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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/22
/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 512 subnets of /22; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
1157.152.0.0/22157.152.0.1 to 157.152.3.254157.152.3.2551,022
2157.152.4.0/22157.152.4.1 to 157.152.7.254157.152.7.2551,022
3157.152.8.0/22157.152.8.1 to 157.152.11.254157.152.11.2551,022
4157.152.12.0/22157.152.12.1 to 157.152.15.254157.152.15.2551,022
5157.152.16.0/22157.152.16.1 to 157.152.19.254157.152.19.2551,022
6157.152.20.0/22157.152.20.1 to 157.152.23.254157.152.23.2551,022
7157.152.24.0/22157.152.24.1 to 157.152.27.254157.152.27.2551,022
8157.152.28.0/22157.152.28.1 to 157.152.31.254157.152.31.2551,022
9157.152.32.0/22157.152.32.1 to 157.152.35.254157.152.35.2551,022
10157.152.36.0/22157.152.36.1 to 157.152.39.254157.152.39.2551,022
11157.152.40.0/22157.152.40.1 to 157.152.43.254157.152.43.2551,022
12157.152.44.0/22157.152.44.1 to 157.152.47.254157.152.47.2551,022
13157.152.48.0/22157.152.48.1 to 157.152.51.254157.152.51.2551,022
14157.152.52.0/22157.152.52.1 to 157.152.55.254157.152.55.2551,022
15157.152.56.0/22157.152.56.1 to 157.152.59.254157.152.59.2551,022
16157.152.60.0/22157.152.60.1 to 157.152.63.254157.152.63.2551,022
17157.152.64.0/22157.152.64.1 to 157.152.67.254157.152.67.2551,022
18157.152.68.0/22157.152.68.1 to 157.152.71.254157.152.71.2551,022
19157.152.72.0/22157.152.72.1 to 157.152.75.254157.152.75.2551,022
20157.152.76.0/22157.152.76.1 to 157.152.79.254157.152.79.2551,022
21157.152.80.0/22157.152.80.1 to 157.152.83.254157.152.83.2551,022
22157.152.84.0/22157.152.84.1 to 157.152.87.254157.152.87.2551,022
23157.152.88.0/22157.152.88.1 to 157.152.91.254157.152.91.2551,022
24157.152.92.0/22157.152.92.1 to 157.152.95.254157.152.95.2551,022
25157.152.96.0/22157.152.96.1 to 157.152.99.254157.152.99.2551,022
26157.152.100.0/22157.152.100.1 to 157.152.103.254157.152.103.2551,022
27157.152.104.0/22157.152.104.1 to 157.152.107.254157.152.107.2551,022
28157.152.108.0/22157.152.108.1 to 157.152.111.254157.152.111.2551,022
29157.152.112.0/22157.152.112.1 to 157.152.115.254157.152.115.2551,022
30157.152.116.0/22157.152.116.1 to 157.152.119.254157.152.119.2551,022
31157.152.120.0/22157.152.120.1 to 157.152.123.254157.152.123.2551,022
32157.152.124.0/22157.152.124.1 to 157.152.127.254157.152.127.2551,022
33157.152.128.0/22157.152.128.1 to 157.152.131.254157.152.131.2551,022
34157.152.132.0/22157.152.132.1 to 157.152.135.254157.152.135.2551,022
35157.152.136.0/22157.152.136.1 to 157.152.139.254157.152.139.2551,022
36157.152.140.0/22157.152.140.1 to 157.152.143.254157.152.143.2551,022
37157.152.144.0/22157.152.144.1 to 157.152.147.254157.152.147.2551,022
38157.152.148.0/22157.152.148.1 to 157.152.151.254157.152.151.2551,022
39157.152.152.0/22157.152.152.1 to 157.152.155.254157.152.155.2551,022
40157.152.156.0/22157.152.156.1 to 157.152.159.254157.152.159.2551,022
41157.152.160.0/22157.152.160.1 to 157.152.163.254157.152.163.2551,022
