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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.

Network196.0.0.0/6
Usable hosts67,108,862
Subnet mask252.0.0.0
Addresses67,108,864
Network address
196.0.0.0
Broadcast address
199.255.255.255
First usable
196.0.0.1
Last usable
199.255.255.254
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 C4000000 · Integer 3288334336 to 3355443199
Reverse DNS zones
196.in-addr.arpa
197.in-addr.arpa
198.in-addr.arpa
199.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
Address11000100.00000000.00000000.00000000196.0.0.0
Subnet mask11111100.00000000.00000000.00000000252.0.0.0
Network11000100.00000000.00000000.00000000196.0.0.0
Broadcast11000111.11111111.11111111.11111111199.255.255.255
Split into smaller subnets/16
/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)

196.0.0.0/6 makes 1,024 subnets of /16; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
1196.0.0.0/16196.0.0.1 to 196.0.255.254196.0.255.25565,534
2196.1.0.0/16196.1.0.1 to 196.1.255.254196.1.255.25565,534
3196.2.0.0/16196.2.0.1 to 196.2.255.254196.2.255.25565,534
4196.3.0.0/16196.3.0.1 to 196.3.255.254196.3.255.25565,534
5196.4.0.0/16196.4.0.1 to 196.4.255.254196.4.255.25565,534
6196.5.0.0/16196.5.0.1 to 196.5.255.254196.5.255.25565,534
7196.6.0.0/16196.6.0.1 to 196.6.255.254196.6.255.25565,534
8196.7.0.0/16196.7.0.1 to 196.7.255.254196.7.255.25565,534
9196.8.0.0/16196.8.0.1 to 196.8.255.254196.8.255.25565,534
10196.9.0.0/16196.9.0.1 to 196.9.255.254196.9.255.25565,534
11196.10.0.0/16196.10.0.1 to 196.10.255.254196.10.255.25565,534
12196.11.0.0/16196.11.0.1 to 196.11.255.254196.11.255.25565,534
13196.12.0.0/16196.12.0.1 to 196.12.255.254196.12.255.25565,534
14196.13.0.0/16196.13.0.1 to 196.13.255.254196.13.255.25565,534
15196.14.0.0/16196.14.0.1 to 196.14.255.254196.14.255.25565,534
16196.15.0.0/16196.15.0.1 to 196.15.255.254196.15.255.25565,534
17196.16.0.0/16196.16.0.1 to 196.16.255.254196.16.255.25565,534
18196.17.0.0/16196.17.0.1 to 196.17.255.254196.17.255.25565,534
19196.18.0.0/16196.18.0.1 to 196.18.255.254196.18.255.25565,534
20196.19.0.0/16196.19.0.1 to 196.19.255.254196.19.255.25565,534
21196.20.0.0/16196.20.0.1 to 196.20.255.254196.20.255.25565,534
22196.21.0.0/16196.21.0.1 to 196.21.255.254196.21.255.25565,534
23196.22.0.0/16196.22.0.1 to 196.22.255.254196.22.255.25565,534
24196.23.0.0/16196.23.0.1 to 196.23.255.254196.23.255.25565,534
25196.24.0.0/16196.24.0.1 to 196.24.255.254196.24.255.25565,534
26196.25.0.0/16196.25.0.1 to 196.25.255.254196.25.255.25565,534
27196.26.0.0/16196.26.0.1 to 196.26.255.254196.26.255.25565,534
28196.27.0.0/16196.27.0.1 to 196.27.255.254196.27.255.25565,534
29196.28.0.0/16196.28.0.1 to 196.28.255.254196.28.255.25565,534
30196.29.0.0/16196.29.0.1 to 196.29.255.254196.29.255.25565,534
31196.30.0.0/16196.30.0.1 to 196.30.255.254196.30.255.25565,534
32196.31.0.0/16196.31.0.1 to 196.31.255.254196.31.255.25565,534
33196.32.0.0/16196.32.0.1 to 196.32.255.254196.32.255.25565,534
