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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.

Network220.0.0.0/6
Usable hosts67,108,862
Subnet mask252.0.0.0
Addresses67,108,864
Network address
220.0.0.0
Broadcast address
223.255.255.255
First usable
220.0.0.1
Last usable
223.255.255.254
Usable hosts
67,108,862 (67,108,864 less the network and broadcast addresses)
Subnet mask
252.0.0.0
Wildcard mask
3.255.255.255 (Cisco ACLs, OSPF)
Prefix length
/6
Type
Public public
Old class
C (default /24)
As numbers
Hex DC000000 · Integer 3690987520 to 3758096383
Reverse DNS zones
220.in-addr.arpa
221.in-addr.arpa
222.in-addr.arpa
223.in-addr.arpa
/6 is not on a 8-bit boundary, so it takes 4 /8 zones.
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address11011100.00000000.00000000.00000000220.0.0.0
Subnet mask11111100.00000000.00000000.00000000252.0.0.0
Network11011100.00000000.00000000.00000000220.0.0.0
Broadcast11011111.11111111.11111111.11111111223.255.255.255
Split into smaller subnets/14
/7 (2)/8 (4)/9 (8)/10 (16)/11 (32)/12 (64)/13 (128)/14 (256)/15 (512)/16 (1,024)/17 (2,048)/18 (4,096)

220.0.0.0/6 makes 256 subnets of /14.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
1220.0.0.0/14220.0.0.1 to 220.3.255.254220.3.255.255262,142
2220.4.0.0/14220.4.0.1 to 220.7.255.254220.7.255.255262,142
3220.8.0.0/14220.8.0.1 to 220.11.255.254220.11.255.255262,142
4220.12.0.0/14220.12.0.1 to 220.15.255.254220.15.255.255262,142
5220.16.0.0/14220.16.0.1 to 220.19.255.254220.19.255.255262,142
6220.20.0.0/14220.20.0.1 to 220.23.255.254220.23.255.255262,142
7220.24.0.0/14220.24.0.1 to 220.27.255.254220.27.255.255262,142
8220.28.0.0/14220.28.0.1 to 220.31.255.254220.31.255.255262,142
9220.32.0.0/14220.32.0.1 to 220.35.255.254220.35.255.255262,142
10220.36.0.0/14220.36.0.1 to 220.39.255.254220.39.255.255262,142
11220.40.0.0/14220.40.0.1 to 220.43.255.254220.43.255.255262,142
12220.44.0.0/14220.44.0.1 to 220.47.255.254220.47.255.255262,142
13220.48.0.0/14220.48.0.1 to 220.51.255.254220.51.255.255262,142
14220.52.0.0/14220.52.0.1 to 220.55.255.254220.55.255.255262,142
15220.56.0.0/14220.56.0.1 to 220.59.255.254220.59.255.255262,142
16220.60.0.0/14220.60.0.1 to 220.63.255.254220.63.255.255262,142
17220.64.0.0/14220.64.0.1 to 220.67.255.254220.67.255.255262,142
18220.68.0.0/14220.68.0.1 to 220.71.255.254220.71.255.255262,142
19220.72.0.0/14220.72.0.1 to 220.75.255.254220.75.255.255262,142
20220.76.0.0/14220.76.0.1 to 220.79.255.254220.79.255.255262,142
21220.80.0.0/14220.80.0.1 to 220.83.255.254220.83.255.255262,142
22220.84.0.0/14220.84.0.1 to 220.87.255.254220.87.255.255262,142
23220.88.0.0/14220.88.0.1 to 220.91.255.254220.91.255.255262,142
24220.92.0.0/14220.92.0.1 to 220.95.255.254220.95.255.255262,142
25220.96.0.0/14220.96.0.1 to 220.99.255.254220.99.255.255262,142
26220.100.0.0/14220.100.0.1 to 220.103.255.254220.103.255.255262,142
27220.104.0.0/14220.104.0.1 to 220.107.255.254220.107.255.255262,142
28220.108.0.0/14220.108.0.1 to 220.111.255.254220.111.255.255262,142
29220.112.0.0/14220.112.0.1 to 220.115.255.254220.115.255.255262,142
