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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.

Network157.152.0.0/13
Usable hosts524,286
Subnet mask255.248.0.0
Addresses524,288
Network address
157.152.0.0
Broadcast address
157.159.255.255
First usable
157.152.0.1
Last usable
157.159.255.254
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 9D980000 · Integer 2643984384 to 2644508671
Reverse DNS zones
152.157.in-addr.arpa
153.157.in-addr.arpa
154.157.in-addr.arpa
155.157.in-addr.arpa
156.157.in-addr.arpa
157.157.in-addr.arpa
158.157.in-addr.arpa
159.157.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
Address10011101.10011000.00000000.00000000157.152.0.0
Subnet mask11111111.11111000.00000000.00000000255.248.0.0
Network10011101.10011000.00000000.00000000157.152.0.0
Broadcast10011101.10011111.11111111.11111111157.159.255.255
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)

157.152.0.0/13 makes 2,048 subnets of /24; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
1157.152.0.0/24157.152.0.1 to 157.152.0.254157.152.0.255254
2157.152.1.0/24157.152.1.1 to 157.152.1.254157.152.1.255254
3157.152.2.0/24157.152.2.1 to 157.152.2.254157.152.2.255254
4157.152.3.0/24157.152.3.1 to 157.152.3.254157.152.3.255254
5157.152.4.0/24157.152.4.1 to 157.152.4.254157.152.4.255254
6157.152.5.0/24157.152.5.1 to 157.152.5.254157.152.5.255254
7157.152.6.0/24157.152.6.1 to 157.152.6.254157.152.6.255254
8157.152.7.0/24157.152.7.1 to 157.152.7.254157.152.7.255254
9157.152.8.0/24157.152.8.1 to 157.152.8.254157.152.8.255254
10157.152.9.0/24157.152.9.1 to 157.152.9.254157.152.9.255254
11157.152.10.0/24157.152.10.1 to 157.152.10.254157.152.10.255254
12157.152.11.0/24157.152.11.1 to 157.152.11.254157.152.11.255254
13157.152.12.0/24157.152.12.1 to 157.152.12.254157.152.12.255254
14157.152.13.0/24157.152.13.1 to 157.152.13.254157.152.13.255254
15157.152.14.0/24157.152.14.1 to 157.152.14.254157.152.14.255254
16157.152.15.0/24157.152.15.1 to 157.152.15.254157.152.15.255254
17157.152.16.0/24157.152.16.1 to 157.152.16.254157.152.16.255254
18157.152.17.0/24157.152.17.1 to 157.152.17.254157.152.17.255254
19157.152.18.0/24157.152.18.1 to 157.152.18.254157.152.18.255254
20157.152.19.0/24157.152.19.1 to 157.152.19.254157.152.19.255254
21157.152.20.0/24157.152.20.1 to 157.152.20.254157.152.20.255254
22157.152.21.0/24157.152.21.1 to 157.152.21.254157.152.21.255254
23157.152.22.0/24157.152.22.1 to 157.152.22.254157.152.22.255254
24157.152.23.0/24157.152.23.1 to 157.152.23.254157.152.23.255254
25157.152.24.0/24157.152.24.1 to 157.152.24.254157.152.24.255254
26157.152.25.0/24157.152.25.1 to 157.152.25.254157.152.25.255254
27157.152.26.0/24157.152.26.1 to 157.152.26.254157.152.26.255254
28157.152.27.0/24157.152.27.1 to 157.152.27.254157.152.27.255254
29157.152.28.0/24157.152.28.1 to 157.152.28.254157.152.28.255254
30157.152.29.0/24157.152.29.1 to 157.152.29.254157.152.29.255254
31157.152.30.0/24157.152.30.1 to 157.152.30.254157.152.30.255254
32157.152.31.0/24157.152.31.1 to 157.152.31.254157.152.31.255254
33157.152.32.0/24157.152.32.1 to 157.152.32.254157.152.32.255254