42157.152.164.0/22157.152.164.1 to 157.152.167.254157.152.167.2551,022
43157.152.168.0/22157.152.168.1 to 157.152.171.254157.152.171.2551,022
44157.152.172.0/22157.152.172.1 to 157.152.175.254157.152.175.2551,022
45157.152.176.0/22157.152.176.1 to 157.152.179.254157.152.179.2551,022
46157.152.180.0/22157.152.180.1 to 157.152.183.254157.152.183.2551,022
47157.152.184.0/22157.152.184.1 to 157.152.187.254157.152.187.2551,022
48157.152.188.0/22157.152.188.1 to 157.152.191.254157.152.191.2551,022
49157.152.192.0/22157.152.192.1 to 157.152.195.254157.152.195.2551,022
50157.152.196.0/22157.152.196.1 to 157.152.199.254157.152.199.2551,022
51157.152.200.0/22157.152.200.1 to 157.152.203.254157.152.203.2551,022
52157.152.204.0/22157.152.204.1 to 157.152.207.254157.152.207.2551,022
53157.152.208.0/22157.152.208.1 to 157.152.211.254157.152.211.2551,022
54157.152.212.0/22157.152.212.1 to 157.152.215.254157.152.215.2551,022
55157.152.216.0/22157.152.216.1 to 157.152.219.254157.152.219.2551,022
56157.152.220.0/22157.152.220.1 to 157.152.223.254157.152.223.2551,022
57157.152.224.0/22157.152.224.1 to 157.152.227.254157.152.227.2551,022
58157.152.228.0/22157.152.228.1 to 157.152.231.254157.152.231.2551,022
59157.152.232.0/22157.152.232.1 to 157.152.235.254157.152.235.2551,022
60157.152.236.0/22157.152.236.1 to 157.152.239.254157.152.239.2551,022
61157.152.240.0/22157.152.240.1 to 157.152.243.254157.152.243.2551,022
62157.152.244.0/22157.152.244.1 to 157.152.247.254157.152.247.2551,022
63157.152.248.0/22157.152.248.1 to 157.152.251.254157.152.251.2551,022
64157.152.252.0/22157.152.252.1 to 157.152.255.254157.152.255.2551,022
65157.153.0.0/22157.153.0.1 to 157.153.3.254157.153.3.2551,022
66157.153.4.0/22157.153.4.1 to 157.153.7.254157.153.7.2551,022
67157.153.8.0/22157.153.8.1 to 157.153.11.254157.153.11.2551,022
68157.153.12.0/22157.153.12.1 to 157.153.15.254157.153.15.2551,022
69157.153.16.0/22157.153.16.1 to 157.153.19.254157.153.19.2551,022
70157.153.20.0/22157.153.20.1 to 157.153.23.254157.153.23.2551,022
71157.153.24.0/22157.153.24.1 to 157.153.27.254157.153.27.2551,022
72157.153.28.0/22157.153.28.1 to 157.153.31.254157.153.31.2551,022
73157.153.32.0/22157.153.32.1 to 157.153.35.254157.153.35.2551,022
74157.153.36.0/22157.153.36.1 to 157.153.39.254157.153.39.2551,022
75157.153.40.0/22157.153.40.1 to 157.153.43.254157.153.43.2551,022
76157.153.44.0/22157.153.44.1 to 157.153.47.254157.153.47.2551,022
77157.153.48.0/22157.153.48.1 to 157.153.51.254157.153.51.2551,022
78157.153.52.0/22157.153.52.1 to 157.153.55.254157.153.55.2551,022
79157.153.56.0/22157.153.56.1 to 157.153.59.254157.153.59.2551,022
80157.153.60.0/22157.153.60.1 to 157.153.63.254157.153.63.2551,022
81157.153.64.0/22157.153.64.1 to 157.153.67.254157.153.67.2551,022
82157.153.68.0/22157.153.68.1 to 157.153.71.254157.153.71.2551,022
83157.153.72.0/22157.153.72.1 to 157.153.75.254157.153.75.2551,022
84157.153.76.0/22157.153.76.1 to 157.153.79.254157.153.79.2551,022
85157.153.80.0/22157.153.80.1 to 157.153.83.254157.153.83.2551,022
