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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.

Network149.0.0.0/14
Usable hosts262,142
Subnet mask255.252.0.0
Addresses262,144
Network address
149.0.0.0
Broadcast address
149.3.255.255
First usable
149.0.0.1
Last usable
149.3.255.254
Usable hosts
262,142 (262,144 less the network and broadcast addresses)
Subnet mask
255.252.0.0
Wildcard mask
0.3.255.255 (Cisco ACLs, OSPF)
Prefix length
/14
Type
Public public
Old class
B (default /16)
As numbers
Hex 95000000 · Integer 2499805184 to 2500067327
Reverse DNS zones
0.149.in-addr.arpa
1.149.in-addr.arpa
2.149.in-addr.arpa
3.149.in-addr.arpa
/14 is not on a 8-bit boundary, so it takes 4 /16 zones.
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address10010101.00000000.00000000.00000000149.0.0.0
Subnet mask11111111.11111100.00000000.00000000255.252.0.0
Network10010101.00000000.00000000.00000000149.0.0.0
Broadcast10010101.00000011.11111111.11111111149.3.255.255
Split into smaller subnets/23
/15 (2)/16 (4)/17 (8)/18 (16)/19 (32)/20 (64)/21 (128)/22 (256)/23 (512)/24 (1,024)/25 (2,048)/26 (4,096)

149.0.0.0/14 makes 512 subnets of /23; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
1149.0.0.0/23149.0.0.1 to 149.0.1.254149.0.1.255510
2149.0.2.0/23149.0.2.1 to 149.0.3.254149.0.3.255510
3149.0.4.0/23149.0.4.1 to 149.0.5.254149.0.5.255510
4149.0.6.0/23149.0.6.1 to 149.0.7.254149.0.7.255510
5149.0.8.0/23149.0.8.1 to 149.0.9.254149.0.9.255510
6149.0.10.0/23149.0.10.1 to 149.0.11.254149.0.11.255510
7149.0.12.0/23149.0.12.1 to 149.0.13.254149.0.13.255510
8149.0.14.0/23149.0.14.1 to 149.0.15.254149.0.15.255510
9149.0.16.0/23149.0.16.1 to 149.0.17.254149.0.17.255510
10149.0.18.0/23149.0.18.1 to 149.0.19.254149.0.19.255510
11149.0.20.0/23149.0.20.1 to 149.0.21.254149.0.21.255510
12149.0.22.0/23149.0.22.1 to 149.0.23.254149.0.23.255510
13149.0.24.0/23149.0.24.1 to 149.0.25.254149.0.25.255510
14149.0.26.0/23149.0.26.1 to 149.0.27.254149.0.27.255510
15149.0.28.0/23149.0.28.1 to 149.0.29.254149.0.29.255510
16149.0.30.0/23149.0.30.1 to 149.0.31.254149.0.31.255510
17149.0.32.0/23149.0.32.1 to 149.0.33.254149.0.33.255510
18149.0.34.0/23149.0.34.1 to 149.0.35.254149.0.35.255510
19149.0.36.0/23149.0.36.1 to 149.0.37.254149.0.37.255510
20149.0.38.0/23149.0.38.1 to 149.0.39.254149.0.39.255510
21149.0.40.0/23149.0.40.1 to 149.0.41.254149.0.41.255510
22149.0.42.0/23149.0.42.1 to 149.0.43.254149.0.43.255510
23149.0.44.0/23149.0.44.1 to 149.0.45.254149.0.45.255510
24149.0.46.0/23149.0.46.1 to 149.0.47.254149.0.47.255510
25149.0.48.0/23149.0.48.1 to 149.0.49.254149.0.49.255510
26149.0.50.0/23149.0.50.1 to 149.0.51.254149.0.51.255510
27149.0.52.0/23149.0.52.1 to 149.0.53.254149.0.53.255510
28149.0.54.0/23149.0.54.1 to 149.0.55.254149.0.55.255510
