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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.

Network174.0.0.0/7
Usable hosts33,554,430
Subnet mask254.0.0.0
Addresses33,554,432
Network address
174.0.0.0
Broadcast address
175.255.255.255
First usable
174.0.0.1
Last usable
175.255.255.254
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
B (default /16)
As numbers
Hex AE000000 · Integer 2919235584 to 2952790015
Reverse DNS zones
174.in-addr.arpa
175.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
Address10101110.00000000.00000000.00000000174.0.0.0
Subnet mask11111110.00000000.00000000.00000000254.0.0.0
Network10101110.00000000.00000000.00000000174.0.0.0
Broadcast10101111.11111111.11111111.11111111175.255.255.255
Split into smaller subnets/15
/8 (2)/9 (4)/10 (8)/11 (16)/12 (32)/13 (64)/14 (128)/15 (256)/16 (512)/17 (1,024)/18 (2,048)/19 (4,096)

174.0.0.0/7 makes 256 subnets of /15.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
1174.0.0.0/15174.0.0.1 to 174.1.255.254174.1.255.255131,070
2174.2.0.0/15174.2.0.1 to 174.3.255.254174.3.255.255131,070
3174.4.0.0/15174.4.0.1 to 174.5.255.254174.5.255.255131,070
4174.6.0.0/15174.6.0.1 to 174.7.255.254174.7.255.255131,070
5174.8.0.0/15174.8.0.1 to 174.9.255.254174.9.255.255131,070
6174.10.0.0/15174.10.0.1 to 174.11.255.254174.11.255.255131,070
7174.12.0.0/15174.12.0.1 to 174.13.255.254174.13.255.255131,070
8174.14.0.0/15174.14.0.1 to 174.15.255.254174.15.255.255131,070
9174.16.0.0/15174.16.0.1 to 174.17.255.254174.17.255.255131,070
10174.18.0.0/15174.18.0.1 to 174.19.255.254174.19.255.255131,070
11174.20.0.0/15174.20.0.1 to 174.21.255.254174.21.255.255131,070
12174.22.0.0/15174.22.0.1 to 174.23.255.254174.23.255.255131,070
13174.24.0.0/15174.24.0.1 to 174.25.255.254174.25.255.255131,070
14174.26.0.0/15174.26.0.1 to 174.27.255.254174.27.255.255131,070
15174.28.0.0/15174.28.0.1 to 174.29.255.254174.29.255.255131,070
16174.30.0.0/15174.30.0.1 to 174.31.255.254174.31.255.255131,070
17174.32.0.0/15174.32.0.1 to 174.33.255.254174.33.255.255131,070
18174.34.0.0/15174.34.0.1 to 174.35.255.254174.35.255.255131,070
19174.36.0.0/15174.36.0.1 to 174.37.255.254174.37.255.255131,070
20174.38.0.0/15174.38.0.1 to 174.39.255.254174.39.255.255131,070
21174.40.0.0/15174.40.0.1 to 174.41.255.254174.41.255.255131,070
22174.42.0.0/15174.42.0.1 to 174.43.255.254174.43.255.255131,070
23174.44.0.0/15174.44.0.1 to 174.45.255.254174.45.255.255131,070
24174.46.0.0/15174.46.0.1 to 174.47.255.254174.47.255.255131,070
25174.48.0.0/15174.48.0.1 to 174.49.255.254174.49.255.255131,070
26174.50.0.0/15174.50.0.1 to 174.51.255.254174.51.255.255131,070
27174.52.0.0/15174.52.0.1 to 174.53.255.254174.53.255.255131,070
28174.54.0.0/15174.54.0.1 to 174.55.255.254174.55.255.255131,070
29174.56.0.0/15174.56.0.1 to 174.57.255.254174.57.255.255131,070
30174.58.0.0/15174.58.0.1 to 174.59.255.254174.59.255.255131,070
31174.60.0.0/15174.60.0.1 to 174.61.255.254174.61.255.255131,070
32174.62.0.0/15174.62.0.1 to 174.63.255.254174.63.255.255131,070
33174.64.0.0/15174.64.0.1 to 174.65.255.254174.65.255.255131,070
