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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.

Network196.0.0.0/7
Usable hosts33,554,430
Subnet mask254.0.0.0
Addresses33,554,432
Network address
196.0.0.0
Broadcast address
197.255.255.255
First usable
196.0.0.1
Last usable
197.255.255.254
Usable hosts
33,554,430 (33,554,432 less the network and broadcast addresses)
Subnet mask
254.0.0.0
Wildcard mask
1.255.255.255 (Cisco ACLs, OSPF)
Prefix length
/7
Type
Public public
Old class
C (default /24)
As numbers
Hex C4000000 · Integer 3288334336 to 3321888767
Reverse DNS zones
196.in-addr.arpa
197.in-addr.arpa
/7 is not on a 8-bit boundary, so it takes 2 /8 zones.
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address11000100.00000000.00000000.00000000196.0.0.0
Subnet mask11111110.00000000.00000000.00000000254.0.0.0
Network11000100.00000000.00000000.00000000196.0.0.0
Broadcast11000101.11111111.11111111.11111111197.255.255.255
Split into smaller subnets/15

196.0.0.0/7 makes 256 subnets of /15.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
1196.0.0.0/15196.0.0.1 to 196.1.255.254196.1.255.255131,070
2196.2.0.0/15196.2.0.1 to 196.3.255.254196.3.255.255131,070
3196.4.0.0/15196.4.0.1 to 196.5.255.254196.5.255.255131,070
4196.6.0.0/15196.6.0.1 to 196.7.255.254196.7.255.255131,070
5196.8.0.0/15196.8.0.1 to 196.9.255.254196.9.255.255131,070
6196.10.0.0/15196.10.0.1 to 196.11.255.254196.11.255.255131,070
7196.12.0.0/15196.12.0.1 to 196.13.255.254196.13.255.255131,070
8196.14.0.0/15196.14.0.1 to 196.15.255.254196.15.255.255131,070
9196.16.0.0/15196.16.0.1 to 196.17.255.254196.17.255.255131,070
10196.18.0.0/15196.18.0.1 to 196.19.255.254196.19.255.255131,070
11196.20.0.0/15196.20.0.1 to 196.21.255.254196.21.255.255131,070
12196.22.0.0/15196.22.0.1 to 196.23.255.254196.23.255.255131,070
13196.24.0.0/15196.24.0.1 to 196.25.255.254196.25.255.255131,070
14196.26.0.0/15196.26.0.1 to 196.27.255.254196.27.255.255131,070
15196.28.0.0/15196.28.0.1 to 196.29.255.254196.29.255.255131,070
16196.30.0.0/15196.30.0.1 to 196.31.255.254196.31.255.255131,070
17196.32.0.0/15196.32.0.1 to 196.33.255.254196.33.255.255131,070
18196.34.0.0/15196.34.0.1 to 196.35.255.254196.35.255.255131,070
19196.36.0.0/15196.36.0.1 to 196.37.255.254196.37.255.255131,070
20196.38.0.0/15196.38.0.1 to 196.39.255.254196.39.255.255131,070
21196.40.0.0/15196.40.0.1 to 196.41.255.254196.41.255.255131,070
22196.42.0.0/15196.42.0.1 to 196.43.255.254196.43.255.255131,070
23196.44.0.0/15196.44.0.1 to 196.45.255.254196.45.255.255131,070
24196.46.0.0/15196.46.0.1 to 196.47.255.254196.47.255.255131,070
25196.48.0.0/15196.48.0.1 to 196.49.255.254196.49.255.255131,070
26196.50.0.0/15196.50.0.1 to 196.51.255.254196.51.255.255131,070
27196.52.0.0/15196.52.0.1 to 196.53.255.254196.53.255.255131,070
28196.54.0.0/15196.54.0.1 to 196.55.255.254196.55.255.255131,070
29196.56.0.0/15196.56.0.1 to 196.57.255.254196.57.255.255131,070
30196.58.0.0/15196.58.0.1 to 196.59.255.254196.59.255.255131,070
31196.60.0.0/15196.60.0.1 to 196.61.255.254196.61.255.255131,070