29149.0.56.0/23149.0.56.1 to 149.0.57.254149.0.57.255510
30149.0.58.0/23149.0.58.1 to 149.0.59.254149.0.59.255510
31149.0.60.0/23149.0.60.1 to 149.0.61.254149.0.61.255510
32149.0.62.0/23149.0.62.1 to 149.0.63.254149.0.63.255510
33149.0.64.0/23149.0.64.1 to 149.0.65.254149.0.65.255510
34149.0.66.0/23149.0.66.1 to 149.0.67.254149.0.67.255510
35149.0.68.0/23149.0.68.1 to 149.0.69.254149.0.69.255510
36149.0.70.0/23149.0.70.1 to 149.0.71.254149.0.71.255510
37149.0.72.0/23149.0.72.1 to 149.0.73.254149.0.73.255510
38149.0.74.0/23149.0.74.1 to 149.0.75.254149.0.75.255510
39149.0.76.0/23149.0.76.1 to 149.0.77.254149.0.77.255510
40149.0.78.0/23149.0.78.1 to 149.0.79.254149.0.79.255510
41149.0.80.0/23149.0.80.1 to 149.0.81.254149.0.81.255510
42149.0.82.0/23149.0.82.1 to 149.0.83.254149.0.83.255510
43149.0.84.0/23149.0.84.1 to 149.0.85.254149.0.85.255510
44149.0.86.0/23149.0.86.1 to 149.0.87.254149.0.87.255510
45149.0.88.0/23149.0.88.1 to 149.0.89.254149.0.89.255510
46149.0.90.0/23149.0.90.1 to 149.0.91.254149.0.91.255510
47149.0.92.0/23149.0.92.1 to 149.0.93.254149.0.93.255510
48149.0.94.0/23149.0.94.1 to 149.0.95.254149.0.95.255510
49149.0.96.0/23149.0.96.1 to 149.0.97.254149.0.97.255510
50149.0.98.0/23149.0.98.1 to 149.0.99.254149.0.99.255510
51149.0.100.0/23149.0.100.1 to 149.0.101.254149.0.101.255510
52149.0.102.0/23149.0.102.1 to 149.0.103.254149.0.103.255510
53149.0.104.0/23149.0.104.1 to 149.0.105.254149.0.105.255510
54149.0.106.0/23149.0.106.1 to 149.0.107.254149.0.107.255510
55149.0.108.0/23149.0.108.1 to 149.0.109.254149.0.109.255510
56149.0.110.0/23149.0.110.1 to 149.0.111.254149.0.111.255510
57149.0.112.0/23149.0.112.1 to 149.0.113.254149.0.113.255510
58149.0.114.0/23149.0.114.1 to 149.0.115.254149.0.115.255510
59149.0.116.0/23149.0.116.1 to 149.0.117.254149.0.117.255510
60149.0.118.0/23149.0.118.1 to 149.0.119.254149.0.119.255510
61149.0.120.0/23149.0.120.1 to 149.0.121.254149.0.121.255510
62149.0.122.0/23149.0.122.1 to 149.0.123.254149.0.123.255510
63149.0.124.0/23149.0.124.1 to 149.0.125.254149.0.125.255510
64149.0.126.0/23149.0.126.1 to 149.0.127.254149.0.127.255510
65149.0.128.0/23149.0.128.1 to 149.0.129.254149.0.129.255510
66149.0.130.0/23149.0.130.1 to 149.0.131.254149.0.131.255510
67149.0.132.0/23149.0.132.1 to 149.0.133.254149.0.133.255510
68149.0.134.0/23149.0.134.1 to 149.0.135.254149.0.135.255510
69149.0.136.0/23149.0.136.1 to 149.0.137.254149.0.137.255510
70149.0.138.0/23149.0.138.1 to 149.0.139.254149.0.139.255510
71149.0.140.0/23149.0.140.1 to 149.0.141.254149.0.141.255510
72149.0.142.0/23149.0.142.1 to 149.0.143.254149.0.143.255510
73149.0.144.0/23149.0.144.1 to 149.0.145.254149.0.145.255510
74149.0.146.0/23149.0.146.1 to 149.0.147.254149.0.147.255510
75149.0.148.0/23149.0.148.1 to 149.0.149.254149.0.149.255510