34196.33.0.0/16196.33.0.1 to 196.33.255.254196.33.255.25565,534
35196.34.0.0/16196.34.0.1 to 196.34.255.254196.34.255.25565,534
36196.35.0.0/16196.35.0.1 to 196.35.255.254196.35.255.25565,534
37196.36.0.0/16196.36.0.1 to 196.36.255.254196.36.255.25565,534
38196.37.0.0/16196.37.0.1 to 196.37.255.254196.37.255.25565,534
39196.38.0.0/16196.38.0.1 to 196.38.255.254196.38.255.25565,534
40196.39.0.0/16196.39.0.1 to 196.39.255.254196.39.255.25565,534
41196.40.0.0/16196.40.0.1 to 196.40.255.254196.40.255.25565,534
42196.41.0.0/16196.41.0.1 to 196.41.255.254196.41.255.25565,534
43196.42.0.0/16196.42.0.1 to 196.42.255.254196.42.255.25565,534
44196.43.0.0/16196.43.0.1 to 196.43.255.254196.43.255.25565,534
45196.44.0.0/16196.44.0.1 to 196.44.255.254196.44.255.25565,534
46196.45.0.0/16196.45.0.1 to 196.45.255.254196.45.255.25565,534
47196.46.0.0/16196.46.0.1 to 196.46.255.254196.46.255.25565,534
48196.47.0.0/16196.47.0.1 to 196.47.255.254196.47.255.25565,534
49196.48.0.0/16196.48.0.1 to 196.48.255.254196.48.255.25565,534
50196.49.0.0/16196.49.0.1 to 196.49.255.254196.49.255.25565,534
51196.50.0.0/16196.50.0.1 to 196.50.255.254196.50.255.25565,534
52196.51.0.0/16196.51.0.1 to 196.51.255.254196.51.255.25565,534
53196.52.0.0/16196.52.0.1 to 196.52.255.254196.52.255.25565,534
54196.53.0.0/16196.53.0.1 to 196.53.255.254196.53.255.25565,534
55196.54.0.0/16196.54.0.1 to 196.54.255.254196.54.255.25565,534
56196.55.0.0/16196.55.0.1 to 196.55.255.254196.55.255.25565,534
57196.56.0.0/16196.56.0.1 to 196.56.255.254196.56.255.25565,534
58196.57.0.0/16196.57.0.1 to 196.57.255.254196.57.255.25565,534
59196.58.0.0/16196.58.0.1 to 196.58.255.254196.58.255.25565,534
60196.59.0.0/16196.59.0.1 to 196.59.255.254196.59.255.25565,534
61196.60.0.0/16196.60.0.1 to 196.60.255.254196.60.255.25565,534
62196.61.0.0/16196.61.0.1 to 196.61.255.254196.61.255.25565,534
63196.62.0.0/16196.62.0.1 to 196.62.255.254196.62.255.25565,534
64196.63.0.0/16196.63.0.1 to 196.63.255.254196.63.255.25565,534
65196.64.0.0/16196.64.0.1 to 196.64.255.254196.64.255.25565,534
66196.65.0.0/16196.65.0.1 to 196.65.255.254196.65.255.25565,534
67196.66.0.0/16196.66.0.1 to 196.66.255.254196.66.255.25565,534
68196.67.0.0/16196.67.0.1 to 196.67.255.254196.67.255.25565,534
69196.68.0.0/16196.68.0.1 to 196.68.255.254196.68.255.25565,534
70196.69.0.0/16196.69.0.1 to 196.69.255.254196.69.255.25565,534
71196.70.0.0/16196.70.0.1 to 196.70.255.254196.70.255.25565,534
72196.71.0.0/16196.71.0.1 to 196.71.255.254196.71.255.25565,534
73196.72.0.0/16196.72.0.1 to 196.72.255.254196.72.255.25565,534
74196.73.0.0/16196.73.0.1 to 196.73.255.254196.73.255.25565,534
75196.74.0.0/16196.74.0.1 to 196.74.255.254196.74.255.25565,534
76196.75.0.0/16196.75.0.1 to 196.75.255.254196.75.255.25565,534
77196.76.0.0/16196.76.0.1 to 196.76.255.254196.76.255.25565,534
78196.77.0.0/16196.77.0.1 to 196.77.255.254196.77.255.25565,534
79196.78.0.0/16196.78.0.1 to 196.78.255.254196.78.255.25565,534
80196.79.0.0/16196.79.0.1 to 196.79.255.254196.79.255.25565,534
81196.80.0.0/16196.80.0.1 to 196.80.255.254196.80.255.25565,534