32196.62.0.0/15196.62.0.1 to 196.63.255.254196.63.255.255131,070
33196.64.0.0/15196.64.0.1 to 196.65.255.254196.65.255.255131,070
34196.66.0.0/15196.66.0.1 to 196.67.255.254196.67.255.255131,070
35196.68.0.0/15196.68.0.1 to 196.69.255.254196.69.255.255131,070
36196.70.0.0/15196.70.0.1 to 196.71.255.254196.71.255.255131,070
37196.72.0.0/15196.72.0.1 to 196.73.255.254196.73.255.255131,070
38196.74.0.0/15196.74.0.1 to 196.75.255.254196.75.255.255131,070
39196.76.0.0/15196.76.0.1 to 196.77.255.254196.77.255.255131,070
40196.78.0.0/15196.78.0.1 to 196.79.255.254196.79.255.255131,070
41196.80.0.0/15196.80.0.1 to 196.81.255.254196.81.255.255131,070
42196.82.0.0/15196.82.0.1 to 196.83.255.254196.83.255.255131,070
43196.84.0.0/15196.84.0.1 to 196.85.255.254196.85.255.255131,070
44196.86.0.0/15196.86.0.1 to 196.87.255.254196.87.255.255131,070
45196.88.0.0/15196.88.0.1 to 196.89.255.254196.89.255.255131,070
46196.90.0.0/15196.90.0.1 to 196.91.255.254196.91.255.255131,070
47196.92.0.0/15196.92.0.1 to 196.93.255.254196.93.255.255131,070
48196.94.0.0/15196.94.0.1 to 196.95.255.254196.95.255.255131,070
49196.96.0.0/15196.96.0.1 to 196.97.255.254196.97.255.255131,070
50196.98.0.0/15196.98.0.1 to 196.99.255.254196.99.255.255131,070
51196.100.0.0/15196.100.0.1 to 196.101.255.254196.101.255.255131,070
52196.102.0.0/15196.102.0.1 to 196.103.255.254196.103.255.255131,070
53196.104.0.0/15196.104.0.1 to 196.105.255.254196.105.255.255131,070
54196.106.0.0/15196.106.0.1 to 196.107.255.254196.107.255.255131,070
55196.108.0.0/15196.108.0.1 to 196.109.255.254196.109.255.255131,070
56196.110.0.0/15196.110.0.1 to 196.111.255.254196.111.255.255131,070
57196.112.0.0/15196.112.0.1 to 196.113.255.254196.113.255.255131,070
58196.114.0.0/15196.114.0.1 to 196.115.255.254196.115.255.255131,070
59196.116.0.0/15196.116.0.1 to 196.117.255.254196.117.255.255131,070
60196.118.0.0/15196.118.0.1 to 196.119.255.254196.119.255.255131,070
61196.120.0.0/15196.120.0.1 to 196.121.255.254196.121.255.255131,070
62196.122.0.0/15196.122.0.1 to 196.123.255.254196.123.255.255131,070
63196.124.0.0/15196.124.0.1 to 196.125.255.254196.125.255.255131,070
64196.126.0.0/15196.126.0.1 to 196.127.255.254196.127.255.255131,070
65196.128.0.0/15196.128.0.1 to 196.129.255.254196.129.255.255131,070
66196.130.0.0/15196.130.0.1 to 196.131.255.254196.131.255.255131,070
67196.132.0.0/15196.132.0.1 to 196.133.255.254196.133.255.255131,070
68196.134.0.0/15196.134.0.1 to 196.135.255.254196.135.255.255131,070
69196.136.0.0/15196.136.0.1 to 196.137.255.254196.137.255.255131,070
70196.138.0.0/15196.138.0.1 to 196.139.255.254196.139.255.255131,070
71196.140.0.0/15196.140.0.1 to 196.141.255.254196.141.255.255131,070
72196.142.0.0/15196.142.0.1 to 196.143.255.254196.143.255.255131,070
73196.144.0.0/15196.144.0.1 to 196.145.255.254196.145.255.255131,070
74196.146.0.0/15196.146.0.1 to 196.147.255.254196.147.255.255131,070
75196.148.0.0/15196.148.0.1 to 196.149.255.254196.149.255.255131,070
76196.150.0.0/15196.150.0.1 to 196.151.255.254196.151.255.255131,070
77196.152.0.0/15196.152.0.1 to 196.153.255.254196.153.255.255131,070
