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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.

Network158.252.0.0/14
Usable hosts262,142
Subnet mask255.252.0.0
Addresses262,144
Network address
158.252.0.0
Broadcast address
158.255.255.255
First usable
158.252.0.1
Last usable
158.255.255.254
Usable hosts
262,142 (262,144 less the network and broadcast addresses)
Subnet mask
255.252.0.0
Wildcard mask
0.3.255.255 (Cisco ACLs, OSPF)
Prefix length
/14
Type
Public public
Old class
B (default /16)
As numbers
Hex 9EFC0000 · Integer 2667315200 to 2667577343
Reverse DNS zones
252.158.in-addr.arpa
253.158.in-addr.arpa
254.158.in-addr.arpa
255.158.in-addr.arpa
/14 is not on a 8-bit boundary, so it takes 4 /16 zones.
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address10011110.11111100.00000000.00000000158.252.0.0
Subnet mask11111111.11111100.00000000.00000000255.252.0.0
Network10011110.11111100.00000000.00000000158.252.0.0
Broadcast10011110.11111111.11111111.11111111158.255.255.255
Split into smaller subnets/24
/15 (2)/16 (4)/17 (8)/18 (16)/19 (32)/20 (64)/21 (128)/22 (256)/23 (512)/24 (1,024)/25 (2,048)/26 (4,096)

158.252.0.0/14 makes 1,024 subnets of /24; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
1158.252.0.0/24158.252.0.1 to 158.252.0.254158.252.0.255254
2158.252.1.0/24158.252.1.1 to 158.252.1.254158.252.1.255254
3158.252.2.0/24158.252.2.1 to 158.252.2.254158.252.2.255254
4158.252.3.0/24158.252.3.1 to 158.252.3.254158.252.3.255254
5158.252.4.0/24158.252.4.1 to 158.252.4.254158.252.4.255254
6158.252.5.0/24158.252.5.1 to 158.252.5.254158.252.5.255254
7158.252.6.0/24158.252.6.1 to 158.252.6.254158.252.6.255254
8158.252.7.0/24158.252.7.1 to 158.252.7.254158.252.7.255254
9158.252.8.0/24158.252.8.1 to 158.252.8.254158.252.8.255254
10158.252.9.0/24158.252.9.1 to 158.252.9.254158.252.9.255254
11158.252.10.0/24158.252.10.1 to 158.252.10.254158.252.10.255254
12158.252.11.0/24158.252.11.1 to 158.252.11.254158.252.11.255254
13158.252.12.0/24158.252.12.1 to 158.252.12.254158.252.12.255254
14158.252.13.0/24158.252.13.1 to 158.252.13.254158.252.13.255254
15158.252.14.0/24158.252.14.1 to 158.252.14.254158.252.14.255254
16158.252.15.0/24158.252.15.1 to 158.252.15.254158.252.15.255254
17158.252.16.0/24158.252.16.1 to 158.252.16.254158.252.16.255254
18158.252.17.0/24158.252.17.1 to 158.252.17.254158.252.17.255254
19158.252.18.0/24158.252.18.1 to 158.252.18.254158.252.18.255254
20158.252.19.0/24158.252.19.1 to 158.252.19.254158.252.19.255254
21158.252.20.0/24158.252.20.1 to 158.252.20.254158.252.20.255254
22158.252.21.0/24158.252.21.1 to 158.252.21.254158.252.21.255254
23158.252.22.0/24158.252.22.1 to 158.252.22.254158.252.22.255254
24158.252.23.0/24158.252.23.1 to 158.252.23.254158.252.23.255254
25158.252.24.0/24158.252.24.1 to 158.252.24.254158.252.24.255254
26158.252.25.0/24158.252.25.1 to 158.252.25.254158.252.25.255254
27158.252.26.0/24158.252.26.1 to 158.252.26.254158.252.26.255254
28158.252.27.0/24158.252.27.1 to 158.252.27.254158.252.27.255254
29158.252.28.0/24158.252.28.1 to 158.252.28.254158.252.28.255254
30158.252.29.0/24158.252.29.1 to 158.252.29.254158.252.29.255254
