IPv4 Subnet Calculator

Enter an IP with a CIDR prefix or a subnet mask to see its network, broadcast, host range, and host count. You can also split the network into smaller subnets.

Try:192.168.1.10/24 10.0.0.0/8 172.16.5.4/20 203.0.113.9/29

IPv6 calculator →

private IP (RFC 1918)10.2.8.0/23

network10.2.8.0/23

broadcast10.2.9.255

first host10.2.8.1

last host10.2.9.254

subnet mask255.255.254.0

wildcard0.0.1.255

addresses512

usable hosts510

classA

ipcalc 10.2.8.0/23

address00001010.00000010.00001000.00000000

subnet mask11111111.11111111.11111110.00000000

network00001010.00000010.00001000.00000000

broadcast00001010.00000010.00001001.11111111

green = network part, grey = host part

hex0x0a020800

decimal167905280

reverse dns0.8.2.10.in-addr.arpa

ipv4-mapped::ffff:a02:800

/23 split into /30 · 128 subnets

close ×

#	network	host range	broadcast
1	10.2.8.0/30	10.2.8.1 – 10.2.8.2	10.2.8.3
2	10.2.8.4/30	10.2.8.5 – 10.2.8.6	10.2.8.7
3	10.2.8.8/30	10.2.8.9 – 10.2.8.10	10.2.8.11
4	10.2.8.12/30	10.2.8.13 – 10.2.8.14	10.2.8.15
5	10.2.8.16/30	10.2.8.17 – 10.2.8.18	10.2.8.19
6	10.2.8.20/30	10.2.8.21 – 10.2.8.22	10.2.8.23
7	10.2.8.24/30	10.2.8.25 – 10.2.8.26	10.2.8.27
8	10.2.8.28/30	10.2.8.29 – 10.2.8.30	10.2.8.31
9	10.2.8.32/30	10.2.8.33 – 10.2.8.34	10.2.8.35
10	10.2.8.36/30	10.2.8.37 – 10.2.8.38	10.2.8.39
11	10.2.8.40/30	10.2.8.41 – 10.2.8.42	10.2.8.43
12	10.2.8.44/30	10.2.8.45 – 10.2.8.46	10.2.8.47
13	10.2.8.48/30	10.2.8.49 – 10.2.8.50	10.2.8.51
14	10.2.8.52/30	10.2.8.53 – 10.2.8.54	10.2.8.55
15	10.2.8.56/30	10.2.8.57 – 10.2.8.58	10.2.8.59
16	10.2.8.60/30	10.2.8.61 – 10.2.8.62	10.2.8.63
17	10.2.8.64/30	10.2.8.65 – 10.2.8.66	10.2.8.67
18	10.2.8.68/30	10.2.8.69 – 10.2.8.70	10.2.8.71
19	10.2.8.72/30	10.2.8.73 – 10.2.8.74	10.2.8.75
20	10.2.8.76/30	10.2.8.77 – 10.2.8.78	10.2.8.79
21	10.2.8.80/30	10.2.8.81 – 10.2.8.82	10.2.8.83
22	10.2.8.84/30	10.2.8.85 – 10.2.8.86	10.2.8.87
23	10.2.8.88/30	10.2.8.89 – 10.2.8.90	10.2.8.91
24	10.2.8.92/30	10.2.8.93 – 10.2.8.94	10.2.8.95
25	10.2.8.96/30	10.2.8.97 – 10.2.8.98	10.2.8.99
26	10.2.8.100/30	10.2.8.101 – 10.2.8.102	10.2.8.103
27	10.2.8.104/30	10.2.8.105 – 10.2.8.106	10.2.8.107
28	10.2.8.108/30	10.2.8.109 – 10.2.8.110	10.2.8.111
29	10.2.8.112/30	10.2.8.113 – 10.2.8.114	10.2.8.115
30	10.2.8.116/30	10.2.8.117 – 10.2.8.118	10.2.8.119
31	10.2.8.120/30	10.2.8.121 – 10.2.8.122	10.2.8.123
32	10.2.8.124/30	10.2.8.125 – 10.2.8.126	10.2.8.127