78196.154.0.0/15196.154.0.1 to 196.155.255.254196.155.255.255131,070
79196.156.0.0/15196.156.0.1 to 196.157.255.254196.157.255.255131,070
80196.158.0.0/15196.158.0.1 to 196.159.255.254196.159.255.255131,070
81196.160.0.0/15196.160.0.1 to 196.161.255.254196.161.255.255131,070
82196.162.0.0/15196.162.0.1 to 196.163.255.254196.163.255.255131,070
83196.164.0.0/15196.164.0.1 to 196.165.255.254196.165.255.255131,070
84196.166.0.0/15196.166.0.1 to 196.167.255.254196.167.255.255131,070
85196.168.0.0/15196.168.0.1 to 196.169.255.254196.169.255.255131,070
86196.170.0.0/15196.170.0.1 to 196.171.255.254196.171.255.255131,070
87196.172.0.0/15196.172.0.1 to 196.173.255.254196.173.255.255131,070
88196.174.0.0/15196.174.0.1 to 196.175.255.254196.175.255.255131,070
89196.176.0.0/15196.176.0.1 to 196.177.255.254196.177.255.255131,070
90196.178.0.0/15196.178.0.1 to 196.179.255.254196.179.255.255131,070
91196.180.0.0/15196.180.0.1 to 196.181.255.254196.181.255.255131,070
92196.182.0.0/15196.182.0.1 to 196.183.255.254196.183.255.255131,070
93196.184.0.0/15196.184.0.1 to 196.185.255.254196.185.255.255131,070
94196.186.0.0/15196.186.0.1 to 196.187.255.254196.187.255.255131,070
95196.188.0.0/15196.188.0.1 to 196.189.255.254196.189.255.255131,070
96196.190.0.0/15196.190.0.1 to 196.191.255.254196.191.255.255131,070
97196.192.0.0/15196.192.0.1 to 196.193.255.254196.193.255.255131,070
98196.194.0.0/15196.194.0.1 to 196.195.255.254196.195.255.255131,070
99196.196.0.0/15196.196.0.1 to 196.197.255.254196.197.255.255131,070
100196.198.0.0/15196.198.0.1 to 196.199.255.254196.199.255.255131,070
101196.200.0.0/15196.200.0.1 to 196.201.255.254196.201.255.255131,070
102196.202.0.0/15196.202.0.1 to 196.203.255.254196.203.255.255131,070
103196.204.0.0/15196.204.0.1 to 196.205.255.254196.205.255.255131,070
104196.206.0.0/15196.206.0.1 to 196.207.255.254196.207.255.255131,070
105196.208.0.0/15196.208.0.1 to 196.209.255.254196.209.255.255131,070
106196.210.0.0/15196.210.0.1 to 196.211.255.254196.211.255.255131,070
107196.212.0.0/15196.212.0.1 to 196.213.255.254196.213.255.255131,070
108196.214.0.0/15196.214.0.1 to 196.215.255.254196.215.255.255131,070
109196.216.0.0/15196.216.0.1 to 196.217.255.254196.217.255.255131,070
110196.218.0.0/15196.218.0.1 to 196.219.255.254196.219.255.255131,070
111196.220.0.0/15196.220.0.1 to 196.221.255.254196.221.255.255131,070
112196.222.0.0/15196.222.0.1 to 196.223.255.254196.223.255.255131,070
113196.224.0.0/15196.224.0.1 to 196.225.255.254196.225.255.255131,070
114196.226.0.0/15196.226.0.1 to 196.227.255.254196.227.255.255131,070
115196.228.0.0/15196.228.0.1 to 196.229.255.254196.229.255.255131,070
116196.230.0.0/15196.230.0.1 to 196.231.255.254196.231.255.255131,070
117196.232.0.0/15196.232.0.1 to 196.233.255.254196.233.255.255131,070
118196.234.0.0/15196.234.0.1 to 196.235.255.254196.235.255.255131,070
119196.236.0.0/15196.236.0.1 to 196.237.255.254196.237.255.255131,070
120196.238.0.0/15196.238.0.1 to 196.239.255.254196.239.255.255131,070
121196.240.0.0/15196.240.0.1 to 196.241.255.254196.241.255.255131,070
