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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.

Network201.192.0.0/10
Usable hosts4,194,302
Subnet mask255.192.0.0
Addresses4,194,304
Network address
201.192.0.0
Broadcast address
201.255.255.255
First usable
201.192.0.1
Last usable
201.255.255.254
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
C (default /24)
As numbers
Hex C9C00000 · Integer 3384803328 to 3388997631
Reverse DNS zones
192.201.in-addr.arpa
193.201.in-addr.arpa
194.201.in-addr.arpa
195.201.in-addr.arpa
196.201.in-addr.arpa
197.201.in-addr.arpa
198.201.in-addr.arpa
199.201.in-addr.arpa
200.201.in-addr.arpa
201.201.in-addr.arpa
202.201.in-addr.arpa
203.201.in-addr.arpa
204.201.in-addr.arpa
205.201.in-addr.arpa
206.201.in-addr.arpa
207.201.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
Address11001001.11000000.00000000.00000000201.192.0.0
Subnet mask11111111.11000000.00000000.00000000255.192.0.0
Network11001001.11000000.00000000.00000000201.192.0.0
Broadcast11001001.11111111.11111111.11111111201.255.255.255
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)

201.192.0.0/10 makes 4,096 subnets of /22; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
1201.192.0.0/22201.192.0.1 to 201.192.3.254201.192.3.2551,022
2201.192.4.0/22201.192.4.1 to 201.192.7.254201.192.7.2551,022
3201.192.8.0/22201.192.8.1 to 201.192.11.254201.192.11.2551,022
4201.192.12.0/22201.192.12.1 to 201.192.15.254201.192.15.2551,022
5201.192.16.0/22201.192.16.1 to 201.192.19.254201.192.19.2551,022
6201.192.20.0/22201.192.20.1 to 201.192.23.254201.192.23.2551,022
7201.192.24.0/22201.192.24.1 to 201.192.27.254201.192.27.2551,022
8201.192.28.0/22201.192.28.1 to 201.192.31.254201.192.31.2551,022
9201.192.32.0/22201.192.32.1 to 201.192.35.254201.192.35.2551,022
10201.192.36.0/22201.192.36.1 to 201.192.39.254201.192.39.2551,022
11201.192.40.0/22201.192.40.1 to 201.192.43.254201.192.43.2551,022
12201.192.44.0/22201.192.44.1 to 201.192.47.254201.192.47.2551,022
13201.192.48.0/22201.192.48.1 to 201.192.51.254201.192.51.2551,022
14201.192.52.0/22201.192.52.1 to 201.192.55.254201.192.55.2551,022
15201.192.56.0/22201.192.56.1 to 201.192.59.254201.192.59.2551,022
16201.192.60.0/22201.192.60.1 to 201.192.63.254201.192.63.2551,022
17201.192.64.0/22201.192.64.1 to 201.192.67.254201.192.67.2551,022
18201.192.68.0/22201.192.68.1 to 201.192.71.254201.192.71.2551,022
19201.192.72.0/22201.192.72.1 to 201.192.75.254201.192.75.2551,022
20201.192.76.0/22201.192.76.1 to 201.192.79.254201.192.79.2551,022
21201.192.80.0/22201.192.80.1 to 201.192.83.254201.192.83.2551,022
22201.192.84.0/22201.192.84.1 to 201.192.87.254201.192.87.2551,022
23201.192.88.0/22201.192.88.1 to 201.192.91.254201.192.91.2551,022
24201.192.92.0/22201.192.92.1 to 201.192.95.254201.192.95.2551,022
25201.192.96.0/22201.192.96.1 to 201.192.99.254201.192.99.2551,022
26201.192.100.0/22201.192.100.1 to 201.192.103.254201.192.103.2551,022
27201.192.104.0/22201.192.104.1 to 201.192.107.254201.192.107.2551,022
28201.192.108.0/22201.192.108.1 to 201.192.111.254201.192.111.2551,022
29201.192.112.0/22201.192.112.1 to 201.192.115.254201.192.115.2551,022
30201.192.116.0/22201.192.116.1 to 201.192.119.254201.192.119.2551,022