33	10.2.8.128/30	10.2.8.129 – 10.2.8.130	10.2.8.131
34	10.2.8.132/30	10.2.8.133 – 10.2.8.134	10.2.8.135
35	10.2.8.136/30	10.2.8.137 – 10.2.8.138	10.2.8.139
36	10.2.8.140/30	10.2.8.141 – 10.2.8.142	10.2.8.143
37	10.2.8.144/30	10.2.8.145 – 10.2.8.146	10.2.8.147
38	10.2.8.148/30	10.2.8.149 – 10.2.8.150	10.2.8.151
39	10.2.8.152/30	10.2.8.153 – 10.2.8.154	10.2.8.155
40	10.2.8.156/30	10.2.8.157 – 10.2.8.158	10.2.8.159
41	10.2.8.160/30	10.2.8.161 – 10.2.8.162	10.2.8.163
42	10.2.8.164/30	10.2.8.165 – 10.2.8.166	10.2.8.167
43	10.2.8.168/30	10.2.8.169 – 10.2.8.170	10.2.8.171
44	10.2.8.172/30	10.2.8.173 – 10.2.8.174	10.2.8.175
45	10.2.8.176/30	10.2.8.177 – 10.2.8.178	10.2.8.179
46	10.2.8.180/30	10.2.8.181 – 10.2.8.182	10.2.8.183
47	10.2.8.184/30	10.2.8.185 – 10.2.8.186	10.2.8.187
48	10.2.8.188/30	10.2.8.189 – 10.2.8.190	10.2.8.191
49	10.2.8.192/30	10.2.8.193 – 10.2.8.194	10.2.8.195
50	10.2.8.196/30	10.2.8.197 – 10.2.8.198	10.2.8.199
51	10.2.8.200/30	10.2.8.201 – 10.2.8.202	10.2.8.203
52	10.2.8.204/30	10.2.8.205 – 10.2.8.206	10.2.8.207
53	10.2.8.208/30	10.2.8.209 – 10.2.8.210	10.2.8.211
54	10.2.8.212/30	10.2.8.213 – 10.2.8.214	10.2.8.215
55	10.2.8.216/30	10.2.8.217 – 10.2.8.218	10.2.8.219
56	10.2.8.220/30	10.2.8.221 – 10.2.8.222	10.2.8.223
57	10.2.8.224/30	10.2.8.225 – 10.2.8.226	10.2.8.227
58	10.2.8.228/30	10.2.8.229 – 10.2.8.230	10.2.8.231
59	10.2.8.232/30	10.2.8.233 – 10.2.8.234	10.2.8.235
60	10.2.8.236/30	10.2.8.237 – 10.2.8.238	10.2.8.239
61	10.2.8.240/30	10.2.8.241 – 10.2.8.242	10.2.8.243
62	10.2.8.244/30	10.2.8.245 – 10.2.8.246	10.2.8.247
63	10.2.8.248/30	10.2.8.249 – 10.2.8.250	10.2.8.251
64	10.2.8.252/30	10.2.8.253 – 10.2.8.254	10.2.8.255
65	10.2.9.0/30	10.2.9.1 – 10.2.9.2	10.2.9.3
66	10.2.9.4/30	10.2.9.5 – 10.2.9.6	10.2.9.7
67	10.2.9.8/30	10.2.9.9 – 10.2.9.10	10.2.9.11
68	10.2.9.12/30	10.2.9.13 – 10.2.9.14	10.2.9.15
69	10.2.9.16/30	10.2.9.17 – 10.2.9.18	10.2.9.19
70	10.2.9.20/30	10.2.9.21 – 10.2.9.22	10.2.9.23
71	10.2.9.24/30	10.2.9.25 – 10.2.9.26	10.2.9.27
72	10.2.9.28/30	10.2.9.29 – 10.2.9.30	10.2.9.31
73	10.2.9.32/30	10.2.9.33 – 10.2.9.34	10.2.9.35
74	10.2.9.36/30	10.2.9.37 – 10.2.9.38	10.2.9.39
75	10.2.9.40/30	10.2.9.41 – 10.2.9.42	10.2.9.43
76	10.2.9.44/30	10.2.9.45 – 10.2.9.46	10.2.9.47
77	10.2.9.48/30	10.2.9.49 – 10.2.9.50	10.2.9.51
78	10.2.9.52/30	10.2.9.53 – 10.2.9.54	10.2.9.55
79	10.2.9.56/30	10.2.9.57 – 10.2.9.58	10.2.9.59
80	10.2.9.60/30	10.2.9.61 – 10.2.9.62	10.2.9.63
81	10.2.9.64/30	10.2.9.65 – 10.2.9.66	10.2.9.67