76149.0.150.0/23149.0.150.1 to 149.0.151.254149.0.151.255510
77149.0.152.0/23149.0.152.1 to 149.0.153.254149.0.153.255510
78149.0.154.0/23149.0.154.1 to 149.0.155.254149.0.155.255510
79149.0.156.0/23149.0.156.1 to 149.0.157.254149.0.157.255510
80149.0.158.0/23149.0.158.1 to 149.0.159.254149.0.159.255510
81149.0.160.0/23149.0.160.1 to 149.0.161.254149.0.161.255510
82149.0.162.0/23149.0.162.1 to 149.0.163.254149.0.163.255510
83149.0.164.0/23149.0.164.1 to 149.0.165.254149.0.165.255510
84149.0.166.0/23149.0.166.1 to 149.0.167.254149.0.167.255510
85149.0.168.0/23149.0.168.1 to 149.0.169.254149.0.169.255510
86149.0.170.0/23149.0.170.1 to 149.0.171.254149.0.171.255510
87149.0.172.0/23149.0.172.1 to 149.0.173.254149.0.173.255510
88149.0.174.0/23149.0.174.1 to 149.0.175.254149.0.175.255510
89149.0.176.0/23149.0.176.1 to 149.0.177.254149.0.177.255510
90149.0.178.0/23149.0.178.1 to 149.0.179.254149.0.179.255510
91149.0.180.0/23149.0.180.1 to 149.0.181.254149.0.181.255510
92149.0.182.0/23149.0.182.1 to 149.0.183.254149.0.183.255510
93149.0.184.0/23149.0.184.1 to 149.0.185.254149.0.185.255510
94149.0.186.0/23149.0.186.1 to 149.0.187.254149.0.187.255510
95149.0.188.0/23149.0.188.1 to 149.0.189.254149.0.189.255510
96149.0.190.0/23149.0.190.1 to 149.0.191.254149.0.191.255510
97149.0.192.0/23149.0.192.1 to 149.0.193.254149.0.193.255510
98149.0.194.0/23149.0.194.1 to 149.0.195.254149.0.195.255510
99149.0.196.0/23149.0.196.1 to 149.0.197.254149.0.197.255510
100149.0.198.0/23149.0.198.1 to 149.0.199.254149.0.199.255510
101149.0.200.0/23149.0.200.1 to 149.0.201.254149.0.201.255510
102149.0.202.0/23149.0.202.1 to 149.0.203.254149.0.203.255510
103149.0.204.0/23149.0.204.1 to 149.0.205.254149.0.205.255510
104149.0.206.0/23149.0.206.1 to 149.0.207.254149.0.207.255510
105149.0.208.0/23149.0.208.1 to 149.0.209.254149.0.209.255510
106149.0.210.0/23149.0.210.1 to 149.0.211.254149.0.211.255510
107149.0.212.0/23149.0.212.1 to 149.0.213.254149.0.213.255510
108149.0.214.0/23149.0.214.1 to 149.0.215.254149.0.215.255510
109149.0.216.0/23149.0.216.1 to 149.0.217.254149.0.217.255510
110149.0.218.0/23149.0.218.1 to 149.0.219.254149.0.219.255510
111149.0.220.0/23149.0.220.1 to 149.0.221.254149.0.221.255510
112149.0.222.0/23149.0.222.1 to 149.0.223.254149.0.223.255510
113149.0.224.0/23149.0.224.1 to 149.0.225.254149.0.225.255510
114149.0.226.0/23149.0.226.1 to 149.0.227.254149.0.227.255510
115149.0.228.0/23149.0.228.1 to 149.0.229.254149.0.229.255510
116149.0.230.0/23149.0.230.1 to 149.0.231.254149.0.231.255510
117149.0.232.0/23149.0.232.1 to 149.0.233.254149.0.233.255510
118149.0.234.0/23149.0.234.1 to 149.0.235.254149.0.235.255510
119149.0.236.0/23149.0.236.1 to 149.0.237.254149.0.237.255510
120149.0.238.0/23149.0.238.1 to 149.0.239.254149.0.239.255510