86157.153.84.0/22157.153.84.1 to 157.153.87.254157.153.87.2551,022
87157.153.88.0/22157.153.88.1 to 157.153.91.254157.153.91.2551,022
88157.153.92.0/22157.153.92.1 to 157.153.95.254157.153.95.2551,022
89157.153.96.0/22157.153.96.1 to 157.153.99.254157.153.99.2551,022
90157.153.100.0/22157.153.100.1 to 157.153.103.254157.153.103.2551,022
91157.153.104.0/22157.153.104.1 to 157.153.107.254157.153.107.2551,022
92157.153.108.0/22157.153.108.1 to 157.153.111.254157.153.111.2551,022
93157.153.112.0/22157.153.112.1 to 157.153.115.254157.153.115.2551,022
94157.153.116.0/22157.153.116.1 to 157.153.119.254157.153.119.2551,022
95157.153.120.0/22157.153.120.1 to 157.153.123.254157.153.123.2551,022
96157.153.124.0/22157.153.124.1 to 157.153.127.254157.153.127.2551,022
97157.153.128.0/22157.153.128.1 to 157.153.131.254157.153.131.2551,022
98157.153.132.0/22157.153.132.1 to 157.153.135.254157.153.135.2551,022
99157.153.136.0/22157.153.136.1 to 157.153.139.254157.153.139.2551,022
100157.153.140.0/22157.153.140.1 to 157.153.143.254157.153.143.2551,022
101157.153.144.0/22157.153.144.1 to 157.153.147.254157.153.147.2551,022
102157.153.148.0/22157.153.148.1 to 157.153.151.254157.153.151.2551,022
103157.153.152.0/22157.153.152.1 to 157.153.155.254157.153.155.2551,022
104157.153.156.0/22157.153.156.1 to 157.153.159.254157.153.159.2551,022
105157.153.160.0/22157.153.160.1 to 157.153.163.254157.153.163.2551,022
106157.153.164.0/22157.153.164.1 to 157.153.167.254157.153.167.2551,022
107157.153.168.0/22157.153.168.1 to 157.153.171.254157.153.171.2551,022
108157.153.172.0/22157.153.172.1 to 157.153.175.254157.153.175.2551,022
109157.153.176.0/22157.153.176.1 to 157.153.179.254157.153.179.2551,022
110157.153.180.0/22157.153.180.1 to 157.153.183.254157.153.183.2551,022
111157.153.184.0/22157.153.184.1 to 157.153.187.254157.153.187.2551,022
112157.153.188.0/22157.153.188.1 to 157.153.191.254157.153.191.2551,022
113157.153.192.0/22157.153.192.1 to 157.153.195.254157.153.195.2551,022
114157.153.196.0/22157.153.196.1 to 157.153.199.254157.153.199.2551,022
115157.153.200.0/22157.153.200.1 to 157.153.203.254157.153.203.2551,022
116157.153.204.0/22157.153.204.1 to 157.153.207.254157.153.207.2551,022
117157.153.208.0/22157.153.208.1 to 157.153.211.254157.153.211.2551,022
118157.153.212.0/22157.153.212.1 to 157.153.215.254157.153.215.2551,022
119157.153.216.0/22157.153.216.1 to 157.153.219.254157.153.219.2551,022
120157.153.220.0/22157.153.220.1 to 157.153.223.254157.153.223.2551,022
121157.153.224.0/22157.153.224.1 to 157.153.227.254157.153.227.2551,022
122157.153.228.0/22157.153.228.1 to 157.153.231.254157.153.231.2551,022
123157.153.232.0/22157.153.232.1 to 157.153.235.254157.153.235.2551,022
124157.153.236.0/22157.153.236.1 to 157.153.239.254157.153.239.2551,022
125157.153.240.0/22157.153.240.1 to 157.153.243.254157.153.243.2551,022
126157.153.244.0/22157.153.244.1 to 157.153.247.254157.153.247.2551,022
127157.153.248.0/22157.153.248.1 to 157.153.251.254157.153.251.2551,022