34157.152.33.0/24157.152.33.1 to 157.152.33.254157.152.33.255254
35157.152.34.0/24157.152.34.1 to 157.152.34.254157.152.34.255254
36157.152.35.0/24157.152.35.1 to 157.152.35.254157.152.35.255254
37157.152.36.0/24157.152.36.1 to 157.152.36.254157.152.36.255254
38157.152.37.0/24157.152.37.1 to 157.152.37.254157.152.37.255254
39157.152.38.0/24157.152.38.1 to 157.152.38.254157.152.38.255254
40157.152.39.0/24157.152.39.1 to 157.152.39.254157.152.39.255254
41157.152.40.0/24157.152.40.1 to 157.152.40.254157.152.40.255254
42157.152.41.0/24157.152.41.1 to 157.152.41.254157.152.41.255254
43157.152.42.0/24157.152.42.1 to 157.152.42.254157.152.42.255254
44157.152.43.0/24157.152.43.1 to 157.152.43.254157.152.43.255254
45157.152.44.0/24157.152.44.1 to 157.152.44.254157.152.44.255254
46157.152.45.0/24157.152.45.1 to 157.152.45.254157.152.45.255254
47157.152.46.0/24157.152.46.1 to 157.152.46.254157.152.46.255254
48157.152.47.0/24157.152.47.1 to 157.152.47.254157.152.47.255254
49157.152.48.0/24157.152.48.1 to 157.152.48.254157.152.48.255254
50157.152.49.0/24157.152.49.1 to 157.152.49.254157.152.49.255254
51157.152.50.0/24157.152.50.1 to 157.152.50.254157.152.50.255254
52157.152.51.0/24157.152.51.1 to 157.152.51.254157.152.51.255254
53157.152.52.0/24157.152.52.1 to 157.152.52.254157.152.52.255254
54157.152.53.0/24157.152.53.1 to 157.152.53.254157.152.53.255254
55157.152.54.0/24157.152.54.1 to 157.152.54.254157.152.54.255254
56157.152.55.0/24157.152.55.1 to 157.152.55.254157.152.55.255254
57157.152.56.0/24157.152.56.1 to 157.152.56.254157.152.56.255254
58157.152.57.0/24157.152.57.1 to 157.152.57.254157.152.57.255254
59157.152.58.0/24157.152.58.1 to 157.152.58.254157.152.58.255254
60157.152.59.0/24157.152.59.1 to 157.152.59.254157.152.59.255254
61157.152.60.0/24157.152.60.1 to 157.152.60.254157.152.60.255254
62157.152.61.0/24157.152.61.1 to 157.152.61.254157.152.61.255254
63157.152.62.0/24157.152.62.1 to 157.152.62.254157.152.62.255254
64157.152.63.0/24157.152.63.1 to 157.152.63.254157.152.63.255254
65157.152.64.0/24157.152.64.1 to 157.152.64.254157.152.64.255254
66157.152.65.0/24157.152.65.1 to 157.152.65.254157.152.65.255254
67157.152.66.0/24157.152.66.1 to 157.152.66.254157.152.66.255254
68157.152.67.0/24157.152.67.1 to 157.152.67.254157.152.67.255254
69157.152.68.0/24157.152.68.1 to 157.152.68.254157.152.68.255254
70157.152.69.0/24157.152.69.1 to 157.152.69.254157.152.69.255254
71157.152.70.0/24157.152.70.1 to 157.152.70.254157.152.70.255254
72157.152.71.0/24157.152.71.1 to 157.152.71.254157.152.71.255254
73157.152.72.0/24157.152.72.1 to 157.152.72.254157.152.72.255254
74157.152.73.0/24157.152.73.1 to 157.152.73.254157.152.73.255254
75157.152.74.0/24157.152.74.1 to 157.152.74.254157.152.74.255254
76157.152.75.0/24157.152.75.1 to 157.152.75.254157.152.75.255254
77157.152.76.0/24157.152.76.1 to 157.152.76.254157.152.76.255254
78157.152.77.0/24157.152.77.1 to 157.152.77.254157.152.77.255254
79157.152.78.0/24157.152.78.1 to 157.152.78.254157.152.78.255254
80157.152.79.0/24157.152.79.1 to 157.152.79.254157.152.79.255254
