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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.

Network244.0.0.0/10
Usable hosts4,194,302
Subnet mask255.192.0.0
Addresses4,194,304
Network address
244.0.0.0
Broadcast address
244.63.255.255
First usable
244.0.0.1
Last usable
244.63.255.254
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
Reserved 240.0.0.0/4
Future use; not usable on most systems
Old class
E (reserved)
As numbers
Hex F4000000 · Integer 4093640704 to 4097835007
Reverse DNS zones
0.244.in-addr.arpa
1.244.in-addr.arpa
2.244.in-addr.arpa
3.244.in-addr.arpa
4.244.in-addr.arpa
5.244.in-addr.arpa
6.244.in-addr.arpa
7.244.in-addr.arpa
8.244.in-addr.arpa
9.244.in-addr.arpa
10.244.in-addr.arpa
11.244.in-addr.arpa
12.244.in-addr.arpa
13.244.in-addr.arpa
14.244.in-addr.arpa
15.244.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
Address11110100.00000000.00000000.00000000244.0.0.0
Subnet mask11111111.11000000.00000000.00000000255.192.0.0
Network11110100.00000000.00000000.00000000244.0.0.0
Broadcast11110100.00111111.11111111.11111111244.63.255.255
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)

244.0.0.0/10 makes 4,096 subnets of /22; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
1244.0.0.0/22244.0.0.1 to 244.0.3.254244.0.3.2551,022
2244.0.4.0/22244.0.4.1 to 244.0.7.254244.0.7.2551,022
3244.0.8.0/22244.0.8.1 to 244.0.11.254244.0.11.2551,022
4244.0.12.0/22244.0.12.1 to 244.0.15.254244.0.15.2551,022
5244.0.16.0/22244.0.16.1 to 244.0.19.254244.0.19.2551,022
6244.0.20.0/22244.0.20.1 to 244.0.23.254244.0.23.2551,022
7244.0.24.0/22244.0.24.1 to 244.0.27.254244.0.27.2551,022
8244.0.28.0/22244.0.28.1 to 244.0.31.254244.0.31.2551,022
9244.0.32.0/22244.0.32.1 to 244.0.35.254244.0.35.2551,022
10244.0.36.0/22244.0.36.1 to 244.0.39.254244.0.39.2551,022
11244.0.40.0/22244.0.40.1 to 244.0.43.254244.0.43.2551,022
12244.0.44.0/22244.0.44.1 to 244.0.47.254244.0.47.2551,022
13244.0.48.0/22244.0.48.1 to 244.0.51.254244.0.51.2551,022
14244.0.52.0/22244.0.52.1 to 244.0.55.254244.0.55.2551,022
15244.0.56.0/22244.0.56.1 to 244.0.59.254244.0.59.2551,022
16244.0.60.0/22244.0.60.1 to 244.0.63.254244.0.63.2551,022
17244.0.64.0/22244.0.64.1 to 244.0.67.254244.0.67.2551,022
18244.0.68.0/22244.0.68.1 to 244.0.71.254244.0.71.2551,022
19244.0.72.0/22244.0.72.1 to 244.0.75.254244.0.75.2551,022
20244.0.76.0/22244.0.76.1 to 244.0.79.254244.0.79.2551,022
21244.0.80.0/22244.0.80.1 to 244.0.83.254244.0.83.2551,022
22244.0.84.0/22244.0.84.1 to 244.0.87.254244.0.87.2551,022
23244.0.88.0/22244.0.88.1 to 244.0.91.254244.0.91.2551,022
24244.0.92.0/22244.0.92.1 to 244.0.95.254244.0.95.2551,022
25244.0.96.0/22244.0.96.1 to 244.0.99.254244.0.99.2551,022
26244.0.100.0/22244.0.100.1 to 244.0.103.254244.0.103.2551,022
27244.0.104.0/22244.0.104.1 to 244.0.107.254244.0.107.2551,022
28244.0.108.0/22244.0.108.1 to 244.0.111.254244.0.111.2551,022