128157.153.252.0/22157.153.252.1 to 157.153.255.254157.153.255.2551,022
129157.154.0.0/22157.154.0.1 to 157.154.3.254157.154.3.2551,022
130157.154.4.0/22157.154.4.1 to 157.154.7.254157.154.7.2551,022
131157.154.8.0/22157.154.8.1 to 157.154.11.254157.154.11.2551,022
132157.154.12.0/22157.154.12.1 to 157.154.15.254157.154.15.2551,022
133157.154.16.0/22157.154.16.1 to 157.154.19.254157.154.19.2551,022
134157.154.20.0/22157.154.20.1 to 157.154.23.254157.154.23.2551,022
135157.154.24.0/22157.154.24.1 to 157.154.27.254157.154.27.2551,022
136157.154.28.0/22157.154.28.1 to 157.154.31.254157.154.31.2551,022
137157.154.32.0/22157.154.32.1 to 157.154.35.254157.154.35.2551,022
138157.154.36.0/22157.154.36.1 to 157.154.39.254157.154.39.2551,022
139157.154.40.0/22157.154.40.1 to 157.154.43.254157.154.43.2551,022
140157.154.44.0/22157.154.44.1 to 157.154.47.254157.154.47.2551,022
141157.154.48.0/22157.154.48.1 to 157.154.51.254157.154.51.2551,022
142157.154.52.0/22157.154.52.1 to 157.154.55.254157.154.55.2551,022
143157.154.56.0/22157.154.56.1 to 157.154.59.254157.154.59.2551,022
144157.154.60.0/22157.154.60.1 to 157.154.63.254157.154.63.2551,022
145157.154.64.0/22157.154.64.1 to 157.154.67.254157.154.67.2551,022
146157.154.68.0/22157.154.68.1 to 157.154.71.254157.154.71.2551,022
147157.154.72.0/22157.154.72.1 to 157.154.75.254157.154.75.2551,022
148157.154.76.0/22157.154.76.1 to 157.154.79.254157.154.79.2551,022
149157.154.80.0/22157.154.80.1 to 157.154.83.254157.154.83.2551,022
150157.154.84.0/22157.154.84.1 to 157.154.87.254157.154.87.2551,022
151157.154.88.0/22157.154.88.1 to 157.154.91.254157.154.91.2551,022
152157.154.92.0/22157.154.92.1 to 157.154.95.254157.154.95.2551,022
153157.154.96.0/22157.154.96.1 to 157.154.99.254157.154.99.2551,022
154157.154.100.0/22157.154.100.1 to 157.154.103.254157.154.103.2551,022
155157.154.104.0/22157.154.104.1 to 157.154.107.254157.154.107.2551,022
156157.154.108.0/22157.154.108.1 to 157.154.111.254157.154.111.2551,022
157157.154.112.0/22157.154.112.1 to 157.154.115.254157.154.115.2551,022
158157.154.116.0/22157.154.116.1 to 157.154.119.254157.154.119.2551,022
159157.154.120.0/22157.154.120.1 to 157.154.123.254157.154.123.2551,022
160157.154.124.0/22157.154.124.1 to 157.154.127.254157.154.127.2551,022
161157.154.128.0/22157.154.128.1 to 157.154.131.254157.154.131.2551,022
162157.154.132.0/22157.154.132.1 to 157.154.135.254157.154.135.2551,022
163157.154.136.0/22157.154.136.1 to 157.154.139.254157.154.139.2551,022
164157.154.140.0/22157.154.140.1 to 157.154.143.254157.154.143.2551,022
165157.154.144.0/22157.154.144.1 to 157.154.147.254157.154.147.2551,022
166157.154.148.0/22157.154.148.1 to 157.154.151.254157.154.151.2551,022
167157.154.152.0/22157.154.152.1 to 157.154.155.254157.154.155.2551,022
168157.154.156.0/22157.154.156.1 to 157.154.159.254157.154.159.2551,022
169157.154.160.0/22157.154.160.1 to 157.154.163.254157.154.163.2551,022
170157.154.164.0/22157.154.164.1 to 157.154.167.254157.154.167.2551,022
171157.154.168.0/22157.154.168.1 to 157.154.171.254157.154.171.2551,022