30220.116.0.0/14220.116.0.1 to 220.119.255.254220.119.255.255262,142
31220.120.0.0/14220.120.0.1 to 220.123.255.254220.123.255.255262,142
32220.124.0.0/14220.124.0.1 to 220.127.255.254220.127.255.255262,142
33220.128.0.0/14220.128.0.1 to 220.131.255.254220.131.255.255262,142
34220.132.0.0/14220.132.0.1 to 220.135.255.254220.135.255.255262,142
35220.136.0.0/14220.136.0.1 to 220.139.255.254220.139.255.255262,142
36220.140.0.0/14220.140.0.1 to 220.143.255.254220.143.255.255262,142
37220.144.0.0/14220.144.0.1 to 220.147.255.254220.147.255.255262,142
38220.148.0.0/14220.148.0.1 to 220.151.255.254220.151.255.255262,142
39220.152.0.0/14220.152.0.1 to 220.155.255.254220.155.255.255262,142
40220.156.0.0/14220.156.0.1 to 220.159.255.254220.159.255.255262,142
41220.160.0.0/14220.160.0.1 to 220.163.255.254220.163.255.255262,142
42220.164.0.0/14220.164.0.1 to 220.167.255.254220.167.255.255262,142
43220.168.0.0/14220.168.0.1 to 220.171.255.254220.171.255.255262,142
44220.172.0.0/14220.172.0.1 to 220.175.255.254220.175.255.255262,142
45220.176.0.0/14220.176.0.1 to 220.179.255.254220.179.255.255262,142
46220.180.0.0/14220.180.0.1 to 220.183.255.254220.183.255.255262,142
47220.184.0.0/14220.184.0.1 to 220.187.255.254220.187.255.255262,142
48220.188.0.0/14220.188.0.1 to 220.191.255.254220.191.255.255262,142
49220.192.0.0/14220.192.0.1 to 220.195.255.254220.195.255.255262,142
50220.196.0.0/14220.196.0.1 to 220.199.255.254220.199.255.255262,142
51220.200.0.0/14220.200.0.1 to 220.203.255.254220.203.255.255262,142
52220.204.0.0/14220.204.0.1 to 220.207.255.254220.207.255.255262,142
53220.208.0.0/14220.208.0.1 to 220.211.255.254220.211.255.255262,142
54220.212.0.0/14220.212.0.1 to 220.215.255.254220.215.255.255262,142
55220.216.0.0/14220.216.0.1 to 220.219.255.254220.219.255.255262,142
56220.220.0.0/14220.220.0.1 to 220.223.255.254220.223.255.255262,142
57220.224.0.0/14220.224.0.1 to 220.227.255.254220.227.255.255262,142
58220.228.0.0/14220.228.0.1 to 220.231.255.254220.231.255.255262,142
59220.232.0.0/14220.232.0.1 to 220.235.255.254220.235.255.255262,142
60220.236.0.0/14220.236.0.1 to 220.239.255.254220.239.255.255262,142
61220.240.0.0/14220.240.0.1 to 220.243.255.254220.243.255.255262,142
62220.244.0.0/14220.244.0.1 to 220.247.255.254220.247.255.255262,142
63220.248.0.0/14220.248.0.1 to 220.251.255.254220.251.255.255262,142
64220.252.0.0/14220.252.0.1 to 220.255.255.254220.255.255.255262,142
65221.0.0.0/14221.0.0.1 to 221.3.255.254221.3.255.255262,142
66221.4.0.0/14221.4.0.1 to 221.7.255.254221.7.255.255262,142
67221.8.0.0/14221.8.0.1 to 221.11.255.254221.11.255.255262,142
68221.12.0.0/14221.12.0.1 to 221.15.255.254221.15.255.255262,142
69221.16.0.0/14221.16.0.1 to 221.19.255.254221.19.255.255262,142
70221.20.0.0/14221.20.0.1 to 221.23.255.254221.23.255.255262,142
71221.24.0.0/14221.24.0.1 to 221.27.255.254221.27.255.255262,142
72221.28.0.0/14221.28.0.1 to 221.31.255.254221.31.255.255262,142
73221.32.0.0/14221.32.0.1 to 221.35.255.254221.35.255.255262,142
74221.36.0.0/14221.36.0.1 to 221.39.255.254221.39.255.255262,142
75221.40.0.0/14221.40.0.1 to 221.43.255.254221.43.255.255262,142
