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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.

Network154.48.0.0/13
Usable hosts524,286
Subnet mask255.248.0.0
Addresses524,288
Network address
154.48.0.0
Broadcast address
154.55.255.255
First usable
154.48.0.1
Last usable
154.55.255.254
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 9A300000 · Integer 2586836992 to 2587361279
Reverse DNS zones
48.154.in-addr.arpa
49.154.in-addr.arpa
50.154.in-addr.arpa
51.154.in-addr.arpa
52.154.in-addr.arpa
53.154.in-addr.arpa
54.154.in-addr.arpa
55.154.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
Address10011010.00110000.00000000.00000000154.48.0.0
Subnet mask11111111.11111000.00000000.00000000255.248.0.0
Network10011010.00110000.00000000.00000000154.48.0.0
Broadcast10011010.00110111.11111111.11111111154.55.255.255
Split into smaller subnets/23
/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)

154.48.0.0/13 makes 1,024 subnets of /23; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
1154.48.0.0/23154.48.0.1 to 154.48.1.254154.48.1.255510
2154.48.2.0/23154.48.2.1 to 154.48.3.254154.48.3.255510
3154.48.4.0/23154.48.4.1 to 154.48.5.254154.48.5.255510
4154.48.6.0/23154.48.6.1 to 154.48.7.254154.48.7.255510
5154.48.8.0/23154.48.8.1 to 154.48.9.254154.48.9.255510
6154.48.10.0/23154.48.10.1 to 154.48.11.254154.48.11.255510
7154.48.12.0/23154.48.12.1 to 154.48.13.254154.48.13.255510
8154.48.14.0/23154.48.14.1 to 154.48.15.254154.48.15.255510
9154.48.16.0/23154.48.16.1 to 154.48.17.254154.48.17.255510
10154.48.18.0/23154.48.18.1 to 154.48.19.254154.48.19.255510
11154.48.20.0/23154.48.20.1 to 154.48.21.254154.48.21.255510
12154.48.22.0/23154.48.22.1 to 154.48.23.254154.48.23.255510
13154.48.24.0/23154.48.24.1 to 154.48.25.254154.48.25.255510
14154.48.26.0/23154.48.26.1 to 154.48.27.254154.48.27.255510
15154.48.28.0/23154.48.28.1 to 154.48.29.254154.48.29.255510
16154.48.30.0/23154.48.30.1 to 154.48.31.254154.48.31.255510
17154.48.32.0/23154.48.32.1 to 154.48.33.254154.48.33.255510
18154.48.34.0/23154.48.34.1 to 154.48.35.254154.48.35.255510
19154.48.36.0/23154.48.36.1 to 154.48.37.254154.48.37.255510
20154.48.38.0/23154.48.38.1 to 154.48.39.254154.48.39.255510
21154.48.40.0/23154.48.40.1 to 154.48.41.254154.48.41.255510
22154.48.42.0/23154.48.42.1 to 154.48.43.254154.48.43.255510
23154.48.44.0/23154.48.44.1 to 154.48.45.254154.48.45.255510
24154.48.46.0/23154.48.46.1 to 154.48.47.254154.48.47.255510
25154.48.48.0/23154.48.48.1 to 154.48.49.254154.48.49.255510
26154.48.50.0/23154.48.50.1 to 154.48.51.254154.48.51.255510
27154.48.52.0/23154.48.52.1 to 154.48.53.254154.48.53.255510
28154.48.54.0/23154.48.54.1 to 154.48.55.254154.48.55.255510
29154.48.56.0/23154.48.56.1 to 154.48.57.254154.48.57.255510
30154.48.58.0/23154.48.58.1 to 154.48.59.254154.48.59.255510
31154.48.60.0/23154.48.60.1 to 154.48.61.254154.48.61.255510
