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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.

Network200.0.0.0/10
Usable hosts4,194,302
Subnet mask255.192.0.0
Addresses4,194,304
Network address
200.0.0.0
Broadcast address
200.63.255.255
First usable
200.0.0.1
Last usable
200.63.255.254
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 C8000000 · Integer 3355443200 to 3359637503
Reverse DNS zones
0.200.in-addr.arpa
1.200.in-addr.arpa
2.200.in-addr.arpa
3.200.in-addr.arpa
4.200.in-addr.arpa
5.200.in-addr.arpa
6.200.in-addr.arpa
7.200.in-addr.arpa
8.200.in-addr.arpa
9.200.in-addr.arpa
10.200.in-addr.arpa
11.200.in-addr.arpa
12.200.in-addr.arpa
13.200.in-addr.arpa
14.200.in-addr.arpa
15.200.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
Address11001000.00000000.00000000.00000000200.0.0.0
Subnet mask11111111.11000000.00000000.00000000255.192.0.0
Network11001000.00000000.00000000.00000000200.0.0.0
Broadcast11001000.00111111.11111111.11111111200.63.255.255
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)

200.0.0.0/10 makes 4,096 subnets of /22; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
1200.0.0.0/22200.0.0.1 to 200.0.3.254200.0.3.2551,022
2200.0.4.0/22200.0.4.1 to 200.0.7.254200.0.7.2551,022
3200.0.8.0/22200.0.8.1 to 200.0.11.254200.0.11.2551,022
4200.0.12.0/22200.0.12.1 to 200.0.15.254200.0.15.2551,022
5200.0.16.0/22200.0.16.1 to 200.0.19.254200.0.19.2551,022
6200.0.20.0/22200.0.20.1 to 200.0.23.254200.0.23.2551,022
7200.0.24.0/22200.0.24.1 to 200.0.27.254200.0.27.2551,022
8200.0.28.0/22200.0.28.1 to 200.0.31.254200.0.31.2551,022
9200.0.32.0/22200.0.32.1 to 200.0.35.254200.0.35.2551,022
10200.0.36.0/22200.0.36.1 to 200.0.39.254200.0.39.2551,022
11200.0.40.0/22200.0.40.1 to 200.0.43.254200.0.43.2551,022
12200.0.44.0/22200.0.44.1 to 200.0.47.254200.0.47.2551,022
13200.0.48.0/22200.0.48.1 to 200.0.51.254200.0.51.2551,022
14200.0.52.0/22200.0.52.1 to 200.0.55.254200.0.55.2551,022
15200.0.56.0/22200.0.56.1 to 200.0.59.254200.0.59.2551,022
16200.0.60.0/22200.0.60.1 to 200.0.63.254200.0.63.2551,022
17200.0.64.0/22200.0.64.1 to 200.0.67.254200.0.67.2551,022
18200.0.68.0/22200.0.68.1 to 200.0.71.254200.0.71.2551,022
19200.0.72.0/22200.0.72.1 to 200.0.75.254200.0.75.2551,022
20200.0.76.0/22200.0.76.1 to 200.0.79.254200.0.79.2551,022
21200.0.80.0/22200.0.80.1 to 200.0.83.254200.0.83.2551,022
22200.0.84.0/22200.0.84.1 to 200.0.87.254200.0.87.2551,022
23200.0.88.0/22200.0.88.1 to 200.0.91.254200.0.91.2551,022
24200.0.92.0/22200.0.92.1 to 200.0.95.254200.0.95.2551,022
25200.0.96.0/22200.0.96.1 to 200.0.99.254200.0.99.2551,022
26200.0.100.0/22200.0.100.1 to 200.0.103.254200.0.103.2551,022
27200.0.104.0/22200.0.104.1 to 200.0.107.254200.0.107.2551,022
28200.0.108.0/22200.0.108.1 to 200.0.111.254200.0.111.2551,022
29200.0.112.0/22200.0.112.1 to 200.0.115.254200.0.115.2551,022