82	10.2.9.68/30	10.2.9.69 – 10.2.9.70	10.2.9.71
83	10.2.9.72/30	10.2.9.73 – 10.2.9.74	10.2.9.75
84	10.2.9.76/30	10.2.9.77 – 10.2.9.78	10.2.9.79
85	10.2.9.80/30	10.2.9.81 – 10.2.9.82	10.2.9.83
86	10.2.9.84/30	10.2.9.85 – 10.2.9.86	10.2.9.87
87	10.2.9.88/30	10.2.9.89 – 10.2.9.90	10.2.9.91
88	10.2.9.92/30	10.2.9.93 – 10.2.9.94	10.2.9.95
89	10.2.9.96/30	10.2.9.97 – 10.2.9.98	10.2.9.99
90	10.2.9.100/30	10.2.9.101 – 10.2.9.102	10.2.9.103
91	10.2.9.104/30	10.2.9.105 – 10.2.9.106	10.2.9.107
92	10.2.9.108/30	10.2.9.109 – 10.2.9.110	10.2.9.111
93	10.2.9.112/30	10.2.9.113 – 10.2.9.114	10.2.9.115
94	10.2.9.116/30	10.2.9.117 – 10.2.9.118	10.2.9.119
95	10.2.9.120/30	10.2.9.121 – 10.2.9.122	10.2.9.123
96	10.2.9.124/30	10.2.9.125 – 10.2.9.126	10.2.9.127
97	10.2.9.128/30	10.2.9.129 – 10.2.9.130	10.2.9.131
98	10.2.9.132/30	10.2.9.133 – 10.2.9.134	10.2.9.135
99	10.2.9.136/30	10.2.9.137 – 10.2.9.138	10.2.9.139
100	10.2.9.140/30	10.2.9.141 – 10.2.9.142	10.2.9.143
101	10.2.9.144/30	10.2.9.145 – 10.2.9.146	10.2.9.147
102	10.2.9.148/30	10.2.9.149 – 10.2.9.150	10.2.9.151
103	10.2.9.152/30	10.2.9.153 – 10.2.9.154	10.2.9.155
104	10.2.9.156/30	10.2.9.157 – 10.2.9.158	10.2.9.159
105	10.2.9.160/30	10.2.9.161 – 10.2.9.162	10.2.9.163
106	10.2.9.164/30	10.2.9.165 – 10.2.9.166	10.2.9.167
107	10.2.9.168/30	10.2.9.169 – 10.2.9.170	10.2.9.171
108	10.2.9.172/30	10.2.9.173 – 10.2.9.174	10.2.9.175
109	10.2.9.176/30	10.2.9.177 – 10.2.9.178	10.2.9.179
110	10.2.9.180/30	10.2.9.181 – 10.2.9.182	10.2.9.183
111	10.2.9.184/30	10.2.9.185 – 10.2.9.186	10.2.9.187
112	10.2.9.188/30	10.2.9.189 – 10.2.9.190	10.2.9.191
113	10.2.9.192/30	10.2.9.193 – 10.2.9.194	10.2.9.195
114	10.2.9.196/30	10.2.9.197 – 10.2.9.198	10.2.9.199
115	10.2.9.200/30	10.2.9.201 – 10.2.9.202	10.2.9.203
116	10.2.9.204/30	10.2.9.205 – 10.2.9.206	10.2.9.207
117	10.2.9.208/30	10.2.9.209 – 10.2.9.210	10.2.9.211
118	10.2.9.212/30	10.2.9.213 – 10.2.9.214	10.2.9.215
119	10.2.9.216/30	10.2.9.217 – 10.2.9.218	10.2.9.219
120	10.2.9.220/30	10.2.9.221 – 10.2.9.222	10.2.9.223
121	10.2.9.224/30	10.2.9.225 – 10.2.9.226	10.2.9.227
122	10.2.9.228/30	10.2.9.229 – 10.2.9.230	10.2.9.231
123	10.2.9.232/30	10.2.9.233 – 10.2.9.234	10.2.9.235
124	10.2.9.236/30	10.2.9.237 – 10.2.9.238	10.2.9.239
125	10.2.9.240/30	10.2.9.241 – 10.2.9.242	10.2.9.243
126	10.2.9.244/30	10.2.9.245 – 10.2.9.246	10.2.9.247
127	10.2.9.248/30	10.2.9.249 – 10.2.9.250	10.2.9.251
128	10.2.9.252/30	10.2.9.253 – 10.2.9.254	10.2.9.255