76221.44.0.0/14221.44.0.1 to 221.47.255.254221.47.255.255262,142
77221.48.0.0/14221.48.0.1 to 221.51.255.254221.51.255.255262,142
78221.52.0.0/14221.52.0.1 to 221.55.255.254221.55.255.255262,142
79221.56.0.0/14221.56.0.1 to 221.59.255.254221.59.255.255262,142
80221.60.0.0/14221.60.0.1 to 221.63.255.254221.63.255.255262,142
81221.64.0.0/14221.64.0.1 to 221.67.255.254221.67.255.255262,142
82221.68.0.0/14221.68.0.1 to 221.71.255.254221.71.255.255262,142
83221.72.0.0/14221.72.0.1 to 221.75.255.254221.75.255.255262,142
84221.76.0.0/14221.76.0.1 to 221.79.255.254221.79.255.255262,142
85221.80.0.0/14221.80.0.1 to 221.83.255.254221.83.255.255262,142
86221.84.0.0/14221.84.0.1 to 221.87.255.254221.87.255.255262,142
87221.88.0.0/14221.88.0.1 to 221.91.255.254221.91.255.255262,142
88221.92.0.0/14221.92.0.1 to 221.95.255.254221.95.255.255262,142
89221.96.0.0/14221.96.0.1 to 221.99.255.254221.99.255.255262,142
90221.100.0.0/14221.100.0.1 to 221.103.255.254221.103.255.255262,142
91221.104.0.0/14221.104.0.1 to 221.107.255.254221.107.255.255262,142
92221.108.0.0/14221.108.0.1 to 221.111.255.254221.111.255.255262,142
93221.112.0.0/14221.112.0.1 to 221.115.255.254221.115.255.255262,142
94221.116.0.0/14221.116.0.1 to 221.119.255.254221.119.255.255262,142
95221.120.0.0/14221.120.0.1 to 221.123.255.254221.123.255.255262,142
96221.124.0.0/14221.124.0.1 to 221.127.255.254221.127.255.255262,142
97221.128.0.0/14221.128.0.1 to 221.131.255.254221.131.255.255262,142
98221.132.0.0/14221.132.0.1 to 221.135.255.254221.135.255.255262,142
99221.136.0.0/14221.136.0.1 to 221.139.255.254221.139.255.255262,142
100221.140.0.0/14221.140.0.1 to 221.143.255.254221.143.255.255262,142
101221.144.0.0/14221.144.0.1 to 221.147.255.254221.147.255.255262,142
102221.148.0.0/14221.148.0.1 to 221.151.255.254221.151.255.255262,142
103221.152.0.0/14221.152.0.1 to 221.155.255.254221.155.255.255262,142
104221.156.0.0/14221.156.0.1 to 221.159.255.254221.159.255.255262,142
105221.160.0.0/14221.160.0.1 to 221.163.255.254221.163.255.255262,142
106221.164.0.0/14221.164.0.1 to 221.167.255.254221.167.255.255262,142
107221.168.0.0/14221.168.0.1 to 221.171.255.254221.171.255.255262,142
108221.172.0.0/14221.172.0.1 to 221.175.255.254221.175.255.255262,142
109221.176.0.0/14221.176.0.1 to 221.179.255.254221.179.255.255262,142
110221.180.0.0/14221.180.0.1 to 221.183.255.254221.183.255.255262,142
111221.184.0.0/14221.184.0.1 to 221.187.255.254221.187.255.255262,142
112221.188.0.0/14221.188.0.1 to 221.191.255.254221.191.255.255262,142
113221.192.0.0/14221.192.0.1 to 221.195.255.254221.195.255.255262,142
114221.196.0.0/14221.196.0.1 to 221.199.255.254221.199.255.255262,142
115221.200.0.0/14221.200.0.1 to 221.203.255.254221.203.255.255262,142
116221.204.0.0/14221.204.0.1 to 221.207.255.254221.207.255.255262,142
117221.208.0.0/14221.208.0.1 to 221.211.255.254221.211.255.255262,142
118221.212.0.0/14221.212.0.1 to 221.215.255.254221.215.255.255262,142
119221.216.0.0/14221.216.0.1 to 221.219.255.254221.219.255.255262,142
120221.220.0.0/14221.220.0.1 to 221.223.255.254221.223.255.255262,142
121221.224.0.0/14221.224.0.1 to 221.227.255.254221.227.255.255262,142