32154.48.62.0/23154.48.62.1 to 154.48.63.254154.48.63.255510
33154.48.64.0/23154.48.64.1 to 154.48.65.254154.48.65.255510
34154.48.66.0/23154.48.66.1 to 154.48.67.254154.48.67.255510
35154.48.68.0/23154.48.68.1 to 154.48.69.254154.48.69.255510
36154.48.70.0/23154.48.70.1 to 154.48.71.254154.48.71.255510
37154.48.72.0/23154.48.72.1 to 154.48.73.254154.48.73.255510
38154.48.74.0/23154.48.74.1 to 154.48.75.254154.48.75.255510
39154.48.76.0/23154.48.76.1 to 154.48.77.254154.48.77.255510
40154.48.78.0/23154.48.78.1 to 154.48.79.254154.48.79.255510
41154.48.80.0/23154.48.80.1 to 154.48.81.254154.48.81.255510
42154.48.82.0/23154.48.82.1 to 154.48.83.254154.48.83.255510
43154.48.84.0/23154.48.84.1 to 154.48.85.254154.48.85.255510
44154.48.86.0/23154.48.86.1 to 154.48.87.254154.48.87.255510
45154.48.88.0/23154.48.88.1 to 154.48.89.254154.48.89.255510
46154.48.90.0/23154.48.90.1 to 154.48.91.254154.48.91.255510
47154.48.92.0/23154.48.92.1 to 154.48.93.254154.48.93.255510
48154.48.94.0/23154.48.94.1 to 154.48.95.254154.48.95.255510
49154.48.96.0/23154.48.96.1 to 154.48.97.254154.48.97.255510
50154.48.98.0/23154.48.98.1 to 154.48.99.254154.48.99.255510
51154.48.100.0/23154.48.100.1 to 154.48.101.254154.48.101.255510
52154.48.102.0/23154.48.102.1 to 154.48.103.254154.48.103.255510
53154.48.104.0/23154.48.104.1 to 154.48.105.254154.48.105.255510
54154.48.106.0/23154.48.106.1 to 154.48.107.254154.48.107.255510
55154.48.108.0/23154.48.108.1 to 154.48.109.254154.48.109.255510
56154.48.110.0/23154.48.110.1 to 154.48.111.254154.48.111.255510
57154.48.112.0/23154.48.112.1 to 154.48.113.254154.48.113.255510
58154.48.114.0/23154.48.114.1 to 154.48.115.254154.48.115.255510
59154.48.116.0/23154.48.116.1 to 154.48.117.254154.48.117.255510
60154.48.118.0/23154.48.118.1 to 154.48.119.254154.48.119.255510
61154.48.120.0/23154.48.120.1 to 154.48.121.254154.48.121.255510
62154.48.122.0/23154.48.122.1 to 154.48.123.254154.48.123.255510
63154.48.124.0/23154.48.124.1 to 154.48.125.254154.48.125.255510
64154.48.126.0/23154.48.126.1 to 154.48.127.254154.48.127.255510
65154.48.128.0/23154.48.128.1 to 154.48.129.254154.48.129.255510
66154.48.130.0/23154.48.130.1 to 154.48.131.254154.48.131.255510
67154.48.132.0/23154.48.132.1 to 154.48.133.254154.48.133.255510
68154.48.134.0/23154.48.134.1 to 154.48.135.254154.48.135.255510
69154.48.136.0/23154.48.136.1 to 154.48.137.254154.48.137.255510
70154.48.138.0/23154.48.138.1 to 154.48.139.254154.48.139.255510
71154.48.140.0/23154.48.140.1 to 154.48.141.254154.48.141.255510
72154.48.142.0/23154.48.142.1 to 154.48.143.254154.48.143.255510
73154.48.144.0/23154.48.144.1 to 154.48.145.254154.48.145.255510
74154.48.146.0/23154.48.146.1 to 154.48.147.254154.48.147.255510
75154.48.148.0/23154.48.148.1 to 154.48.149.254154.48.149.255510
76154.48.150.0/23154.48.150.1 to 154.48.151.254154.48.151.255510
77154.48.152.0/23154.48.152.1 to 154.48.153.254154.48.153.255510
