176.65.80.1 to 176.65.83.254176.65.83.2551,022
86176.65.84.0/22176.65.84.1 to 176.65.87.254176.65.87.2551,022
87176.65.88.0/22176.65.88.1 to 176.65.91.254176.65.91.2551,022
88176.65.92.0/22176.65.92.1 to 176.65.95.254176.65.95.2551,022
89176.65.96.0/22176.65.96.1 to 176.65.99.254176.65.99.2551,022
90176.65.100.0/22176.65.100.1 to 176.65.103.254176.65.103.2551,022
91176.65.104.0/22176.65.104.1 to 176.65.107.254176.65.107.2551,022
92176.65.108.0/22176.65.108.1 to 176.65.111.254176.65.111.2551,022
93176.65.112.0/22176.65.112.1 to 176.65.115.254176.65.115.2551,022
94176.65.116.0/22176.65.116.1 to 176.65.119.254176.65.119.2551,022
95176.65.120.0/22176.65.120.1 to 176.65.123.254176.65.123.2551,022
96176.65.124.0/22176.65.124.1 to 176.65.127.254176.65.127.2551,022
97176.65.128.0/22176.65.128.1 to 176.65.131.254176.65.131.2551,022
98176.65.132.0/22176.65.132.1 to 176.65.135.254176.65.135.2551,022
99176.65.136.0/22176.65.136.1 to 176.65.139.254176.65.139.2551,022
100176.65.140.0/22176.65.140.1 to 176.65.143.254176.65.143.2551,022
101176.65.144.0/22176.65.144.1 to 176.65.147.254176.65.147.2551,022
102176.65.148.0/22176.65.148.1 to 176.65.151.254176.65.151.2551,022
103176.65.152.0/22176.65.152.1 to 176.65.155.254176.65.155.2551,022
104176.65.156.0/22176.65.156.1 to 176.65.159.254176.65.159.2551,022
105176.65.160.0/22176.65.160.1 to 176.65.163.254176.65.163.2551,022
106176.65.164.0/22176.65.164.1 to 176.65.167.254176.65.167.2551,022
107176.65.168.0/22176.65.168.1 to 176.65.171.254176.65.171.2551,022
108176.65.172.0/22176.65.172.1 to 176.65.175.254176.65.175.2551,022
109176.65.176.0/22176.65.176.1 to 176.65.179.254176.65.179.2551,022
110176.65.180.0/22176.65.180.1 to 176.65.183.254176.65.183.2551,022
111176.65.184.0/22176.65.184.1 to 176.65.187.254176.65.187.2551,022
112176.65.188.0/22176.65.188.1 to 176.65.191.254176.65.191.2551,022
113176.65.192.0/22176.65.192.1 to 176.65.195.254176.65.195.2551,022
114176.65.196.0/22176.65.196.1 to 176.65.199.254176.65.199.2551,022
115176.65.200.0/22176.65.200.1 to 176.65.203.254176.65.203.2551,022
116176.65.204.0/22176.65.204.1 to 176.65.207.254176.65.207.2551,022
117176.65.208.0/22176.65.208.1 to 176.65.211.254176.65.211.2551,022
118176.65.212.0/22176.65.212.1 to 176.65.215.254176.65.215.2551,022
119176.65.216.0/22176.65.216.1 to 176.65.219.254176.65.219.2551,022
120176.65.220.0/22176.65.220.1 to 176.65.223.254176.65.223.2551,022
121176.65.224.0/22176.65.224.1 to 176.65.227.254176.65.227.2551,022
122176.65.228.0/22176.65.228.1 to 176.65.231.254176.65.231.2551,022
123176.65.232.0/22176.65.232.1 to 176.65.235.254176.65.235.2551,022
124176.65.236.0/22176.65.236.1 to 176.65.239.254176.65.239.2551,022
125176.65.240.0/22176.65.240.1 to 176.65.243.254176.65.243.2551,022
126176.65.244.0/22176.65.244.1 to 176.65.247.254176.65.247.2551,022
127176.65.248.0/22176.65.248.1 to 176.65.251.254176.65.251.2551,022
