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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.

Network143.192.0.0/13
Usable hosts524,286
Subnet mask255.248.0.0
Addresses524,288
Network address
143.192.0.0
Broadcast address
143.199.255.255
First usable
143.192.0.1
Last usable
143.199.255.254
Usable hosts
524,286 (524,288 less the network and broadcast addresses)
Subnet mask
255.248.0.0
Wildcard mask
0.7.255.255 (Cisco ACLs, OSPF)
Prefix length
/13
Type
Public public
Old class
B (default /16)
As numbers
Hex 8FC00000 · Integer 2411724800 to 2412249087
Reverse DNS zones
192.143.in-addr.arpa
193.143.in-addr.arpa
194.143.in-addr.arpa
195.143.in-addr.arpa
196.143.in-addr.arpa
197.143.in-addr.arpa
198.143.in-addr.arpa
199.143.in-addr.arpa
/13 is not on a 8-bit boundary, so it takes 8 /16 zones.
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address10001111.11000000.00000000.00000000143.192.0.0
Subnet mask11111111.11111000.00000000.00000000255.248.0.0
Network10001111.11000000.00000000.00000000143.192.0.0
Broadcast10001111.11000111.11111111.11111111143.199.255.255
Split into smaller subnets/24
/14 (2)/15 (4)/16 (8)/17 (16)/18 (32)/19 (64)/20 (128)/21 (256)/22 (512)/23 (1,024)/24 (2,048)/25 (4,096)

143.192.0.0/13 makes 2,048 subnets of /24; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
1143.192.0.0/24143.192.0.1 to 143.192.0.254143.192.0.255254
2143.192.1.0/24143.192.1.1 to 143.192.1.254143.192.1.255254
3143.192.2.0/24143.192.2.1 to 143.192.2.254143.192.2.255254
4143.192.3.0/24143.192.3.1 to 143.192.3.254143.192.3.255254
5143.192.4.0/24143.192.4.1 to 143.192.4.254143.192.4.255254
6143.192.5.0/24143.192.5.1 to 143.192.5.254143.192.5.255254
7143.192.6.0/24143.192.6.1 to 143.192.6.254143.192.6.255254
8143.192.7.0/24143.192.7.1 to 143.192.7.254143.192.7.255254
9143.192.8.0/24143.192.8.1 to 143.192.8.254143.192.8.255254
10143.192.9.0/24143.192.9.1 to 143.192.9.254143.192.9.255254
11143.192.10.0/24143.192.10.1 to 143.192.10.254143.192.10.255254
12143.192.11.0/24143.192.11.1 to 143.192.11.254143.192.11.255254
13143.192.12.0/24143.192.12.1 to 143.192.12.254143.192.12.255254
14143.192.13.0/24143.192.13.1 to 143.192.13.254143.192.13.255254
15143.192.14.0/24143.192.14.1 to 143.192.14.254143.192.14.255254
16143.192.15.0/24143.192.15.1 to 143.192.15.254143.192.15.255254
17143.192.16.0/24143.192.16.1 to 143.192.16.254143.192.16.255254
18143.192.17.0/24143.192.17.1 to 143.192.17.254143.192.17.255254
19143.192.18.0/24143.192.18.1 to 143.192.18.254143.192.18.255254
20143.192.19.0/24143.192.19.1 to 143.192.19.254143.192.19.255254
21143.192.20.0/24143.192.20.1 to 143.192.20.254143.192.20.255254
22143.192.21.0/24143.192.21.1 to 143.192.21.254143.192.21.255254
23143.192.22.0/24143.192.22.1 to 143.192.22.254143.192.22.255254
24143.192.23.0/24143.192.23.1 to 143.192.23.254143.192.23.255254
25143.192.24.0/24143.192.24.1 to 143.192.24.254143.192.24.255254
26143.192.25.0/24143.192.25.1 to 143.192.25.254143.192.25.255254
27143.192.26.0/24143.192.26.1 to 143.192.26.254143.192.26.255254
28143.192.27.0/24143.192.27.1 to 143.192.27.254143.192.27.255254