121149.0.240.0/23149.0.240.1 to 149.0.241.254149.0.241.255510
122149.0.242.0/23149.0.242.1 to 149.0.243.254149.0.243.255510
123149.0.244.0/23149.0.244.1 to 149.0.245.254149.0.245.255510
124149.0.246.0/23149.0.246.1 to 149.0.247.254149.0.247.255510
125149.0.248.0/23149.0.248.1 to 149.0.249.254149.0.249.255510
126149.0.250.0/23149.0.250.1 to 149.0.251.254149.0.251.255510
127149.0.252.0/23149.0.252.1 to 149.0.253.254149.0.253.255510
128149.0.254.0/23149.0.254.1 to 149.0.255.254149.0.255.255510
129149.1.0.0/23149.1.0.1 to 149.1.1.254149.1.1.255510
130149.1.2.0/23149.1.2.1 to 149.1.3.254149.1.3.255510
131149.1.4.0/23149.1.4.1 to 149.1.5.254149.1.5.255510
132149.1.6.0/23149.1.6.1 to 149.1.7.254149.1.7.255510
133149.1.8.0/23149.1.8.1 to 149.1.9.254149.1.9.255510
134149.1.10.0/23149.1.10.1 to 149.1.11.254149.1.11.255510
135149.1.12.0/23149.1.12.1 to 149.1.13.254149.1.13.255510
136149.1.14.0/23149.1.14.1 to 149.1.15.254149.1.15.255510
137149.1.16.0/23149.1.16.1 to 149.1.17.254149.1.17.255510
138149.1.18.0/23149.1.18.1 to 149.1.19.254149.1.19.255510
139149.1.20.0/23149.1.20.1 to 149.1.21.254149.1.21.255510
140149.1.22.0/23149.1.22.1 to 149.1.23.254149.1.23.255510
141149.1.24.0/23149.1.24.1 to 149.1.25.254149.1.25.255510
142149.1.26.0/23149.1.26.1 to 149.1.27.254149.1.27.255510
143149.1.28.0/23149.1.28.1 to 149.1.29.254149.1.29.255510
144149.1.30.0/23149.1.30.1 to 149.1.31.254149.1.31.255510
145149.1.32.0/23149.1.32.1 to 149.1.33.254149.1.33.255510
146149.1.34.0/23149.1.34.1 to 149.1.35.254149.1.35.255510
147149.1.36.0/23149.1.36.1 to 149.1.37.254149.1.37.255510
148149.1.38.0/23149.1.38.1 to 149.1.39.254149.1.39.255510
149149.1.40.0/23149.1.40.1 to 149.1.41.254149.1.41.255510
150149.1.42.0/23149.1.42.1 to 149.1.43.254149.1.43.255510
151149.1.44.0/23149.1.44.1 to 149.1.45.254149.1.45.255510
152149.1.46.0/23149.1.46.1 to 149.1.47.254149.1.47.255510
153149.1.48.0/23149.1.48.1 to 149.1.49.254149.1.49.255510
154149.1.50.0/23149.1.50.1 to 149.1.51.254149.1.51.255510
155149.1.52.0/23149.1.52.1 to 149.1.53.254149.1.53.255510
156149.1.54.0/23149.1.54.1 to 149.1.55.254149.1.55.255510
157149.1.56.0/23149.1.56.1 to 149.1.57.254149.1.57.255510
158149.1.58.0/23149.1.58.1 to 149.1.59.254149.1.59.255510
159149.1.60.0/23149.1.60.1 to 149.1.61.254149.1.61.255510
160149.1.62.0/23149.1.62.1 to 149.1.63.254149.1.63.255510
161149.1.64.0/23149.1.64.1 to 149.1.65.254149.1.65.255510
162149.1.66.0/23149.1.66.1 to 149.1.67.254149.1.67.255510
163149.1.68.0/23149.1.68.1 to 149.1.69.254149.1.69.255510
164149.1.70.0/23149.1.70.1 to 149.1.71.254149.1.71.255510
165149.1.72.0/23149.1.72.1 to 149.1.73.254149.1.73.255510
166149.1.74.0/23149.1.74.1 to 149.1.75.254149.1.75.255510
167149.1.76.0/23149.1.76.1 to 149.1.77.254149.1.77.255510