31201.192.120.0/22201.192.120.1 to 201.192.123.254201.192.123.2551,022
32201.192.124.0/22201.192.124.1 to 201.192.127.254201.192.127.2551,022
33201.192.128.0/22201.192.128.1 to 201.192.131.254201.192.131.2551,022
34201.192.132.0/22201.192.132.1 to 201.192.135.254201.192.135.2551,022
35201.192.136.0/22201.192.136.1 to 201.192.139.254201.192.139.2551,022
36201.192.140.0/22201.192.140.1 to 201.192.143.254201.192.143.2551,022
37201.192.144.0/22201.192.144.1 to 201.192.147.254201.192.147.2551,022
38201.192.148.0/22201.192.148.1 to 201.192.151.254201.192.151.2551,022
39201.192.152.0/22201.192.152.1 to 201.192.155.254201.192.155.2551,022
40201.192.156.0/22201.192.156.1 to 201.192.159.254201.192.159.2551,022
41201.192.160.0/22201.192.160.1 to 201.192.163.254201.192.163.2551,022
42201.192.164.0/22201.192.164.1 to 201.192.167.254201.192.167.2551,022
43201.192.168.0/22201.192.168.1 to 201.192.171.254201.192.171.2551,022
44201.192.172.0/22201.192.172.1 to 201.192.175.254201.192.175.2551,022
45201.192.176.0/22201.192.176.1 to 201.192.179.254201.192.179.2551,022
46201.192.180.0/22201.192.180.1 to 201.192.183.254201.192.183.2551,022
47201.192.184.0/22201.192.184.1 to 201.192.187.254201.192.187.2551,022
48201.192.188.0/22201.192.188.1 to 201.192.191.254201.192.191.2551,022
49201.192.192.0/22201.192.192.1 to 201.192.195.254201.192.195.2551,022
50201.192.196.0/22201.192.196.1 to 201.192.199.254201.192.199.2551,022
51201.192.200.0/22201.192.200.1 to 201.192.203.254201.192.203.2551,022
52201.192.204.0/22201.192.204.1 to 201.192.207.254201.192.207.2551,022
53201.192.208.0/22201.192.208.1 to 201.192.211.254201.192.211.2551,022
54201.192.212.0/22201.192.212.1 to 201.192.215.254201.192.215.2551,022
55201.192.216.0/22201.192.216.1 to 201.192.219.254201.192.219.2551,022
56201.192.220.0/22201.192.220.1 to 201.192.223.254201.192.223.2551,022
57201.192.224.0/22201.192.224.1 to 201.192.227.254201.192.227.2551,022
58201.192.228.0/22201.192.228.1 to 201.192.231.254201.192.231.2551,022
59201.192.232.0/22201.192.232.1 to 201.192.235.254201.192.235.2551,022
60201.192.236.0/22201.192.236.1 to 201.192.239.254201.192.239.2551,022
61201.192.240.0/22201.192.240.1 to 201.192.243.254201.192.243.2551,022
62201.192.244.0/22201.192.244.1 to 201.192.247.254201.192.247.2551,022
63201.192.248.0/22201.192.248.1 to 201.192.251.254201.192.251.2551,022
64201.192.252.0/22201.192.252.1 to 201.192.255.254201.192.255.2551,022
65201.193.0.0/22201.193.0.1 to 201.193.3.254201.193.3.2551,022
66201.193.4.0/22201.193.4.1 to 201.193.7.254201.193.7.2551,022
67201.193.8.0/22201.193.8.1 to 201.193.11.254201.193.11.2551,022
68201.193.12.0/22201.193.12.1 to 201.193.15.254201.193.15.2551,022
69201.193.16.0/22201.193.16.1 to 201.193.19.254201.193.19.2551,022
70201.193.20.0/22201.193.20.1 to 201.193.23.254201.193.23.2551,022
71201.193.24.0/22201.193.24.1 to 201.193.27.254201.193.27.2551,022
72201.193.28.0/22201.193.28.1 to 201.193.31.254201.193.31.2551,022
73201.193.32.0/22201.193.32.1 to 201.193.35.254201.193.35.2551,022
74201.193.36.0/22201.193.36.1 to 201.193.39.254201.193.39.2551,022
75201.193.40.0/22201.193.40.1 to 201.193.43.254201.193.43.2551,022