29244.0.112.0/22244.0.112.1 to 244.0.115.254244.0.115.2551,022
30244.0.116.0/22244.0.116.1 to 244.0.119.254244.0.119.2551,022
31244.0.120.0/22244.0.120.1 to 244.0.123.254244.0.123.2551,022
32244.0.124.0/22244.0.124.1 to 244.0.127.254244.0.127.2551,022
33244.0.128.0/22244.0.128.1 to 244.0.131.254244.0.131.2551,022
34244.0.132.0/22244.0.132.1 to 244.0.135.254244.0.135.2551,022
35244.0.136.0/22244.0.136.1 to 244.0.139.254244.0.139.2551,022
36244.0.140.0/22244.0.140.1 to 244.0.143.254244.0.143.2551,022
37244.0.144.0/22244.0.144.1 to 244.0.147.254244.0.147.2551,022
38244.0.148.0/22244.0.148.1 to 244.0.151.254244.0.151.2551,022
39244.0.152.0/22244.0.152.1 to 244.0.155.254244.0.155.2551,022
40244.0.156.0/22244.0.156.1 to 244.0.159.254244.0.159.2551,022
41244.0.160.0/22244.0.160.1 to 244.0.163.254244.0.163.2551,022
42244.0.164.0/22244.0.164.1 to 244.0.167.254244.0.167.2551,022
43244.0.168.0/22244.0.168.1 to 244.0.171.254244.0.171.2551,022
44244.0.172.0/22244.0.172.1 to 244.0.175.254244.0.175.2551,022
45244.0.176.0/22244.0.176.1 to 244.0.179.254244.0.179.2551,022
46244.0.180.0/22244.0.180.1 to 244.0.183.254244.0.183.2551,022
47244.0.184.0/22244.0.184.1 to 244.0.187.254244.0.187.2551,022
48244.0.188.0/22244.0.188.1 to 244.0.191.254244.0.191.2551,022
49244.0.192.0/22244.0.192.1 to 244.0.195.254244.0.195.2551,022
50244.0.196.0/22244.0.196.1 to 244.0.199.254244.0.199.2551,022
51244.0.200.0/22244.0.200.1 to 244.0.203.254244.0.203.2551,022
52244.0.204.0/22244.0.204.1 to 244.0.207.254244.0.207.2551,022
53244.0.208.0/22244.0.208.1 to 244.0.211.254244.0.211.2551,022
54244.0.212.0/22244.0.212.1 to 244.0.215.254244.0.215.2551,022
55244.0.216.0/22244.0.216.1 to 244.0.219.254244.0.219.2551,022
56244.0.220.0/22244.0.220.1 to 244.0.223.254244.0.223.2551,022
57244.0.224.0/22244.0.224.1 to 244.0.227.254244.0.227.2551,022
58244.0.228.0/22244.0.228.1 to 244.0.231.254244.0.231.2551,022
59244.0.232.0/22244.0.232.1 to 244.0.235.254244.0.235.2551,022
60244.0.236.0/22244.0.236.1 to 244.0.239.254244.0.239.2551,022
61244.0.240.0/22244.0.240.1 to 244.0.243.254244.0.243.2551,022
62244.0.244.0/22244.0.244.1 to 244.0.247.254244.0.247.2551,022
63244.0.248.0/22244.0.248.1 to 244.0.251.254244.0.251.2551,022
64244.0.252.0/22244.0.252.1 to 244.0.255.254244.0.255.2551,022
65244.1.0.0/22244.1.0.1 to 244.1.3.254244.1.3.2551,022
66244.1.4.0/22244.1.4.1 to 244.1.7.254244.1.7.2551,022
67244.1.8.0/22244.1.8.1 to 244.1.11.254244.1.11.2551,022
68244.1.12.0/22244.1.12.1 to 244.1.15.254244.1.15.2551,022
69244.1.16.0/22244.1.16.1 to 244.1.19.254244.1.19.2551,022
70244.1.20.0/22244.1.20.1 to 244.1.23.254244.1.23.2551,022
71244.1.24.0/22244.1.24.1 to 244.1.27.254244.1.27.2551,022
72244.1.28.0/22244.1.28.1 to 244.1.31.254244.1.31.2551,022
73244.1.32.0/22244.1.32.1 to 244.1.35.254244.1.35.2551,022
74244.1.36.0/22244.1.36.1 to 244.1.39.254244.1.39.2551,022