30200.0.116.0/22200.0.116.1 to 200.0.119.254200.0.119.2551,022
31200.0.120.0/22200.0.120.1 to 200.0.123.254200.0.123.2551,022
32200.0.124.0/22200.0.124.1 to 200.0.127.254200.0.127.2551,022
33200.0.128.0/22200.0.128.1 to 200.0.131.254200.0.131.2551,022
34200.0.132.0/22200.0.132.1 to 200.0.135.254200.0.135.2551,022
35200.0.136.0/22200.0.136.1 to 200.0.139.254200.0.139.2551,022
36200.0.140.0/22200.0.140.1 to 200.0.143.254200.0.143.2551,022
37200.0.144.0/22200.0.144.1 to 200.0.147.254200.0.147.2551,022
38200.0.148.0/22200.0.148.1 to 200.0.151.254200.0.151.2551,022
39200.0.152.0/22200.0.152.1 to 200.0.155.254200.0.155.2551,022
40200.0.156.0/22200.0.156.1 to 200.0.159.254200.0.159.2551,022
41200.0.160.0/22200.0.160.1 to 200.0.163.254200.0.163.2551,022
42200.0.164.0/22200.0.164.1 to 200.0.167.254200.0.167.2551,022
43200.0.168.0/22200.0.168.1 to 200.0.171.254200.0.171.2551,022
44200.0.172.0/22200.0.172.1 to 200.0.175.254200.0.175.2551,022
45200.0.176.0/22200.0.176.1 to 200.0.179.254200.0.179.2551,022
46200.0.180.0/22200.0.180.1 to 200.0.183.254200.0.183.2551,022
47200.0.184.0/22200.0.184.1 to 200.0.187.254200.0.187.2551,022
48200.0.188.0/22200.0.188.1 to 200.0.191.254200.0.191.2551,022
49200.0.192.0/22200.0.192.1 to 200.0.195.254200.0.195.2551,022
50200.0.196.0/22200.0.196.1 to 200.0.199.254200.0.199.2551,022
51200.0.200.0/22200.0.200.1 to 200.0.203.254200.0.203.2551,022
52200.0.204.0/22200.0.204.1 to 200.0.207.254200.0.207.2551,022
53200.0.208.0/22200.0.208.1 to 200.0.211.254200.0.211.2551,022
54200.0.212.0/22200.0.212.1 to 200.0.215.254200.0.215.2551,022
55200.0.216.0/22200.0.216.1 to 200.0.219.254200.0.219.2551,022
56200.0.220.0/22200.0.220.1 to 200.0.223.254200.0.223.2551,022
57200.0.224.0/22200.0.224.1 to 200.0.227.254200.0.227.2551,022
58200.0.228.0/22200.0.228.1 to 200.0.231.254200.0.231.2551,022
59200.0.232.0/22200.0.232.1 to 200.0.235.254200.0.235.2551,022
60200.0.236.0/22200.0.236.1 to 200.0.239.254200.0.239.2551,022
61200.0.240.0/22200.0.240.1 to 200.0.243.254200.0.243.2551,022
62200.0.244.0/22200.0.244.1 to 200.0.247.254200.0.247.2551,022
63200.0.248.0/22200.0.248.1 to 200.0.251.254200.0.251.2551,022
64200.0.252.0/22200.0.252.1 to 200.0.255.254200.0.255.2551,022
65200.1.0.0/22200.1.0.1 to 200.1.3.254200.1.3.2551,022
66200.1.4.0/22200.1.4.1 to 200.1.7.254200.1.7.2551,022
67200.1.8.0/22200.1.8.1 to 200.1.11.254200.1.11.2551,022
68200.1.12.0/22200.1.12.1 to 200.1.15.254200.1.15.2551,022
69200.1.16.0/22200.1.16.1 to 200.1.19.254200.1.19.2551,022
70200.1.20.0/22200.1.20.1 to 200.1.23.254200.1.23.2551,022
71200.1.24.0/22200.1.24.1 to 200.1.27.254200.1.27.2551,022
72200.1.28.0/22200.1.28.1 to 200.1.31.254200.1.31.2551,022
73200.1.32.0/22200.1.32.1 to 200.1.35.254200.1.35.2551,022
74200.1.36.0/22200.1.36.1 to 200.1.39.254200.1.39.2551,022
75200.1.40.0/22200.1.40.1 to 200.1.43.254200.1.43.2551,022