31158.252.30.0/24158.252.30.1 to 158.252.30.254158.252.30.255254
32158.252.31.0/24158.252.31.1 to 158.252.31.254158.252.31.255254
33158.252.32.0/24158.252.32.1 to 158.252.32.254158.252.32.255254
34158.252.33.0/24158.252.33.1 to 158.252.33.254158.252.33.255254
35158.252.34.0/24158.252.34.1 to 158.252.34.254158.252.34.255254
36158.252.35.0/24158.252.35.1 to 158.252.35.254158.252.35.255254
37158.252.36.0/24158.252.36.1 to 158.252.36.254158.252.36.255254
38158.252.37.0/24158.252.37.1 to 158.252.37.254158.252.37.255254
39158.252.38.0/24158.252.38.1 to 158.252.38.254158.252.38.255254
40158.252.39.0/24158.252.39.1 to 158.252.39.254158.252.39.255254
41158.252.40.0/24158.252.40.1 to 158.252.40.254158.252.40.255254
42158.252.41.0/24158.252.41.1 to 158.252.41.254158.252.41.255254
43158.252.42.0/24158.252.42.1 to 158.252.42.254158.252.42.255254
44158.252.43.0/24158.252.43.1 to 158.252.43.254158.252.43.255254
45158.252.44.0/24158.252.44.1 to 158.252.44.254158.252.44.255254
46158.252.45.0/24158.252.45.1 to 158.252.45.254158.252.45.255254
47158.252.46.0/24158.252.46.1 to 158.252.46.254158.252.46.255254
48158.252.47.0/24158.252.47.1 to 158.252.47.254158.252.47.255254
49158.252.48.0/24158.252.48.1 to 158.252.48.254158.252.48.255254
50158.252.49.0/24158.252.49.1 to 158.252.49.254158.252.49.255254
51158.252.50.0/24158.252.50.1 to 158.252.50.254158.252.50.255254
52158.252.51.0/24158.252.51.1 to 158.252.51.254158.252.51.255254
53158.252.52.0/24158.252.52.1 to 158.252.52.254158.252.52.255254
54158.252.53.0/24158.252.53.1 to 158.252.53.254158.252.53.255254
55158.252.54.0/24158.252.54.1 to 158.252.54.254158.252.54.255254
56158.252.55.0/24158.252.55.1 to 158.252.55.254158.252.55.255254
57158.252.56.0/24158.252.56.1 to 158.252.56.254158.252.56.255254
58158.252.57.0/24158.252.57.1 to 158.252.57.254158.252.57.255254
59158.252.58.0/24158.252.58.1 to 158.252.58.254158.252.58.255254
60158.252.59.0/24158.252.59.1 to 158.252.59.254158.252.59.255254
61158.252.60.0/24158.252.60.1 to 158.252.60.254158.252.60.255254
62158.252.61.0/24158.252.61.1 to 158.252.61.254158.252.61.255254
63158.252.62.0/24158.252.62.1 to 158.252.62.254158.252.62.255254
64158.252.63.0/24158.252.63.1 to 158.252.63.254158.252.63.255254
65158.252.64.0/24158.252.64.1 to 158.252.64.254158.252.64.255254
66158.252.65.0/24158.252.65.1 to 158.252.65.254158.252.65.255254
67158.252.66.0/24158.252.66.1 to 158.252.66.254158.252.66.255254
68158.252.67.0/24158.252.67.1 to 158.252.67.254158.252.67.255254
69158.252.68.0/24158.252.68.1 to 158.252.68.254158.252.68.255254
70158.252.69.0/24158.252.69.1 to 158.252.69.254158.252.69.255254
71158.252.70.0/24158.252.70.1 to 158.252.70.254158.252.70.255254
72158.252.71.0/24158.252.71.1 to 158.252.71.254158.252.71.255254
73158.252.72.0/24158.252.72.1 to 158.252.72.254158.252.72.255254
74158.252.73.0/24158.252.73.1 to 158.252.73.254158.252.73.255254
75158.252.74.0/24158.252.74.1 to 158.252.74.254158.252.74.255254
76158.252.75.0/24158.252.75.1 to 158.252.75.254158.252.75.255254
77158.252.76.0/24158.252.76.1 to 158.252.76.254158.252.76.255254