78154.48.154.0/23154.48.154.1 to 154.48.155.254154.48.155.255510
79154.48.156.0/23154.48.156.1 to 154.48.157.254154.48.157.255510
80154.48.158.0/23154.48.158.1 to 154.48.159.254154.48.159.255510
81154.48.160.0/23154.48.160.1 to 154.48.161.254154.48.161.255510
82154.48.162.0/23154.48.162.1 to 154.48.163.254154.48.163.255510
83154.48.164.0/23154.48.164.1 to 154.48.165.254154.48.165.255510
84154.48.166.0/23154.48.166.1 to 154.48.167.254154.48.167.255510
85154.48.168.0/23154.48.168.1 to 154.48.169.254154.48.169.255510
86154.48.170.0/23154.48.170.1 to 154.48.171.254154.48.171.255510
87154.48.172.0/23154.48.172.1 to 154.48.173.254154.48.173.255510
88154.48.174.0/23154.48.174.1 to 154.48.175.254154.48.175.255510
89154.48.176.0/23154.48.176.1 to 154.48.177.254154.48.177.255510
90154.48.178.0/23154.48.178.1 to 154.48.179.254154.48.179.255510
91154.48.180.0/23154.48.180.1 to 154.48.181.254154.48.181.255510
92154.48.182.0/23154.48.182.1 to 154.48.183.254154.48.183.255510
93154.48.184.0/23154.48.184.1 to 154.48.185.254154.48.185.255510
94154.48.186.0/23154.48.186.1 to 154.48.187.254154.48.187.255510
95154.48.188.0/23154.48.188.1 to 154.48.189.254154.48.189.255510
96154.48.190.0/23154.48.190.1 to 154.48.191.254154.48.191.255510
97154.48.192.0/23154.48.192.1 to 154.48.193.254154.48.193.255510
98154.48.194.0/23154.48.194.1 to 154.48.195.254154.48.195.255510
99154.48.196.0/23154.48.196.1 to 154.48.197.254154.48.197.255510
100154.48.198.0/23154.48.198.1 to 154.48.199.254154.48.199.255510
101154.48.200.0/23154.48.200.1 to 154.48.201.254154.48.201.255510
102154.48.202.0/23154.48.202.1 to 154.48.203.254154.48.203.255510
103154.48.204.0/23154.48.204.1 to 154.48.205.254154.48.205.255510
104154.48.206.0/23154.48.206.1 to 154.48.207.254154.48.207.255510
105154.48.208.0/23154.48.208.1 to 154.48.209.254154.48.209.255510
106154.48.210.0/23154.48.210.1 to 154.48.211.254154.48.211.255510
107154.48.212.0/23154.48.212.1 to 154.48.213.254154.48.213.255510
108154.48.214.0/23154.48.214.1 to 154.48.215.254154.48.215.255510
109154.48.216.0/23154.48.216.1 to 154.48.217.254154.48.217.255510
110154.48.218.0/23154.48.218.1 to 154.48.219.254154.48.219.255510
111154.48.220.0/23154.48.220.1 to 154.48.221.254154.48.221.255510
112154.48.222.0/23154.48.222.1 to 154.48.223.254154.48.223.255510
113154.48.224.0/23154.48.224.1 to 154.48.225.254154.48.225.255510
114154.48.226.0/23154.48.226.1 to 154.48.227.254154.48.227.255510
115154.48.228.0/23154.48.228.1 to 154.48.229.254154.48.229.255510
116154.48.230.0/23154.48.230.1 to 154.48.231.254154.48.231.255510
117154.48.232.0/23154.48.232.1 to 154.48.233.254154.48.233.255510
118154.48.234.0/23154.48.234.1 to 154.48.235.254154.48.235.255510
119154.48.236.0/23154.48.236.1 to 154.48.237.254154.48.237.255510
120154.48.238.0/23154.48.238.1 to 154.48.239.254154.48.239.255510
121154.48.240.0/23154.48.240.1 to 154.48.241.254154.48.241.255510