75244.1.40.0/22244.1.40.1 to 244.1.43.254244.1.43.2551,022
76244.1.44.0/22244.1.44.1 to 244.1.47.254244.1.47.2551,022
77244.1.48.0/22244.1.48.1 to 244.1.51.254244.1.51.2551,022
78244.1.52.0/22244.1.52.1 to 244.1.55.254244.1.55.2551,022
79244.1.56.0/22244.1.56.1 to 244.1.59.254244.1.59.2551,022
80244.1.60.0/22244.1.60.1 to 244.1.63.254244.1.63.2551,022
81244.1.64.0/22244.1.64.1 to 244.1.67.254244.1.67.2551,022
82244.1.68.0/22244.1.68.1 to 244.1.71.254244.1.71.2551,022
83244.1.72.0/22244.1.72.1 to 244.1.75.254244.1.75.2551,022
84244.1.76.0/22244.1.76.1 to 244.1.79.254244.1.79.2551,022
85244.1.80.0/22244.1.80.1 to 244.1.83.254244.1.83.2551,022
86244.1.84.0/22244.1.84.1 to 244.1.87.254244.1.87.2551,022
87244.1.88.0/22244.1.88.1 to 244.1.91.254244.1.91.2551,022
88244.1.92.0/22244.1.92.1 to 244.1.95.254244.1.95.2551,022
89244.1.96.0/22244.1.96.1 to 244.1.99.254244.1.99.2551,022
90244.1.100.0/22244.1.100.1 to 244.1.103.254244.1.103.2551,022
91244.1.104.0/22244.1.104.1 to 244.1.107.254244.1.107.2551,022
92244.1.108.0/22244.1.108.1 to 244.1.111.254244.1.111.2551,022
93244.1.112.0/22244.1.112.1 to 244.1.115.254244.1.115.2551,022
94244.1.116.0/22244.1.116.1 to 244.1.119.254244.1.119.2551,022
95244.1.120.0/22244.1.120.1 to 244.1.123.254244.1.123.2551,022
96244.1.124.0/22244.1.124.1 to 244.1.127.254244.1.127.2551,022
97244.1.128.0/22244.1.128.1 to 244.1.131.254244.1.131.2551,022
98244.1.132.0/22244.1.132.1 to 244.1.135.254244.1.135.2551,022
99244.1.136.0/22244.1.136.1 to 244.1.139.254244.1.139.2551,022
100244.1.140.0/22244.1.140.1 to 244.1.143.254244.1.143.2551,022
101244.1.144.0/22244.1.144.1 to 244.1.147.254244.1.147.2551,022
102244.1.148.0/22244.1.148.1 to 244.1.151.254244.1.151.2551,022
103244.1.152.0/22244.1.152.1 to 244.1.155.254244.1.155.2551,022
104244.1.156.0/22244.1.156.1 to 244.1.159.254244.1.159.2551,022
105244.1.160.0/22244.1.160.1 to 244.1.163.254244.1.163.2551,022
106244.1.164.0/22244.1.164.1 to 244.1.167.254244.1.167.2551,022
107244.1.168.0/22244.1.168.1 to 244.1.171.254244.1.171.2551,022
108244.1.172.0/22244.1.172.1 to 244.1.175.254244.1.175.2551,022
109244.1.176.0/22244.1.176.1 to 244.1.179.254244.1.179.2551,022
110244.1.180.0/22244.1.180.1 to 244.1.183.254244.1.183.2551,022
111244.1.184.0/22244.1.184.1 to 244.1.187.254244.1.187.2551,022
112244.1.188.0/22244.1.188.1 to 244.1.191.254244.1.191.2551,022
113244.1.192.0/22244.1.192.1 to 244.1.195.254244.1.195.2551,022
114244.1.196.0/22244.1.196.1 to 244.1.199.254244.1.199.2551,022
115244.1.200.0/22244.1.200.1 to 244.1.203.254244.1.203.2551,022
116244.1.204.0/22244.1.204.1 to 244.1.207.254244.1.207.2551,022
117244.1.208.0/22244.1.208.1 to 244.1.211.254244.1.211.2551,022
118244.1.212.0/22244.1.212.1 to 244.1.215.254244.1.215.2551,022
119244.1.216.0/22244.1.216.1 to 244.1.219.254244.1.219.2551,022
120244.1.220.0/22244.1.220.1 to 244.1.223.254244.1.223.2551,022