82196.81.0.0/16196.81.0.1 to 196.81.255.254196.81.255.25565,534
83196.82.0.0/16196.82.0.1 to 196.82.255.254196.82.255.25565,534
84196.83.0.0/16196.83.0.1 to 196.83.255.254196.83.255.25565,534
85196.84.0.0/16196.84.0.1 to 196.84.255.254196.84.255.25565,534
86196.85.0.0/16196.85.0.1 to 196.85.255.254196.85.255.25565,534
87196.86.0.0/16196.86.0.1 to 196.86.255.254196.86.255.25565,534
88196.87.0.0/16196.87.0.1 to 196.87.255.254196.87.255.25565,534
89196.88.0.0/16196.88.0.1 to 196.88.255.254196.88.255.25565,534
90196.89.0.0/16196.89.0.1 to 196.89.255.254196.89.255.25565,534
91196.90.0.0/16196.90.0.1 to 196.90.255.254196.90.255.25565,534
92196.91.0.0/16196.91.0.1 to 196.91.255.254196.91.255.25565,534
93196.92.0.0/16196.92.0.1 to 196.92.255.254196.92.255.25565,534
94196.93.0.0/16196.93.0.1 to 196.93.255.254196.93.255.25565,534
95196.94.0.0/16196.94.0.1 to 196.94.255.254196.94.255.25565,534
96196.95.0.0/16196.95.0.1 to 196.95.255.254196.95.255.25565,534
97196.96.0.0/16196.96.0.1 to 196.96.255.254196.96.255.25565,534
98196.97.0.0/16196.97.0.1 to 196.97.255.254196.97.255.25565,534
99196.98.0.0/16196.98.0.1 to 196.98.255.254196.98.255.25565,534
100196.99.0.0/16196.99.0.1 to 196.99.255.254196.99.255.25565,534
101196.100.0.0/16196.100.0.1 to 196.100.255.254196.100.255.25565,534
102196.101.0.0/16196.101.0.1 to 196.101.255.254196.101.255.25565,534
103196.102.0.0/16196.102.0.1 to 196.102.255.254196.102.255.25565,534
104196.103.0.0/16196.103.0.1 to 196.103.255.254196.103.255.25565,534
105196.104.0.0/16196.104.0.1 to 196.104.255.254196.104.255.25565,534
106196.105.0.0/16196.105.0.1 to 196.105.255.254196.105.255.25565,534
107196.106.0.0/16196.106.0.1 to 196.106.255.254196.106.255.25565,534
108196.107.0.0/16196.107.0.1 to 196.107.255.254196.107.255.25565,534
109196.108.0.0/16196.108.0.1 to 196.108.255.254196.108.255.25565,534
110196.109.0.0/16196.109.0.1 to 196.109.255.254196.109.255.25565,534
111196.110.0.0/16196.110.0.1 to 196.110.255.254196.110.255.25565,534
112196.111.0.0/16196.111.0.1 to 196.111.255.254196.111.255.25565,534
113196.112.0.0/16196.112.0.1 to 196.112.255.254196.112.255.25565,534
114196.113.0.0/16196.113.0.1 to 196.113.255.254196.113.255.25565,534
115196.114.0.0/16196.114.0.1 to 196.114.255.254196.114.255.25565,534
116196.115.0.0/16196.115.0.1 to 196.115.255.254196.115.255.25565,534
117196.116.0.0/16196.116.0.1 to 196.116.255.254196.116.255.25565,534
118196.117.0.0/16196.117.0.1 to 196.117.255.254196.117.255.25565,534
119196.118.0.0/16196.118.0.1 to 196.118.255.254196.118.255.25565,534
120196.119.0.0/16196.119.0.1 to 196.119.255.254196.119.255.25565,534
121196.120.0.0/16196.120.0.1 to 196.120.255.254196.120.255.25565,534
122196.121.0.0/16196.121.0.1 to 196.121.255.254196.121.255.25565,534
123196.122.0.0/16196.122.0.1 to 196.122.255.254196.122.255.25565,534
124196.123.0.0/16196.123.0.1 to 196.123.255.254196.123.255.25565,534
125196.124.0.0/16196.124.0.1 to 196.124.255.254196.124.255.25565,534
126196.125.0.0/16196.125.0.1 to 196.125.255.254196.125.255.25565,534