29143.192.28.0/24143.192.28.1 to 143.192.28.254143.192.28.255254
30143.192.29.0/24143.192.29.1 to 143.192.29.254143.192.29.255254
31143.192.30.0/24143.192.30.1 to 143.192.30.254143.192.30.255254
32143.192.31.0/24143.192.31.1 to 143.192.31.254143.192.31.255254
33143.192.32.0/24143.192.32.1 to 143.192.32.254143.192.32.255254
34143.192.33.0/24143.192.33.1 to 143.192.33.254143.192.33.255254
35143.192.34.0/24143.192.34.1 to 143.192.34.254143.192.34.255254
36143.192.35.0/24143.192.35.1 to 143.192.35.254143.192.35.255254
37143.192.36.0/24143.192.36.1 to 143.192.36.254143.192.36.255254
38143.192.37.0/24143.192.37.1 to 143.192.37.254143.192.37.255254
39143.192.38.0/24143.192.38.1 to 143.192.38.254143.192.38.255254
40143.192.39.0/24143.192.39.1 to 143.192.39.254143.192.39.255254
41143.192.40.0/24143.192.40.1 to 143.192.40.254143.192.40.255254
42143.192.41.0/24143.192.41.1 to 143.192.41.254143.192.41.255254
43143.192.42.0/24143.192.42.1 to 143.192.42.254143.192.42.255254
44143.192.43.0/24143.192.43.1 to 143.192.43.254143.192.43.255254
45143.192.44.0/24143.192.44.1 to 143.192.44.254143.192.44.255254
46143.192.45.0/24143.192.45.1 to 143.192.45.254143.192.45.255254
47143.192.46.0/24143.192.46.1 to 143.192.46.254143.192.46.255254
48143.192.47.0/24143.192.47.1 to 143.192.47.254143.192.47.255254
49143.192.48.0/24143.192.48.1 to 143.192.48.254143.192.48.255254
50143.192.49.0/24143.192.49.1 to 143.192.49.254143.192.49.255254
51143.192.50.0/24143.192.50.1 to 143.192.50.254143.192.50.255254
52143.192.51.0/24143.192.51.1 to 143.192.51.254143.192.51.255254
53143.192.52.0/24143.192.52.1 to 143.192.52.254143.192.52.255254
54143.192.53.0/24143.192.53.1 to 143.192.53.254143.192.53.255254
55143.192.54.0/24143.192.54.1 to 143.192.54.254143.192.54.255254
56143.192.55.0/24143.192.55.1 to 143.192.55.254143.192.55.255254
57143.192.56.0/24143.192.56.1 to 143.192.56.254143.192.56.255254
58143.192.57.0/24143.192.57.1 to 143.192.57.254143.192.57.255254
59143.192.58.0/24143.192.58.1 to 143.192.58.254143.192.58.255254
60143.192.59.0/24143.192.59.1 to 143.192.59.254143.192.59.255254
61143.192.60.0/24143.192.60.1 to 143.192.60.254143.192.60.255254
62143.192.61.0/24143.192.61.1 to 143.192.61.254143.192.61.255254
63143.192.62.0/24143.192.62.1 to 143.192.62.254143.192.62.255254
64143.192.63.0/24143.192.63.1 to 143.192.63.254143.192.63.255254
65143.192.64.0/24143.192.64.1 to 143.192.64.254143.192.64.255254
66143.192.65.0/24143.192.65.1 to 143.192.65.254143.192.65.255254
67143.192.66.0/24143.192.66.1 to 143.192.66.254143.192.66.255254
68143.192.67.0/24143.192.67.1 to 143.192.67.254143.192.67.255254
69143.192.68.0/24143.192.68.1 to 143.192.68.254143.192.68.255254
70143.192.69.0/24143.192.69.1 to 143.192.69.254143.192.69.255254
71143.192.70.0/24143.192.70.1 to 143.192.70.254143.192.70.255254
72143.192.71.0/24143.192.71.1 to 143.192.71.254143.192.71.255254
73143.192.72.0/24143.192.72.1 to 143.192.72.254143.192.72.255254
74143.192.73.0/24143.192.73.1 to 143.192.73.254143.192.73.255254
75143.192.74.0/24143.192.74.1 to 143.192.74.254143.192.74.255254
76143.192.75.0/24143.192.75.1 to 143.192.75.254143.192.75.255254
77143.192.76.0/24143.192.76.1 to 143.192.76.254143.192.76.255254