168149.1.78.0/23149.1.78.1 to 149.1.79.254149.1.79.255510
169149.1.80.0/23149.1.80.1 to 149.1.81.254149.1.81.255510
170149.1.82.0/23149.1.82.1 to 149.1.83.254149.1.83.255510
171149.1.84.0/23149.1.84.1 to 149.1.85.254149.1.85.255510
172149.1.86.0/23149.1.86.1 to 149.1.87.254149.1.87.255510
173149.1.88.0/23149.1.88.1 to 149.1.89.254149.1.89.255510
174149.1.90.0/23149.1.90.1 to 149.1.91.254149.1.91.255510
175149.1.92.0/23149.1.92.1 to 149.1.93.254149.1.93.255510
176149.1.94.0/23149.1.94.1 to 149.1.95.254149.1.95.255510
177149.1.96.0/23149.1.96.1 to 149.1.97.254149.1.97.255510
178149.1.98.0/23149.1.98.1 to 149.1.99.254149.1.99.255510
179149.1.100.0/23149.1.100.1 to 149.1.101.254149.1.101.255510
180149.1.102.0/23149.1.102.1 to 149.1.103.254149.1.103.255510
181149.1.104.0/23149.1.104.1 to 149.1.105.254149.1.105.255510
182149.1.106.0/23149.1.106.1 to 149.1.107.254149.1.107.255510
183149.1.108.0/23149.1.108.1 to 149.1.109.254149.1.109.255510
184149.1.110.0/23149.1.110.1 to 149.1.111.254149.1.111.255510
185149.1.112.0/23149.1.112.1 to 149.1.113.254149.1.113.255510
186149.1.114.0/23149.1.114.1 to 149.1.115.254149.1.115.255510
187149.1.116.0/23149.1.116.1 to 149.1.117.254149.1.117.255510
188149.1.118.0/23149.1.118.1 to 149.1.119.254149.1.119.255510
189149.1.120.0/23149.1.120.1 to 149.1.121.254149.1.121.255510
190149.1.122.0/23149.1.122.1 to 149.1.123.254149.1.123.255510
191149.1.124.0/23149.1.124.1 to 149.1.125.254149.1.125.255510
192149.1.126.0/23149.1.126.1 to 149.1.127.254149.1.127.255510
193149.1.128.0/23149.1.128.1 to 149.1.129.254149.1.129.255510
194149.1.130.0/23149.1.130.1 to 149.1.131.254149.1.131.255510
195149.1.132.0/23149.1.132.1 to 149.1.133.254149.1.133.255510
196149.1.134.0/23149.1.134.1 to 149.1.135.254149.1.135.255510
197149.1.136.0/23149.1.136.1 to 149.1.137.254149.1.137.255510
198149.1.138.0/23149.1.138.1 to 149.1.139.254149.1.139.255510
199149.1.140.0/23149.1.140.1 to 149.1.141.254149.1.141.255510
200149.1.142.0/23149.1.142.1 to 149.1.143.254149.1.143.255510
201149.1.144.0/23149.1.144.1 to 149.1.145.254149.1.145.255510
202149.1.146.0/23149.1.146.1 to 149.1.147.254149.1.147.255510
203149.1.148.0/23149.1.148.1 to 149.1.149.254149.1.149.255510
204149.1.150.0/23149.1.150.1 to 149.1.151.254149.1.151.255510
205149.1.152.0/23149.1.152.1 to 149.1.153.254149.1.153.255510
206149.1.154.0/23149.1.154.1 to 149.1.155.254149.1.155.255510
207149.1.156.0/23149.1.156.1 to 149.1.157.254149.1.157.255510
208149.1.158.0/23149.1.158.1 to 149.1.159.254149.1.159.255510
209149.1.160.0/23149.1.160.1 to 149.1.161.254149.1.161.255510
210149.1.162.0/23149.1.162.1 to 149.1.163.254149.1.163.255510
211149.1.164.0/23149.1.164.1 to 149.1.165.254149.1.165.255510
212149.1.166.0/23149.1.166.1 to 149.1.167.254149.1.167.255510
