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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.

Network199.72.0.0/13
Usable hosts524,286
Subnet mask255.248.0.0
Addresses524,288
Network address
199.72.0.0
Broadcast address
199.79.255.255
First usable
199.72.0.1
Last usable
199.79.255.254
Usable hosts
524,286 (524,288 less the network and broadcast addresses)
Subnet mask
255.248.0.0
Wildcard mask
0.7.255.255 (Cisco ACLs, OSPF)
Prefix length
/13
Type
Public public
Old class
C (default /24)
As numbers
Hex C7480000 · Integer 3343384576 to 3343908863
Reverse DNS zones
72.199.in-addr.arpa
73.199.in-addr.arpa
74.199.in-addr.arpa
75.199.in-addr.arpa
76.199.in-addr.arpa
77.199.in-addr.arpa
78.199.in-addr.arpa
79.199.in-addr.arpa
/13 is not on a 8-bit boundary, so it takes 8 /16 zones.
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address11000111.01001000.00000000.00000000199.72.0.0
Subnet mask11111111.11111000.00000000.00000000255.248.0.0
Network11000111.01001000.00000000.00000000199.72.0.0
Broadcast11000111.01001111.11111111.11111111199.79.255.255
Split into smaller subnets/22
/14 (2)/15 (4)/16 (8)/17 (16)/18 (32)/19 (64)/20 (128)/21 (256)/22 (512)/23 (1,024)/24 (2,048)/25 (4,096)

199.72.0.0/13 makes 512 subnets of /22; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
1199.72.0.0/22199.72.0.1 to 199.72.3.254199.72.3.2551,022
2199.72.4.0/22199.72.4.1 to 199.72.7.254199.72.7.2551,022
3199.72.8.0/22199.72.8.1 to 199.72.11.254199.72.11.2551,022
4199.72.12.0/22199.72.12.1 to 199.72.15.254199.72.15.2551,022
5199.72.16.0/22199.72.16.1 to 199.72.19.254199.72.19.2551,022
6199.72.20.0/22199.72.20.1 to 199.72.23.254199.72.23.2551,022
7199.72.24.0/22199.72.24.1 to 199.72.27.254199.72.27.2551,022
8199.72.28.0/22199.72.28.1 to 199.72.31.254199.72.31.2551,022
9199.72.32.0/22199.72.32.1 to 199.72.35.254199.72.35.2551,022
10199.72.36.0/22199.72.36.1 to 199.72.39.254199.72.39.2551,022
11199.72.40.0/22199.72.40.1 to 199.72.43.254199.72.43.2551,022
12199.72.44.0/22199.72.44.1 to 199.72.47.254199.72.47.2551,022
13199.72.48.0/22199.72.48.1 to 199.72.51.254199.72.51.2551,022
14199.72.52.0/22199.72.52.1 to 199.72.55.254199.72.55.2551,022
15199.72.56.0/22199.72.56.1 to 199.72.59.254199.72.59.2551,022
16199.72.60.0/22199.72.60.1 to 199.72.63.254199.72.63.2551,022
17199.72.64.0/22199.72.64.1 to 199.72.67.254199.72.67.2551,022
18199.72.68.0/22199.72.68.1 to 199.72.71.254199.72.71.2551,022
19199.72.72.0/22199.72.72.1 to 199.72.75.254199.72.75.2551,022
20199.72.76.0/22199.72.76.1 to 199.72.79.254199.72.79.2551,022
21199.72.80.0/22199.72.80.1 to 199.72.83.254199.72.83.2551,022
22199.72.84.0/22199.72.84.1 to 199.72.87.254199.72.87.2551,022
23199.72.88.0/22199.72.88.1 to 199.72.91.254199.72.91.2551,022
24199.72.92.0/22199.72.92.1 to 199.72.95.254199.72.95.2551,022
25199.72.96.0/22199.72.96.1 to 199.72.99.254199.72.99.2551,022
26199.72.100.0/22199.72.100.1 to 199.72.103.254199.72.103.2551,022
27199.72.104.0/22199.72.104.1 to 199.72.107.254199.72.107.2551,022
28199.72.108.0/22199.72.108.1 to 199.72.111.254199.72.111.2551,022