128176.65.252.0/22176.65.252.1 to 176.65.255.254176.65.255.2551,022
129176.66.0.0/22176.66.0.1 to 176.66.3.254176.66.3.2551,022
130176.66.4.0/22176.66.4.1 to 176.66.7.254176.66.7.2551,022
131176.66.8.0/22176.66.8.1 to 176.66.11.254176.66.11.2551,022
132176.66.12.0/22176.66.12.1 to 176.66.15.254176.66.15.2551,022
133176.66.16.0/22176.66.16.1 to 176.66.19.254176.66.19.2551,022
134176.66.20.0/22176.66.20.1 to 176.66.23.254176.66.23.2551,022
135176.66.24.0/22176.66.24.1 to 176.66.27.254176.66.27.2551,022
136176.66.28.0/22176.66.28.1 to 176.66.31.254176.66.31.2551,022
137176.66.32.0/22176.66.32.1 to 176.66.35.254176.66.35.2551,022
138176.66.36.0/22176.66.36.1 to 176.66.39.254176.66.39.2551,022
139176.66.40.0/22176.66.40.1 to 176.66.43.254176.66.43.2551,022
140176.66.44.0/22176.66.44.1 to 176.66.47.254176.66.47.2551,022
141176.66.48.0/22176.66.48.1 to 176.66.51.254176.66.51.2551,022
142176.66.52.0/22176.66.52.1 to 176.66.55.254176.66.55.2551,022
143176.66.56.0/22176.66.56.1 to 176.66.59.254176.66.59.2551,022
144176.66.60.0/22176.66.60.1 to 176.66.63.254176.66.63.2551,022
145176.66.64.0/22176.66.64.1 to 176.66.67.254176.66.67.2551,022
146176.66.68.0/22176.66.68.1 to 176.66.71.254176.66.71.2551,022
147176.66.72.0/22176.66.72.1 to 176.66.75.254176.66.75.2551,022
148176.66.76.0/22176.66.76.1 to 176.66.79.254176.66.79.2551,022
149176.66.80.0/22176.66.80.1 to 176.66.83.254176.66.83.2551,022
150176.66.84.0/22176.66.84.1 to 176.66.87.254176.66.87.2551,022
151176.66.88.0/22176.66.88.1 to 176.66.91.254176.66.91.2551,022
152176.66.92.0/22176.66.92.1 to 176.66.95.254176.66.95.2551,022
153176.66.96.0/22176.66.96.1 to 176.66.99.254176.66.99.2551,022
154176.66.100.0/22176.66.100.1 to 176.66.103.254176.66.103.2551,022
155176.66.104.0/22176.66.104.1 to 176.66.107.254176.66.107.2551,022
156176.66.108.0/22176.66.108.1 to 176.66.111.254176.66.111.2551,022
157176.66.112.0/22176.66.112.1 to 176.66.115.254176.66.115.2551,022
158176.66.116.0/22176.66.116.1 to 176.66.119.254176.66.119.2551,022
159176.66.120.0/22176.66.120.1 to 176.66.123.254176.66.123.2551,022
160176.66.124.0/22176.66.124.1 to 176.66.127.254176.66.127.2551,022
161176.66.128.0/22176.66.128.1 to 176.66.131.254176.66.131.2551,022
162176.66.132.0/22176.66.132.1 to 176.66.135.254176.66.135.2551,022
163176.66.136.0/22176.66.136.1 to 176.66.139.254176.66.139.2551,022
164176.66.140.0/22176.66.140.1 to 176.66.143.254176.66.143.2551,022
165176.66.144.0/22176.66.144.1 to 176.66.147.254176.66.147.2551,022
166176.66.148.0/22176.66.148.1 to 176.66.151.254176.66.151.2551,022
167176.66.152.0/22176.66.152.1 to 176.66.155.254176.66.155.2551,022
168176.66.156.0/22176.66.156.1 to 176.66.159.254176.66.159.2551,022
169176.66.160.0/22176.66.160.1 to 176.66.163.254176.66.163.2551,022
170176.66.164.0/22176.66.164.1 to 176.66.167.254176.66.167.2551,022
171176.66.168.0/22176.66.168.1 to 176.66.171.254176.66.171.2551,022