81157.152.80.0/24157.152.80.1 to 157.152.80.254157.152.80.255254
82157.152.81.0/24157.152.81.1 to 157.152.81.254157.152.81.255254
83157.152.82.0/24157.152.82.1 to 157.152.82.254157.152.82.255254
84157.152.83.0/24157.152.83.1 to 157.152.83.254157.152.83.255254
85157.152.84.0/24157.152.84.1 to 157.152.84.254157.152.84.255254
86157.152.85.0/24157.152.85.1 to 157.152.85.254157.152.85.255254
87157.152.86.0/24157.152.86.1 to 157.152.86.254157.152.86.255254
88157.152.87.0/24157.152.87.1 to 157.152.87.254157.152.87.255254
89157.152.88.0/24157.152.88.1 to 157.152.88.254157.152.88.255254
90157.152.89.0/24157.152.89.1 to 157.152.89.254157.152.89.255254
91157.152.90.0/24157.152.90.1 to 157.152.90.254157.152.90.255254
92157.152.91.0/24157.152.91.1 to 157.152.91.254157.152.91.255254
93157.152.92.0/24157.152.92.1 to 157.152.92.254157.152.92.255254
94157.152.93.0/24157.152.93.1 to 157.152.93.254157.152.93.255254
95157.152.94.0/24157.152.94.1 to 157.152.94.254157.152.94.255254
96157.152.95.0/24157.152.95.1 to 157.152.95.254157.152.95.255254
97157.152.96.0/24157.152.96.1 to 157.152.96.254157.152.96.255254
98157.152.97.0/24157.152.97.1 to 157.152.97.254157.152.97.255254
99157.152.98.0/24157.152.98.1 to 157.152.98.254157.152.98.255254
100157.152.99.0/24157.152.99.1 to 157.152.99.254157.152.99.255254
101157.152.100.0/24157.152.100.1 to 157.152.100.254157.152.100.255254
102157.152.101.0/24157.152.101.1 to 157.152.101.254157.152.101.255254
103157.152.102.0/24157.152.102.1 to 157.152.102.254157.152.102.255254
104157.152.103.0/24157.152.103.1 to 157.152.103.254157.152.103.255254
105157.152.104.0/24157.152.104.1 to 157.152.104.254157.152.104.255254
106157.152.105.0/24157.152.105.1 to 157.152.105.254157.152.105.255254
107157.152.106.0/24157.152.106.1 to 157.152.106.254157.152.106.255254
108157.152.107.0/24157.152.107.1 to 157.152.107.254157.152.107.255254
109157.152.108.0/24157.152.108.1 to 157.152.108.254157.152.108.255254
110157.152.109.0/24157.152.109.1 to 157.152.109.254157.152.109.255254
111157.152.110.0/24157.152.110.1 to 157.152.110.254157.152.110.255254
112157.152.111.0/24157.152.111.1 to 157.152.111.254157.152.111.255254
113157.152.112.0/24157.152.112.1 to 157.152.112.254157.152.112.255254
114157.152.113.0/24157.152.113.1 to 157.152.113.254157.152.113.255254
115157.152.114.0/24157.152.114.1 to 157.152.114.254157.152.114.255254
116157.152.115.0/24157.152.115.1 to 157.152.115.254157.152.115.255254
117157.152.116.0/24157.152.116.1 to 157.152.116.254157.152.116.255254
118157.152.117.0/24157.152.117.1 to 157.152.117.254157.152.117.255254
119157.152.118.0/24157.152.118.1 to 157.152.118.254157.152.118.255254
120157.152.119.0/24157.152.119.1 to 157.152.119.254157.152.119.255254
121157.152.120.0/24157.152.120.1 to 157.152.120.254157.152.120.255254
122157.152.121.0/24157.152.121.1 to 157.152.121.254157.152.121.255254
123157.152.122.0/24157.152.122.1 to 157.152.122.254157.152.122.255254
124157.152.123.0/24157.152.123.1 to 157.152.123.254157.152.123.255254
125157.152.124.0/24157.152.124.1 to 157.152.124.254157.152.124.255254