29199.72.112.0/22199.72.112.1 to 199.72.115.254199.72.115.2551,022
30199.72.116.0/22199.72.116.1 to 199.72.119.254199.72.119.2551,022
31199.72.120.0/22199.72.120.1 to 199.72.123.254199.72.123.2551,022
32199.72.124.0/22199.72.124.1 to 199.72.127.254199.72.127.2551,022
33199.72.128.0/22199.72.128.1 to 199.72.131.254199.72.131.2551,022
34199.72.132.0/22199.72.132.1 to 199.72.135.254199.72.135.2551,022
35199.72.136.0/22199.72.136.1 to 199.72.139.254199.72.139.2551,022
36199.72.140.0/22199.72.140.1 to 199.72.143.254199.72.143.2551,022
37199.72.144.0/22199.72.144.1 to 199.72.147.254199.72.147.2551,022
38199.72.148.0/22199.72.148.1 to 199.72.151.254199.72.151.2551,022
39199.72.152.0/22199.72.152.1 to 199.72.155.254199.72.155.2551,022
40199.72.156.0/22199.72.156.1 to 199.72.159.254199.72.159.2551,022
41199.72.160.0/22199.72.160.1 to 199.72.163.254199.72.163.2551,022
42199.72.164.0/22199.72.164.1 to 199.72.167.254199.72.167.2551,022
43199.72.168.0/22199.72.168.1 to 199.72.171.254199.72.171.2551,022
44199.72.172.0/22199.72.172.1 to 199.72.175.254199.72.175.2551,022
45199.72.176.0/22199.72.176.1 to 199.72.179.254199.72.179.2551,022
46199.72.180.0/22199.72.180.1 to 199.72.183.254199.72.183.2551,022
47199.72.184.0/22199.72.184.1 to 199.72.187.254199.72.187.2551,022
48199.72.188.0/22199.72.188.1 to 199.72.191.254199.72.191.2551,022
49199.72.192.0/22199.72.192.1 to 199.72.195.254199.72.195.2551,022
50199.72.196.0/22199.72.196.1 to 199.72.199.254199.72.199.2551,022
51199.72.200.0/22199.72.200.1 to 199.72.203.254199.72.203.2551,022
52199.72.204.0/22199.72.204.1 to 199.72.207.254199.72.207.2551,022
53199.72.208.0/22199.72.208.1 to 199.72.211.254199.72.211.2551,022
54199.72.212.0/22199.72.212.1 to 199.72.215.254199.72.215.2551,022
55199.72.216.0/22199.72.216.1 to 199.72.219.254199.72.219.2551,022
56199.72.220.0/22199.72.220.1 to 199.72.223.254199.72.223.2551,022
57199.72.224.0/22199.72.224.1 to 199.72.227.254199.72.227.2551,022
58199.72.228.0/22199.72.228.1 to 199.72.231.254199.72.231.2551,022
59199.72.232.0/22199.72.232.1 to 199.72.235.254199.72.235.2551,022
60199.72.236.0/22199.72.236.1 to 199.72.239.254199.72.239.2551,022
61199.72.240.0/22199.72.240.1 to 199.72.243.254199.72.243.2551,022
62199.72.244.0/22199.72.244.1 to 199.72.247.254199.72.247.2551,022
63199.72.248.0/22199.72.248.1 to 199.72.251.254199.72.251.2551,022
64199.72.252.0/22199.72.252.1 to 199.72.255.254199.72.255.2551,022
65199.73.0.0/22199.73.0.1 to 199.73.3.254199.73.3.2551,022
66199.73.4.0/22199.73.4.1 to 199.73.7.254199.73.7.2551,022
67199.73.8.0/22199.73.8.1 to 199.73.11.254199.73.11.2551,022
68199.73.12.0/22199.73.12.1 to 199.73.15.254199.73.15.2551,022
69199.73.16.0/22199.73.16.1 to 199.73.19.254199.73.19.2551,022
70199.73.20.0/22199.73.20.1 to 199.73.23.254199.73.23.2551,022
71199.73.24.0/22199.73.24.1 to 199.73.27.254199.73.27.2551,022
72199.73.28.0/22199.73.28.1 to 199.73.31.254199.73.31.2551,022
73199.73.32.0/22199.73.32.1 to 199.73.35.254199.73.35.2551,022
74199.73.36.0/22199.73.36.1 to 199.73.39.254199.73.39.2551,022