76201.193.44.0/22201.193.44.1 to 201.193.47.254201.193.47.2551,022
77201.193.48.0/22201.193.48.1 to 201.193.51.254201.193.51.2551,022
78201.193.52.0/22201.193.52.1 to 201.193.55.254201.193.55.2551,022
79201.193.56.0/22201.193.56.1 to 201.193.59.254201.193.59.2551,022
80201.193.60.0/22201.193.60.1 to 201.193.63.254201.193.63.2551,022
81201.193.64.0/22201.193.64.1 to 201.193.67.254201.193.67.2551,022
82201.193.68.0/22201.193.68.1 to 201.193.71.254201.193.71.2551,022
83201.193.72.0/22201.193.72.1 to 201.193.75.254201.193.75.2551,022
84201.193.76.0/22201.193.76.1 to 201.193.79.254201.193.79.2551,022
85201.193.80.0/22201.193.80.1 to 201.193.83.254201.193.83.2551,022
86201.193.84.0/22201.193.84.1 to 201.193.87.254201.193.87.2551,022
87201.193.88.0/22201.193.88.1 to 201.193.91.254201.193.91.2551,022
88201.193.92.0/22201.193.92.1 to 201.193.95.254201.193.95.2551,022
89201.193.96.0/22201.193.96.1 to 201.193.99.254201.193.99.2551,022
90201.193.100.0/22201.193.100.1 to 201.193.103.254201.193.103.2551,022
91201.193.104.0/22201.193.104.1 to 201.193.107.254201.193.107.2551,022
92201.193.108.0/22201.193.108.1 to 201.193.111.254201.193.111.2551,022
93201.193.112.0/22201.193.112.1 to 201.193.115.254201.193.115.2551,022
94201.193.116.0/22201.193.116.1 to 201.193.119.254201.193.119.2551,022
95201.193.120.0/22201.193.120.1 to 201.193.123.254201.193.123.2551,022
96201.193.124.0/22201.193.124.1 to 201.193.127.254201.193.127.2551,022
97201.193.128.0/22201.193.128.1 to 201.193.131.254201.193.131.2551,022
98201.193.132.0/22201.193.132.1 to 201.193.135.254201.193.135.2551,022
99201.193.136.0/22201.193.136.1 to 201.193.139.254201.193.139.2551,022
100201.193.140.0/22201.193.140.1 to 201.193.143.254201.193.143.2551,022
101201.193.144.0/22201.193.144.1 to 201.193.147.254201.193.147.2551,022
102201.193.148.0/22201.193.148.1 to 201.193.151.254201.193.151.2551,022
103201.193.152.0/22201.193.152.1 to 201.193.155.254201.193.155.2551,022
104201.193.156.0/22201.193.156.1 to 201.193.159.254201.193.159.2551,022
105201.193.160.0/22201.193.160.1 to 201.193.163.254201.193.163.2551,022
106201.193.164.0/22201.193.164.1 to 201.193.167.254201.193.167.2551,022
107201.193.168.0/22201.193.168.1 to 201.193.171.254201.193.171.2551,022
108201.193.172.0/22201.193.172.1 to 201.193.175.254201.193.175.2551,022
109201.193.176.0/22201.193.176.1 to 201.193.179.254201.193.179.2551,022
110201.193.180.0/22201.193.180.1 to 201.193.183.254201.193.183.2551,022
111201.193.184.0/22201.193.184.1 to 201.193.187.254201.193.187.2551,022
112201.193.188.0/22201.193.188.1 to 201.193.191.254201.193.191.2551,022
113201.193.192.0/22201.193.192.1 to 201.193.195.254201.193.195.2551,022
114201.193.196.0/22201.193.196.1 to 201.193.199.254201.193.199.2551,022
115201.193.200.0/22201.193.200.1 to 201.193.203.254201.193.203.2551,022
116201.193.204.0/22201.193.204.1 to 201.193.207.254201.193.207.2551,022
117201.193.208.0/22201.193.208.1 to 201.193.211.254201.193.211.2551,022
118201.193.212.0/22201.193.212.1 to 201.193.215.254201.193.215.2551,022
119201.193.216.0/22201.193.216.1 to 201.193.219.254201.193.219.2551,022
120201.193.220.0/22201.193.220.1 to 201.193.223.254201.193.223.2551,022
121201.193.224.0/22201.193.224.1 to 201.193.227.254201.193.227.2551,022