122196.242.0.0/15196.242.0.1 to 196.243.255.254196.243.255.255131,070
123196.244.0.0/15196.244.0.1 to 196.245.255.254196.245.255.255131,070
124196.246.0.0/15196.246.0.1 to 196.247.255.254196.247.255.255131,070
125196.248.0.0/15196.248.0.1 to 196.249.255.254196.249.255.255131,070
126196.250.0.0/15196.250.0.1 to 196.251.255.254196.251.255.255131,070
127196.252.0.0/15196.252.0.1 to 196.253.255.254196.253.255.255131,070
128196.254.0.0/15196.254.0.1 to 196.255.255.254196.255.255.255131,070
129197.0.0.0/15197.0.0.1 to 197.1.255.254197.1.255.255131,070
130197.2.0.0/15197.2.0.1 to 197.3.255.254197.3.255.255131,070
131197.4.0.0/15197.4.0.1 to 197.5.255.254197.5.255.255131,070
132197.6.0.0/15197.6.0.1 to 197.7.255.254197.7.255.255131,070
133197.8.0.0/15197.8.0.1 to 197.9.255.254197.9.255.255131,070
134197.10.0.0/15197.10.0.1 to 197.11.255.254197.11.255.255131,070
135197.12.0.0/15197.12.0.1 to 197.13.255.254197.13.255.255131,070
136197.14.0.0/15197.14.0.1 to 197.15.255.254197.15.255.255131,070
137197.16.0.0/15197.16.0.1 to 197.17.255.254197.17.255.255131,070
138197.18.0.0/15197.18.0.1 to 197.19.255.254197.19.255.255131,070
139197.20.0.0/15197.20.0.1 to 197.21.255.254197.21.255.255131,070
140197.22.0.0/15197.22.0.1 to 197.23.255.254197.23.255.255131,070
141197.24.0.0/15197.24.0.1 to 197.25.255.254197.25.255.255131,070
142197.26.0.0/15197.26.0.1 to 197.27.255.254197.27.255.255131,070
143197.28.0.0/15197.28.0.1 to 197.29.255.254197.29.255.255131,070
144197.30.0.0/15197.30.0.1 to 197.31.255.254197.31.255.255131,070
145197.32.0.0/15197.32.0.1 to 197.33.255.254197.33.255.255131,070
146197.34.0.0/15197.34.0.1 to 197.35.255.254197.35.255.255131,070
147197.36.0.0/15197.36.0.1 to 197.37.255.254197.37.255.255131,070
148197.38.0.0/15197.38.0.1 to 197.39.255.254197.39.255.255131,070
149197.40.0.0/15197.40.0.1 to 197.41.255.254197.41.255.255131,070
150197.42.0.0/15197.42.0.1 to 197.43.255.254197.43.255.255131,070
151197.44.0.0/15197.44.0.1 to 197.45.255.254197.45.255.255131,070
152197.46.0.0/15197.46.0.1 to 197.47.255.254197.47.255.255131,070
153197.48.0.0/15197.48.0.1 to 197.49.255.254197.49.255.255131,070
154197.50.0.0/15197.50.0.1 to 197.51.255.254197.51.255.255131,070
155197.52.0.0/15197.52.0.1 to 197.53.255.254197.53.255.255131,070
156197.54.0.0/15197.54.0.1 to 197.55.255.254197.55.255.255131,070
157197.56.0.0/15197.56.0.1 to 197.57.255.254197.57.255.255131,070
158197.58.0.0/15197.58.0.1 to 197.59.255.254197.59.255.255131,070
159197.60.0.0/15197.60.0.1 to 197.61.255.254197.61.255.255131,070
160197.62.0.0/15197.62.0.1 to 197.63.255.254197.63.255.255131,070
161197.64.0.0/15197.64.0.1 to 197.65.255.254197.65.255.255131,070
162197.66.0.0/15197.66.0.1 to 197.67.255.254197.67.255.255131,070
163197.68.0.0/15197.68.0.1 to 197.69.255.254197.69.255.255131,070
164197.70.0.0/15197.70.0.1 to 197.71.255.254197.71.255.255131,070
165197.72.0.0/15197.72.0.1 to 197.73.255.254197.73.255.255131,070
166197.74.0.0/15197.74.0.1 to 197.75.255.254197.75.255.255131,070
167197.76.0.0/15197.76.0.1 to 197.77.255.254197.77.255.255131,070
168197.78.0.0/15197.78.0.1 to 197.79.255.254197.79.255.255131,070