34174.66.0.0/15174.66.0.1 to 174.67.255.254174.67.255.255131,070
35174.68.0.0/15174.68.0.1 to 174.69.255.254174.69.255.255131,070
36174.70.0.0/15174.70.0.1 to 174.71.255.254174.71.255.255131,070
37174.72.0.0/15174.72.0.1 to 174.73.255.254174.73.255.255131,070
38174.74.0.0/15174.74.0.1 to 174.75.255.254174.75.255.255131,070
39174.76.0.0/15174.76.0.1 to 174.77.255.254174.77.255.255131,070
40174.78.0.0/15174.78.0.1 to 174.79.255.254174.79.255.255131,070
41174.80.0.0/15174.80.0.1 to 174.81.255.254174.81.255.255131,070
42174.82.0.0/15174.82.0.1 to 174.83.255.254174.83.255.255131,070
43174.84.0.0/15174.84.0.1 to 174.85.255.254174.85.255.255131,070
44174.86.0.0/15174.86.0.1 to 174.87.255.254174.87.255.255131,070
45174.88.0.0/15174.88.0.1 to 174.89.255.254174.89.255.255131,070
46174.90.0.0/15174.90.0.1 to 174.91.255.254174.91.255.255131,070
47174.92.0.0/15174.92.0.1 to 174.93.255.254174.93.255.255131,070
48174.94.0.0/15174.94.0.1 to 174.95.255.254174.95.255.255131,070
49174.96.0.0/15174.96.0.1 to 174.97.255.254174.97.255.255131,070
50174.98.0.0/15174.98.0.1 to 174.99.255.254174.99.255.255131,070
51174.100.0.0/15174.100.0.1 to 174.101.255.254174.101.255.255131,070
52174.102.0.0/15174.102.0.1 to 174.103.255.254174.103.255.255131,070
53174.104.0.0/15174.104.0.1 to 174.105.255.254174.105.255.255131,070
54174.106.0.0/15174.106.0.1 to 174.107.255.254174.107.255.255131,070
55174.108.0.0/15174.108.0.1 to 174.109.255.254174.109.255.255131,070
56174.110.0.0/15174.110.0.1 to 174.111.255.254174.111.255.255131,070
57174.112.0.0/15174.112.0.1 to 174.113.255.254174.113.255.255131,070
58174.114.0.0/15174.114.0.1 to 174.115.255.254174.115.255.255131,070
59174.116.0.0/15174.116.0.1 to 174.117.255.254174.117.255.255131,070
60174.118.0.0/15174.118.0.1 to 174.119.255.254174.119.255.255131,070
61174.120.0.0/15174.120.0.1 to 174.121.255.254174.121.255.255131,070
62174.122.0.0/15174.122.0.1 to 174.123.255.254174.123.255.255131,070
63174.124.0.0/15174.124.0.1 to 174.125.255.254174.125.255.255131,070
64174.126.0.0/15174.126.0.1 to 174.127.255.254174.127.255.255131,070
65174.128.0.0/15174.128.0.1 to 174.129.255.254174.129.255.255131,070
66174.130.0.0/15174.130.0.1 to 174.131.255.254174.131.255.255131,070
67174.132.0.0/15174.132.0.1 to 174.133.255.254174.133.255.255131,070
68174.134.0.0/15174.134.0.1 to 174.135.255.254174.135.255.255131,070
69174.136.0.0/15174.136.0.1 to 174.137.255.254174.137.255.255131,070
70174.138.0.0/15174.138.0.1 to 174.139.255.254174.139.255.255131,070
71174.140.0.0/15174.140.0.1 to 174.141.255.254174.141.255.255131,070
72174.142.0.0/15174.142.0.1 to 174.143.255.254174.143.255.255131,070
73174.144.0.0/15174.144.0.1 to 174.145.255.254174.145.255.255131,070
74174.146.0.0/15174.146.0.1 to 174.147.255.254174.147.255.255131,070
75174.148.0.0/15174.148.0.1 to 174.149.255.254174.149.255.255131,070
76174.150.0.0/15174.150.0.1 to 174.151.255.254174.151.255.255131,070
77174.152.0.0/15174.152.0.1 to 174.153.255.254174.153.255.255131,070
78174.154.0.0/15174.154.0.1 to 174.155.255.254174.155.255.255131,070