126157.152.125.0/24157.152.125.1 to 157.152.125.254157.152.125.255254
127157.152.126.0/24157.152.126.1 to 157.152.126.254157.152.126.255254
128157.152.127.0/24157.152.127.1 to 157.152.127.254157.152.127.255254
129157.152.128.0/24157.152.128.1 to 157.152.128.254157.152.128.255254
130157.152.129.0/24157.152.129.1 to 157.152.129.254157.152.129.255254
131157.152.130.0/24157.152.130.1 to 157.152.130.254157.152.130.255254
132157.152.131.0/24157.152.131.1 to 157.152.131.254157.152.131.255254
133157.152.132.0/24157.152.132.1 to 157.152.132.254157.152.132.255254
134157.152.133.0/24157.152.133.1 to 157.152.133.254157.152.133.255254
135157.152.134.0/24157.152.134.1 to 157.152.134.254157.152.134.255254
136157.152.135.0/24157.152.135.1 to 157.152.135.254157.152.135.255254
137157.152.136.0/24157.152.136.1 to 157.152.136.254157.152.136.255254
138157.152.137.0/24157.152.137.1 to 157.152.137.254157.152.137.255254
139157.152.138.0/24157.152.138.1 to 157.152.138.254157.152.138.255254
140157.152.139.0/24157.152.139.1 to 157.152.139.254157.152.139.255254
141157.152.140.0/24157.152.140.1 to 157.152.140.254157.152.140.255254
142157.152.141.0/24157.152.141.1 to 157.152.141.254157.152.141.255254
143157.152.142.0/24157.152.142.1 to 157.152.142.254157.152.142.255254
144157.152.143.0/24157.152.143.1 to 157.152.143.254157.152.143.255254
145157.152.144.0/24157.152.144.1 to 157.152.144.254157.152.144.255254
146157.152.145.0/24157.152.145.1 to 157.152.145.254157.152.145.255254
147157.152.146.0/24157.152.146.1 to 157.152.146.254157.152.146.255254
148157.152.147.0/24157.152.147.1 to 157.152.147.254157.152.147.255254
149157.152.148.0/24157.152.148.1 to 157.152.148.254157.152.148.255254
150157.152.149.0/24157.152.149.1 to 157.152.149.254157.152.149.255254
151157.152.150.0/24157.152.150.1 to 157.152.150.254157.152.150.255254
152157.152.151.0/24157.152.151.1 to 157.152.151.254157.152.151.255254
153157.152.152.0/24157.152.152.1 to 157.152.152.254157.152.152.255254
154157.152.153.0/24157.152.153.1 to 157.152.153.254157.152.153.255254
155157.152.154.0/24157.152.154.1 to 157.152.154.254157.152.154.255254
156157.152.155.0/24157.152.155.1 to 157.152.155.254157.152.155.255254
157157.152.156.0/24157.152.156.1 to 157.152.156.254157.152.156.255254
158157.152.157.0/24157.152.157.1 to 157.152.157.254157.152.157.255254
159157.152.158.0/24157.152.158.1 to 157.152.158.254157.152.158.255254
160157.152.159.0/24157.152.159.1 to 157.152.159.254157.152.159.255254
161157.152.160.0/24157.152.160.1 to 157.152.160.254157.152.160.255254
162157.152.161.0/24157.152.161.1 to 157.152.161.254157.152.161.255254
163157.152.162.0/24157.152.162.1 to 157.152.162.254157.152.162.255254
164157.152.163.0/24157.152.163.1 to 157.152.163.254157.152.163.255254
165157.152.164.0/24157.152.164.1 to 157.152.164.254157.152.164.255254
166157.152.165.0/24157.152.165.1 to 157.152.165.254157.152.165.255254
167157.152.166.0/24157.152.166.1 to 157.152.166.254157.152.166.255254
168157.152.167.0/24157.152.167.1 to 157.152.167.254157.152.167.255254
169157.152.168.0/24157.152.168.1 to 157.152.168.254157.152.168.255254
