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)10.0.30.0/23

network10.0.30.0/23

broadcast10.0.31.255

first host10.0.30.1

last host10.0.31.254

subnet mask255.255.254.0

wildcard0.0.1.255

addresses512

usable hosts510

classA

ipcalc 10.0.30.0/23

address00001010.00000000.00011110.00000000

subnet mask11111111.11111111.11111110.00000000

network00001010.00000000.00011110.00000000

broadcast00001010.00000000.00011111.11111111

green = network part, grey = host part

hex0x0a001e00

decimal167779840

reverse dns0.30.0.10.in-addr.arpa

ipv4-mapped::ffff:a00:1e00

/23 split into /30 · 128 subnets

close ×

#	network	host range	broadcast
1	10.0.30.0/30	10.0.30.1 – 10.0.30.2	10.0.30.3
2	10.0.30.4/30	10.0.30.5 – 10.0.30.6	10.0.30.7
3	10.0.30.8/30	10.0.30.9 – 10.0.30.10	10.0.30.11
4	10.0.30.12/30	10.0.30.13 – 10.0.30.14	10.0.30.15
5	10.0.30.16/30	10.0.30.17 – 10.0.30.18	10.0.30.19
6	10.0.30.20/30	10.0.30.21 – 10.0.30.22	10.0.30.23
7	10.0.30.24/30	10.0.30.25 – 10.0.30.26	10.0.30.27
8	10.0.30.28/30	10.0.30.29 – 10.0.30.30	10.0.30.31
9	10.0.30.32/30	10.0.30.33 – 10.0.30.34	10.0.30.35
10	10.0.30.36/30	10.0.30.37 – 10.0.30.38	10.0.30.39
11	10.0.30.40/30	10.0.30.41 – 10.0.30.42	10.0.30.43
12	10.0.30.44/30	10.0.30.45 – 10.0.30.46	10.0.30.47
13	10.0.30.48/30	10.0.30.49 – 10.0.30.50	10.0.30.51
14	10.0.30.52/30	10.0.30.53 – 10.0.30.54	10.0.30.55
15	10.0.30.56/30	10.0.30.57 – 10.0.30.58	10.0.30.59
16	10.0.30.60/30	10.0.30.61 – 10.0.30.62	10.0.30.63
17	10.0.30.64/30	10.0.30.65 – 10.0.30.66	10.0.30.67
18	10.0.30.68/30	10.0.30.69 – 10.0.30.70	10.0.30.71
19	10.0.30.72/30	10.0.30.73 – 10.0.30.74	10.0.30.75
20	10.0.30.76/30	10.0.30.77 – 10.0.30.78	10.0.30.79
21	10.0.30.80/30	10.0.30.81 – 10.0.30.82	10.0.30.83
22	10.0.30.84/30	10.0.30.85 – 10.0.30.86	10.0.30.87
23	10.0.30.88/30	10.0.30.89 – 10.0.30.90	10.0.30.91
24	10.0.30.92/30	10.0.30.93 – 10.0.30.94	10.0.30.95
25	10.0.30.96/30	10.0.30.97 – 10.0.30.98	10.0.30.99
26	10.0.30.100/30	10.0.30.101 – 10.0.30.102	10.0.30.103
27	10.0.30.104/30	10.0.30.105 – 10.0.30.106	10.0.30.107
28	10.0.30.108/30	10.0.30.109 – 10.0.30.110	10.0.30.111
29	10.0.30.112/30	10.0.30.113 – 10.0.30.114	10.0.30.115
30	10.0.30.116/30	10.0.30.117 – 10.0.30.118	10.0.30.119
31	10.0.30.120/30	10.0.30.121 – 10.0.30.122	10.0.30.123
32	10.0.30.124/30	10.0.30.125 – 10.0.30.126	10.0.30.127
33	10.0.30.128/30	10.0.30.129 – 10.0.30.130	10.0.30.131
34	10.0.30.132/30	10.0.30.133 – 10.0.30.134	10.0.30.135
35	10.0.30.136/30	10.0.30.137 – 10.0.30.138	10.0.30.139
36	10.0.30.140/30	10.0.30.141 – 10.0.30.142	10.0.30.143