122201.193.228.0/22201.193.228.1 to 201.193.231.254201.193.231.2551,022
123201.193.232.0/22201.193.232.1 to 201.193.235.254201.193.235.2551,022
124201.193.236.0/22201.193.236.1 to 201.193.239.254201.193.239.2551,022
125201.193.240.0/22201.193.240.1 to 201.193.243.254201.193.243.2551,022
126201.193.244.0/22201.193.244.1 to 201.193.247.254201.193.247.2551,022
127201.193.248.0/22201.193.248.1 to 201.193.251.254201.193.251.2551,022
128201.193.252.0/22201.193.252.1 to 201.193.255.254201.193.255.2551,022
129201.194.0.0/22201.194.0.1 to 201.194.3.254201.194.3.2551,022
130201.194.4.0/22201.194.4.1 to 201.194.7.254201.194.7.2551,022
131201.194.8.0/22201.194.8.1 to 201.194.11.254201.194.11.2551,022
132201.194.12.0/22201.194.12.1 to 201.194.15.254201.194.15.2551,022
133201.194.16.0/22201.194.16.1 to 201.194.19.254201.194.19.2551,022
134201.194.20.0/22201.194.20.1 to 201.194.23.254201.194.23.2551,022
135201.194.24.0/22201.194.24.1 to 201.194.27.254201.194.27.2551,022
136201.194.28.0/22201.194.28.1 to 201.194.31.254201.194.31.2551,022
137201.194.32.0/22201.194.32.1 to 201.194.35.254201.194.35.2551,022
138201.194.36.0/22201.194.36.1 to 201.194.39.254201.194.39.2551,022
139201.194.40.0/22201.194.40.1 to 201.194.43.254201.194.43.2551,022
140201.194.44.0/22201.194.44.1 to 201.194.47.254201.194.47.2551,022
141201.194.48.0/22201.194.48.1 to 201.194.51.254201.194.51.2551,022
142201.194.52.0/22201.194.52.1 to 201.194.55.254201.194.55.2551,022
143201.194.56.0/22201.194.56.1 to 201.194.59.254201.194.59.2551,022
144201.194.60.0/22201.194.60.1 to 201.194.63.254201.194.63.2551,022
145201.194.64.0/22201.194.64.1 to 201.194.67.254201.194.67.2551,022
146201.194.68.0/22201.194.68.1 to 201.194.71.254201.194.71.2551,022
147201.194.72.0/22201.194.72.1 to 201.194.75.254201.194.75.2551,022
148201.194.76.0/22201.194.76.1 to 201.194.79.254201.194.79.2551,022
149201.194.80.0/22201.194.80.1 to 201.194.83.254201.194.83.2551,022
150201.194.84.0/22201.194.84.1 to 201.194.87.254201.194.87.2551,022
151201.194.88.0/22201.194.88.1 to 201.194.91.254201.194.91.2551,022
152201.194.92.0/22201.194.92.1 to 201.194.95.254201.194.95.2551,022
153201.194.96.0/22201.194.96.1 to 201.194.99.254201.194.99.2551,022
154201.194.100.0/22201.194.100.1 to 201.194.103.254201.194.103.2551,022
155201.194.104.0/22201.194.104.1 to 201.194.107.254201.194.107.2551,022
156201.194.108.0/22201.194.108.1 to 201.194.111.254201.194.111.2551,022
157201.194.112.0/22201.194.112.1 to 201.194.115.254201.194.115.2551,022
158201.194.116.0/22201.194.116.1 to 201.194.119.254201.194.119.2551,022
159201.194.120.0/22201.194.120.1 to 201.194.123.254201.194.123.2551,022
160201.194.124.0/22201.194.124.1 to 201.194.127.254201.194.127.2551,022
161201.194.128.0/22201.194.128.1 to 201.194.131.254201.194.131.2551,022
162201.194.132.0/22201.194.132.1 to 201.194.135.254201.194.135.2551,022
163201.194.136.0/22201.194.136.1 to 201.194.139.254201.194.139.2551,022
164201.194.140.0/22201.194.140.1 to 201.194.143.254201.194.143.2551,022
165201.194.144.0/22201.194.144.1 to 201.194.147.254201.194.147.2551,022
166201.194.148.0/22201.194.148.1 to 201.194.151.254201.194.151.2551,022
167201.194.152.0/22201.194.152.1 to 201.194.155.254201.194.155.2551,022