122154.48.242.0/23154.48.242.1 to 154.48.243.254154.48.243.255510
123154.48.244.0/23154.48.244.1 to 154.48.245.254154.48.245.255510
124154.48.246.0/23154.48.246.1 to 154.48.247.254154.48.247.255510
125154.48.248.0/23154.48.248.1 to 154.48.249.254154.48.249.255510
126154.48.250.0/23154.48.250.1 to 154.48.251.254154.48.251.255510
127154.48.252.0/23154.48.252.1 to 154.48.253.254154.48.253.255510
128154.48.254.0/23154.48.254.1 to 154.48.255.254154.48.255.255510
129154.49.0.0/23154.49.0.1 to 154.49.1.254154.49.1.255510
130154.49.2.0/23154.49.2.1 to 154.49.3.254154.49.3.255510
131154.49.4.0/23154.49.4.1 to 154.49.5.254154.49.5.255510
132154.49.6.0/23154.49.6.1 to 154.49.7.254154.49.7.255510
133154.49.8.0/23154.49.8.1 to 154.49.9.254154.49.9.255510
134154.49.10.0/23154.49.10.1 to 154.49.11.254154.49.11.255510
135154.49.12.0/23154.49.12.1 to 154.49.13.254154.49.13.255510
136154.49.14.0/23154.49.14.1 to 154.49.15.254154.49.15.255510
137154.49.16.0/23154.49.16.1 to 154.49.17.254154.49.17.255510
138154.49.18.0/23154.49.18.1 to 154.49.19.254154.49.19.255510
139154.49.20.0/23154.49.20.1 to 154.49.21.254154.49.21.255510
140154.49.22.0/23154.49.22.1 to 154.49.23.254154.49.23.255510
141154.49.24.0/23154.49.24.1 to 154.49.25.254154.49.25.255510
142154.49.26.0/23154.49.26.1 to 154.49.27.254154.49.27.255510
143154.49.28.0/23154.49.28.1 to 154.49.29.254154.49.29.255510
144154.49.30.0/23154.49.30.1 to 154.49.31.254154.49.31.255510
145154.49.32.0/23154.49.32.1 to 154.49.33.254154.49.33.255510
146154.49.34.0/23154.49.34.1 to 154.49.35.254154.49.35.255510
147154.49.36.0/23154.49.36.1 to 154.49.37.254154.49.37.255510
148154.49.38.0/23154.49.38.1 to 154.49.39.254154.49.39.255510
149154.49.40.0/23154.49.40.1 to 154.49.41.254154.49.41.255510
150154.49.42.0/23154.49.42.1 to 154.49.43.254154.49.43.255510
151154.49.44.0/23154.49.44.1 to 154.49.45.254154.49.45.255510
152154.49.46.0/23154.49.46.1 to 154.49.47.254154.49.47.255510
153154.49.48.0/23154.49.48.1 to 154.49.49.254154.49.49.255510
154154.49.50.0/23154.49.50.1 to 154.49.51.254154.49.51.255510
155154.49.52.0/23154.49.52.1 to 154.49.53.254154.49.53.255510
156154.49.54.0/23154.49.54.1 to 154.49.55.254154.49.55.255510
157154.49.56.0/23154.49.56.1 to 154.49.57.254154.49.57.255510
158154.49.58.0/23154.49.58.1 to 154.49.59.254154.49.59.255510
159154.49.60.0/23154.49.60.1 to 154.49.61.254154.49.61.255510
160154.49.62.0/23154.49.62.1 to 154.49.63.254154.49.63.255510
161154.49.64.0/23154.49.64.1 to 154.49.65.254154.49.65.255510
162154.49.66.0/23154.49.66.1 to 154.49.67.254154.49.67.255510
163154.49.68.0/23154.49.68.1 to 154.49.69.254154.49.69.255510
164154.49.70.0/23154.49.70.1 to 154.49.71.254154.49.71.255510
165154.49.72.0/23154.49.72.1 to 154.49.73.254154.49.73.255510
166154.49.74.0/23154.49.74.1 to 154.49.75.254154.49.75.255510
167154.49.76.0/23154.49.76.1 to 154.49.77.254154.49.77.255510
168154.49.78.0/23154.49.78.1 to 154.49.79.254154.49.79.255510