76200.1.44.0/22200.1.44.1 to 200.1.47.254200.1.47.2551,022
77200.1.48.0/22200.1.48.1 to 200.1.51.254200.1.51.2551,022
78200.1.52.0/22200.1.52.1 to 200.1.55.254200.1.55.2551,022
79200.1.56.0/22200.1.56.1 to 200.1.59.254200.1.59.2551,022
80200.1.60.0/22200.1.60.1 to 200.1.63.254200.1.63.2551,022
81200.1.64.0/22200.1.64.1 to 200.1.67.254200.1.67.2551,022
82200.1.68.0/22200.1.68.1 to 200.1.71.254200.1.71.2551,022
83200.1.72.0/22200.1.72.1 to 200.1.75.254200.1.75.2551,022
84200.1.76.0/22200.1.76.1 to 200.1.79.254200.1.79.2551,022
85200.1.80.0/22200.1.80.1 to 200.1.83.254200.1.83.2551,022
86200.1.84.0/22200.1.84.1 to 200.1.87.254200.1.87.2551,022
87200.1.88.0/22200.1.88.1 to 200.1.91.254200.1.91.2551,022
88200.1.92.0/22200.1.92.1 to 200.1.95.254200.1.95.2551,022
89200.1.96.0/22200.1.96.1 to 200.1.99.254200.1.99.2551,022
90200.1.100.0/22200.1.100.1 to 200.1.103.254200.1.103.2551,022
91200.1.104.0/22200.1.104.1 to 200.1.107.254200.1.107.2551,022
92200.1.108.0/22200.1.108.1 to 200.1.111.254200.1.111.2551,022
93200.1.112.0/22200.1.112.1 to 200.1.115.254200.1.115.2551,022
94200.1.116.0/22200.1.116.1 to 200.1.119.254200.1.119.2551,022
95200.1.120.0/22200.1.120.1 to 200.1.123.254200.1.123.2551,022
96200.1.124.0/22200.1.124.1 to 200.1.127.254200.1.127.2551,022
97200.1.128.0/22200.1.128.1 to 200.1.131.254200.1.131.2551,022
98200.1.132.0/22200.1.132.1 to 200.1.135.254200.1.135.2551,022
99200.1.136.0/22200.1.136.1 to 200.1.139.254200.1.139.2551,022
100200.1.140.0/22200.1.140.1 to 200.1.143.254200.1.143.2551,022
101200.1.144.0/22200.1.144.1 to 200.1.147.254200.1.147.2551,022
102200.1.148.0/22200.1.148.1 to 200.1.151.254200.1.151.2551,022
103200.1.152.0/22200.1.152.1 to 200.1.155.254200.1.155.2551,022
104200.1.156.0/22200.1.156.1 to 200.1.159.254200.1.159.2551,022
105200.1.160.0/22200.1.160.1 to 200.1.163.254200.1.163.2551,022
106200.1.164.0/22200.1.164.1 to 200.1.167.254200.1.167.2551,022
107200.1.168.0/22200.1.168.1 to 200.1.171.254200.1.171.2551,022
108200.1.172.0/22200.1.172.1 to 200.1.175.254200.1.175.2551,022
109200.1.176.0/22200.1.176.1 to 200.1.179.254200.1.179.2551,022
110200.1.180.0/22200.1.180.1 to 200.1.183.254200.1.183.2551,022
111200.1.184.0/22200.1.184.1 to 200.1.187.254200.1.187.2551,022
112200.1.188.0/22200.1.188.1 to 200.1.191.254200.1.191.2551,022
113200.1.192.0/22200.1.192.1 to 200.1.195.254200.1.195.2551,022
114200.1.196.0/22200.1.196.1 to 200.1.199.254200.1.199.2551,022
115200.1.200.0/22200.1.200.1 to 200.1.203.254200.1.203.2551,022
116200.1.204.0/22200.1.204.1 to 200.1.207.254200.1.207.2551,022
117200.1.208.0/22200.1.208.1 to 200.1.211.254200.1.211.2551,022
118200.1.212.0/22200.1.212.1 to 200.1.215.254200.1.215.2551,022
119200.1.216.0/22200.1.216.1 to 200.1.219.254200.1.219.2551,022
120200.1.220.0/22200.1.220.1 to 200.1.223.254200.1.223.2551,022