121244.1.224.0/22244.1.224.1 to 244.1.227.254244.1.227.2551,022
122244.1.228.0/22244.1.228.1 to 244.1.231.254244.1.231.2551,022
123244.1.232.0/22244.1.232.1 to 244.1.235.254244.1.235.2551,022
124244.1.236.0/22244.1.236.1 to 244.1.239.254244.1.239.2551,022
125244.1.240.0/22244.1.240.1 to 244.1.243.254244.1.243.2551,022
126244.1.244.0/22244.1.244.1 to 244.1.247.254244.1.247.2551,022
127244.1.248.0/22244.1.248.1 to 244.1.251.254244.1.251.2551,022
128244.1.252.0/22244.1.252.1 to 244.1.255.254244.1.255.2551,022
129244.2.0.0/22244.2.0.1 to 244.2.3.254244.2.3.2551,022
130244.2.4.0/22244.2.4.1 to 244.2.7.254244.2.7.2551,022
131244.2.8.0/22244.2.8.1 to 244.2.11.254244.2.11.2551,022
132244.2.12.0/22244.2.12.1 to 244.2.15.254244.2.15.2551,022
133244.2.16.0/22244.2.16.1 to 244.2.19.254244.2.19.2551,022
134244.2.20.0/22244.2.20.1 to 244.2.23.254244.2.23.2551,022
135244.2.24.0/22244.2.24.1 to 244.2.27.254244.2.27.2551,022
136244.2.28.0/22244.2.28.1 to 244.2.31.254244.2.31.2551,022
137244.2.32.0/22244.2.32.1 to 244.2.35.254244.2.35.2551,022
138244.2.36.0/22244.2.36.1 to 244.2.39.254244.2.39.2551,022
139244.2.40.0/22244.2.40.1 to 244.2.43.254244.2.43.2551,022
140244.2.44.0/22244.2.44.1 to 244.2.47.254244.2.47.2551,022
141244.2.48.0/22244.2.48.1 to 244.2.51.254244.2.51.2551,022
142244.2.52.0/22244.2.52.1 to 244.2.55.254244.2.55.2551,022
143244.2.56.0/22244.2.56.1 to 244.2.59.254244.2.59.2551,022
144244.2.60.0/22244.2.60.1 to 244.2.63.254244.2.63.2551,022
145244.2.64.0/22244.2.64.1 to 244.2.67.254244.2.67.2551,022
146244.2.68.0/22244.2.68.1 to 244.2.71.254244.2.71.2551,022
147244.2.72.0/22244.2.72.1 to 244.2.75.254244.2.75.2551,022
148244.2.76.0/22244.2.76.1 to 244.2.79.254244.2.79.2551,022
149244.2.80.0/22244.2.80.1 to 244.2.83.254244.2.83.2551,022
150244.2.84.0/22244.2.84.1 to 244.2.87.254244.2.87.2551,022
151244.2.88.0/22244.2.88.1 to 244.2.91.254244.2.91.2551,022
152244.2.92.0/22244.2.92.1 to 244.2.95.254244.2.95.2551,022
153244.2.96.0/22244.2.96.1 to 244.2.99.254244.2.99.2551,022
154244.2.100.0/22244.2.100.1 to 244.2.103.254244.2.103.2551,022
155244.2.104.0/22244.2.104.1 to 244.2.107.254244.2.107.2551,022
156244.2.108.0/22244.2.108.1 to 244.2.111.254244.2.111.2551,022
157244.2.112.0/22244.2.112.1 to 244.2.115.254244.2.115.2551,022
158244.2.116.0/22244.2.116.1 to 244.2.119.254244.2.119.2551,022
159244.2.120.0/22244.2.120.1 to 244.2.123.254244.2.123.2551,022
160244.2.124.0/22244.2.124.1 to 244.2.127.254244.2.127.2551,022
161244.2.128.0/22244.2.128.1 to 244.2.131.254244.2.131.2551,022
162244.2.132.0/22244.2.132.1 to 244.2.135.254244.2.135.2551,022
163244.2.136.0/22244.2.136.1 to 244.2.139.254244.2.139.2551,022
164244.2.140.0/22244.2.140.1 to 244.2.143.254244.2.143.2551,022
165244.2.144.0/22244.2.144.1 to 244.2.147.254244.2.147.2551,022
166244.2.148.0/22244.2.148.1 to 244.2.151.254244.2.151.2551,022