78143.192.77.0/24143.192.77.1 to 143.192.77.254143.192.77.255254
79143.192.78.0/24143.192.78.1 to 143.192.78.254143.192.78.255254
80143.192.79.0/24143.192.79.1 to 143.192.79.254143.192.79.255254
81143.192.80.0/24143.192.80.1 to 143.192.80.254143.192.80.255254
82143.192.81.0/24143.192.81.1 to 143.192.81.254143.192.81.255254
83143.192.82.0/24143.192.82.1 to 143.192.82.254143.192.82.255254
84143.192.83.0/24143.192.83.1 to 143.192.83.254143.192.83.255254
85143.192.84.0/24143.192.84.1 to 143.192.84.254143.192.84.255254
86143.192.85.0/24143.192.85.1 to 143.192.85.254143.192.85.255254
87143.192.86.0/24143.192.86.1 to 143.192.86.254143.192.86.255254
88143.192.87.0/24143.192.87.1 to 143.192.87.254143.192.87.255254
89143.192.88.0/24143.192.88.1 to 143.192.88.254143.192.88.255254
90143.192.89.0/24143.192.89.1 to 143.192.89.254143.192.89.255254
91143.192.90.0/24143.192.90.1 to 143.192.90.254143.192.90.255254
92143.192.91.0/24143.192.91.1 to 143.192.91.254143.192.91.255254
93143.192.92.0/24143.192.92.1 to 143.192.92.254143.192.92.255254
94143.192.93.0/24143.192.93.1 to 143.192.93.254143.192.93.255254
95143.192.94.0/24143.192.94.1 to 143.192.94.254143.192.94.255254
96143.192.95.0/24143.192.95.1 to 143.192.95.254143.192.95.255254
97143.192.96.0/24143.192.96.1 to 143.192.96.254143.192.96.255254
98143.192.97.0/24143.192.97.1 to 143.192.97.254143.192.97.255254
99143.192.98.0/24143.192.98.1 to 143.192.98.254143.192.98.255254
100143.192.99.0/24143.192.99.1 to 143.192.99.254143.192.99.255254
101143.192.100.0/24143.192.100.1 to 143.192.100.254143.192.100.255254
102143.192.101.0/24143.192.101.1 to 143.192.101.254143.192.101.255254
103143.192.102.0/24143.192.102.1 to 143.192.102.254143.192.102.255254
104143.192.103.0/24143.192.103.1 to 143.192.103.254143.192.103.255254
105143.192.104.0/24143.192.104.1 to 143.192.104.254143.192.104.255254
106143.192.105.0/24143.192.105.1 to 143.192.105.254143.192.105.255254
107143.192.106.0/24143.192.106.1 to 143.192.106.254143.192.106.255254
108143.192.107.0/24143.192.107.1 to 143.192.107.254143.192.107.255254
109143.192.108.0/24143.192.108.1 to 143.192.108.254143.192.108.255254
110143.192.109.0/24143.192.109.1 to 143.192.109.254143.192.109.255254
111143.192.110.0/24143.192.110.1 to 143.192.110.254143.192.110.255254
112143.192.111.0/24143.192.111.1 to 143.192.111.254143.192.111.255254
113143.192.112.0/24143.192.112.1 to 143.192.112.254143.192.112.255254
114143.192.113.0/24143.192.113.1 to 143.192.113.254143.192.113.255254
115143.192.114.0/24143.192.114.1 to 143.192.114.254143.192.114.255254
116143.192.115.0/24143.192.115.1 to 143.192.115.254143.192.115.255254
117143.192.116.0/24143.192.116.1 to 143.192.116.254143.192.116.255254
118143.192.117.0/24143.192.117.1 to 143.192.117.254143.192.117.255254
119143.192.118.0/24143.192.118.1 to 143.192.118.254143.192.118.255254
120143.192.119.0/24143.192.119.1 to 143.192.119.254143.192.119.255254
121143.192.120.0/24143.192.120.1 to 143.192.120.254143.192.120.255254
122143.192.121.0/24143.192.121.1 to 143.192.121.254143.192.121.255254
123143.192.122.0/24143.192.122.1 to 143.192.122.254143.192.122.255254