01 / table

IPv4 CIDR prefix table.

Click a prefix longer than your network to split it into subnets.

prefix	subnet mask	addresses	hosts	in your /23
/0	0.0.0.0	4,294,967,296	4,294,967,294	-
/1	128.0.0.0	2,147,483,648	2,147,483,646	-
/2	192.0.0.0	1,073,741,824	1,073,741,822	-
/3	224.0.0.0	536,870,912	536,870,910	-
/4	240.0.0.0	268,435,456	268,435,454	-
/5	248.0.0.0	134,217,728	134,217,726	-
/6	252.0.0.0	67,108,864	67,108,862	-
/7	254.0.0.0	33,554,432	33,554,430	-
/8	255.0.0.0	16,777,216	16,777,214	-
/9	255.128.0.0	8,388,608	8,388,606	-
/10	255.192.0.0	4,194,304	4,194,302	-
/11	255.224.0.0	2,097,152	2,097,150	-
/12	255.240.0.0	1,048,576	1,048,574	-
/13	255.248.0.0	524,288	524,286	-
/14	255.252.0.0	262,144	262,142	-
/15	255.254.0.0	131,072	131,070	-
/16	255.255.0.0	65,536	65,534	-
/17	255.255.128.0	32,768	32,766	-
/18	255.255.192.0	16,384	16,382	-
/19	255.255.224.0	8,192	8,190	-
/20	255.255.240.0	4,096	4,094	-
/21	255.255.248.0	2,048	2,046	-
/22	255.255.252.0	1,024	1,022	-
/23	255.255.254.0	512	510	1
/24	255.255.255.0	256	254	2 split →
/25	255.255.255.128	128	126	4 split →
/26	255.255.255.192	64	62	8 split →
/27	255.255.255.224	32	30	16 split →
/28	255.255.255.240	16	14	32 split →
/29	255.255.255.248	8	6	64 split →
/30	255.255.255.252	4	2	128 split →
/31	255.255.255.254	2	2	256 split →
/32	255.255.255.255	1	1	512 split →

02 / faq

About this calculator.

How do I use this subnet calculator?

▼

Type an IP address followed by a prefix, like 192.168.1.10/24, or by a subnet mask, like 192.168.1.10 255.255.255.0. Without a prefix it uses /24. Click a row in the table to split the network into smaller subnets.

Why are usable hosts always 2 fewer?

▼

The first address in a subnet is the network address and the last is the broadcast address, so neither can go to a device. The exceptions are /31 (point-to-point links, RFC 3021) and /32 (a single address), which use every address.

Can I use it from a terminal?

▼

Yes. curl 'ipku.in/en/tools/ipv4-subnet-calculator?q=192.168.1.10/24' returns the result as plain text.

Learn how to work it out →