75199.73.40.0/22199.73.40.1 to 199.73.43.254199.73.43.2551,022
76199.73.44.0/22199.73.44.1 to 199.73.47.254199.73.47.2551,022
77199.73.48.0/22199.73.48.1 to 199.73.51.254199.73.51.2551,022
78199.73.52.0/22199.73.52.1 to 199.73.55.254199.73.55.2551,022
79199.73.56.0/22199.73.56.1 to 199.73.59.254199.73.59.2551,022
80199.73.60.0/22199.73.60.1 to 199.73.63.254199.73.63.2551,022
81199.73.64.0/22199.73.64.1 to 199.73.67.254199.73.67.2551,022
82199.73.68.0/22199.73.68.1 to 199.73.71.254199.73.71.2551,022
83199.73.72.0/22199.73.72.1 to 199.73.75.254199.73.75.2551,022
84199.73.76.0/22199.73.76.1 to 199.73.79.254199.73.79.2551,022
85199.73.80.0/22199.73.80.1 to 199.73.83.254199.73.83.2551,022
86199.73.84.0/22199.73.84.1 to 199.73.87.254199.73.87.2551,022
87199.73.88.0/22199.73.88.1 to 199.73.91.254199.73.91.2551,022
88199.73.92.0/22199.73.92.1 to 199.73.95.254199.73.95.2551,022
89199.73.96.0/22199.73.96.1 to 199.73.99.254199.73.99.2551,022
90199.73.100.0/22199.73.100.1 to 199.73.103.254199.73.103.2551,022
91199.73.104.0/22199.73.104.1 to 199.73.107.254199.73.107.2551,022
92199.73.108.0/22199.73.108.1 to 199.73.111.254199.73.111.2551,022
93199.73.112.0/22199.73.112.1 to 199.73.115.254199.73.115.2551,022
94199.73.116.0/22199.73.116.1 to 199.73.119.254199.73.119.2551,022
95199.73.120.0/22199.73.120.1 to 199.73.123.254199.73.123.2551,022
96199.73.124.0/22199.73.124.1 to 199.73.127.254199.73.127.2551,022
97199.73.128.0/22199.73.128.1 to 199.73.131.254199.73.131.2551,022
98199.73.132.0/22199.73.132.1 to 199.73.135.254199.73.135.2551,022
99199.73.136.0/22199.73.136.1 to 199.73.139.254199.73.139.2551,022
100199.73.140.0/22199.73.140.1 to 199.73.143.254199.73.143.2551,022
101199.73.144.0/22199.73.144.1 to 199.73.147.254199.73.147.2551,022
102199.73.148.0/22199.73.148.1 to 199.73.151.254199.73.151.2551,022
103199.73.152.0/22199.73.152.1 to 199.73.155.254199.73.155.2551,022
104199.73.156.0/22199.73.156.1 to 199.73.159.254199.73.159.2551,022
105199.73.160.0/22199.73.160.1 to 199.73.163.254199.73.163.2551,022
106199.73.164.0/22199.73.164.1 to 199.73.167.254199.73.167.2551,022
107199.73.168.0/22199.73.168.1 to 199.73.171.254199.73.171.2551,022
108199.73.172.0/22199.73.172.1 to 199.73.175.254199.73.175.2551,022
109199.73.176.0/22199.73.176.1 to 199.73.179.254199.73.179.2551,022
110199.73.180.0/22199.73.180.1 to 199.73.183.254199.73.183.2551,022
111199.73.184.0/22199.73.184.1 to 199.73.187.254199.73.187.2551,022
112199.73.188.0/22199.73.188.1 to 199.73.191.254199.73.191.2551,022
113199.73.192.0/22199.73.192.1 to 199.73.195.254199.73.195.2551,022
114199.73.196.0/22199.73.196.1 to 199.73.199.254199.73.199.2551,022
115199.73.200.0/22199.73.200.1 to 199.73.203.254199.73.203.2551,022
116199.73.204.0/22199.73.204.1 to 199.73.207.254199.73.207.2551,022
117199.73.208.0/22199.73.208.1 to 199.73.211.254199.73.211.2551,022
118199.73.212.0/22199.73.212.1 to 199.73.215.254199.73.215.2551,022
119199.73.216.0/22199.73.216.1 to 199.73.219.254199.73.219.2551,022
120199.73.220.0/22199.73.220.1 to 199.73.223.254199.73.223.2551,022