170157.152.169.0/24157.152.169.1 to 157.152.169.254157.152.169.255254
171157.152.170.0/24157.152.170.1 to 157.152.170.254157.152.170.255254
172157.152.171.0/24157.152.171.1 to 157.152.171.254157.152.171.255254
173157.152.172.0/24157.152.172.1 to 157.152.172.254157.152.172.255254
174157.152.173.0/24157.152.173.1 to 157.152.173.254157.152.173.255254
175157.152.174.0/24157.152.174.1 to 157.152.174.254157.152.174.255254
176157.152.175.0/24157.152.175.1 to 157.152.175.254157.152.175.255254
177157.152.176.0/24157.152.176.1 to 157.152.176.254157.152.176.255254
178157.152.177.0/24157.152.177.1 to 157.152.177.254157.152.177.255254
179157.152.178.0/24157.152.178.1 to 157.152.178.254157.152.178.255254
180157.152.179.0/24157.152.179.1 to 157.152.179.254157.152.179.255254
181157.152.180.0/24157.152.180.1 to 157.152.180.254157.152.180.255254
182157.152.181.0/24157.152.181.1 to 157.152.181.254157.152.181.255254
183157.152.182.0/24157.152.182.1 to 157.152.182.254157.152.182.255254
184157.152.183.0/24157.152.183.1 to 157.152.183.254157.152.183.255254
185157.152.184.0/24157.152.184.1 to 157.152.184.254157.152.184.255254
186157.152.185.0/24157.152.185.1 to 157.152.185.254157.152.185.255254
187157.152.186.0/24157.152.186.1 to 157.152.186.254157.152.186.255254
188157.152.187.0/24157.152.187.1 to 157.152.187.254157.152.187.255254
189157.152.188.0/24157.152.188.1 to 157.152.188.254157.152.188.255254
190157.152.189.0/24157.152.189.1 to 157.152.189.254157.152.189.255254
191157.152.190.0/24157.152.190.1 to 157.152.190.254157.152.190.255254
192157.152.191.0/24157.152.191.1 to 157.152.191.254157.152.191.255254
193157.152.192.0/24157.152.192.1 to 157.152.192.254157.152.192.255254
194157.152.193.0/24157.152.193.1 to 157.152.193.254157.152.193.255254
195157.152.194.0/24157.152.194.1 to 157.152.194.254157.152.194.255254
196157.152.195.0/24157.152.195.1 to 157.152.195.254157.152.195.255254
197157.152.196.0/24157.152.196.1 to 157.152.196.254157.152.196.255254
198157.152.197.0/24157.152.197.1 to 157.152.197.254157.152.197.255254
199157.152.198.0/24157.152.198.1 to 157.152.198.254157.152.198.255254
200157.152.199.0/24157.152.199.1 to 157.152.199.254157.152.199.255254
201157.152.200.0/24157.152.200.1 to 157.152.200.254157.152.200.255254
202157.152.201.0/24157.152.201.1 to 157.152.201.254157.152.201.255254
203157.152.202.0/24157.152.202.1 to 157.152.202.254157.152.202.255254
204157.152.203.0/24157.152.203.1 to 157.152.203.254157.152.203.255254
205157.152.204.0/24157.152.204.1 to 157.152.204.254157.152.204.255254
206157.152.205.0/24157.152.205.1 to 157.152.205.254157.152.205.255254
207157.152.206.0/24157.152.206.1 to 157.152.206.254157.152.206.255254
208157.152.207.0/24157.152.207.1 to 157.152.207.254157.152.207.255254
209157.152.208.0/24157.152.208.1 to 157.152.208.254157.152.208.255254
210157.152.209.0/24157.152.209.1 to 157.152.209.254157.152.209.255254
211157.152.210.0/24157.152.210.1 to 157.152.210.254157.152.210.255254
212157.152.211.0/24157.152.211.1 to 157.152.211.254157.152.211.255254
213157.152.212.0/24157.152.212.1 to 157.152.212.254157.152.212.255254