172157.154.172.0/22157.154.172.1 to 157.154.175.254157.154.175.2551,022
173157.154.176.0/22157.154.176.1 to 157.154.179.254157.154.179.2551,022
174157.154.180.0/22157.154.180.1 to 157.154.183.254157.154.183.2551,022
175157.154.184.0/22157.154.184.1 to 157.154.187.254157.154.187.2551,022
176157.154.188.0/22157.154.188.1 to 157.154.191.254157.154.191.2551,022
177157.154.192.0/22157.154.192.1 to 157.154.195.254157.154.195.2551,022
178157.154.196.0/22157.154.196.1 to 157.154.199.254157.154.199.2551,022
179157.154.200.0/22157.154.200.1 to 157.154.203.254157.154.203.2551,022
180157.154.204.0/22157.154.204.1 to 157.154.207.254157.154.207.2551,022
181157.154.208.0/22157.154.208.1 to 157.154.211.254157.154.211.2551,022
182157.154.212.0/22157.154.212.1 to 157.154.215.254157.154.215.2551,022
183157.154.216.0/22157.154.216.1 to 157.154.219.254157.154.219.2551,022
184157.154.220.0/22157.154.220.1 to 157.154.223.254157.154.223.2551,022
185157.154.224.0/22157.154.224.1 to 157.154.227.254157.154.227.2551,022
186157.154.228.0/22157.154.228.1 to 157.154.231.254157.154.231.2551,022
187157.154.232.0/22157.154.232.1 to 157.154.235.254157.154.235.2551,022
188157.154.236.0/22157.154.236.1 to 157.154.239.254157.154.239.2551,022
189157.154.240.0/22157.154.240.1 to 157.154.243.254157.154.243.2551,022
190157.154.244.0/22157.154.244.1 to 157.154.247.254157.154.247.2551,022
191157.154.248.0/22157.154.248.1 to 157.154.251.254157.154.251.2551,022
192157.154.252.0/22157.154.252.1 to 157.154.255.254157.154.255.2551,022
193157.155.0.0/22157.155.0.1 to 157.155.3.254157.155.3.2551,022
194157.155.4.0/22157.155.4.1 to 157.155.7.254157.155.7.2551,022
195157.155.8.0/22157.155.8.1 to 157.155.11.254157.155.11.2551,022
196157.155.12.0/22157.155.12.1 to 157.155.15.254157.155.15.2551,022
197157.155.16.0/22157.155.16.1 to 157.155.19.254157.155.19.2551,022
198157.155.20.0/22157.155.20.1 to 157.155.23.254157.155.23.2551,022
199157.155.24.0/22157.155.24.1 to 157.155.27.254157.155.27.2551,022
200157.155.28.0/22157.155.28.1 to 157.155.31.254157.155.31.2551,022
201157.155.32.0/22157.155.32.1 to 157.155.35.254157.155.35.2551,022
202157.155.36.0/22157.155.36.1 to 157.155.39.254157.155.39.2551,022
203157.155.40.0/22157.155.40.1 to 157.155.43.254157.155.43.2551,022
204157.155.44.0/22157.155.44.1 to 157.155.47.254157.155.47.2551,022
205157.155.48.0/22157.155.48.1 to 157.155.51.254157.155.51.2551,022
206157.155.52.0/22157.155.52.1 to 157.155.55.254157.155.55.2551,022
207157.155.56.0/22157.155.56.1 to 157.155.59.254157.155.59.2551,022
208157.155.60.0/22157.155.60.1 to 157.155.63.254157.155.63.2551,022
209157.155.64.0/22157.155.64.1 to 157.155.67.254157.155.67.2551,022
210157.155.68.0/22157.155.68.1 to 157.155.71.254157.155.71.2551,022
211157.155.72.0/22157.155.72.1 to 157.155.75.254157.155.75.2551,022
212157.155.76.0/22157.155.76.1 to 157.155.79.254157.155.79.2551,022
213157.155.80.0/22157.155.80.1 to 157.155.83.254157.155.83.2551,022
214157.155.84.0/22157.155.84.1 to 157.155.87.254157.155.87.2551,022
215157.155.88.0/22157.155.88.1 to 157.155.91.254157.155.91.2551,022