169154.49.80.0/23154.49.80.1 to 154.49.81.254154.49.81.255510
170154.49.82.0/23154.49.82.1 to 154.49.83.254154.49.83.255510
171154.49.84.0/23154.49.84.1 to 154.49.85.254154.49.85.255510
172154.49.86.0/23154.49.86.1 to 154.49.87.254154.49.87.255510
173154.49.88.0/23154.49.88.1 to 154.49.89.254154.49.89.255510
174154.49.90.0/23154.49.90.1 to 154.49.91.254154.49.91.255510
175154.49.92.0/23154.49.92.1 to 154.49.93.254154.49.93.255510
176154.49.94.0/23154.49.94.1 to 154.49.95.254154.49.95.255510
177154.49.96.0/23154.49.96.1 to 154.49.97.254154.49.97.255510
178154.49.98.0/23154.49.98.1 to 154.49.99.254154.49.99.255510
179154.49.100.0/23154.49.100.1 to 154.49.101.254154.49.101.255510
180154.49.102.0/23154.49.102.1 to 154.49.103.254154.49.103.255510
181154.49.104.0/23154.49.104.1 to 154.49.105.254154.49.105.255510
182154.49.106.0/23154.49.106.1 to 154.49.107.254154.49.107.255510
183154.49.108.0/23154.49.108.1 to 154.49.109.254154.49.109.255510
184154.49.110.0/23154.49.110.1 to 154.49.111.254154.49.111.255510
185154.49.112.0/23154.49.112.1 to 154.49.113.254154.49.113.255510
186154.49.114.0/23154.49.114.1 to 154.49.115.254154.49.115.255510
187154.49.116.0/23154.49.116.1 to 154.49.117.254154.49.117.255510
188154.49.118.0/23154.49.118.1 to 154.49.119.254154.49.119.255510
189154.49.120.0/23154.49.120.1 to 154.49.121.254154.49.121.255510
190154.49.122.0/23154.49.122.1 to 154.49.123.254154.49.123.255510
191154.49.124.0/23154.49.124.1 to 154.49.125.254154.49.125.255510
192154.49.126.0/23154.49.126.1 to 154.49.127.254154.49.127.255510
193154.49.128.0/23154.49.128.1 to 154.49.129.254154.49.129.255510
194154.49.130.0/23154.49.130.1 to 154.49.131.254154.49.131.255510
195154.49.132.0/23154.49.132.1 to 154.49.133.254154.49.133.255510
196154.49.134.0/23154.49.134.1 to 154.49.135.254154.49.135.255510
197154.49.136.0/23154.49.136.1 to 154.49.137.254154.49.137.255510
198154.49.138.0/23154.49.138.1 to 154.49.139.254154.49.139.255510
199154.49.140.0/23154.49.140.1 to 154.49.141.254154.49.141.255510
200154.49.142.0/23154.49.142.1 to 154.49.143.254154.49.143.255510
201154.49.144.0/23154.49.144.1 to 154.49.145.254154.49.145.255510
202154.49.146.0/23154.49.146.1 to 154.49.147.254154.49.147.255510
203154.49.148.0/23154.49.148.1 to 154.49.149.254154.49.149.255510
204154.49.150.0/23154.49.150.1 to 154.49.151.254154.49.151.255510
205154.49.152.0/23154.49.152.1 to 154.49.153.254154.49.153.255510
206154.49.154.0/23154.49.154.1 to 154.49.155.254154.49.155.255510
207154.49.156.0/23154.49.156.1 to 154.49.157.254154.49.157.255510
208154.49.158.0/23154.49.158.1 to 154.49.159.254154.49.159.255510
209154.49.160.0/23154.49.160.1 to 154.49.161.254154.49.161.255510
210154.49.162.0/23154.49.162.1 to 154.49.163.254154.49.163.255510
211154.49.164.0/23154.49.164.1 to 154.49.165.254154.49.165.255510
212154.49.166.0/23154.49.166.1 to 154.49.167.254154.49.167.255510
213154.49.168.0/23154.49.168.1 to 154.49.169.254154.49.169.255510