172176.66.172.0/22176.66.172.1 to 176.66.175.254176.66.175.2551,022
173176.66.176.0/22176.66.176.1 to 176.66.179.254176.66.179.2551,022
174176.66.180.0/22176.66.180.1 to 176.66.183.254176.66.183.2551,022
175176.66.184.0/22176.66.184.1 to 176.66.187.254176.66.187.2551,022
176176.66.188.0/22176.66.188.1 to 176.66.191.254176.66.191.2551,022
177176.66.192.0/22176.66.192.1 to 176.66.195.254176.66.195.2551,022
178176.66.196.0/22176.66.196.1 to 176.66.199.254176.66.199.2551,022
179176.66.200.0/22176.66.200.1 to 176.66.203.254176.66.203.2551,022
180176.66.204.0/22176.66.204.1 to 176.66.207.254176.66.207.2551,022
181176.66.208.0/22176.66.208.1 to 176.66.211.254176.66.211.2551,022
182176.66.212.0/22176.66.212.1 to 176.66.215.254176.66.215.2551,022
183176.66.216.0/22176.66.216.1 to 176.66.219.254176.66.219.2551,022
184176.66.220.0/22176.66.220.1 to 176.66.223.254176.66.223.2551,022
185176.66.224.0/22176.66.224.1 to 176.66.227.254176.66.227.2551,022
186176.66.228.0/22176.66.228.1 to 176.66.231.254176.66.231.2551,022
187176.66.232.0/22176.66.232.1 to 176.66.235.254176.66.235.2551,022
188176.66.236.0/22176.66.236.1 to 176.66.239.254176.66.239.2551,022
189176.66.240.0/22176.66.240.1 to 176.66.243.254176.66.243.2551,022
190176.66.244.0/22176.66.244.1 to 176.66.247.254176.66.247.2551,022
191176.66.248.0/22176.66.248.1 to 176.66.251.254176.66.251.2551,022
192176.66.252.0/22176.66.252.1 to 176.66.255.254176.66.255.2551,022
193176.67.0.0/22176.67.0.1 to 176.67.3.254176.67.3.2551,022
194176.67.4.0/22176.67.4.1 to 176.67.7.254176.67.7.2551,022
195176.67.8.0/22176.67.8.1 to 176.67.11.254176.67.11.2551,022
196176.67.12.0/22176.67.12.1 to 176.67.15.254176.67.15.2551,022
197176.67.16.0/22176.67.16.1 to 176.67.19.254176.67.19.2551,022
198176.67.20.0/22176.67.20.1 to 176.67.23.254176.67.23.2551,022
199176.67.24.0/22176.67.24.1 to 176.67.27.254176.67.27.2551,022
200176.67.28.0/22176.67.28.1 to 176.67.31.254176.67.31.2551,022
201176.67.32.0/22176.67.32.1 to 176.67.35.254176.67.35.2551,022
202176.67.36.0/22176.67.36.1 to 176.67.39.254176.67.39.2551,022
203176.67.40.0/22176.67.40.1 to 176.67.43.254176.67.43.2551,022
204176.67.44.0/22176.67.44.1 to 176.67.47.254176.67.47.2551,022
205176.67.48.0/22176.67.48.1 to 176.67.51.254176.67.51.2551,022
206176.67.52.0/22176.67.52.1 to 176.67.55.254176.67.55.2551,022
207176.67.56.0/22176.67.56.1 to 176.67.59.254176.67.59.2551,022
208176.67.60.0/22176.67.60.1 to 176.67.63.254176.67.63.2551,022
209176.67.64.0/22176.67.64.1 to 176.67.67.254176.67.67.2551,022
210176.67.68.0/22176.67.68.1 to 176.67.71.254176.67.71.2551,022
211176.67.72.0/22176.67.72.1 to 176.67.75.254176.67.75.2551,022
212176.67.76.0/22176.67.76.1 to 176.67.79.254176.67.79.2551,022
213176.67.80.0/22176.67.80.1 to 176.67.83.254176.67.83.2551,022
214176.67.84.0/22176.67.84.1 to 176.67.87.254176.67.87.2551,022