122221.228.0.0/14221.228.0.1 to 221.231.255.254221.231.255.255262,142
123221.232.0.0/14221.232.0.1 to 221.235.255.254221.235.255.255262,142
124221.236.0.0/14221.236.0.1 to 221.239.255.254221.239.255.255262,142
125221.240.0.0/14221.240.0.1 to 221.243.255.254221.243.255.255262,142
126221.244.0.0/14221.244.0.1 to 221.247.255.254221.247.255.255262,142
127221.248.0.0/14221.248.0.1 to 221.251.255.254221.251.255.255262,142
128221.252.0.0/14221.252.0.1 to 221.255.255.254221.255.255.255262,142
129222.0.0.0/14222.0.0.1 to 222.3.255.254222.3.255.255262,142
130222.4.0.0/14222.4.0.1 to 222.7.255.254222.7.255.255262,142
131222.8.0.0/14222.8.0.1 to 222.11.255.254222.11.255.255262,142
132222.12.0.0/14222.12.0.1 to 222.15.255.254222.15.255.255262,142
133222.16.0.0/14222.16.0.1 to 222.19.255.254222.19.255.255262,142
134222.20.0.0/14222.20.0.1 to 222.23.255.254222.23.255.255262,142
135222.24.0.0/14222.24.0.1 to 222.27.255.254222.27.255.255262,142
136222.28.0.0/14222.28.0.1 to 222.31.255.254222.31.255.255262,142
137222.32.0.0/14222.32.0.1 to 222.35.255.254222.35.255.255262,142
138222.36.0.0/14222.36.0.1 to 222.39.255.254222.39.255.255262,142
139222.40.0.0/14222.40.0.1 to 222.43.255.254222.43.255.255262,142
140222.44.0.0/14222.44.0.1 to 222.47.255.254222.47.255.255262,142
141222.48.0.0/14222.48.0.1 to 222.51.255.254222.51.255.255262,142
142222.52.0.0/14222.52.0.1 to 222.55.255.254222.55.255.255262,142
143222.56.0.0/14222.56.0.1 to 222.59.255.254222.59.255.255262,142
144222.60.0.0/14222.60.0.1 to 222.63.255.254222.63.255.255262,142
145222.64.0.0/14222.64.0.1 to 222.67.255.254222.67.255.255262,142
146222.68.0.0/14222.68.0.1 to 222.71.255.254222.71.255.255262,142
147222.72.0.0/14222.72.0.1 to 222.75.255.254222.75.255.255262,142
148222.76.0.0/14222.76.0.1 to 222.79.255.254222.79.255.255262,142
149222.80.0.0/14222.80.0.1 to 222.83.255.254222.83.255.255262,142
150222.84.0.0/14222.84.0.1 to 222.87.255.254222.87.255.255262,142
151222.88.0.0/14222.88.0.1 to 222.91.255.254222.91.255.255262,142
152222.92.0.0/14222.92.0.1 to 222.95.255.254222.95.255.255262,142
153222.96.0.0/14222.96.0.1 to 222.99.255.254222.99.255.255262,142
154222.100.0.0/14222.100.0.1 to 222.103.255.254222.103.255.255262,142
155222.104.0.0/14222.104.0.1 to 222.107.255.254222.107.255.255262,142
156222.108.0.0/14222.108.0.1 to 222.111.255.254222.111.255.255262,142
157222.112.0.0/14222.112.0.1 to 222.115.255.254222.115.255.255262,142
158222.116.0.0/14222.116.0.1 to 222.119.255.254222.119.255.255262,142
159222.120.0.0/14222.120.0.1 to 222.123.255.254222.123.255.255262,142
160222.124.0.0/14222.124.0.1 to 222.127.255.254222.127.255.255262,142
161222.128.0.0/14222.128.0.1 to 222.131.255.254222.131.255.255262,142
162222.132.0.0/14222.132.0.1 to 222.135.255.254222.135.255.255262,142
163222.136.0.0/14222.136.0.1 to 222.139.255.254222.139.255.255262,142
164222.140.0.0/14222.140.0.1 to 222.143.255.254222.143.255.255262,142
165222.144.0.0/14222.144.0.1 to 222.147.255.254222.147.255.255262,142
166222.148.0.0/14222.148.0.1 to 222.151.255.254222.151.255.255262,142