216157.155.92.0/22157.155.92.1 to 157.155.95.254157.155.95.2551,022
217157.155.96.0/22157.155.96.1 to 157.155.99.254157.155.99.2551,022
218157.155.100.0/22157.155.100.1 to 157.155.103.254157.155.103.2551,022
219157.155.104.0/22157.155.104.1 to 157.155.107.254157.155.107.2551,022
220157.155.108.0/22157.155.108.1 to 157.155.111.254157.155.111.2551,022
221157.155.112.0/22157.155.112.1 to 157.155.115.254157.155.115.2551,022
222157.155.116.0/22157.155.116.1 to 157.155.119.254157.155.119.2551,022
223157.155.120.0/22157.155.120.1 to 157.155.123.254157.155.123.2551,022
224157.155.124.0/22157.155.124.1 to 157.155.127.254157.155.127.2551,022
225157.155.128.0/22157.155.128.1 to 157.155.131.254157.155.131.2551,022
226157.155.132.0/22157.155.132.1 to 157.155.135.254157.155.135.2551,022
227157.155.136.0/22157.155.136.1 to 157.155.139.254157.155.139.2551,022
228157.155.140.0/22157.155.140.1 to 157.155.143.254157.155.143.2551,022
229157.155.144.0/22157.155.144.1 to 157.155.147.254157.155.147.2551,022
230157.155.148.0/22157.155.148.1 to 157.155.151.254157.155.151.2551,022
231157.155.152.0/22157.155.152.1 to 157.155.155.254157.155.155.2551,022
232157.155.156.0/22157.155.156.1 to 157.155.159.254157.155.159.2551,022
233157.155.160.0/22157.155.160.1 to 157.155.163.254157.155.163.2551,022
234157.155.164.0/22157.155.164.1 to 157.155.167.254157.155.167.2551,022
235157.155.168.0/22157.155.168.1 to 157.155.171.254157.155.171.2551,022
236157.155.172.0/22157.155.172.1 to 157.155.175.254157.155.175.2551,022
237157.155.176.0/22157.155.176.1 to 157.155.179.254157.155.179.2551,022
238157.155.180.0/22157.155.180.1 to 157.155.183.254157.155.183.2551,022
239157.155.184.0/22157.155.184.1 to 157.155.187.254157.155.187.2551,022
240157.155.188.0/22157.155.188.1 to 157.155.191.254157.155.191.2551,022
241157.155.192.0/22157.155.192.1 to 157.155.195.254157.155.195.2551,022
242157.155.196.0/22157.155.196.1 to 157.155.199.254157.155.199.2551,022
243157.155.200.0/22157.155.200.1 to 157.155.203.254157.155.203.2551,022
244157.155.204.0/22157.155.204.1 to 157.155.207.254157.155.207.2551,022
245157.155.208.0/22157.155.208.1 to 157.155.211.254157.155.211.2551,022
246157.155.212.0/22157.155.212.1 to 157.155.215.254157.155.215.2551,022
247157.155.216.0/22157.155.216.1 to 157.155.219.254157.155.219.2551,022
248157.155.220.0/22157.155.220.1 to 157.155.223.254157.155.223.2551,022
249157.155.224.0/22157.155.224.1 to 157.155.227.254157.155.227.2551,022
250157.155.228.0/22157.155.228.1 to 157.155.231.254157.155.231.2551,022
251157.155.232.0/22157.155.232.1 to 157.155.235.254157.155.235.2551,022
252157.155.236.0/22157.155.236.1 to 157.155.239.254157.155.239.2551,022
253157.155.240.0/22157.155.240.1 to 157.155.243.254157.155.243.2551,022
254157.155.244.0/22157.155.244.1 to 157.155.247.254157.155.247.2551,022
255157.155.248.0/22157.155.248.1 to 157.155.251.254157.155.251.2551,022
256157.155.252.0/22157.155.252.1 to 157.155.255.254157.155.255.2551,022

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.