213149.1.168.0/23149.1.168.1 to 149.1.169.254149.1.169.255510
214149.1.170.0/23149.1.170.1 to 149.1.171.254149.1.171.255510
215149.1.172.0/23149.1.172.1 to 149.1.173.254149.1.173.255510
216149.1.174.0/23149.1.174.1 to 149.1.175.254149.1.175.255510
217149.1.176.0/23149.1.176.1 to 149.1.177.254149.1.177.255510
218149.1.178.0/23149.1.178.1 to 149.1.179.254149.1.179.255510
219149.1.180.0/23149.1.180.1 to 149.1.181.254149.1.181.255510
220149.1.182.0/23149.1.182.1 to 149.1.183.254149.1.183.255510
221149.1.184.0/23149.1.184.1 to 149.1.185.254149.1.185.255510
222149.1.186.0/23149.1.186.1 to 149.1.187.254149.1.187.255510
223149.1.188.0/23149.1.188.1 to 149.1.189.254149.1.189.255510
224149.1.190.0/23149.1.190.1 to 149.1.191.254149.1.191.255510
225149.1.192.0/23149.1.192.1 to 149.1.193.254149.1.193.255510
226149.1.194.0/23149.1.194.1 to 149.1.195.254149.1.195.255510
227149.1.196.0/23149.1.196.1 to 149.1.197.254149.1.197.255510
228149.1.198.0/23149.1.198.1 to 149.1.199.254149.1.199.255510
229149.1.200.0/23149.1.200.1 to 149.1.201.254149.1.201.255510
230149.1.202.0/23149.1.202.1 to 149.1.203.254149.1.203.255510
231149.1.204.0/23149.1.204.1 to 149.1.205.254149.1.205.255510
232149.1.206.0/23149.1.206.1 to 149.1.207.254149.1.207.255510
233149.1.208.0/23149.1.208.1 to 149.1.209.254149.1.209.255510
234149.1.210.0/23149.1.210.1 to 149.1.211.254149.1.211.255510
235149.1.212.0/23149.1.212.1 to 149.1.213.254149.1.213.255510
236149.1.214.0/23149.1.214.1 to 149.1.215.254149.1.215.255510
237149.1.216.0/23149.1.216.1 to 149.1.217.254149.1.217.255510
238149.1.218.0/23149.1.218.1 to 149.1.219.254149.1.219.255510
239149.1.220.0/23149.1.220.1 to 149.1.221.254149.1.221.255510
240149.1.222.0/23149.1.222.1 to 149.1.223.254149.1.223.255510
241149.1.224.0/23149.1.224.1 to 149.1.225.254149.1.225.255510
242149.1.226.0/23149.1.226.1 to 149.1.227.254149.1.227.255510
243149.1.228.0/23149.1.228.1 to 149.1.229.254149.1.229.255510
244149.1.230.0/23149.1.230.1 to 149.1.231.254149.1.231.255510
245149.1.232.0/23149.1.232.1 to 149.1.233.254149.1.233.255510
246149.1.234.0/23149.1.234.1 to 149.1.235.254149.1.235.255510
247149.1.236.0/23149.1.236.1 to 149.1.237.254149.1.237.255510
248149.1.238.0/23149.1.238.1 to 149.1.239.254149.1.239.255510
249149.1.240.0/23149.1.240.1 to 149.1.241.254149.1.241.255510
250149.1.242.0/23149.1.242.1 to 149.1.243.254149.1.243.255510
251149.1.244.0/23149.1.244.1 to 149.1.245.254149.1.245.255510
252149.1.246.0/23149.1.246.1 to 149.1.247.254149.1.247.255510
253149.1.248.0/23149.1.248.1 to 149.1.249.254149.1.249.255510
254149.1.250.0/23149.1.250.1 to 149.1.251.254149.1.251.255510
255149.1.252.0/23149.1.252.1 to 149.1.253.254149.1.253.255510
256149.1.254.0/23149.1.254.1 to 149.1.255.254149.1.255.255510

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.