37	10.0.30.144/30	10.0.30.145 – 10.0.30.146	10.0.30.147
38	10.0.30.148/30	10.0.30.149 – 10.0.30.150	10.0.30.151
39	10.0.30.152/30	10.0.30.153 – 10.0.30.154	10.0.30.155
40	10.0.30.156/30	10.0.30.157 – 10.0.30.158	10.0.30.159
41	10.0.30.160/30	10.0.30.161 – 10.0.30.162	10.0.30.163
42	10.0.30.164/30	10.0.30.165 – 10.0.30.166	10.0.30.167
43	10.0.30.168/30	10.0.30.169 – 10.0.30.170	10.0.30.171
44	10.0.30.172/30	10.0.30.173 – 10.0.30.174	10.0.30.175
45	10.0.30.176/30	10.0.30.177 – 10.0.30.178	10.0.30.179
46	10.0.30.180/30	10.0.30.181 – 10.0.30.182	10.0.30.183
47	10.0.30.184/30	10.0.30.185 – 10.0.30.186	10.0.30.187
48	10.0.30.188/30	10.0.30.189 – 10.0.30.190	10.0.30.191
49	10.0.30.192/30	10.0.30.193 – 10.0.30.194	10.0.30.195
50	10.0.30.196/30	10.0.30.197 – 10.0.30.198	10.0.30.199
51	10.0.30.200/30	10.0.30.201 – 10.0.30.202	10.0.30.203
52	10.0.30.204/30	10.0.30.205 – 10.0.30.206	10.0.30.207
53	10.0.30.208/30	10.0.30.209 – 10.0.30.210	10.0.30.211
54	10.0.30.212/30	10.0.30.213 – 10.0.30.214	10.0.30.215
55	10.0.30.216/30	10.0.30.217 – 10.0.30.218	10.0.30.219
56	10.0.30.220/30	10.0.30.221 – 10.0.30.222	10.0.30.223
57	10.0.30.224/30	10.0.30.225 – 10.0.30.226	10.0.30.227
58	10.0.30.228/30	10.0.30.229 – 10.0.30.230	10.0.30.231
59	10.0.30.232/30	10.0.30.233 – 10.0.30.234	10.0.30.235
60	10.0.30.236/30	10.0.30.237 – 10.0.30.238	10.0.30.239
61	10.0.30.240/30	10.0.30.241 – 10.0.30.242	10.0.30.243
62	10.0.30.244/30	10.0.30.245 – 10.0.30.246	10.0.30.247
63	10.0.30.248/30	10.0.30.249 – 10.0.30.250	10.0.30.251
64	10.0.30.252/30	10.0.30.253 – 10.0.30.254	10.0.30.255
65	10.0.31.0/30	10.0.31.1 – 10.0.31.2	10.0.31.3
66	10.0.31.4/30	10.0.31.5 – 10.0.31.6	10.0.31.7
67	10.0.31.8/30	10.0.31.9 – 10.0.31.10	10.0.31.11
68	10.0.31.12/30	10.0.31.13 – 10.0.31.14	10.0.31.15
69	10.0.31.16/30	10.0.31.17 – 10.0.31.18	10.0.31.19
70	10.0.31.20/30	10.0.31.21 – 10.0.31.22	10.0.31.23
71	10.0.31.24/30	10.0.31.25 – 10.0.31.26	10.0.31.27
72	10.0.31.28/30	10.0.31.29 – 10.0.31.30	10.0.31.31
73	10.0.31.32/30	10.0.31.33 – 10.0.31.34	10.0.31.35
74	10.0.31.36/30	10.0.31.37 – 10.0.31.38	10.0.31.39
75	10.0.31.40/30	10.0.31.41 – 10.0.31.42	10.0.31.43
76	10.0.31.44/30	10.0.31.45 – 10.0.31.46	10.0.31.47
77	10.0.31.48/30	10.0.31.49 – 10.0.31.50	10.0.31.51
78	10.0.31.52/30	10.0.31.53 – 10.0.31.54	10.0.31.55
79	10.0.31.56/30	10.0.31.57 – 10.0.31.58	10.0.31.59
80	10.0.31.60/30	10.0.31.61 – 10.0.31.62	10.0.31.63
81	10.0.31.64/30	10.0.31.65 – 10.0.31.66	10.0.31.67
82	10.0.31.68/30	10.0.31.69 – 10.0.31.70	10.0.31.71
83	10.0.31.72/30	10.0.31.73 – 10.0.31.74	10.0.31.75