79174.156.0.0/15174.156.0.1 to 174.157.255.254174.157.255.255131,070
80174.158.0.0/15174.158.0.1 to 174.159.255.254174.159.255.255131,070
81174.160.0.0/15174.160.0.1 to 174.161.255.254174.161.255.255131,070
82174.162.0.0/15174.162.0.1 to 174.163.255.254174.163.255.255131,070
83174.164.0.0/15174.164.0.1 to 174.165.255.254174.165.255.255131,070
84174.166.0.0/15174.166.0.1 to 174.167.255.254174.167.255.255131,070
85174.168.0.0/15174.168.0.1 to 174.169.255.254174.169.255.255131,070
86174.170.0.0/15174.170.0.1 to 174.171.255.254174.171.255.255131,070
87174.172.0.0/15174.172.0.1 to 174.173.255.254174.173.255.255131,070
88174.174.0.0/15174.174.0.1 to 174.175.255.254174.175.255.255131,070
89174.176.0.0/15174.176.0.1 to 174.177.255.254174.177.255.255131,070
90174.178.0.0/15174.178.0.1 to 174.179.255.254174.179.255.255131,070
91174.180.0.0/15174.180.0.1 to 174.181.255.254174.181.255.255131,070
92174.182.0.0/15174.182.0.1 to 174.183.255.254174.183.255.255131,070
93174.184.0.0/15174.184.0.1 to 174.185.255.254174.185.255.255131,070
94174.186.0.0/15174.186.0.1 to 174.187.255.254174.187.255.255131,070
95174.188.0.0/15174.188.0.1 to 174.189.255.254174.189.255.255131,070
96174.190.0.0/15174.190.0.1 to 174.191.255.254174.191.255.255131,070
97174.192.0.0/15174.192.0.1 to 174.193.255.254174.193.255.255131,070
98174.194.0.0/15174.194.0.1 to 174.195.255.254174.195.255.255131,070
99174.196.0.0/15174.196.0.1 to 174.197.255.254174.197.255.255131,070
100174.198.0.0/15174.198.0.1 to 174.199.255.254174.199.255.255131,070
101174.200.0.0/15174.200.0.1 to 174.201.255.254174.201.255.255131,070
102174.202.0.0/15174.202.0.1 to 174.203.255.254174.203.255.255131,070
103174.204.0.0/15174.204.0.1 to 174.205.255.254174.205.255.255131,070
104174.206.0.0/15174.206.0.1 to 174.207.255.254174.207.255.255131,070
105174.208.0.0/15174.208.0.1 to 174.209.255.254174.209.255.255131,070
106174.210.0.0/15174.210.0.1 to 174.211.255.254174.211.255.255131,070
107174.212.0.0/15174.212.0.1 to 174.213.255.254174.213.255.255131,070
108174.214.0.0/15174.214.0.1 to 174.215.255.254174.215.255.255131,070
109174.216.0.0/15174.216.0.1 to 174.217.255.254174.217.255.255131,070
110174.218.0.0/15174.218.0.1 to 174.219.255.254174.219.255.255131,070
111174.220.0.0/15174.220.0.1 to 174.221.255.254174.221.255.255131,070
112174.222.0.0/15174.222.0.1 to 174.223.255.254174.223.255.255131,070
113174.224.0.0/15174.224.0.1 to 174.225.255.254174.225.255.255131,070
114174.226.0.0/15174.226.0.1 to 174.227.255.254174.227.255.255131,070
115174.228.0.0/15174.228.0.1 to 174.229.255.254174.229.255.255131,070
116174.230.0.0/15174.230.0.1 to 174.231.255.254174.231.255.255131,070
117174.232.0.0/15174.232.0.1 to 174.233.255.254174.233.255.255131,070
118174.234.0.0/15174.234.0.1 to 174.235.255.254174.235.255.255131,070
119174.236.0.0/15174.236.0.1 to 174.237.255.254174.237.255.255131,070
120174.238.0.0/15174.238.0.1 to 174.239.255.254174.239.255.255131,070
121174.240.0.0/15174.240.0.1 to 174.241.255.254174.241.255.255131,070
122174.242.0.0/15174.242.0.1 to 174.243.255.254174.243.255.255131,070
123174.244.0.0/15174.244.0.1 to 174.245.255.254174.245.255.255131,070