214157.152.213.0/24157.152.213.1 to 157.152.213.254157.152.213.255254
215157.152.214.0/24157.152.214.1 to 157.152.214.254157.152.214.255254
216157.152.215.0/24157.152.215.1 to 157.152.215.254157.152.215.255254
217157.152.216.0/24157.152.216.1 to 157.152.216.254157.152.216.255254
218157.152.217.0/24157.152.217.1 to 157.152.217.254157.152.217.255254
219157.152.218.0/24157.152.218.1 to 157.152.218.254157.152.218.255254
220157.152.219.0/24157.152.219.1 to 157.152.219.254157.152.219.255254
221157.152.220.0/24157.152.220.1 to 157.152.220.254157.152.220.255254
222157.152.221.0/24157.152.221.1 to 157.152.221.254157.152.221.255254
223157.152.222.0/24157.152.222.1 to 157.152.222.254157.152.222.255254
224157.152.223.0/24157.152.223.1 to 157.152.223.254157.152.223.255254
225157.152.224.0/24157.152.224.1 to 157.152.224.254157.152.224.255254
226157.152.225.0/24157.152.225.1 to 157.152.225.254157.152.225.255254
227157.152.226.0/24157.152.226.1 to 157.152.226.254157.152.226.255254
228157.152.227.0/24157.152.227.1 to 157.152.227.254157.152.227.255254
229157.152.228.0/24157.152.228.1 to 157.152.228.254157.152.228.255254
230157.152.229.0/24157.152.229.1 to 157.152.229.254157.152.229.255254
231157.152.230.0/24157.152.230.1 to 157.152.230.254157.152.230.255254
232157.152.231.0/24157.152.231.1 to 157.152.231.254157.152.231.255254
233157.152.232.0/24157.152.232.1 to 157.152.232.254157.152.232.255254
234157.152.233.0/24157.152.233.1 to 157.152.233.254157.152.233.255254
235157.152.234.0/24157.152.234.1 to 157.152.234.254157.152.234.255254
236157.152.235.0/24157.152.235.1 to 157.152.235.254157.152.235.255254
237157.152.236.0/24157.152.236.1 to 157.152.236.254157.152.236.255254
238157.152.237.0/24157.152.237.1 to 157.152.237.254157.152.237.255254
239157.152.238.0/24157.152.238.1 to 157.152.238.254157.152.238.255254
240157.152.239.0/24157.152.239.1 to 157.152.239.254157.152.239.255254
241157.152.240.0/24157.152.240.1 to 157.152.240.254157.152.240.255254
242157.152.241.0/24157.152.241.1 to 157.152.241.254157.152.241.255254
243157.152.242.0/24157.152.242.1 to 157.152.242.254157.152.242.255254
244157.152.243.0/24157.152.243.1 to 157.152.243.254157.152.243.255254
245157.152.244.0/24157.152.244.1 to 157.152.244.254157.152.244.255254
246157.152.245.0/24157.152.245.1 to 157.152.245.254157.152.245.255254
247157.152.246.0/24157.152.246.1 to 157.152.246.254157.152.246.255254
248157.152.247.0/24157.152.247.1 to 157.152.247.254157.152.247.255254
249157.152.248.0/24157.152.248.1 to 157.152.248.254157.152.248.255254
250157.152.249.0/24157.152.249.1 to 157.152.249.254157.152.249.255254
251157.152.250.0/24157.152.250.1 to 157.152.250.254157.152.250.255254
252157.152.251.0/24157.152.251.1 to 157.152.251.254157.152.251.255254
253157.152.252.0/24157.152.252.1 to 157.152.252.254157.152.252.255254
254157.152.253.0/24157.152.253.1 to 157.152.253.254157.152.253.255254
255157.152.254.0/24157.152.254.1 to 157.152.254.254157.152.254.255254
256157.152.255.0/24157.152.255.1 to 157.152.255.254157.152.255.255254

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.