121200.1.224.0/22200.1.224.1 to 200.1.227.254200.1.227.2551,022
122200.1.228.0/22200.1.228.1 to 200.1.231.254200.1.231.2551,022
123200.1.232.0/22200.1.232.1 to 200.1.235.254200.1.235.2551,022
124200.1.236.0/22200.1.236.1 to 200.1.239.254200.1.239.2551,022
125200.1.240.0/22200.1.240.1 to 200.1.243.254200.1.243.2551,022
126200.1.244.0/22200.1.244.1 to 200.1.247.254200.1.247.2551,022
127200.1.248.0/22200.1.248.1 to 200.1.251.254200.1.251.2551,022
128200.1.252.0/22200.1.252.1 to 200.1.255.254200.1.255.2551,022
129200.2.0.0/22200.2.0.1 to 200.2.3.254200.2.3.2551,022
130200.2.4.0/22200.2.4.1 to 200.2.7.254200.2.7.2551,022
131200.2.8.0/22200.2.8.1 to 200.2.11.254200.2.11.2551,022
132200.2.12.0/22200.2.12.1 to 200.2.15.254200.2.15.2551,022
133200.2.16.0/22200.2.16.1 to 200.2.19.254200.2.19.2551,022
134200.2.20.0/22200.2.20.1 to 200.2.23.254200.2.23.2551,022
135200.2.24.0/22200.2.24.1 to 200.2.27.254200.2.27.2551,022
136200.2.28.0/22200.2.28.1 to 200.2.31.254200.2.31.2551,022
137200.2.32.0/22200.2.32.1 to 200.2.35.254200.2.35.2551,022
138200.2.36.0/22200.2.36.1 to 200.2.39.254200.2.39.2551,022
139200.2.40.0/22200.2.40.1 to 200.2.43.254200.2.43.2551,022
140200.2.44.0/22200.2.44.1 to 200.2.47.254200.2.47.2551,022
141200.2.48.0/22200.2.48.1 to 200.2.51.254200.2.51.2551,022
142200.2.52.0/22200.2.52.1 to 200.2.55.254200.2.55.2551,022
143200.2.56.0/22200.2.56.1 to 200.2.59.254200.2.59.2551,022
144200.2.60.0/22200.2.60.1 to 200.2.63.254200.2.63.2551,022
145200.2.64.0/22200.2.64.1 to 200.2.67.254200.2.67.2551,022
146200.2.68.0/22200.2.68.1 to 200.2.71.254200.2.71.2551,022
147200.2.72.0/22200.2.72.1 to 200.2.75.254200.2.75.2551,022
148200.2.76.0/22200.2.76.1 to 200.2.79.254200.2.79.2551,022
149200.2.80.0/22200.2.80.1 to 200.2.83.254200.2.83.2551,022
150200.2.84.0/22200.2.84.1 to 200.2.87.254200.2.87.2551,022
151200.2.88.0/22200.2.88.1 to 200.2.91.254200.2.91.2551,022
152200.2.92.0/22200.2.92.1 to 200.2.95.254200.2.95.2551,022
153200.2.96.0/22200.2.96.1 to 200.2.99.254200.2.99.2551,022
154200.2.100.0/22200.2.100.1 to 200.2.103.254200.2.103.2551,022
155200.2.104.0/22200.2.104.1 to 200.2.107.254200.2.107.2551,022
156200.2.108.0/22200.2.108.1 to 200.2.111.254200.2.111.2551,022
157200.2.112.0/22200.2.112.1 to 200.2.115.254200.2.115.2551,022
158200.2.116.0/22200.2.116.1 to 200.2.119.254200.2.119.2551,022
159200.2.120.0/22200.2.120.1 to 200.2.123.254200.2.123.2551,022
160200.2.124.0/22200.2.124.1 to 200.2.127.254200.2.127.2551,022
161200.2.128.0/22200.2.128.1 to 200.2.131.254200.2.131.2551,022
162200.2.132.0/22200.2.132.1 to 200.2.135.254200.2.135.2551,022
163200.2.136.0/22200.2.136.1 to 200.2.139.254200.2.139.2551,022
164200.2.140.0/22200.2.140.1 to 200.2.143.254200.2.143.2551,022
165200.2.144.0/22200.2.144.1 to 200.2.147.254200.2.147.2551,022
166200.2.148.0/22200.2.148.1 to 200.2.151.254200.2.151.2551,022