121199.73.224.0/22199.73.224.1 to 199.73.227.254199.73.227.2551,022
122199.73.228.0/22199.73.228.1 to 199.73.231.254199.73.231.2551,022
123199.73.232.0/22199.73.232.1 to 199.73.235.254199.73.235.2551,022
124199.73.236.0/22199.73.236.1 to 199.73.239.254199.73.239.2551,022
125199.73.240.0/22199.73.240.1 to 199.73.243.254199.73.243.2551,022
126199.73.244.0/22199.73.244.1 to 199.73.247.254199.73.247.2551,022
127199.73.248.0/22199.73.248.1 to 199.73.251.254199.73.251.2551,022
128199.73.252.0/22199.73.252.1 to 199.73.255.254199.73.255.2551,022
129199.74.0.0/22199.74.0.1 to 199.74.3.254199.74.3.2551,022
130199.74.4.0/22199.74.4.1 to 199.74.7.254199.74.7.2551,022
131199.74.8.0/22199.74.8.1 to 199.74.11.254199.74.11.2551,022
132199.74.12.0/22199.74.12.1 to 199.74.15.254199.74.15.2551,022
133199.74.16.0/22199.74.16.1 to 199.74.19.254199.74.19.2551,022
134199.74.20.0/22199.74.20.1 to 199.74.23.254199.74.23.2551,022
135199.74.24.0/22199.74.24.1 to 199.74.27.254199.74.27.2551,022
136199.74.28.0/22199.74.28.1 to 199.74.31.254199.74.31.2551,022
137199.74.32.0/22199.74.32.1 to 199.74.35.254199.74.35.2551,022
138199.74.36.0/22199.74.36.1 to 199.74.39.254199.74.39.2551,022
139199.74.40.0/22199.74.40.1 to 199.74.43.254199.74.43.2551,022
140199.74.44.0/22199.74.44.1 to 199.74.47.254199.74.47.2551,022
141199.74.48.0/22199.74.48.1 to 199.74.51.254199.74.51.2551,022
142199.74.52.0/22199.74.52.1 to 199.74.55.254199.74.55.2551,022
143199.74.56.0/22199.74.56.1 to 199.74.59.254199.74.59.2551,022
144199.74.60.0/22199.74.60.1 to 199.74.63.254199.74.63.2551,022
145199.74.64.0/22199.74.64.1 to 199.74.67.254199.74.67.2551,022
146199.74.68.0/22199.74.68.1 to 199.74.71.254199.74.71.2551,022
147199.74.72.0/22199.74.72.1 to 199.74.75.254199.74.75.2551,022
148199.74.76.0/22199.74.76.1 to 199.74.79.254199.74.79.2551,022
149199.74.80.0/22199.74.80.1 to 199.74.83.254199.74.83.2551,022
150199.74.84.0/22199.74.84.1 to 199.74.87.254199.74.87.2551,022
151199.74.88.0/22199.74.88.1 to 199.74.91.254199.74.91.2551,022
152199.74.92.0/22199.74.92.1 to 199.74.95.254199.74.95.2551,022
153199.74.96.0/22199.74.96.1 to 199.74.99.254199.74.99.2551,022
154199.74.100.0/22199.74.100.1 to 199.74.103.254199.74.103.2551,022
155199.74.104.0/22199.74.104.1 to 199.74.107.254199.74.107.2551,022
156199.74.108.0/22199.74.108.1 to 199.74.111.254199.74.111.2551,022
157199.74.112.0/22199.74.112.1 to 199.74.115.254199.74.115.2551,022
158199.74.116.0/22199.74.116.1 to 199.74.119.254199.74.119.2551,022
159199.74.120.0/22199.74.120.1 to 199.74.123.254199.74.123.2551,022
160199.74.124.0/22199.74.124.1 to 199.74.127.254199.74.127.2551,022
161199.74.128.0/22199.74.128.1 to 199.74.131.254199.74.131.2551,022
162199.74.132.0/22199.74.132.1 to 199.74.135.254199.74.135.2551,022
163199.74.136.0/22199.74.136.1 to 199.74.139.254199.74.139.2551,022
164199.74.140.0/22199.74.140.1 to 199.74.143.254199.74.143.2551,022
165199.74.144.0/22199.74.144.1 to 199.74.147.254199.74.147.2551,022
166199.74.148.0/22199.74.148.1 to 199.74.151.254199.74.151.2551,022