167244.2.152.0/22244.2.152.1 to 244.2.155.254244.2.155.2551,022
168244.2.156.0/22244.2.156.1 to 244.2.159.254244.2.159.2551,022
169244.2.160.0/22244.2.160.1 to 244.2.163.254244.2.163.2551,022
170244.2.164.0/22244.2.164.1 to 244.2.167.254244.2.167.2551,022
171244.2.168.0/22244.2.168.1 to 244.2.171.254244.2.171.2551,022
172244.2.172.0/22244.2.172.1 to 244.2.175.254244.2.175.2551,022
173244.2.176.0/22244.2.176.1 to 244.2.179.254244.2.179.2551,022
174244.2.180.0/22244.2.180.1 to 244.2.183.254244.2.183.2551,022
175244.2.184.0/22244.2.184.1 to 244.2.187.254244.2.187.2551,022
176244.2.188.0/22244.2.188.1 to 244.2.191.254244.2.191.2551,022
177244.2.192.0/22244.2.192.1 to 244.2.195.254244.2.195.2551,022
178244.2.196.0/22244.2.196.1 to 244.2.199.254244.2.199.2551,022
179244.2.200.0/22244.2.200.1 to 244.2.203.254244.2.203.2551,022
180244.2.204.0/22244.2.204.1 to 244.2.207.254244.2.207.2551,022
181244.2.208.0/22244.2.208.1 to 244.2.211.254244.2.211.2551,022
182244.2.212.0/22244.2.212.1 to 244.2.215.254244.2.215.2551,022
183244.2.216.0/22244.2.216.1 to 244.2.219.254244.2.219.2551,022
184244.2.220.0/22244.2.220.1 to 244.2.223.254244.2.223.2551,022
185244.2.224.0/22244.2.224.1 to 244.2.227.254244.2.227.2551,022
186244.2.228.0/22244.2.228.1 to 244.2.231.254244.2.231.2551,022
187244.2.232.0/22244.2.232.1 to 244.2.235.254244.2.235.2551,022
188244.2.236.0/22244.2.236.1 to 244.2.239.254244.2.239.2551,022
189244.2.240.0/22244.2.240.1 to 244.2.243.254244.2.243.2551,022
190244.2.244.0/22244.2.244.1 to 244.2.247.254244.2.247.2551,022
191244.2.248.0/22244.2.248.1 to 244.2.251.254244.2.251.2551,022
192244.2.252.0/22244.2.252.1 to 244.2.255.254244.2.255.2551,022
193244.3.0.0/22244.3.0.1 to 244.3.3.254244.3.3.2551,022
194244.3.4.0/22244.3.4.1 to 244.3.7.254244.3.7.2551,022
195244.3.8.0/22244.3.8.1 to 244.3.11.254244.3.11.2551,022
196244.3.12.0/22244.3.12.1 to 244.3.15.254244.3.15.2551,022
197244.3.16.0/22244.3.16.1 to 244.3.19.254244.3.19.2551,022
198244.3.20.0/22244.3.20.1 to 244.3.23.254244.3.23.2551,022
199244.3.24.0/22244.3.24.1 to 244.3.27.254244.3.27.2551,022
200244.3.28.0/22244.3.28.1 to 244.3.31.254244.3.31.2551,022
201244.3.32.0/22244.3.32.1 to 244.3.35.254244.3.35.2551,022
202244.3.36.0/22244.3.36.1 to 244.3.39.254244.3.39.2551,022
203244.3.40.0/22244.3.40.1 to 244.3.43.254244.3.43.2551,022
204244.3.44.0/22244.3.44.1 to 244.3.47.254244.3.47.2551,022
205244.3.48.0/22244.3.48.1 to 244.3.51.254244.3.51.2551,022
206244.3.52.0/22244.3.52.1 to 244.3.55.254244.3.55.2551,022
207244.3.56.0/22244.3.56.1 to 244.3.59.254244.3.59.2551,022
208244.3.60.0/22244.3.60.1 to 244.3.63.254244.3.63.2551,022
209244.3.64.0/22244.3.64.1 to 244.3.67.254244.3.67.2551,022
210244.3.68.0/22244.3.68.1 to 244.3.71.254244.3.71.2551,022
211244.3.72.0/22244.3.72.1 to 244.3.75.254244.3.75.2551,022
212244.3.76.0/22244.3.76.1 to 244.3.79.254244.3.79.2551,022