169197.80.0.0/15197.80.0.1 to 197.81.255.254197.81.255.255131,070
170197.82.0.0/15197.82.0.1 to 197.83.255.254197.83.255.255131,070
171197.84.0.0/15197.84.0.1 to 197.85.255.254197.85.255.255131,070
172197.86.0.0/15197.86.0.1 to 197.87.255.254197.87.255.255131,070
173197.88.0.0/15197.88.0.1 to 197.89.255.254197.89.255.255131,070
174197.90.0.0/15197.90.0.1 to 197.91.255.254197.91.255.255131,070
175197.92.0.0/15197.92.0.1 to 197.93.255.254197.93.255.255131,070
176197.94.0.0/15197.94.0.1 to 197.95.255.254197.95.255.255131,070
177197.96.0.0/15197.96.0.1 to 197.97.255.254197.97.255.255131,070
178197.98.0.0/15197.98.0.1 to 197.99.255.254197.99.255.255131,070
179197.100.0.0/15197.100.0.1 to 197.101.255.254197.101.255.255131,070
180197.102.0.0/15197.102.0.1 to 197.103.255.254197.103.255.255131,070
181197.104.0.0/15197.104.0.1 to 197.105.255.254197.105.255.255131,070
182197.106.0.0/15197.106.0.1 to 197.107.255.254197.107.255.255131,070
183197.108.0.0/15197.108.0.1 to 197.109.255.254197.109.255.255131,070
184197.110.0.0/15197.110.0.1 to 197.111.255.254197.111.255.255131,070
185197.112.0.0/15197.112.0.1 to 197.113.255.254197.113.255.255131,070
186197.114.0.0/15197.114.0.1 to 197.115.255.254197.115.255.255131,070
187197.116.0.0/15197.116.0.1 to 197.117.255.254197.117.255.255131,070
188197.118.0.0/15197.118.0.1 to 197.119.255.254197.119.255.255131,070
189197.120.0.0/15197.120.0.1 to 197.121.255.254197.121.255.255131,070
190197.122.0.0/15197.122.0.1 to 197.123.255.254197.123.255.255131,070
191197.124.0.0/15197.124.0.1 to 197.125.255.254197.125.255.255131,070
192197.126.0.0/15197.126.0.1 to 197.127.255.254197.127.255.255131,070
193197.128.0.0/15197.128.0.1 to 197.129.255.254197.129.255.255131,070
194197.130.0.0/15197.130.0.1 to 197.131.255.254197.131.255.255131,070
195197.132.0.0/15197.132.0.1 to 197.133.255.254197.133.255.255131,070
196197.134.0.0/15197.134.0.1 to 197.135.255.254197.135.255.255131,070
197197.136.0.0/15197.136.0.1 to 197.137.255.254197.137.255.255131,070
198197.138.0.0/15197.138.0.1 to 197.139.255.254197.139.255.255131,070
199197.140.0.0/15197.140.0.1 to 197.141.255.254197.141.255.255131,070
200197.142.0.0/15197.142.0.1 to 197.143.255.254197.143.255.255131,070
201197.144.0.0/15197.144.0.1 to 197.145.255.254197.145.255.255131,070
202197.146.0.0/15197.146.0.1 to 197.147.255.254197.147.255.255131,070
203197.148.0.0/15197.148.0.1 to 197.149.255.254197.149.255.255131,070
204197.150.0.0/15197.150.0.1 to 197.151.255.254197.151.255.255131,070
205197.152.0.0/15197.152.0.1 to 197.153.255.254197.153.255.255131,070
206197.154.0.0/15197.154.0.1 to 197.155.255.254197.155.255.255131,070
207197.156.0.0/15197.156.0.1 to 197.157.255.254197.157.255.255131,070
208197.158.0.0/15197.158.0.1 to 197.159.255.254197.159.255.255131,070
209197.160.0.0/15197.160.0.1 to 197.161.255.254197.161.255.255131,070
210197.162.0.0/15197.162.0.1 to 197.163.255.254197.163.255.255131,070
211197.164.0.0/15197.164.0.1 to 197.165.255.254197.165.255.255131,070
212197.166.0.0/15197.166.0.1 to 197.167.255.254197.167.255.255131,070
213197.168.0.0/15197.168.0.1 to 197.169.255.254197.169.255.255131,070