124143.192.123.0/24143.192.123.1 to 143.192.123.254143.192.123.255254
125143.192.124.0/24143.192.124.1 to 143.192.124.254143.192.124.255254
126143.192.125.0/24143.192.125.1 to 143.192.125.254143.192.125.255254
127143.192.126.0/24143.192.126.1 to 143.192.126.254143.192.126.255254
128143.192.127.0/24143.192.127.1 to 143.192.127.254143.192.127.255254
129143.192.128.0/24143.192.128.1 to 143.192.128.254143.192.128.255254
130143.192.129.0/24143.192.129.1 to 143.192.129.254143.192.129.255254
131143.192.130.0/24143.192.130.1 to 143.192.130.254143.192.130.255254
132143.192.131.0/24143.192.131.1 to 143.192.131.254143.192.131.255254
133143.192.132.0/24143.192.132.1 to 143.192.132.254143.192.132.255254
134143.192.133.0/24143.192.133.1 to 143.192.133.254143.192.133.255254
135143.192.134.0/24143.192.134.1 to 143.192.134.254143.192.134.255254
136143.192.135.0/24143.192.135.1 to 143.192.135.254143.192.135.255254
137143.192.136.0/24143.192.136.1 to 143.192.136.254143.192.136.255254
138143.192.137.0/24143.192.137.1 to 143.192.137.254143.192.137.255254
139143.192.138.0/24143.192.138.1 to 143.192.138.254143.192.138.255254
140143.192.139.0/24143.192.139.1 to 143.192.139.254143.192.139.255254
141143.192.140.0/24143.192.140.1 to 143.192.140.254143.192.140.255254
142143.192.141.0/24143.192.141.1 to 143.192.141.254143.192.141.255254
143143.192.142.0/24143.192.142.1 to 143.192.142.254143.192.142.255254
144143.192.143.0/24143.192.143.1 to 143.192.143.254143.192.143.255254
145143.192.144.0/24143.192.144.1 to 143.192.144.254143.192.144.255254
146143.192.145.0/24143.192.145.1 to 143.192.145.254143.192.145.255254
147143.192.146.0/24143.192.146.1 to 143.192.146.254143.192.146.255254
148143.192.147.0/24143.192.147.1 to 143.192.147.254143.192.147.255254
149143.192.148.0/24143.192.148.1 to 143.192.148.254143.192.148.255254
150143.192.149.0/24143.192.149.1 to 143.192.149.254143.192.149.255254
151143.192.150.0/24143.192.150.1 to 143.192.150.254143.192.150.255254
152143.192.151.0/24143.192.151.1 to 143.192.151.254143.192.151.255254
153143.192.152.0/24143.192.152.1 to 143.192.152.254143.192.152.255254
154143.192.153.0/24143.192.153.1 to 143.192.153.254143.192.153.255254
155143.192.154.0/24143.192.154.1 to 143.192.154.254143.192.154.255254
156143.192.155.0/24143.192.155.1 to 143.192.155.254143.192.155.255254
157143.192.156.0/24143.192.156.1 to 143.192.156.254143.192.156.255254
158143.192.157.0/24143.192.157.1 to 143.192.157.254143.192.157.255254
159143.192.158.0/24143.192.158.1 to 143.192.158.254143.192.158.255254
160143.192.159.0/24143.192.159.1 to 143.192.159.254143.192.159.255254
161143.192.160.0/24143.192.160.1 to 143.192.160.254143.192.160.255254
162143.192.161.0/24143.192.161.1 to 143.192.161.254143.192.161.255254
163143.192.162.0/24143.192.162.1 to 143.192.162.254143.192.162.255254
164143.192.163.0/24143.192.163.1 to 143.192.163.254143.192.163.255254
165143.192.164.0/24143.192.164.1 to 143.192.164.254143.192.164.255254
166143.192.165.0/24143.192.165.1 to 143.192.165.254143.192.165.255254
167143.192.166.0/24143.192.166.1 to 143.192.166.254143.192.166.255254