84	10.0.31.76/30	10.0.31.77 – 10.0.31.78	10.0.31.79
85	10.0.31.80/30	10.0.31.81 – 10.0.31.82	10.0.31.83
86	10.0.31.84/30	10.0.31.85 – 10.0.31.86	10.0.31.87
87	10.0.31.88/30	10.0.31.89 – 10.0.31.90	10.0.31.91
88	10.0.31.92/30	10.0.31.93 – 10.0.31.94	10.0.31.95
89	10.0.31.96/30	10.0.31.97 – 10.0.31.98	10.0.31.99
90	10.0.31.100/30	10.0.31.101 – 10.0.31.102	10.0.31.103
91	10.0.31.104/30	10.0.31.105 – 10.0.31.106	10.0.31.107
92	10.0.31.108/30	10.0.31.109 – 10.0.31.110	10.0.31.111
93	10.0.31.112/30	10.0.31.113 – 10.0.31.114	10.0.31.115
94	10.0.31.116/30	10.0.31.117 – 10.0.31.118	10.0.31.119
95	10.0.31.120/30	10.0.31.121 – 10.0.31.122	10.0.31.123
96	10.0.31.124/30	10.0.31.125 – 10.0.31.126	10.0.31.127
97	10.0.31.128/30	10.0.31.129 – 10.0.31.130	10.0.31.131
98	10.0.31.132/30	10.0.31.133 – 10.0.31.134	10.0.31.135
99	10.0.31.136/30	10.0.31.137 – 10.0.31.138	10.0.31.139
100	10.0.31.140/30	10.0.31.141 – 10.0.31.142	10.0.31.143
101	10.0.31.144/30	10.0.31.145 – 10.0.31.146	10.0.31.147
102	10.0.31.148/30	10.0.31.149 – 10.0.31.150	10.0.31.151
103	10.0.31.152/30	10.0.31.153 – 10.0.31.154	10.0.31.155
104	10.0.31.156/30	10.0.31.157 – 10.0.31.158	10.0.31.159
105	10.0.31.160/30	10.0.31.161 – 10.0.31.162	10.0.31.163
106	10.0.31.164/30	10.0.31.165 – 10.0.31.166	10.0.31.167
107	10.0.31.168/30	10.0.31.169 – 10.0.31.170	10.0.31.171
108	10.0.31.172/30	10.0.31.173 – 10.0.31.174	10.0.31.175
109	10.0.31.176/30	10.0.31.177 – 10.0.31.178	10.0.31.179
110	10.0.31.180/30	10.0.31.181 – 10.0.31.182	10.0.31.183
111	10.0.31.184/30	10.0.31.185 – 10.0.31.186	10.0.31.187
112	10.0.31.188/30	10.0.31.189 – 10.0.31.190	10.0.31.191
113	10.0.31.192/30	10.0.31.193 – 10.0.31.194	10.0.31.195
114	10.0.31.196/30	10.0.31.197 – 10.0.31.198	10.0.31.199
115	10.0.31.200/30	10.0.31.201 – 10.0.31.202	10.0.31.203
116	10.0.31.204/30	10.0.31.205 – 10.0.31.206	10.0.31.207
117	10.0.31.208/30	10.0.31.209 – 10.0.31.210	10.0.31.211
118	10.0.31.212/30	10.0.31.213 – 10.0.31.214	10.0.31.215
119	10.0.31.216/30	10.0.31.217 – 10.0.31.218	10.0.31.219
120	10.0.31.220/30	10.0.31.221 – 10.0.31.222	10.0.31.223
121	10.0.31.224/30	10.0.31.225 – 10.0.31.226	10.0.31.227
122	10.0.31.228/30	10.0.31.229 – 10.0.31.230	10.0.31.231
123	10.0.31.232/30	10.0.31.233 – 10.0.31.234	10.0.31.235
124	10.0.31.236/30	10.0.31.237 – 10.0.31.238	10.0.31.239
125	10.0.31.240/30	10.0.31.241 – 10.0.31.242	10.0.31.243
126	10.0.31.244/30	10.0.31.245 – 10.0.31.246	10.0.31.247
127	10.0.31.248/30	10.0.31.249 – 10.0.31.250	10.0.31.251
128	10.0.31.252/30	10.0.31.253 – 10.0.31.254	10.0.31.255

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 →