127196.126.0.0/16196.126.0.1 to 196.126.255.254196.126.255.25565,534
128196.127.0.0/16196.127.0.1 to 196.127.255.254196.127.255.25565,534
129196.128.0.0/16196.128.0.1 to 196.128.255.254196.128.255.25565,534
130196.129.0.0/16196.129.0.1 to 196.129.255.254196.129.255.25565,534
131196.130.0.0/16196.130.0.1 to 196.130.255.254196.130.255.25565,534
132196.131.0.0/16196.131.0.1 to 196.131.255.254196.131.255.25565,534
133196.132.0.0/16196.132.0.1 to 196.132.255.254196.132.255.25565,534
134196.133.0.0/16196.133.0.1 to 196.133.255.254196.133.255.25565,534
135196.134.0.0/16196.134.0.1 to 196.134.255.254196.134.255.25565,534
136196.135.0.0/16196.135.0.1 to 196.135.255.254196.135.255.25565,534
137196.136.0.0/16196.136.0.1 to 196.136.255.254196.136.255.25565,534
138196.137.0.0/16196.137.0.1 to 196.137.255.254196.137.255.25565,534
139196.138.0.0/16196.138.0.1 to 196.138.255.254196.138.255.25565,534
140196.139.0.0/16196.139.0.1 to 196.139.255.254196.139.255.25565,534
141196.140.0.0/16196.140.0.1 to 196.140.255.254196.140.255.25565,534
142196.141.0.0/16196.141.0.1 to 196.141.255.254196.141.255.25565,534
143196.142.0.0/16196.142.0.1 to 196.142.255.254196.142.255.25565,534
144196.143.0.0/16196.143.0.1 to 196.143.255.254196.143.255.25565,534
145196.144.0.0/16196.144.0.1 to 196.144.255.254196.144.255.25565,534
146196.145.0.0/16196.145.0.1 to 196.145.255.254196.145.255.25565,534
147196.146.0.0/16196.146.0.1 to 196.146.255.254196.146.255.25565,534
148196.147.0.0/16196.147.0.1 to 196.147.255.254196.147.255.25565,534
149196.148.0.0/16196.148.0.1 to 196.148.255.254196.148.255.25565,534
150196.149.0.0/16196.149.0.1 to 196.149.255.254196.149.255.25565,534
151196.150.0.0/16196.150.0.1 to 196.150.255.254196.150.255.25565,534
152196.151.0.0/16196.151.0.1 to 196.151.255.254196.151.255.25565,534
153196.152.0.0/16196.152.0.1 to 196.152.255.254196.152.255.25565,534
154196.153.0.0/16196.153.0.1 to 196.153.255.254196.153.255.25565,534
155196.154.0.0/16196.154.0.1 to 196.154.255.254196.154.255.25565,534
156196.155.0.0/16196.155.0.1 to 196.155.255.254196.155.255.25565,534
157196.156.0.0/16196.156.0.1 to 196.156.255.254196.156.255.25565,534
158196.157.0.0/16196.157.0.1 to 196.157.255.254196.157.255.25565,534
159196.158.0.0/16196.158.0.1 to 196.158.255.254196.158.255.25565,534
160196.159.0.0/16196.159.0.1 to 196.159.255.254196.159.255.25565,534
161196.160.0.0/16196.160.0.1 to 196.160.255.254196.160.255.25565,534
162196.161.0.0/16196.161.0.1 to 196.161.255.254196.161.255.25565,534
163196.162.0.0/16196.162.0.1 to 196.162.255.254196.162.255.25565,534
164196.163.0.0/16196.163.0.1 to 196.163.255.254196.163.255.25565,534
165196.164.0.0/16196.164.0.1 to 196.164.255.254196.164.255.25565,534
166196.165.0.0/16196.165.0.1 to 196.165.255.254196.165.255.25565,534
167196.166.0.0/16196.166.0.1 to 196.166.255.254196.166.255.25565,534
168196.167.0.0/16196.167.0.1 to 196.167.255.254196.167.255.25565,534
169196.168.0.0/16196.168.0.1 to 196.168.255.254196.168.255.25565,534