78158.252.77.0/24158.252.77.1 to 158.252.77.254158.252.77.255254
79158.252.78.0/24158.252.78.1 to 158.252.78.254158.252.78.255254
80158.252.79.0/24158.252.79.1 to 158.252.79.254158.252.79.255254
81158.252.80.0/24158.252.80.1 to 158.252.80.254158.252.80.255254
82158.252.81.0/24158.252.81.1 to 158.252.81.254158.252.81.255254
83158.252.82.0/24158.252.82.1 to 158.252.82.254158.252.82.255254
84158.252.83.0/24158.252.83.1 to 158.252.83.254158.252.83.255254
85158.252.84.0/24158.252.84.1 to 158.252.84.254158.252.84.255254
86158.252.85.0/24158.252.85.1 to 158.252.85.254158.252.85.255254
87158.252.86.0/24158.252.86.1 to 158.252.86.254158.252.86.255254
88158.252.87.0/24158.252.87.1 to 158.252.87.254158.252.87.255254
89158.252.88.0/24158.252.88.1 to 158.252.88.254158.252.88.255254
90158.252.89.0/24158.252.89.1 to 158.252.89.254158.252.89.255254
91158.252.90.0/24158.252.90.1 to 158.252.90.254158.252.90.255254
92158.252.91.0/24158.252.91.1 to 158.252.91.254158.252.91.255254
93158.252.92.0/24158.252.92.1 to 158.252.92.254158.252.92.255254
94158.252.93.0/24158.252.93.1 to 158.252.93.254158.252.93.255254
95158.252.94.0/24158.252.94.1 to 158.252.94.254158.252.94.255254
96158.252.95.0/24158.252.95.1 to 158.252.95.254158.252.95.255254
97158.252.96.0/24158.252.96.1 to 158.252.96.254158.252.96.255254
98158.252.97.0/24158.252.97.1 to 158.252.97.254158.252.97.255254
99158.252.98.0/24158.252.98.1 to 158.252.98.254158.252.98.255254
100158.252.99.0/24158.252.99.1 to 158.252.99.254158.252.99.255254
101158.252.100.0/24158.252.100.1 to 158.252.100.254158.252.100.255254
102158.252.101.0/24158.252.101.1 to 158.252.101.254158.252.101.255254
103158.252.102.0/24158.252.102.1 to 158.252.102.254158.252.102.255254
104158.252.103.0/24158.252.103.1 to 158.252.103.254158.252.103.255254
105158.252.104.0/24158.252.104.1 to 158.252.104.254158.252.104.255254
106158.252.105.0/24158.252.105.1 to 158.252.105.254158.252.105.255254
107158.252.106.0/24158.252.106.1 to 158.252.106.254158.252.106.255254
108158.252.107.0/24158.252.107.1 to 158.252.107.254158.252.107.255254
109158.252.108.0/24158.252.108.1 to 158.252.108.254158.252.108.255254
110158.252.109.0/24158.252.109.1 to 158.252.109.254158.252.109.255254
111158.252.110.0/24158.252.110.1 to 158.252.110.254158.252.110.255254
112158.252.111.0/24158.252.111.1 to 158.252.111.254158.252.111.255254
113158.252.112.0/24158.252.112.1 to 158.252.112.254158.252.112.255254
114158.252.113.0/24158.252.113.1 to 158.252.113.254158.252.113.255254
115158.252.114.0/24158.252.114.1 to 158.252.114.254158.252.114.255254
116158.252.115.0/24158.252.115.1 to 158.252.115.254158.252.115.255254
117158.252.116.0/24158.252.116.1 to 158.252.116.254158.252.116.255254
118158.252.117.0/24158.252.117.1 to 158.252.117.254158.252.117.255254
119158.252.118.0/24158.252.118.1 to 158.252.118.254158.252.118.255254
120158.252.119.0/24158.252.119.1 to 158.252.119.254158.252.119.255254
121158.252.120.0/24158.252.120.1 to 158.252.120.254158.252.120.255254
122158.252.121.0/24158.252.121.1 to 158.252.121.254158.252.121.255254
123158.252.122.0/24158.252.122.1 to 158.252.122.254158.252.122.255254