167199.74.152.0/22199.74.152.1 to 199.74.155.254199.74.155.2551,022
168199.74.156.0/22199.74.156.1 to 199.74.159.254199.74.159.2551,022
169199.74.160.0/22199.74.160.1 to 199.74.163.254199.74.163.2551,022
170199.74.164.0/22199.74.164.1 to 199.74.167.254199.74.167.2551,022
171199.74.168.0/22199.74.168.1 to 199.74.171.254199.74.171.2551,022
172199.74.172.0/22199.74.172.1 to 199.74.175.254199.74.175.2551,022
173199.74.176.0/22199.74.176.1 to 199.74.179.254199.74.179.2551,022
174199.74.180.0/22199.74.180.1 to 199.74.183.254199.74.183.2551,022
175199.74.184.0/22199.74.184.1 to 199.74.187.254199.74.187.2551,022
176199.74.188.0/22199.74.188.1 to 199.74.191.254199.74.191.2551,022
177199.74.192.0/22199.74.192.1 to 199.74.195.254199.74.195.2551,022
178199.74.196.0/22199.74.196.1 to 199.74.199.254199.74.199.2551,022
179199.74.200.0/22199.74.200.1 to 199.74.203.254199.74.203.2551,022
180199.74.204.0/22199.74.204.1 to 199.74.207.254199.74.207.2551,022
181199.74.208.0/22199.74.208.1 to 199.74.211.254199.74.211.2551,022
182199.74.212.0/22199.74.212.1 to 199.74.215.254199.74.215.2551,022
183199.74.216.0/22199.74.216.1 to 199.74.219.254199.74.219.2551,022
184199.74.220.0/22199.74.220.1 to 199.74.223.254199.74.223.2551,022
185199.74.224.0/22199.74.224.1 to 199.74.227.254199.74.227.2551,022
186199.74.228.0/22199.74.228.1 to 199.74.231.254199.74.231.2551,022
187199.74.232.0/22199.74.232.1 to 199.74.235.254199.74.235.2551,022
188199.74.236.0/22199.74.236.1 to 199.74.239.254199.74.239.2551,022
189199.74.240.0/22199.74.240.1 to 199.74.243.254199.74.243.2551,022
190199.74.244.0/22199.74.244.1 to 199.74.247.254199.74.247.2551,022
191199.74.248.0/22199.74.248.1 to 199.74.251.254199.74.251.2551,022
192199.74.252.0/22199.74.252.1 to 199.74.255.254199.74.255.2551,022
193199.75.0.0/22199.75.0.1 to 199.75.3.254199.75.3.2551,022
194199.75.4.0/22199.75.4.1 to 199.75.7.254199.75.7.2551,022
195199.75.8.0/22199.75.8.1 to 199.75.11.254199.75.11.2551,022
196199.75.12.0/22199.75.12.1 to 199.75.15.254199.75.15.2551,022
197199.75.16.0/22199.75.16.1 to 199.75.19.254199.75.19.2551,022
198199.75.20.0/22199.75.20.1 to 199.75.23.254199.75.23.2551,022
199199.75.24.0/22199.75.24.1 to 199.75.27.254199.75.27.2551,022
200199.75.28.0/22199.75.28.1 to 199.75.31.254199.75.31.2551,022
201199.75.32.0/22199.75.32.1 to 199.75.35.254199.75.35.2551,022
202199.75.36.0/22199.75.36.1 to 199.75.39.254199.75.39.2551,022
203199.75.40.0/22199.75.40.1 to 199.75.43.254199.75.43.2551,022
204199.75.44.0/22199.75.44.1 to 199.75.47.254199.75.47.2551,022
205199.75.48.0/22199.75.48.1 to 199.75.51.254199.75.51.2551,022
206199.75.52.0/22199.75.52.1 to 199.75.55.254199.75.55.2551,022
207199.75.56.0/22199.75.56.1 to 199.75.59.254199.75.59.2551,022
208199.75.60.0/22199.75.60.1 to 199.75.63.254199.75.63.2551,022
209199.75.64.0/22199.75.64.1 to 199.75.67.254199.75.67.2551,022
210199.75.68.0/22199.75.68.1 to 199.75.71.254199.75.71.2551,022
211199.75.72.0/22199.75.72.1 to 199.75.75.254199.75.75.2551,022
212199.75.76.0/22199.75.76.1 to 199.75.79.254199.75.79.2551,022