168201.194.156.0/22201.194.156.1 to 201.194.159.254201.194.159.2551,022
169201.194.160.0/22201.194.160.1 to 201.194.163.254201.194.163.2551,022
170201.194.164.0/22201.194.164.1 to 201.194.167.254201.194.167.2551,022
171201.194.168.0/22201.194.168.1 to 201.194.171.254201.194.171.2551,022
172201.194.172.0/22201.194.172.1 to 201.194.175.254201.194.175.2551,022
173201.194.176.0/22201.194.176.1 to 201.194.179.254201.194.179.2551,022
174201.194.180.0/22201.194.180.1 to 201.194.183.254201.194.183.2551,022
175201.194.184.0/22201.194.184.1 to 201.194.187.254201.194.187.2551,022
176201.194.188.0/22201.194.188.1 to 201.194.191.254201.194.191.2551,022
177201.194.192.0/22201.194.192.1 to 201.194.195.254201.194.195.2551,022
178201.194.196.0/22201.194.196.1 to 201.194.199.254201.194.199.2551,022
179201.194.200.0/22201.194.200.1 to 201.194.203.254201.194.203.2551,022
180201.194.204.0/22201.194.204.1 to 201.194.207.254201.194.207.2551,022
181201.194.208.0/22201.194.208.1 to 201.194.211.254201.194.211.2551,022
182201.194.212.0/22201.194.212.1 to 201.194.215.254201.194.215.2551,022
183201.194.216.0/22201.194.216.1 to 201.194.219.254201.194.219.2551,022
184201.194.220.0/22201.194.220.1 to 201.194.223.254201.194.223.2551,022
185201.194.224.0/22201.194.224.1 to 201.194.227.254201.194.227.2551,022
186201.194.228.0/22201.194.228.1 to 201.194.231.254201.194.231.2551,022
187201.194.232.0/22201.194.232.1 to 201.194.235.254201.194.235.2551,022
188201.194.236.0/22201.194.236.1 to 201.194.239.254201.194.239.2551,022
189201.194.240.0/22201.194.240.1 to 201.194.243.254201.194.243.2551,022
190201.194.244.0/22201.194.244.1 to 201.194.247.254201.194.247.2551,022
191201.194.248.0/22201.194.248.1 to 201.194.251.254201.194.251.2551,022
192201.194.252.0/22201.194.252.1 to 201.194.255.254201.194.255.2551,022
193201.195.0.0/22201.195.0.1 to 201.195.3.254201.195.3.2551,022
194201.195.4.0/22201.195.4.1 to 201.195.7.254201.195.7.2551,022
195201.195.8.0/22201.195.8.1 to 201.195.11.254201.195.11.2551,022
196201.195.12.0/22201.195.12.1 to 201.195.15.254201.195.15.2551,022
197201.195.16.0/22201.195.16.1 to 201.195.19.254201.195.19.2551,022
198201.195.20.0/22201.195.20.1 to 201.195.23.254201.195.23.2551,022
199201.195.24.0/22201.195.24.1 to 201.195.27.254201.195.27.2551,022
200201.195.28.0/22201.195.28.1 to 201.195.31.254201.195.31.2551,022
201201.195.32.0/22201.195.32.1 to 201.195.35.254201.195.35.2551,022
202201.195.36.0/22201.195.36.1 to 201.195.39.254201.195.39.2551,022
203201.195.40.0/22201.195.40.1 to 201.195.43.254201.195.43.2551,022
204201.195.44.0/22201.195.44.1 to 201.195.47.254201.195.47.2551,022
205201.195.48.0/22201.195.48.1 to 201.195.51.254201.195.51.2551,022
206201.195.52.0/22201.195.52.1 to 201.195.55.254201.195.55.2551,022
207201.195.56.0/22201.195.56.1 to 201.195.59.254201.195.59.2551,022
208201.195.60.0/22201.195.60.1 to 201.195.63.254201.195.63.2551,022
209201.195.64.0/22201.195.64.1 to 201.195.67.254201.195.67.2551,022
210201.195.68.0/22201.195.68.1 to 201.195.71.254201.195.71.2551,022
211201.195.72.0/22201.195.72.1 to 201.195.75.254201.195.75.2551,022
212201.195.76.0/22201.195.76.1 to 201.195.79.254201.195.79.2551,022