124174.246.0.0/15174.246.0.1 to 174.247.255.254174.247.255.255131,070
125174.248.0.0/15174.248.0.1 to 174.249.255.254174.249.255.255131,070
126174.250.0.0/15174.250.0.1 to 174.251.255.254174.251.255.255131,070
127174.252.0.0/15174.252.0.1 to 174.253.255.254174.253.255.255131,070
128174.254.0.0/15174.254.0.1 to 174.255.255.254174.255.255.255131,070
129175.0.0.0/15175.0.0.1 to 175.1.255.254175.1.255.255131,070
130175.2.0.0/15175.2.0.1 to 175.3.255.254175.3.255.255131,070
131175.4.0.0/15175.4.0.1 to 175.5.255.254175.5.255.255131,070
132175.6.0.0/15175.6.0.1 to 175.7.255.254175.7.255.255131,070
133175.8.0.0/15175.8.0.1 to 175.9.255.254175.9.255.255131,070
134175.10.0.0/15175.10.0.1 to 175.11.255.254175.11.255.255131,070
135175.12.0.0/15175.12.0.1 to 175.13.255.254175.13.255.255131,070
136175.14.0.0/15175.14.0.1 to 175.15.255.254175.15.255.255131,070
137175.16.0.0/15175.16.0.1 to 175.17.255.254175.17.255.255131,070
138175.18.0.0/15175.18.0.1 to 175.19.255.254175.19.255.255131,070
139175.20.0.0/15175.20.0.1 to 175.21.255.254175.21.255.255131,070
140175.22.0.0/15175.22.0.1 to 175.23.255.254175.23.255.255131,070
141175.24.0.0/15175.24.0.1 to 175.25.255.254175.25.255.255131,070
142175.26.0.0/15175.26.0.1 to 175.27.255.254175.27.255.255131,070
143175.28.0.0/15175.28.0.1 to 175.29.255.254175.29.255.255131,070
144175.30.0.0/15175.30.0.1 to 175.31.255.254175.31.255.255131,070
145175.32.0.0/15175.32.0.1 to 175.33.255.254175.33.255.255131,070
146175.34.0.0/15175.34.0.1 to 175.35.255.254175.35.255.255131,070
147175.36.0.0/15175.36.0.1 to 175.37.255.254175.37.255.255131,070
148175.38.0.0/15175.38.0.1 to 175.39.255.254175.39.255.255131,070
149175.40.0.0/15175.40.0.1 to 175.41.255.254175.41.255.255131,070
150175.42.0.0/15175.42.0.1 to 175.43.255.254175.43.255.255131,070
151175.44.0.0/15175.44.0.1 to 175.45.255.254175.45.255.255131,070
152175.46.0.0/15175.46.0.1 to 175.47.255.254175.47.255.255131,070
153175.48.0.0/15175.48.0.1 to 175.49.255.254175.49.255.255131,070
154175.50.0.0/15175.50.0.1 to 175.51.255.254175.51.255.255131,070
155175.52.0.0/15175.52.0.1 to 175.53.255.254175.53.255.255131,070
156175.54.0.0/15175.54.0.1 to 175.55.255.254175.55.255.255131,070
157175.56.0.0/15175.56.0.1 to 175.57.255.254175.57.255.255131,070
158175.58.0.0/15175.58.0.1 to 175.59.255.254175.59.255.255131,070
159175.60.0.0/15175.60.0.1 to 175.61.255.254175.61.255.255131,070
160175.62.0.0/15175.62.0.1 to 175.63.255.254175.63.255.255131,070
161175.64.0.0/15175.64.0.1 to 175.65.255.254175.65.255.255131,070
162175.66.0.0/15175.66.0.1 to 175.67.255.254175.67.255.255131,070
163175.68.0.0/15175.68.0.1 to 175.69.255.254175.69.255.255131,070
164175.70.0.0/15175.70.0.1 to 175.71.255.254175.71.255.255131,070
165175.72.0.0/15175.72.0.1 to 175.73.255.254175.73.255.255131,070
166175.74.0.0/15175.74.0.1 to 175.75.255.254175.75.255.255131,070
167175.76.0.0/15175.76.0.1 to 175.77.255.254175.77.255.255131,070
168175.78.0.0/15175.78.0.1 to 175.79.255.254175.79.255.255131,070
169175.80.0.0/15175.80.0.1 to 175.81.255.254175.81.255.255131,070