168143.192.167.0/24143.192.167.1 to 143.192.167.254143.192.167.255254
169143.192.168.0/24143.192.168.1 to 143.192.168.254143.192.168.255254
170143.192.169.0/24143.192.169.1 to 143.192.169.254143.192.169.255254
171143.192.170.0/24143.192.170.1 to 143.192.170.254143.192.170.255254
172143.192.171.0/24143.192.171.1 to 143.192.171.254143.192.171.255254
173143.192.172.0/24143.192.172.1 to 143.192.172.254143.192.172.255254
174143.192.173.0/24143.192.173.1 to 143.192.173.254143.192.173.255254
175143.192.174.0/24143.192.174.1 to 143.192.174.254143.192.174.255254
176143.192.175.0/24143.192.175.1 to 143.192.175.254143.192.175.255254
177143.192.176.0/24143.192.176.1 to 143.192.176.254143.192.176.255254
178143.192.177.0/24143.192.177.1 to 143.192.177.254143.192.177.255254
179143.192.178.0/24143.192.178.1 to 143.192.178.254143.192.178.255254
180143.192.179.0/24143.192.179.1 to 143.192.179.254143.192.179.255254
181143.192.180.0/24143.192.180.1 to 143.192.180.254143.192.180.255254
182143.192.181.0/24143.192.181.1 to 143.192.181.254143.192.181.255254
183143.192.182.0/24143.192.182.1 to 143.192.182.254143.192.182.255254
184143.192.183.0/24143.192.183.1 to 143.192.183.254143.192.183.255254
185143.192.184.0/24143.192.184.1 to 143.192.184.254143.192.184.255254
186143.192.185.0/24143.192.185.1 to 143.192.185.254143.192.185.255254
187143.192.186.0/24143.192.186.1 to 143.192.186.254143.192.186.255254
188143.192.187.0/24143.192.187.1 to 143.192.187.254143.192.187.255254
189143.192.188.0/24143.192.188.1 to 143.192.188.254143.192.188.255254
190143.192.189.0/24143.192.189.1 to 143.192.189.254143.192.189.255254
191143.192.190.0/24143.192.190.1 to 143.192.190.254143.192.190.255254
192143.192.191.0/24143.192.191.1 to 143.192.191.254143.192.191.255254
193143.192.192.0/24143.192.192.1 to 143.192.192.254143.192.192.255254
194143.192.193.0/24143.192.193.1 to 143.192.193.254143.192.193.255254
195143.192.194.0/24143.192.194.1 to 143.192.194.254143.192.194.255254
196143.192.195.0/24143.192.195.1 to 143.192.195.254143.192.195.255254
197143.192.196.0/24143.192.196.1 to 143.192.196.254143.192.196.255254
198143.192.197.0/24143.192.197.1 to 143.192.197.254143.192.197.255254
199143.192.198.0/24143.192.198.1 to 143.192.198.254143.192.198.255254
200143.192.199.0/24143.192.199.1 to 143.192.199.254143.192.199.255254
201143.192.200.0/24143.192.200.1 to 143.192.200.254143.192.200.255254
202143.192.201.0/24143.192.201.1 to 143.192.201.254143.192.201.255254
203143.192.202.0/24143.192.202.1 to 143.192.202.254143.192.202.255254
204143.192.203.0/24143.192.203.1 to 143.192.203.254143.192.203.255254
205143.192.204.0/24143.192.204.1 to 143.192.204.254143.192.204.255254
206143.192.205.0/24143.192.205.1 to 143.192.205.254143.192.205.255254
207143.192.206.0/24143.192.206.1 to 143.192.206.254143.192.206.255254
208143.192.207.0/24143.192.207.1 to 143.192.207.254143.192.207.255254
209143.192.208.0/24143.192.208.1 to 143.192.208.254143.192.208.255254
210143.192.209.0/24143.192.209.1 to 143.192.209.254143.192.209.255254
211143.192.210.0/24143.192.210.1 to 143.192.210.254143.192.210.255254
212143.192.211.0/24143.192.211.1 to 143.192.211.254143.192.211.255254