215176.67.88.0/22176.67.88.1 to 176.67.91.254176.67.91.2551,022
216176.67.92.0/22176.67.92.1 to 176.67.95.254176.67.95.2551,022
217176.67.96.0/22176.67.96.1 to 176.67.99.254176.67.99.2551,022
218176.67.100.0/22176.67.100.1 to 176.67.103.254176.67.103.2551,022
219176.67.104.0/22176.67.104.1 to 176.67.107.254176.67.107.2551,022
220176.67.108.0/22176.67.108.1 to 176.67.111.254176.67.111.2551,022
221176.67.112.0/22176.67.112.1 to 176.67.115.254176.67.115.2551,022
222176.67.116.0/22176.67.116.1 to 176.67.119.254176.67.119.2551,022
223176.67.120.0/22176.67.120.1 to 176.67.123.254176.67.123.2551,022
224176.67.124.0/22176.67.124.1 to 176.67.127.254176.67.127.2551,022
225176.67.128.0/22176.67.128.1 to 176.67.131.254176.67.131.2551,022
226176.67.132.0/22176.67.132.1 to 176.67.135.254176.67.135.2551,022
227176.67.136.0/22176.67.136.1 to 176.67.139.254176.67.139.2551,022
228176.67.140.0/22176.67.140.1 to 176.67.143.254176.67.143.2551,022
229176.67.144.0/22176.67.144.1 to 176.67.147.254176.67.147.2551,022
230176.67.148.0/22176.67.148.1 to 176.67.151.254176.67.151.2551,022
231176.67.152.0/22176.67.152.1 to 176.67.155.254176.67.155.2551,022
232176.67.156.0/22176.67.156.1 to 176.67.159.254176.67.159.2551,022
233176.67.160.0/22176.67.160.1 to 176.67.163.254176.67.163.2551,022
234176.67.164.0/22176.67.164.1 to 176.67.167.254176.67.167.2551,022
235176.67.168.0/22176.67.168.1 to 176.67.171.254176.67.171.2551,022
236176.67.172.0/22176.67.172.1 to 176.67.175.254176.67.175.2551,022
237176.67.176.0/22176.67.176.1 to 176.67.179.254176.67.179.2551,022
238176.67.180.0/22176.67.180.1 to 176.67.183.254176.67.183.2551,022
239176.67.184.0/22176.67.184.1 to 176.67.187.254176.67.187.2551,022
240176.67.188.0/22176.67.188.1 to 176.67.191.254176.67.191.2551,022
241176.67.192.0/22176.67.192.1 to 176.67.195.254176.67.195.2551,022
242176.67.196.0/22176.67.196.1 to 176.67.199.254176.67.199.2551,022
243176.67.200.0/22176.67.200.1 to 176.67.203.254176.67.203.2551,022
244176.67.204.0/22176.67.204.1 to 176.67.207.254176.67.207.2551,022
245176.67.208.0/22176.67.208.1 to 176.67.211.254176.67.211.2551,022
246176.67.212.0/22176.67.212.1 to 176.67.215.254176.67.215.2551,022
247176.67.216.0/22176.67.216.1 to 176.67.219.254176.67.219.2551,022
248176.67.220.0/22176.67.220.1 to 176.67.223.254176.67.223.2551,022
249176.67.224.0/22176.67.224.1 to 176.67.227.254176.67.227.2551,022
250176.67.228.0/22176.67.228.1 to 176.67.231.254176.67.231.2551,022
251176.67.232.0/22176.67.232.1 to 176.67.235.254176.67.235.2551,022
252176.67.236.0/22176.67.236.1 to 176.67.239.254176.67.239.2551,022
253176.67.240.0/22176.67.240.1 to 176.67.243.254176.67.243.2551,022
254176.67.244.0/22176.67.244.1 to 176.67.247.254176.67.247.2551,022
255176.67.248.0/22176.67.248.1 to 176.67.251.254176.67.251.2551,022
256176.67.252.0/22176.67.252.1 to 176.67.255.254176.67.255.2551,022

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.