170196.169.0.0/16196.169.0.1 to 196.169.255.254196.169.255.25565,534
171196.170.0.0/16196.170.0.1 to 196.170.255.254196.170.255.25565,534
172196.171.0.0/16196.171.0.1 to 196.171.255.254196.171.255.25565,534
173196.172.0.0/16196.172.0.1 to 196.172.255.254196.172.255.25565,534
174196.173.0.0/16196.173.0.1 to 196.173.255.254196.173.255.25565,534
175196.174.0.0/16196.174.0.1 to 196.174.255.254196.174.255.25565,534
176196.175.0.0/16196.175.0.1 to 196.175.255.254196.175.255.25565,534
177196.176.0.0/16196.176.0.1 to 196.176.255.254196.176.255.25565,534
178196.177.0.0/16196.177.0.1 to 196.177.255.254196.177.255.25565,534
179196.178.0.0/16196.178.0.1 to 196.178.255.254196.178.255.25565,534
180196.179.0.0/16196.179.0.1 to 196.179.255.254196.179.255.25565,534
181196.180.0.0/16196.180.0.1 to 196.180.255.254196.180.255.25565,534
182196.181.0.0/16196.181.0.1 to 196.181.255.254196.181.255.25565,534
183196.182.0.0/16196.182.0.1 to 196.182.255.254196.182.255.25565,534
184196.183.0.0/16196.183.0.1 to 196.183.255.254196.183.255.25565,534
185196.184.0.0/16196.184.0.1 to 196.184.255.254196.184.255.25565,534
186196.185.0.0/16196.185.0.1 to 196.185.255.254196.185.255.25565,534
187196.186.0.0/16196.186.0.1 to 196.186.255.254196.186.255.25565,534
188196.187.0.0/16196.187.0.1 to 196.187.255.254196.187.255.25565,534
189196.188.0.0/16196.188.0.1 to 196.188.255.254196.188.255.25565,534
190196.189.0.0/16196.189.0.1 to 196.189.255.254196.189.255.25565,534
191196.190.0.0/16196.190.0.1 to 196.190.255.254196.190.255.25565,534
192196.191.0.0/16196.191.0.1 to 196.191.255.254196.191.255.25565,534
193196.192.0.0/16196.192.0.1 to 196.192.255.254196.192.255.25565,534
194196.193.0.0/16196.193.0.1 to 196.193.255.254196.193.255.25565,534
195196.194.0.0/16196.194.0.1 to 196.194.255.254196.194.255.25565,534
196196.195.0.0/16196.195.0.1 to 196.195.255.254196.195.255.25565,534
197196.196.0.0/16196.196.0.1 to 196.196.255.254196.196.255.25565,534
198196.197.0.0/16196.197.0.1 to 196.197.255.254196.197.255.25565,534
199196.198.0.0/16196.198.0.1 to 196.198.255.254196.198.255.25565,534
200196.199.0.0/16196.199.0.1 to 196.199.255.254196.199.255.25565,534
201196.200.0.0/16196.200.0.1 to 196.200.255.254196.200.255.25565,534
202196.201.0.0/16196.201.0.1 to 196.201.255.254196.201.255.25565,534
203196.202.0.0/16196.202.0.1 to 196.202.255.254196.202.255.25565,534
204196.203.0.0/16196.203.0.1 to 196.203.255.254196.203.255.25565,534
205196.204.0.0/16196.204.0.1 to 196.204.255.254196.204.255.25565,534
206196.205.0.0/16196.205.0.1 to 196.205.255.254196.205.255.25565,534
207196.206.0.0/16196.206.0.1 to 196.206.255.254196.206.255.25565,534
208196.207.0.0/16196.207.0.1 to 196.207.255.254196.207.255.25565,534
209196.208.0.0/16196.208.0.1 to 196.208.255.254196.208.255.25565,534
210196.209.0.0/16196.209.0.1 to 196.209.255.254196.209.255.25565,534
211196.210.0.0/16196.210.0.1 to 196.210.255.254196.210.255.25565,534
212196.211.0.0/16196.211.0.1 to 196.211.255.254196.211.255.25565,534
213196.212.0.0/16196.212.0.1 to 196.212.255.254196.212.255.25565,534