167222.152.0.0/14222.152.0.1 to 222.155.255.254222.155.255.255262,142
168222.156.0.0/14222.156.0.1 to 222.159.255.254222.159.255.255262,142
169222.160.0.0/14222.160.0.1 to 222.163.255.254222.163.255.255262,142
170222.164.0.0/14222.164.0.1 to 222.167.255.254222.167.255.255262,142
171222.168.0.0/14222.168.0.1 to 222.171.255.254222.171.255.255262,142
172222.172.0.0/14222.172.0.1 to 222.175.255.254222.175.255.255262,142
173222.176.0.0/14222.176.0.1 to 222.179.255.254222.179.255.255262,142
174222.180.0.0/14222.180.0.1 to 222.183.255.254222.183.255.255262,142
175222.184.0.0/14222.184.0.1 to 222.187.255.254222.187.255.255262,142
176222.188.0.0/14222.188.0.1 to 222.191.255.254222.191.255.255262,142
177222.192.0.0/14222.192.0.1 to 222.195.255.254222.195.255.255262,142
178222.196.0.0/14222.196.0.1 to 222.199.255.254222.199.255.255262,142
179222.200.0.0/14222.200.0.1 to 222.203.255.254222.203.255.255262,142
180222.204.0.0/14222.204.0.1 to 222.207.255.254222.207.255.255262,142
181222.208.0.0/14222.208.0.1 to 222.211.255.254222.211.255.255262,142
182222.212.0.0/14222.212.0.1 to 222.215.255.254222.215.255.255262,142
183222.216.0.0/14222.216.0.1 to 222.219.255.254222.219.255.255262,142
184222.220.0.0/14222.220.0.1 to 222.223.255.254222.223.255.255262,142
185222.224.0.0/14222.224.0.1 to 222.227.255.254222.227.255.255262,142
186222.228.0.0/14222.228.0.1 to 222.231.255.254222.231.255.255262,142
187222.232.0.0/14222.232.0.1 to 222.235.255.254222.235.255.255262,142
188222.236.0.0/14222.236.0.1 to 222.239.255.254222.239.255.255262,142
189222.240.0.0/14222.240.0.1 to 222.243.255.254222.243.255.255262,142
190222.244.0.0/14222.244.0.1 to 222.247.255.254222.247.255.255262,142
191222.248.0.0/14222.248.0.1 to 222.251.255.254222.251.255.255262,142
192222.252.0.0/14222.252.0.1 to 222.255.255.254222.255.255.255262,142
193223.0.0.0/14223.0.0.1 to 223.3.255.254223.3.255.255262,142
194223.4.0.0/14223.4.0.1 to 223.7.255.254223.7.255.255262,142
195223.8.0.0/14223.8.0.1 to 223.11.255.254223.11.255.255262,142
196223.12.0.0/14223.12.0.1 to 223.15.255.254223.15.255.255262,142
197223.16.0.0/14223.16.0.1 to 223.19.255.254223.19.255.255262,142
198223.20.0.0/14223.20.0.1 to 223.23.255.254223.23.255.255262,142
199223.24.0.0/14223.24.0.1 to 223.27.255.254223.27.255.255262,142
200223.28.0.0/14223.28.0.1 to 223.31.255.254223.31.255.255262,142
201223.32.0.0/14223.32.0.1 to 223.35.255.254223.35.255.255262,142
202223.36.0.0/14223.36.0.1 to 223.39.255.254223.39.255.255262,142
203223.40.0.0/14223.40.0.1 to 223.43.255.254223.43.255.255262,142
204223.44.0.0/14223.44.0.1 to 223.47.255.254223.47.255.255262,142
205223.48.0.0/14223.48.0.1 to 223.51.255.254223.51.255.255262,142
206223.52.0.0/14223.52.0.1 to 223.55.255.254223.55.255.255262,142
207223.56.0.0/14223.56.0.1 to 223.59.255.254223.59.255.255262,142
208223.60.0.0/14223.60.0.1 to 223.63.255.254223.63.255.255262,142
209223.64.0.0/14223.64.0.1 to 223.67.255.254223.67.255.255262,142
210223.68.0.0/14223.68.0.1 to 223.71.255.254223.71.255.255262,142
211223.72.0.0/14223.72.0.1 to 223.75.255.254223.75.255.255262,142
212223.76.0.0/14223.76.0.1 to 223.79.255.254223.79.255.255262,142