214197.170.0.0/15197.170.0.1 to 197.171.255.254197.171.255.255131,070
215197.172.0.0/15197.172.0.1 to 197.173.255.254197.173.255.255131,070
216197.174.0.0/15197.174.0.1 to 197.175.255.254197.175.255.255131,070
217197.176.0.0/15197.176.0.1 to 197.177.255.254197.177.255.255131,070
218197.178.0.0/15197.178.0.1 to 197.179.255.254197.179.255.255131,070
219197.180.0.0/15197.180.0.1 to 197.181.255.254197.181.255.255131,070
220197.182.0.0/15197.182.0.1 to 197.183.255.254197.183.255.255131,070
221197.184.0.0/15197.184.0.1 to 197.185.255.254197.185.255.255131,070
222197.186.0.0/15197.186.0.1 to 197.187.255.254197.187.255.255131,070
223197.188.0.0/15197.188.0.1 to 197.189.255.254197.189.255.255131,070
224197.190.0.0/15197.190.0.1 to 197.191.255.254197.191.255.255131,070
225197.192.0.0/15197.192.0.1 to 197.193.255.254197.193.255.255131,070
226197.194.0.0/15197.194.0.1 to 197.195.255.254197.195.255.255131,070
227197.196.0.0/15197.196.0.1 to 197.197.255.254197.197.255.255131,070
228197.198.0.0/15197.198.0.1 to 197.199.255.254197.199.255.255131,070
229197.200.0.0/15197.200.0.1 to 197.201.255.254197.201.255.255131,070
230197.202.0.0/15197.202.0.1 to 197.203.255.254197.203.255.255131,070
231197.204.0.0/15197.204.0.1 to 197.205.255.254197.205.255.255131,070
232197.206.0.0/15197.206.0.1 to 197.207.255.254197.207.255.255131,070
233197.208.0.0/15197.208.0.1 to 197.209.255.254197.209.255.255131,070
234197.210.0.0/15197.210.0.1 to 197.211.255.254197.211.255.255131,070
235197.212.0.0/15197.212.0.1 to 197.213.255.254197.213.255.255131,070
236197.214.0.0/15197.214.0.1 to 197.215.255.254197.215.255.255131,070
237197.216.0.0/15197.216.0.1 to 197.217.255.254197.217.255.255131,070
238197.218.0.0/15197.218.0.1 to 197.219.255.254197.219.255.255131,070
239197.220.0.0/15197.220.0.1 to 197.221.255.254197.221.255.255131,070
240197.222.0.0/15197.222.0.1 to 197.223.255.254197.223.255.255131,070
241197.224.0.0/15197.224.0.1 to 197.225.255.254197.225.255.255131,070
242197.226.0.0/15197.226.0.1 to 197.227.255.254197.227.255.255131,070
243197.228.0.0/15197.228.0.1 to 197.229.255.254197.229.255.255131,070
244197.230.0.0/15197.230.0.1 to 197.231.255.254197.231.255.255131,070
245197.232.0.0/15197.232.0.1 to 197.233.255.254197.233.255.255131,070
246197.234.0.0/15197.234.0.1 to 197.235.255.254197.235.255.255131,070
247197.236.0.0/15197.236.0.1 to 197.237.255.254197.237.255.255131,070
248197.238.0.0/15197.238.0.1 to 197.239.255.254197.239.255.255131,070
249197.240.0.0/15197.240.0.1 to 197.241.255.254197.241.255.255131,070
250197.242.0.0/15197.242.0.1 to 197.243.255.254197.243.255.255131,070
251197.244.0.0/15197.244.0.1 to 197.245.255.254197.245.255.255131,070
252197.246.0.0/15197.246.0.1 to 197.247.255.254197.247.255.255131,070
253197.248.0.0/15197.248.0.1 to 197.249.255.254197.249.255.255131,070
254197.250.0.0/15197.250.0.1 to 197.251.255.254197.251.255.255131,070
255197.252.0.0/15197.252.0.1 to 197.253.255.254197.253.255.255131,070
256197.254.0.0/15197.254.0.1 to 197.255.255.254197.255.255.255131,070

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