213143.192.212.0/24143.192.212.1 to 143.192.212.254143.192.212.255254
214143.192.213.0/24143.192.213.1 to 143.192.213.254143.192.213.255254
215143.192.214.0/24143.192.214.1 to 143.192.214.254143.192.214.255254
216143.192.215.0/24143.192.215.1 to 143.192.215.254143.192.215.255254
217143.192.216.0/24143.192.216.1 to 143.192.216.254143.192.216.255254
218143.192.217.0/24143.192.217.1 to 143.192.217.254143.192.217.255254
219143.192.218.0/24143.192.218.1 to 143.192.218.254143.192.218.255254
220143.192.219.0/24143.192.219.1 to 143.192.219.254143.192.219.255254
221143.192.220.0/24143.192.220.1 to 143.192.220.254143.192.220.255254
222143.192.221.0/24143.192.221.1 to 143.192.221.254143.192.221.255254
223143.192.222.0/24143.192.222.1 to 143.192.222.254143.192.222.255254
224143.192.223.0/24143.192.223.1 to 143.192.223.254143.192.223.255254
225143.192.224.0/24143.192.224.1 to 143.192.224.254143.192.224.255254
226143.192.225.0/24143.192.225.1 to 143.192.225.254143.192.225.255254
227143.192.226.0/24143.192.226.1 to 143.192.226.254143.192.226.255254
228143.192.227.0/24143.192.227.1 to 143.192.227.254143.192.227.255254
229143.192.228.0/24143.192.228.1 to 143.192.228.254143.192.228.255254
230143.192.229.0/24143.192.229.1 to 143.192.229.254143.192.229.255254
231143.192.230.0/24143.192.230.1 to 143.192.230.254143.192.230.255254
232143.192.231.0/24143.192.231.1 to 143.192.231.254143.192.231.255254
233143.192.232.0/24143.192.232.1 to 143.192.232.254143.192.232.255254
234143.192.233.0/24143.192.233.1 to 143.192.233.254143.192.233.255254
235143.192.234.0/24143.192.234.1 to 143.192.234.254143.192.234.255254
236143.192.235.0/24143.192.235.1 to 143.192.235.254143.192.235.255254
237143.192.236.0/24143.192.236.1 to 143.192.236.254143.192.236.255254
238143.192.237.0/24143.192.237.1 to 143.192.237.254143.192.237.255254
239143.192.238.0/24143.192.238.1 to 143.192.238.254143.192.238.255254
240143.192.239.0/24143.192.239.1 to 143.192.239.254143.192.239.255254
241143.192.240.0/24143.192.240.1 to 143.192.240.254143.192.240.255254
242143.192.241.0/24143.192.241.1 to 143.192.241.254143.192.241.255254
243143.192.242.0/24143.192.242.1 to 143.192.242.254143.192.242.255254
244143.192.243.0/24143.192.243.1 to 143.192.243.254143.192.243.255254
245143.192.244.0/24143.192.244.1 to 143.192.244.254143.192.244.255254
246143.192.245.0/24143.192.245.1 to 143.192.245.254143.192.245.255254
247143.192.246.0/24143.192.246.1 to 143.192.246.254143.192.246.255254
248143.192.247.0/24143.192.247.1 to 143.192.247.254143.192.247.255254
249143.192.248.0/24143.192.248.1 to 143.192.248.254143.192.248.255254
250143.192.249.0/24143.192.249.1 to 143.192.249.254143.192.249.255254
251143.192.250.0/24143.192.250.1 to 143.192.250.254143.192.250.255254
252143.192.251.0/24143.192.251.1 to 143.192.251.254143.192.251.255254
253143.192.252.0/24143.192.252.1 to 143.192.252.254143.192.252.255254
254143.192.253.0/24143.192.253.1 to 143.192.253.254143.192.253.255254
255143.192.254.0/24143.192.254.1 to 143.192.254.254143.192.254.255254
256143.192.255.0/24143.192.255.1 to 143.192.255.254143.192.255.255254

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.