170175.82.0.0/15175.82.0.1 to 175.83.255.254175.83.255.255131,070
171175.84.0.0/15175.84.0.1 to 175.85.255.254175.85.255.255131,070
172175.86.0.0/15175.86.0.1 to 175.87.255.254175.87.255.255131,070
173175.88.0.0/15175.88.0.1 to 175.89.255.254175.89.255.255131,070
174175.90.0.0/15175.90.0.1 to 175.91.255.254175.91.255.255131,070
175175.92.0.0/15175.92.0.1 to 175.93.255.254175.93.255.255131,070
176175.94.0.0/15175.94.0.1 to 175.95.255.254175.95.255.255131,070
177175.96.0.0/15175.96.0.1 to 175.97.255.254175.97.255.255131,070
178175.98.0.0/15175.98.0.1 to 175.99.255.254175.99.255.255131,070
179175.100.0.0/15175.100.0.1 to 175.101.255.254175.101.255.255131,070
180175.102.0.0/15175.102.0.1 to 175.103.255.254175.103.255.255131,070
181175.104.0.0/15175.104.0.1 to 175.105.255.254175.105.255.255131,070
182175.106.0.0/15175.106.0.1 to 175.107.255.254175.107.255.255131,070
183175.108.0.0/15175.108.0.1 to 175.109.255.254175.109.255.255131,070
184175.110.0.0/15175.110.0.1 to 175.111.255.254175.111.255.255131,070
185175.112.0.0/15175.112.0.1 to 175.113.255.254175.113.255.255131,070
186175.114.0.0/15175.114.0.1 to 175.115.255.254175.115.255.255131,070
187175.116.0.0/15175.116.0.1 to 175.117.255.254175.117.255.255131,070
188175.118.0.0/15175.118.0.1 to 175.119.255.254175.119.255.255131,070
189175.120.0.0/15175.120.0.1 to 175.121.255.254175.121.255.255131,070
190175.122.0.0/15175.122.0.1 to 175.123.255.254175.123.255.255131,070
191175.124.0.0/15175.124.0.1 to 175.125.255.254175.125.255.255131,070
192175.126.0.0/15175.126.0.1 to 175.127.255.254175.127.255.255131,070
193175.128.0.0/15175.128.0.1 to 175.129.255.254175.129.255.255131,070
194175.130.0.0/15175.130.0.1 to 175.131.255.254175.131.255.255131,070
195175.132.0.0/15175.132.0.1 to 175.133.255.254175.133.255.255131,070
196175.134.0.0/15175.134.0.1 to 175.135.255.254175.135.255.255131,070
197175.136.0.0/15175.136.0.1 to 175.137.255.254175.137.255.255131,070
198175.138.0.0/15175.138.0.1 to 175.139.255.254175.139.255.255131,070
199175.140.0.0/15175.140.0.1 to 175.141.255.254175.141.255.255131,070
200175.142.0.0/15175.142.0.1 to 175.143.255.254175.143.255.255131,070
201175.144.0.0/15175.144.0.1 to 175.145.255.254175.145.255.255131,070
202175.146.0.0/15175.146.0.1 to 175.147.255.254175.147.255.255131,070
203175.148.0.0/15175.148.0.1 to 175.149.255.254175.149.255.255131,070
204175.150.0.0/15175.150.0.1 to 175.151.255.254175.151.255.255131,070
205175.152.0.0/15175.152.0.1 to 175.153.255.254175.153.255.255131,070
206175.154.0.0/15175.154.0.1 to 175.155.255.254175.155.255.255131,070
207175.156.0.0/15175.156.0.1 to 175.157.255.254175.157.255.255131,070
208175.158.0.0/15175.158.0.1 to 175.159.255.254175.159.255.255131,070
209175.160.0.0/15175.160.0.1 to 175.161.255.254175.161.255.255131,070
210175.162.0.0/15175.162.0.1 to 175.163.255.254175.163.255.255131,070
211175.164.0.0/15175.164.0.1 to 175.165.255.254175.165.255.255131,070
212175.166.0.0/15175.166.0.1 to 175.167.255.254175.167.255.255131,070
213175.168.0.0/15175.168.0.1 to 175.169.255.254175.169.255.255131,070
214175.170.0.0/15175.170.0.1 to 175.171.255.254175.171.255.255131,070