124158.252.123.0/24158.252.123.1 to 158.252.123.254158.252.123.255254
125158.252.124.0/24158.252.124.1 to 158.252.124.254158.252.124.255254
126158.252.125.0/24158.252.125.1 to 158.252.125.254158.252.125.255254
127158.252.126.0/24158.252.126.1 to 158.252.126.254158.252.126.255254
128158.252.127.0/24158.252.127.1 to 158.252.127.254158.252.127.255254
129158.252.128.0/24158.252.128.1 to 158.252.128.254158.252.128.255254
130158.252.129.0/24158.252.129.1 to 158.252.129.254158.252.129.255254
131158.252.130.0/24158.252.130.1 to 158.252.130.254158.252.130.255254
132158.252.131.0/24158.252.131.1 to 158.252.131.254158.252.131.255254
133158.252.132.0/24158.252.132.1 to 158.252.132.254158.252.132.255254
134158.252.133.0/24158.252.133.1 to 158.252.133.254158.252.133.255254
135158.252.134.0/24158.252.134.1 to 158.252.134.254158.252.134.255254
136158.252.135.0/24158.252.135.1 to 158.252.135.254158.252.135.255254
137158.252.136.0/24158.252.136.1 to 158.252.136.254158.252.136.255254
138158.252.137.0/24158.252.137.1 to 158.252.137.254158.252.137.255254
139158.252.138.0/24158.252.138.1 to 158.252.138.254158.252.138.255254
140158.252.139.0/24158.252.139.1 to 158.252.139.254158.252.139.255254
141158.252.140.0/24158.252.140.1 to 158.252.140.254158.252.140.255254
142158.252.141.0/24158.252.141.1 to 158.252.141.254158.252.141.255254
143158.252.142.0/24158.252.142.1 to 158.252.142.254158.252.142.255254
144158.252.143.0/24158.252.143.1 to 158.252.143.254158.252.143.255254
145158.252.144.0/24158.252.144.1 to 158.252.144.254158.252.144.255254
146158.252.145.0/24158.252.145.1 to 158.252.145.254158.252.145.255254
147158.252.146.0/24158.252.146.1 to 158.252.146.254158.252.146.255254
148158.252.147.0/24158.252.147.1 to 158.252.147.254158.252.147.255254
149158.252.148.0/24158.252.148.1 to 158.252.148.254158.252.148.255254
150158.252.149.0/24158.252.149.1 to 158.252.149.254158.252.149.255254
151158.252.150.0/24158.252.150.1 to 158.252.150.254158.252.150.255254
152158.252.151.0/24158.252.151.1 to 158.252.151.254158.252.151.255254
153158.252.152.0/24158.252.152.1 to 158.252.152.254158.252.152.255254
154158.252.153.0/24158.252.153.1 to 158.252.153.254158.252.153.255254
155158.252.154.0/24158.252.154.1 to 158.252.154.254158.252.154.255254
156158.252.155.0/24158.252.155.1 to 158.252.155.254158.252.155.255254
157158.252.156.0/24158.252.156.1 to 158.252.156.254158.252.156.255254
158158.252.157.0/24158.252.157.1 to 158.252.157.254158.252.157.255254
159158.252.158.0/24158.252.158.1 to 158.252.158.254158.252.158.255254
160158.252.159.0/24158.252.159.1 to 158.252.159.254158.252.159.255254
161158.252.160.0/24158.252.160.1 to 158.252.160.254158.252.160.255254
162158.252.161.0/24158.252.161.1 to 158.252.161.254158.252.161.255254
163158.252.162.0/24158.252.162.1 to 158.252.162.254158.252.162.255254
164158.252.163.0/24158.252.163.1 to 158.252.163.254158.252.163.255254
165158.252.164.0/24158.252.164.1 to 158.252.164.254158.252.164.255254
166158.252.165.0/24158.252.165.1 to 158.252.165.254158.252.165.255254
167158.252.166.0/24158.252.166.1 to 158.252.166.254158.252.166.255254
168158.252.167.0/24158.252.167.1 to 158.252.167.254158.252.167.255254