213223.80.0.0/14223.80.0.1 to 223.83.255.254223.83.255.255262,142
214223.84.0.0/14223.84.0.1 to 223.87.255.254223.87.255.255262,142
215223.88.0.0/14223.88.0.1 to 223.91.255.254223.91.255.255262,142
216223.92.0.0/14223.92.0.1 to 223.95.255.254223.95.255.255262,142
217223.96.0.0/14223.96.0.1 to 223.99.255.254223.99.255.255262,142
218223.100.0.0/14223.100.0.1 to 223.103.255.254223.103.255.255262,142
219223.104.0.0/14223.104.0.1 to 223.107.255.254223.107.255.255262,142
220223.108.0.0/14223.108.0.1 to 223.111.255.254223.111.255.255262,142
221223.112.0.0/14223.112.0.1 to 223.115.255.254223.115.255.255262,142
222223.116.0.0/14223.116.0.1 to 223.119.255.254223.119.255.255262,142
223223.120.0.0/14223.120.0.1 to 223.123.255.254223.123.255.255262,142
224223.124.0.0/14223.124.0.1 to 223.127.255.254223.127.255.255262,142
225223.128.0.0/14223.128.0.1 to 223.131.255.254223.131.255.255262,142
226223.132.0.0/14223.132.0.1 to 223.135.255.254223.135.255.255262,142
227223.136.0.0/14223.136.0.1 to 223.139.255.254223.139.255.255262,142
228223.140.0.0/14223.140.0.1 to 223.143.255.254223.143.255.255262,142
229223.144.0.0/14223.144.0.1 to 223.147.255.254223.147.255.255262,142
230223.148.0.0/14223.148.0.1 to 223.151.255.254223.151.255.255262,142
231223.152.0.0/14223.152.0.1 to 223.155.255.254223.155.255.255262,142
232223.156.0.0/14223.156.0.1 to 223.159.255.254223.159.255.255262,142
233223.160.0.0/14223.160.0.1 to 223.163.255.254223.163.255.255262,142
234223.164.0.0/14223.164.0.1 to 223.167.255.254223.167.255.255262,142
235223.168.0.0/14223.168.0.1 to 223.171.255.254223.171.255.255262,142
236223.172.0.0/14223.172.0.1 to 223.175.255.254223.175.255.255262,142
237223.176.0.0/14223.176.0.1 to 223.179.255.254223.179.255.255262,142
238223.180.0.0/14223.180.0.1 to 223.183.255.254223.183.255.255262,142
239223.184.0.0/14223.184.0.1 to 223.187.255.254223.187.255.255262,142
240223.188.0.0/14223.188.0.1 to 223.191.255.254223.191.255.255262,142
241223.192.0.0/14223.192.0.1 to 223.195.255.254223.195.255.255262,142
242223.196.0.0/14223.196.0.1 to 223.199.255.254223.199.255.255262,142
243223.200.0.0/14223.200.0.1 to 223.203.255.254223.203.255.255262,142
244223.204.0.0/14223.204.0.1 to 223.207.255.254223.207.255.255262,142
245223.208.0.0/14223.208.0.1 to 223.211.255.254223.211.255.255262,142
246223.212.0.0/14223.212.0.1 to 223.215.255.254223.215.255.255262,142
247223.216.0.0/14223.216.0.1 to 223.219.255.254223.219.255.255262,142
248223.220.0.0/14223.220.0.1 to 223.223.255.254223.223.255.255262,142
249223.224.0.0/14223.224.0.1 to 223.227.255.254223.227.255.255262,142
250223.228.0.0/14223.228.0.1 to 223.231.255.254223.231.255.255262,142
251223.232.0.0/14223.232.0.1 to 223.235.255.254223.235.255.255262,142
252223.236.0.0/14223.236.0.1 to 223.239.255.254223.239.255.255262,142
253223.240.0.0/14223.240.0.1 to 223.243.255.254223.243.255.255262,142
254223.244.0.0/14223.244.0.1 to 223.247.255.254223.247.255.255262,142
255223.248.0.0/14223.248.0.1 to 223.251.255.254223.251.255.255262,142
256223.252.0.0/14223.252.0.1 to 223.255.255.254223.255.255.255262,142

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.