213199.75.80.0/22199.75.80.1 to 199.75.83.254199.75.83.2551,022
214199.75.84.0/22199.75.84.1 to 199.75.87.254199.75.87.2551,022
215199.75.88.0/22199.75.88.1 to 199.75.91.254199.75.91.2551,022
216199.75.92.0/22199.75.92.1 to 199.75.95.254199.75.95.2551,022
217199.75.96.0/22199.75.96.1 to 199.75.99.254199.75.99.2551,022
218199.75.100.0/22199.75.100.1 to 199.75.103.254199.75.103.2551,022
219199.75.104.0/22199.75.104.1 to 199.75.107.254199.75.107.2551,022
220199.75.108.0/22199.75.108.1 to 199.75.111.254199.75.111.2551,022
221199.75.112.0/22199.75.112.1 to 199.75.115.254199.75.115.2551,022
222199.75.116.0/22199.75.116.1 to 199.75.119.254199.75.119.2551,022
223199.75.120.0/22199.75.120.1 to 199.75.123.254199.75.123.2551,022
224199.75.124.0/22199.75.124.1 to 199.75.127.254199.75.127.2551,022
225199.75.128.0/22199.75.128.1 to 199.75.131.254199.75.131.2551,022
226199.75.132.0/22199.75.132.1 to 199.75.135.254199.75.135.2551,022
227199.75.136.0/22199.75.136.1 to 199.75.139.254199.75.139.2551,022
228199.75.140.0/22199.75.140.1 to 199.75.143.254199.75.143.2551,022
229199.75.144.0/22199.75.144.1 to 199.75.147.254199.75.147.2551,022
230199.75.148.0/22199.75.148.1 to 199.75.151.254199.75.151.2551,022
231199.75.152.0/22199.75.152.1 to 199.75.155.254199.75.155.2551,022
232199.75.156.0/22199.75.156.1 to 199.75.159.254199.75.159.2551,022
233199.75.160.0/22199.75.160.1 to 199.75.163.254199.75.163.2551,022
234199.75.164.0/22199.75.164.1 to 199.75.167.254199.75.167.2551,022
235199.75.168.0/22199.75.168.1 to 199.75.171.254199.75.171.2551,022
236199.75.172.0/22199.75.172.1 to 199.75.175.254199.75.175.2551,022
237199.75.176.0/22199.75.176.1 to 199.75.179.254199.75.179.2551,022
238199.75.180.0/22199.75.180.1 to 199.75.183.254199.75.183.2551,022
239199.75.184.0/22199.75.184.1 to 199.75.187.254199.75.187.2551,022
240199.75.188.0/22199.75.188.1 to 199.75.191.254199.75.191.2551,022
241199.75.192.0/22199.75.192.1 to 199.75.195.254199.75.195.2551,022
242199.75.196.0/22199.75.196.1 to 199.75.199.254199.75.199.2551,022
243199.75.200.0/22199.75.200.1 to 199.75.203.254199.75.203.2551,022
244199.75.204.0/22199.75.204.1 to 199.75.207.254199.75.207.2551,022
245199.75.208.0/22199.75.208.1 to 199.75.211.254199.75.211.2551,022
246199.75.212.0/22199.75.212.1 to 199.75.215.254199.75.215.2551,022
247199.75.216.0/22199.75.216.1 to 199.75.219.254199.75.219.2551,022
248199.75.220.0/22199.75.220.1 to 199.75.223.254199.75.223.2551,022
249199.75.224.0/22199.75.224.1 to 199.75.227.254199.75.227.2551,022
250199.75.228.0/22199.75.228.1 to 199.75.231.254199.75.231.2551,022
251199.75.232.0/22199.75.232.1 to 199.75.235.254199.75.235.2551,022
252199.75.236.0/22199.75.236.1 to 199.75.239.254199.75.239.2551,022
253199.75.240.0/22199.75.240.1 to 199.75.243.254199.75.243.2551,022
254199.75.244.0/22199.75.244.1 to 199.75.247.254199.75.247.2551,022
255199.75.248.0/22199.75.248.1 to 199.75.251.254199.75.251.2551,022
256199.75.252.0/22199.75.252.1 to 199.75.255.254199.75.255.2551,022

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.