169158.252.168.0/24158.252.168.1 to 158.252.168.254158.252.168.255254
170158.252.169.0/24158.252.169.1 to 158.252.169.254158.252.169.255254
171158.252.170.0/24158.252.170.1 to 158.252.170.254158.252.170.255254
172158.252.171.0/24158.252.171.1 to 158.252.171.254158.252.171.255254
173158.252.172.0/24158.252.172.1 to 158.252.172.254158.252.172.255254
174158.252.173.0/24158.252.173.1 to 158.252.173.254158.252.173.255254
175158.252.174.0/24158.252.174.1 to 158.252.174.254158.252.174.255254
176158.252.175.0/24158.252.175.1 to 158.252.175.254158.252.175.255254
177158.252.176.0/24158.252.176.1 to 158.252.176.254158.252.176.255254
178158.252.177.0/24158.252.177.1 to 158.252.177.254158.252.177.255254
179158.252.178.0/24158.252.178.1 to 158.252.178.254158.252.178.255254
180158.252.179.0/24158.252.179.1 to 158.252.179.254158.252.179.255254
181158.252.180.0/24158.252.180.1 to 158.252.180.254158.252.180.255254
182158.252.181.0/24158.252.181.1 to 158.252.181.254158.252.181.255254
183158.252.182.0/24158.252.182.1 to 158.252.182.254158.252.182.255254
184158.252.183.0/24158.252.183.1 to 158.252.183.254158.252.183.255254
185158.252.184.0/24158.252.184.1 to 158.252.184.254158.252.184.255254
186158.252.185.0/24158.252.185.1 to 158.252.185.254158.252.185.255254
187158.252.186.0/24158.252.186.1 to 158.252.186.254158.252.186.255254
188158.252.187.0/24158.252.187.1 to 158.252.187.254158.252.187.255254
189158.252.188.0/24158.252.188.1 to 158.252.188.254158.252.188.255254
190158.252.189.0/24158.252.189.1 to 158.252.189.254158.252.189.255254
191158.252.190.0/24158.252.190.1 to 158.252.190.254158.252.190.255254
192158.252.191.0/24158.252.191.1 to 158.252.191.254158.252.191.255254
193158.252.192.0/24158.252.192.1 to 158.252.192.254158.252.192.255254
194158.252.193.0/24158.252.193.1 to 158.252.193.254158.252.193.255254
195158.252.194.0/24158.252.194.1 to 158.252.194.254158.252.194.255254
196158.252.195.0/24158.252.195.1 to 158.252.195.254158.252.195.255254
197158.252.196.0/24158.252.196.1 to 158.252.196.254158.252.196.255254
198158.252.197.0/24158.252.197.1 to 158.252.197.254158.252.197.255254
199158.252.198.0/24158.252.198.1 to 158.252.198.254158.252.198.255254
200158.252.199.0/24158.252.199.1 to 158.252.199.254158.252.199.255254
201158.252.200.0/24158.252.200.1 to 158.252.200.254158.252.200.255254
202158.252.201.0/24158.252.201.1 to 158.252.201.254158.252.201.255254
203158.252.202.0/24158.252.202.1 to 158.252.202.254158.252.202.255254
204158.252.203.0/24158.252.203.1 to 158.252.203.254158.252.203.255254
205158.252.204.0/24158.252.204.1 to 158.252.204.254158.252.204.255254
206158.252.205.0/24158.252.205.1 to 158.252.205.254158.252.205.255254
207158.252.206.0/24158.252.206.1 to 158.252.206.254158.252.206.255254
208158.252.207.0/24158.252.207.1 to 158.252.207.254158.252.207.255254
209158.252.208.0/24158.252.208.1 to 158.252.208.254158.252.208.255254
210158.252.209.0/24158.252.209.1 to 158.252.209.254158.252.209.255254
211158.252.210.0/24158.252.210.1 to 158.252.210.254158.252.210.255254
212158.252.211.0/24158.252.211.1 to 158.252.211.254158.252.211.255254