213201.195.80.0/22201.195.80.1 to 201.195.83.254201.195.83.2551,022
214201.195.84.0/22201.195.84.1 to 201.195.87.254201.195.87.2551,022
215201.195.88.0/22201.195.88.1 to 201.195.91.254201.195.91.2551,022
216201.195.92.0/22201.195.92.1 to 201.195.95.254201.195.95.2551,022
217201.195.96.0/22201.195.96.1 to 201.195.99.254201.195.99.2551,022
218201.195.100.0/22201.195.100.1 to 201.195.103.254201.195.103.2551,022
219201.195.104.0/22201.195.104.1 to 201.195.107.254201.195.107.2551,022
220201.195.108.0/22201.195.108.1 to 201.195.111.254201.195.111.2551,022
221201.195.112.0/22201.195.112.1 to 201.195.115.254201.195.115.2551,022
222201.195.116.0/22201.195.116.1 to 201.195.119.254201.195.119.2551,022
223201.195.120.0/22201.195.120.1 to 201.195.123.254201.195.123.2551,022
224201.195.124.0/22201.195.124.1 to 201.195.127.254201.195.127.2551,022
225201.195.128.0/22201.195.128.1 to 201.195.131.254201.195.131.2551,022
226201.195.132.0/22201.195.132.1 to 201.195.135.254201.195.135.2551,022
227201.195.136.0/22201.195.136.1 to 201.195.139.254201.195.139.2551,022
228201.195.140.0/22201.195.140.1 to 201.195.143.254201.195.143.2551,022
229201.195.144.0/22201.195.144.1 to 201.195.147.254201.195.147.2551,022
230201.195.148.0/22201.195.148.1 to 201.195.151.254201.195.151.2551,022
231201.195.152.0/22201.195.152.1 to 201.195.155.254201.195.155.2551,022
232201.195.156.0/22201.195.156.1 to 201.195.159.254201.195.159.2551,022
233201.195.160.0/22201.195.160.1 to 201.195.163.254201.195.163.2551,022
234201.195.164.0/22201.195.164.1 to 201.195.167.254201.195.167.2551,022
235201.195.168.0/22201.195.168.1 to 201.195.171.254201.195.171.2551,022
236201.195.172.0/22201.195.172.1 to 201.195.175.254201.195.175.2551,022
237201.195.176.0/22201.195.176.1 to 201.195.179.254201.195.179.2551,022
238201.195.180.0/22201.195.180.1 to 201.195.183.254201.195.183.2551,022
239201.195.184.0/22201.195.184.1 to 201.195.187.254201.195.187.2551,022
240201.195.188.0/22201.195.188.1 to 201.195.191.254201.195.191.2551,022
241201.195.192.0/22201.195.192.1 to 201.195.195.254201.195.195.2551,022
242201.195.196.0/22201.195.196.1 to 201.195.199.254201.195.199.2551,022
243201.195.200.0/22201.195.200.1 to 201.195.203.254201.195.203.2551,022
244201.195.204.0/22201.195.204.1 to 201.195.207.254201.195.207.2551,022
245201.195.208.0/22201.195.208.1 to 201.195.211.254201.195.211.2551,022
246201.195.212.0/22201.195.212.1 to 201.195.215.254201.195.215.2551,022
247201.195.216.0/22201.195.216.1 to 201.195.219.254201.195.219.2551,022
248201.195.220.0/22201.195.220.1 to 201.195.223.254201.195.223.2551,022
249201.195.224.0/22201.195.224.1 to 201.195.227.254201.195.227.2551,022
250201.195.228.0/22201.195.228.1 to 201.195.231.254201.195.231.2551,022
251201.195.232.0/22201.195.232.1 to 201.195.235.254201.195.235.2551,022
252201.195.236.0/22201.195.236.1 to 201.195.239.254201.195.239.2551,022
253201.195.240.0/22201.195.240.1 to 201.195.243.254201.195.243.2551,022
254201.195.244.0/22201.195.244.1 to 201.195.247.254201.195.247.2551,022
255201.195.248.0/22201.195.248.1 to 201.195.251.254201.195.251.2551,022
256201.195.252.0/22201.195.252.1 to 201.195.255.254201.195.255.2551,022

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.