213244.3.80.0/22244.3.80.1 to 244.3.83.254244.3.83.2551,022
214244.3.84.0/22244.3.84.1 to 244.3.87.254244.3.87.2551,022
215244.3.88.0/22244.3.88.1 to 244.3.91.254244.3.91.2551,022
216244.3.92.0/22244.3.92.1 to 244.3.95.254244.3.95.2551,022
217244.3.96.0/22244.3.96.1 to 244.3.99.254244.3.99.2551,022
218244.3.100.0/22244.3.100.1 to 244.3.103.254244.3.103.2551,022
219244.3.104.0/22244.3.104.1 to 244.3.107.254244.3.107.2551,022
220244.3.108.0/22244.3.108.1 to 244.3.111.254244.3.111.2551,022
221244.3.112.0/22244.3.112.1 to 244.3.115.254244.3.115.2551,022
222244.3.116.0/22244.3.116.1 to 244.3.119.254244.3.119.2551,022
223244.3.120.0/22244.3.120.1 to 244.3.123.254244.3.123.2551,022
224244.3.124.0/22244.3.124.1 to 244.3.127.254244.3.127.2551,022
225244.3.128.0/22244.3.128.1 to 244.3.131.254244.3.131.2551,022
226244.3.132.0/22244.3.132.1 to 244.3.135.254244.3.135.2551,022
227244.3.136.0/22244.3.136.1 to 244.3.139.254244.3.139.2551,022
228244.3.140.0/22244.3.140.1 to 244.3.143.254244.3.143.2551,022
229244.3.144.0/22244.3.144.1 to 244.3.147.254244.3.147.2551,022
230244.3.148.0/22244.3.148.1 to 244.3.151.254244.3.151.2551,022
231244.3.152.0/22244.3.152.1 to 244.3.155.254244.3.155.2551,022
232244.3.156.0/22244.3.156.1 to 244.3.159.254244.3.159.2551,022
233244.3.160.0/22244.3.160.1 to 244.3.163.254244.3.163.2551,022
234244.3.164.0/22244.3.164.1 to 244.3.167.254244.3.167.2551,022
235244.3.168.0/22244.3.168.1 to 244.3.171.254244.3.171.2551,022
236244.3.172.0/22244.3.172.1 to 244.3.175.254244.3.175.2551,022
237244.3.176.0/22244.3.176.1 to 244.3.179.254244.3.179.2551,022
238244.3.180.0/22244.3.180.1 to 244.3.183.254244.3.183.2551,022
239244.3.184.0/22244.3.184.1 to 244.3.187.254244.3.187.2551,022
240244.3.188.0/22244.3.188.1 to 244.3.191.254244.3.191.2551,022
241244.3.192.0/22244.3.192.1 to 244.3.195.254244.3.195.2551,022
242244.3.196.0/22244.3.196.1 to 244.3.199.254244.3.199.2551,022
243244.3.200.0/22244.3.200.1 to 244.3.203.254244.3.203.2551,022
244244.3.204.0/22244.3.204.1 to 244.3.207.254244.3.207.2551,022
245244.3.208.0/22244.3.208.1 to 244.3.211.254244.3.211.2551,022
246244.3.212.0/22244.3.212.1 to 244.3.215.254244.3.215.2551,022
247244.3.216.0/22244.3.216.1 to 244.3.219.254244.3.219.2551,022
248244.3.220.0/22244.3.220.1 to 244.3.223.254244.3.223.2551,022
249244.3.224.0/22244.3.224.1 to 244.3.227.254244.3.227.2551,022
250244.3.228.0/22244.3.228.1 to 244.3.231.254244.3.231.2551,022
251244.3.232.0/22244.3.232.1 to 244.3.235.254244.3.235.2551,022
252244.3.236.0/22244.3.236.1 to 244.3.239.254244.3.239.2551,022
253244.3.240.0/22244.3.240.1 to 244.3.243.254244.3.243.2551,022
254244.3.244.0/22244.3.244.1 to 244.3.247.254244.3.247.2551,022
255244.3.248.0/22244.3.248.1 to 244.3.251.254244.3.251.2551,022
256244.3.252.0/22244.3.252.1 to 244.3.255.254244.3.255.2551,022

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.