215175.172.0.0/15175.172.0.1 to 175.173.255.254175.173.255.255131,070
216175.174.0.0/15175.174.0.1 to 175.175.255.254175.175.255.255131,070
217175.176.0.0/15175.176.0.1 to 175.177.255.254175.177.255.255131,070
218175.178.0.0/15175.178.0.1 to 175.179.255.254175.179.255.255131,070
219175.180.0.0/15175.180.0.1 to 175.181.255.254175.181.255.255131,070
220175.182.0.0/15175.182.0.1 to 175.183.255.254175.183.255.255131,070
221175.184.0.0/15175.184.0.1 to 175.185.255.254175.185.255.255131,070
222175.186.0.0/15175.186.0.1 to 175.187.255.254175.187.255.255131,070
223175.188.0.0/15175.188.0.1 to 175.189.255.254175.189.255.255131,070
224175.190.0.0/15175.190.0.1 to 175.191.255.254175.191.255.255131,070
225175.192.0.0/15175.192.0.1 to 175.193.255.254175.193.255.255131,070
226175.194.0.0/15175.194.0.1 to 175.195.255.254175.195.255.255131,070
227175.196.0.0/15175.196.0.1 to 175.197.255.254175.197.255.255131,070
228175.198.0.0/15175.198.0.1 to 175.199.255.254175.199.255.255131,070
229175.200.0.0/15175.200.0.1 to 175.201.255.254175.201.255.255131,070
230175.202.0.0/15175.202.0.1 to 175.203.255.254175.203.255.255131,070
231175.204.0.0/15175.204.0.1 to 175.205.255.254175.205.255.255131,070
232175.206.0.0/15175.206.0.1 to 175.207.255.254175.207.255.255131,070
233175.208.0.0/15175.208.0.1 to 175.209.255.254175.209.255.255131,070
234175.210.0.0/15175.210.0.1 to 175.211.255.254175.211.255.255131,070
235175.212.0.0/15175.212.0.1 to 175.213.255.254175.213.255.255131,070
236175.214.0.0/15175.214.0.1 to 175.215.255.254175.215.255.255131,070
237175.216.0.0/15175.216.0.1 to 175.217.255.254175.217.255.255131,070
238175.218.0.0/15175.218.0.1 to 175.219.255.254175.219.255.255131,070
239175.220.0.0/15175.220.0.1 to 175.221.255.254175.221.255.255131,070
240175.222.0.0/15175.222.0.1 to 175.223.255.254175.223.255.255131,070
241175.224.0.0/15175.224.0.1 to 175.225.255.254175.225.255.255131,070
242175.226.0.0/15175.226.0.1 to 175.227.255.254175.227.255.255131,070
243175.228.0.0/15175.228.0.1 to 175.229.255.254175.229.255.255131,070
244175.230.0.0/15175.230.0.1 to 175.231.255.254175.231.255.255131,070
245175.232.0.0/15175.232.0.1 to 175.233.255.254175.233.255.255131,070
246175.234.0.0/15175.234.0.1 to 175.235.255.254175.235.255.255131,070
247175.236.0.0/15175.236.0.1 to 175.237.255.254175.237.255.255131,070
248175.238.0.0/15175.238.0.1 to 175.239.255.254175.239.255.255131,070
249175.240.0.0/15175.240.0.1 to 175.241.255.254175.241.255.255131,070
250175.242.0.0/15175.242.0.1 to 175.243.255.254175.243.255.255131,070
251175.244.0.0/15175.244.0.1 to 175.245.255.254175.245.255.255131,070
252175.246.0.0/15175.246.0.1 to 175.247.255.254175.247.255.255131,070
253175.248.0.0/15175.248.0.1 to 175.249.255.254175.249.255.255131,070
254175.250.0.0/15175.250.0.1 to 175.251.255.254175.251.255.255131,070
255175.252.0.0/15175.252.0.1 to 175.253.255.254175.253.255.255131,070
256175.254.0.0/15175.254.0.1 to 175.255.255.254175.255.255.255131,070

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

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.