167200.2.152.0/22200.2.152.1 to 200.2.155.254200.2.155.2551,022
168200.2.156.0/22200.2.156.1 to 200.2.159.254200.2.159.2551,022
169200.2.160.0/22200.2.160.1 to 200.2.163.254200.2.163.2551,022
170200.2.164.0/22200.2.164.1 to 200.2.167.254200.2.167.2551,022
171200.2.168.0/22200.2.168.1 to 200.2.171.254200.2.171.2551,022
172200.2.172.0/22200.2.172.1 to 200.2.175.254200.2.175.2551,022
173200.2.176.0/22200.2.176.1 to 200.2.179.254200.2.179.2551,022
174200.2.180.0/22200.2.180.1 to 200.2.183.254200.2.183.2551,022
175200.2.184.0/22200.2.184.1 to 200.2.187.254200.2.187.2551,022
176200.2.188.0/22200.2.188.1 to 200.2.191.254200.2.191.2551,022
177200.2.192.0/22200.2.192.1 to 200.2.195.254200.2.195.2551,022
178200.2.196.0/22200.2.196.1 to 200.2.199.254200.2.199.2551,022
179200.2.200.0/22200.2.200.1 to 200.2.203.254200.2.203.2551,022
180200.2.204.0/22200.2.204.1 to 200.2.207.254200.2.207.2551,022
181200.2.208.0/22200.2.208.1 to 200.2.211.254200.2.211.2551,022
182200.2.212.0/22200.2.212.1 to 200.2.215.254200.2.215.2551,022
183200.2.216.0/22200.2.216.1 to 200.2.219.254200.2.219.2551,022
184200.2.220.0/22200.2.220.1 to 200.2.223.254200.2.223.2551,022
185200.2.224.0/22200.2.224.1 to 200.2.227.254200.2.227.2551,022
186200.2.228.0/22200.2.228.1 to 200.2.231.254200.2.231.2551,022
187200.2.232.0/22200.2.232.1 to 200.2.235.254200.2.235.2551,022
188200.2.236.0/22200.2.236.1 to 200.2.239.254200.2.239.2551,022
189200.2.240.0/22200.2.240.1 to 200.2.243.254200.2.243.2551,022
190200.2.244.0/22200.2.244.1 to 200.2.247.254200.2.247.2551,022
191200.2.248.0/22200.2.248.1 to 200.2.251.254200.2.251.2551,022
192200.2.252.0/22200.2.252.1 to 200.2.255.254200.2.255.2551,022
193200.3.0.0/22200.3.0.1 to 200.3.3.254200.3.3.2551,022
194200.3.4.0/22200.3.4.1 to 200.3.7.254200.3.7.2551,022
195200.3.8.0/22200.3.8.1 to 200.3.11.254200.3.11.2551,022
196200.3.12.0/22200.3.12.1 to 200.3.15.254200.3.15.2551,022
197200.3.16.0/22200.3.16.1 to 200.3.19.254200.3.19.2551,022
198200.3.20.0/22200.3.20.1 to 200.3.23.254200.3.23.2551,022
199200.3.24.0/22200.3.24.1 to 200.3.27.254200.3.27.2551,022
200200.3.28.0/22200.3.28.1 to 200.3.31.254200.3.31.2551,022
201200.3.32.0/22200.3.32.1 to 200.3.35.254200.3.35.2551,022
202200.3.36.0/22200.3.36.1 to 200.3.39.254200.3.39.2551,022
203200.3.40.0/22200.3.40.1 to 200.3.43.254200.3.43.2551,022
204200.3.44.0/22200.3.44.1 to 200.3.47.254200.3.47.2551,022
205200.3.48.0/22200.3.48.1 to 200.3.51.254200.3.51.2551,022
206200.3.52.0/22200.3.52.1 to 200.3.55.254200.3.55.2551,022
207200.3.56.0/22200.3.56.1 to 200.3.59.254200.3.59.2551,022
208200.3.60.0/22200.3.60.1 to 200.3.63.254200.3.63.2551,022
209200.3.64.0/22200.3.64.1 to 200.3.67.254200.3.67.2551,022
210200.3.68.0/22200.3.68.1 to 200.3.71.254200.3.71.2551,022
211200.3.72.0/22200.3.72.1 to 200.3.75.254200.3.75.2551,022
212200.3.76.0/22200.3.76.1 to 200.3.79.254200.3.79.2551,022