214154.49.170.0/23154.49.170.1 to 154.49.171.254154.49.171.255510
215154.49.172.0/23154.49.172.1 to 154.49.173.254154.49.173.255510
216154.49.174.0/23154.49.174.1 to 154.49.175.254154.49.175.255510
217154.49.176.0/23154.49.176.1 to 154.49.177.254154.49.177.255510
218154.49.178.0/23154.49.178.1 to 154.49.179.254154.49.179.255510
219154.49.180.0/23154.49.180.1 to 154.49.181.254154.49.181.255510
220154.49.182.0/23154.49.182.1 to 154.49.183.254154.49.183.255510
221154.49.184.0/23154.49.184.1 to 154.49.185.254154.49.185.255510
222154.49.186.0/23154.49.186.1 to 154.49.187.254154.49.187.255510
223154.49.188.0/23154.49.188.1 to 154.49.189.254154.49.189.255510
224154.49.190.0/23154.49.190.1 to 154.49.191.254154.49.191.255510
225154.49.192.0/23154.49.192.1 to 154.49.193.254154.49.193.255510
226154.49.194.0/23154.49.194.1 to 154.49.195.254154.49.195.255510
227154.49.196.0/23154.49.196.1 to 154.49.197.254154.49.197.255510
228154.49.198.0/23154.49.198.1 to 154.49.199.254154.49.199.255510
229154.49.200.0/23154.49.200.1 to 154.49.201.254154.49.201.255510
230154.49.202.0/23154.49.202.1 to 154.49.203.254154.49.203.255510
231154.49.204.0/23154.49.204.1 to 154.49.205.254154.49.205.255510
232154.49.206.0/23154.49.206.1 to 154.49.207.254154.49.207.255510
233154.49.208.0/23154.49.208.1 to 154.49.209.254154.49.209.255510
234154.49.210.0/23154.49.210.1 to 154.49.211.254154.49.211.255510
235154.49.212.0/23154.49.212.1 to 154.49.213.254154.49.213.255510
236154.49.214.0/23154.49.214.1 to 154.49.215.254154.49.215.255510
237154.49.216.0/23154.49.216.1 to 154.49.217.254154.49.217.255510
238154.49.218.0/23154.49.218.1 to 154.49.219.254154.49.219.255510
239154.49.220.0/23154.49.220.1 to 154.49.221.254154.49.221.255510
240154.49.222.0/23154.49.222.1 to 154.49.223.254154.49.223.255510
241154.49.224.0/23154.49.224.1 to 154.49.225.254154.49.225.255510
242154.49.226.0/23154.49.226.1 to 154.49.227.254154.49.227.255510
243154.49.228.0/23154.49.228.1 to 154.49.229.254154.49.229.255510
244154.49.230.0/23154.49.230.1 to 154.49.231.254154.49.231.255510
245154.49.232.0/23154.49.232.1 to 154.49.233.254154.49.233.255510
246154.49.234.0/23154.49.234.1 to 154.49.235.254154.49.235.255510
247154.49.236.0/23154.49.236.1 to 154.49.237.254154.49.237.255510
248154.49.238.0/23154.49.238.1 to 154.49.239.254154.49.239.255510
249154.49.240.0/23154.49.240.1 to 154.49.241.254154.49.241.255510
250154.49.242.0/23154.49.242.1 to 154.49.243.254154.49.243.255510
251154.49.244.0/23154.49.244.1 to 154.49.245.254154.49.245.255510
252154.49.246.0/23154.49.246.1 to 154.49.247.254154.49.247.255510
253154.49.248.0/23154.49.248.1 to 154.49.249.254154.49.249.255510
254154.49.250.0/23154.49.250.1 to 154.49.251.254154.49.251.255510
255154.49.252.0/23154.49.252.1 to 154.49.253.254154.49.253.255510
256154.49.254.0/23154.49.254.1 to 154.49.255.254154.49.255.255510

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.