213158.252.212.0/24158.252.212.1 to 158.252.212.254158.252.212.255254
214158.252.213.0/24158.252.213.1 to 158.252.213.254158.252.213.255254
215158.252.214.0/24158.252.214.1 to 158.252.214.254158.252.214.255254
216158.252.215.0/24158.252.215.1 to 158.252.215.254158.252.215.255254
217158.252.216.0/24158.252.216.1 to 158.252.216.254158.252.216.255254
218158.252.217.0/24158.252.217.1 to 158.252.217.254158.252.217.255254
219158.252.218.0/24158.252.218.1 to 158.252.218.254158.252.218.255254
220158.252.219.0/24158.252.219.1 to 158.252.219.254158.252.219.255254
221158.252.220.0/24158.252.220.1 to 158.252.220.254158.252.220.255254
222158.252.221.0/24158.252.221.1 to 158.252.221.254158.252.221.255254
223158.252.222.0/24158.252.222.1 to 158.252.222.254158.252.222.255254
224158.252.223.0/24158.252.223.1 to 158.252.223.254158.252.223.255254
225158.252.224.0/24158.252.224.1 to 158.252.224.254158.252.224.255254
226158.252.225.0/24158.252.225.1 to 158.252.225.254158.252.225.255254
227158.252.226.0/24158.252.226.1 to 158.252.226.254158.252.226.255254
228158.252.227.0/24158.252.227.1 to 158.252.227.254158.252.227.255254
229158.252.228.0/24158.252.228.1 to 158.252.228.254158.252.228.255254
230158.252.229.0/24158.252.229.1 to 158.252.229.254158.252.229.255254
231158.252.230.0/24158.252.230.1 to 158.252.230.254158.252.230.255254
232158.252.231.0/24158.252.231.1 to 158.252.231.254158.252.231.255254
233158.252.232.0/24158.252.232.1 to 158.252.232.254158.252.232.255254
234158.252.233.0/24158.252.233.1 to 158.252.233.254158.252.233.255254
235158.252.234.0/24158.252.234.1 to 158.252.234.254158.252.234.255254
236158.252.235.0/24158.252.235.1 to 158.252.235.254158.252.235.255254
237158.252.236.0/24158.252.236.1 to 158.252.236.254158.252.236.255254
238158.252.237.0/24158.252.237.1 to 158.252.237.254158.252.237.255254
239158.252.238.0/24158.252.238.1 to 158.252.238.254158.252.238.255254
240158.252.239.0/24158.252.239.1 to 158.252.239.254158.252.239.255254
241158.252.240.0/24158.252.240.1 to 158.252.240.254158.252.240.255254
242158.252.241.0/24158.252.241.1 to 158.252.241.254158.252.241.255254
243158.252.242.0/24158.252.242.1 to 158.252.242.254158.252.242.255254
244158.252.243.0/24158.252.243.1 to 158.252.243.254158.252.243.255254
245158.252.244.0/24158.252.244.1 to 158.252.244.254158.252.244.255254
246158.252.245.0/24158.252.245.1 to 158.252.245.254158.252.245.255254
247158.252.246.0/24158.252.246.1 to 158.252.246.254158.252.246.255254
248158.252.247.0/24158.252.247.1 to 158.252.247.254158.252.247.255254
249158.252.248.0/24158.252.248.1 to 158.252.248.254158.252.248.255254
250158.252.249.0/24158.252.249.1 to 158.252.249.254158.252.249.255254
251158.252.250.0/24158.252.250.1 to 158.252.250.254158.252.250.255254
252158.252.251.0/24158.252.251.1 to 158.252.251.254158.252.251.255254
253158.252.252.0/24158.252.252.1 to 158.252.252.254158.252.252.255254
254158.252.253.0/24158.252.253.1 to 158.252.253.254158.252.253.255254
255158.252.254.0/24158.252.254.1 to 158.252.254.254158.252.254.255254
256158.252.255.0/24158.252.255.1 to 158.252.255.254158.252.255.255254

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.