213200.3.80.0/22200.3.80.1 to 200.3.83.254200.3.83.2551,022
214200.3.84.0/22200.3.84.1 to 200.3.87.254200.3.87.2551,022
215200.3.88.0/22200.3.88.1 to 200.3.91.254200.3.91.2551,022
216200.3.92.0/22200.3.92.1 to 200.3.95.254200.3.95.2551,022
217200.3.96.0/22200.3.96.1 to 200.3.99.254200.3.99.2551,022
218200.3.100.0/22200.3.100.1 to 200.3.103.254200.3.103.2551,022
219200.3.104.0/22200.3.104.1 to 200.3.107.254200.3.107.2551,022
220200.3.108.0/22200.3.108.1 to 200.3.111.254200.3.111.2551,022
221200.3.112.0/22200.3.112.1 to 200.3.115.254200.3.115.2551,022
222200.3.116.0/22200.3.116.1 to 200.3.119.254200.3.119.2551,022
223200.3.120.0/22200.3.120.1 to 200.3.123.254200.3.123.2551,022
224200.3.124.0/22200.3.124.1 to 200.3.127.254200.3.127.2551,022
225200.3.128.0/22200.3.128.1 to 200.3.131.254200.3.131.2551,022
226200.3.132.0/22200.3.132.1 to 200.3.135.254200.3.135.2551,022
227200.3.136.0/22200.3.136.1 to 200.3.139.254200.3.139.2551,022
228200.3.140.0/22200.3.140.1 to 200.3.143.254200.3.143.2551,022
229200.3.144.0/22200.3.144.1 to 200.3.147.254200.3.147.2551,022
230200.3.148.0/22200.3.148.1 to 200.3.151.254200.3.151.2551,022
231200.3.152.0/22200.3.152.1 to 200.3.155.254200.3.155.2551,022
232200.3.156.0/22200.3.156.1 to 200.3.159.254200.3.159.2551,022
233200.3.160.0/22200.3.160.1 to 200.3.163.254200.3.163.2551,022
234200.3.164.0/22200.3.164.1 to 200.3.167.254200.3.167.2551,022
235200.3.168.0/22200.3.168.1 to 200.3.171.254200.3.171.2551,022
236200.3.172.0/22200.3.172.1 to 200.3.175.254200.3.175.2551,022
237200.3.176.0/22200.3.176.1 to 200.3.179.254200.3.179.2551,022
238200.3.180.0/22200.3.180.1 to 200.3.183.254200.3.183.2551,022
239200.3.184.0/22200.3.184.1 to 200.3.187.254200.3.187.2551,022
240200.3.188.0/22200.3.188.1 to 200.3.191.254200.3.191.2551,022
241200.3.192.0/22200.3.192.1 to 200.3.195.254200.3.195.2551,022
242200.3.196.0/22200.3.196.1 to 200.3.199.254200.3.199.2551,022
243200.3.200.0/22200.3.200.1 to 200.3.203.254200.3.203.2551,022
244200.3.204.0/22200.3.204.1 to 200.3.207.254200.3.207.2551,022
245200.3.208.0/22200.3.208.1 to 200.3.211.254200.3.211.2551,022
246200.3.212.0/22200.3.212.1 to 200.3.215.254200.3.215.2551,022
247200.3.216.0/22200.3.216.1 to 200.3.219.254200.3.219.2551,022
248200.3.220.0/22200.3.220.1 to 200.3.223.254200.3.223.2551,022
249200.3.224.0/22200.3.224.1 to 200.3.227.254200.3.227.2551,022
250200.3.228.0/22200.3.228.1 to 200.3.231.254200.3.231.2551,022
251200.3.232.0/22200.3.232.1 to 200.3.235.254200.3.235.2551,022
252200.3.236.0/22200.3.236.1 to 200.3.239.254200.3.239.2551,022
253200.3.240.0/22200.3.240.1 to 200.3.243.254200.3.243.2551,022
254200.3.244.0/22200.3.244.1 to 200.3.247.254200.3.247.2551,022
255200.3.248.0/22200.3.248.1 to 200.3.251.254200.3.251.2551,022
256200.3.252.0/22200.3.252.1 to 200.3.255.254200.3.255.2551,022

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.