214196.213.0.0/16196.213.0.1 to 196.213.255.254196.213.255.25565,534
215196.214.0.0/16196.214.0.1 to 196.214.255.254196.214.255.25565,534
216196.215.0.0/16196.215.0.1 to 196.215.255.254196.215.255.25565,534
217196.216.0.0/16196.216.0.1 to 196.216.255.254196.216.255.25565,534
218196.217.0.0/16196.217.0.1 to 196.217.255.254196.217.255.25565,534
219196.218.0.0/16196.218.0.1 to 196.218.255.254196.218.255.25565,534
220196.219.0.0/16196.219.0.1 to 196.219.255.254196.219.255.25565,534
221196.220.0.0/16196.220.0.1 to 196.220.255.254196.220.255.25565,534
222196.221.0.0/16196.221.0.1 to 196.221.255.254196.221.255.25565,534
223196.222.0.0/16196.222.0.1 to 196.222.255.254196.222.255.25565,534
224196.223.0.0/16196.223.0.1 to 196.223.255.254196.223.255.25565,534
225196.224.0.0/16196.224.0.1 to 196.224.255.254196.224.255.25565,534
226196.225.0.0/16196.225.0.1 to 196.225.255.254196.225.255.25565,534
227196.226.0.0/16196.226.0.1 to 196.226.255.254196.226.255.25565,534
228196.227.0.0/16196.227.0.1 to 196.227.255.254196.227.255.25565,534
229196.228.0.0/16196.228.0.1 to 196.228.255.254196.228.255.25565,534
230196.229.0.0/16196.229.0.1 to 196.229.255.254196.229.255.25565,534
231196.230.0.0/16196.230.0.1 to 196.230.255.254196.230.255.25565,534
232196.231.0.0/16196.231.0.1 to 196.231.255.254196.231.255.25565,534
233196.232.0.0/16196.232.0.1 to 196.232.255.254196.232.255.25565,534
234196.233.0.0/16196.233.0.1 to 196.233.255.254196.233.255.25565,534
235196.234.0.0/16196.234.0.1 to 196.234.255.254196.234.255.25565,534
236196.235.0.0/16196.235.0.1 to 196.235.255.254196.235.255.25565,534
237196.236.0.0/16196.236.0.1 to 196.236.255.254196.236.255.25565,534
238196.237.0.0/16196.237.0.1 to 196.237.255.254196.237.255.25565,534
239196.238.0.0/16196.238.0.1 to 196.238.255.254196.238.255.25565,534
240196.239.0.0/16196.239.0.1 to 196.239.255.254196.239.255.25565,534
241196.240.0.0/16196.240.0.1 to 196.240.255.254196.240.255.25565,534
242196.241.0.0/16196.241.0.1 to 196.241.255.254196.241.255.25565,534
243196.242.0.0/16196.242.0.1 to 196.242.255.254196.242.255.25565,534
244196.243.0.0/16196.243.0.1 to 196.243.255.254196.243.255.25565,534
245196.244.0.0/16196.244.0.1 to 196.244.255.254196.244.255.25565,534
246196.245.0.0/16196.245.0.1 to 196.245.255.254196.245.255.25565,534
247196.246.0.0/16196.246.0.1 to 196.246.255.254196.246.255.25565,534
248196.247.0.0/16196.247.0.1 to 196.247.255.254196.247.255.25565,534
249196.248.0.0/16196.248.0.1 to 196.248.255.254196.248.255.25565,534
250196.249.0.0/16196.249.0.1 to 196.249.255.254196.249.255.25565,534
251196.250.0.0/16196.250.0.1 to 196.250.255.254196.250.255.25565,534
252196.251.0.0/16196.251.0.1 to 196.251.255.254196.251.255.25565,534
253196.252.0.0/16196.252.0.1 to 196.252.255.254196.252.255.25565,534
254196.253.0.0/16196.253.0.1 to 196.253.255.254196.253.255.25565,534
255196.254.0.0/16196.254.0.1 to 196.254.255.254196.254.255.25565,534
256196.255.0.0/16196.255.0.1 to 196.255.255.254196.255.255.25565,534

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.