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)10.2.121.64/26

network10.2.121.64/26

broadcast10.2.121.127

first host10.2.121.65

last host10.2.121.126

subnet mask255.255.255.192

wildcard0.0.0.63

addresses64

usable hosts62

classA

ipcalc 10.2.121.64/26

address00001010.00000010.01111001.01000000

subnet mask11111111.11111111.11111111.11000000

network00001010.00000010.01111001.01000000

broadcast00001010.00000010.01111001.01111111

green = network part, grey = host part

hex0x0a027940

decimal167934272

reverse dns64.121.2.10.in-addr.arpa

ipv4-mapped::ffff:a02:7940

/26 split into /32 · 64 subnets

close ×

#	network	host range	broadcast
1	10.2.121.64/32	10.2.121.64 – 10.2.121.64	10.2.121.64
2	10.2.121.65/32	10.2.121.65 – 10.2.121.65	10.2.121.65
3	10.2.121.66/32	10.2.121.66 – 10.2.121.66	10.2.121.66
4	10.2.121.67/32	10.2.121.67 – 10.2.121.67	10.2.121.67
5	10.2.121.68/32	10.2.121.68 – 10.2.121.68	10.2.121.68
6	10.2.121.69/32	10.2.121.69 – 10.2.121.69	10.2.121.69
7	10.2.121.70/32	10.2.121.70 – 10.2.121.70	10.2.121.70
8	10.2.121.71/32	10.2.121.71 – 10.2.121.71	10.2.121.71
9	10.2.121.72/32	10.2.121.72 – 10.2.121.72	10.2.121.72
10	10.2.121.73/32	10.2.121.73 – 10.2.121.73	10.2.121.73
11	10.2.121.74/32	10.2.121.74 – 10.2.121.74	10.2.121.74
12	10.2.121.75/32	10.2.121.75 – 10.2.121.75	10.2.121.75
13	10.2.121.76/32	10.2.121.76 – 10.2.121.76	10.2.121.76
14	10.2.121.77/32	10.2.121.77 – 10.2.121.77	10.2.121.77
15	10.2.121.78/32	10.2.121.78 – 10.2.121.78	10.2.121.78
16	10.2.121.79/32	10.2.121.79 – 10.2.121.79	10.2.121.79
17	10.2.121.80/32	10.2.121.80 – 10.2.121.80	10.2.121.80
18	10.2.121.81/32	10.2.121.81 – 10.2.121.81	10.2.121.81
19	10.2.121.82/32	10.2.121.82 – 10.2.121.82	10.2.121.82
20	10.2.121.83/32	10.2.121.83 – 10.2.121.83	10.2.121.83
21	10.2.121.84/32	10.2.121.84 – 10.2.121.84	10.2.121.84
22	10.2.121.85/32	10.2.121.85 – 10.2.121.85	10.2.121.85
23	10.2.121.86/32	10.2.121.86 – 10.2.121.86	10.2.121.86
24	10.2.121.87/32	10.2.121.87 – 10.2.121.87	10.2.121.87
25	10.2.121.88/32	10.2.121.88 – 10.2.121.88	10.2.121.88
26	10.2.121.89/32	10.2.121.89 – 10.2.121.89	10.2.121.89
27	10.2.121.90/32	10.2.121.90 – 10.2.121.90	10.2.121.90
28	10.2.121.91/32	10.2.121.91 – 10.2.121.91	10.2.121.91
29	10.2.121.92/32	10.2.121.92 – 10.2.121.92	10.2.121.92
30	10.2.121.93/32	10.2.121.93 – 10.2.121.93	10.2.121.93
31	10.2.121.94/32	10.2.121.94 – 10.2.121.94	10.2.121.94
32	10.2.121.95/32	10.2.121.95 – 10.2.121.95	10.2.121.95
33	10.2.121.96/32	10.2.121.96 – 10.2.121.96	10.2.121.96
34	10.2.121.97/32	10.2.121.97 – 10.2.121.97	10.2.121.97
35	10.2.121.98/32	10.2.121.98 – 10.2.121.98	10.2.121.98
36	10.2.121.99/32	10.2.121.99 – 10.2.121.99	10.2.121.99
37	10.2.121.100/32	10.2.121.100 – 10.2.121.100	10.2.121.100
38	10.2.121.101/32	10.2.121.101 – 10.2.121.101	10.2.121.101
39	10.2.121.102/32	10.2.121.102 – 10.2.121.102	10.2.121.102
40	10.2.121.103/32	10.2.121.103 – 10.2.121.103	10.2.121.103
41	10.2.121.104/32	10.2.121.104 – 10.2.121.104	10.2.121.104
42	10.2.121.105/32	10.2.121.105 – 10.2.121.105	10.2.121.105
43	10.2.121.106/32	10.2.121.106 – 10.2.121.106	10.2.121.106
44	10.2.121.107/32	10.2.121.107 – 10.2.121.107	10.2.121.107
45	10.2.121.108/32	10.2.121.108 – 10.2.121.108	10.2.121.108
46	10.2.121.109/32	10.2.121.109 – 10.2.121.109	10.2.121.109
47	10.2.121.110/32	10.2.121.110 – 10.2.121.110	10.2.121.110
48	10.2.121.111/32	10.2.121.111 – 10.2.121.111	10.2.121.111
49	10.2.121.112/32	10.2.121.112 – 10.2.121.112	10.2.121.112
50	10.2.121.113/32	10.2.121.113 – 10.2.121.113	10.2.121.113
51	10.2.121.114/32	10.2.121.114 – 10.2.121.114	10.2.121.114
52	10.2.121.115/32	10.2.121.115 – 10.2.121.115	10.2.121.115
53	10.2.121.116/32	10.2.121.116 – 10.2.121.116	10.2.121.116
54	10.2.121.117/32	10.2.121.117 – 10.2.121.117	10.2.121.117
55	10.2.121.118/32	10.2.121.118 – 10.2.121.118	10.2.121.118
56	10.2.121.119/32	10.2.121.119 – 10.2.121.119	10.2.121.119
57	10.2.121.120/32	10.2.121.120 – 10.2.121.120	10.2.121.120
58	10.2.121.121/32	10.2.121.121 – 10.2.121.121	10.2.121.121
59	10.2.121.122/32	10.2.121.122 – 10.2.121.122	10.2.121.122
60	10.2.121.123/32	10.2.121.123 – 10.2.121.123	10.2.121.123
61	10.2.121.124/32	10.2.121.124 – 10.2.121.124	10.2.121.124
62	10.2.121.125/32	10.2.121.125 – 10.2.121.125	10.2.121.125
63	10.2.121.126/32	10.2.121.126 – 10.2.121.126	10.2.121.126
64	10.2.121.127/32	10.2.121.127 – 10.2.121.127	10.2.121.127

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 /26
/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	-
/24	255.255.255.0	256	254	-
/25	255.255.255.128	128	126	-
/26	255.255.255.192	64	62	1
/27	255.255.255.224	32	30	2 split →
/28	255.255.255.240	16	14	4 split →
/29	255.255.255.248	8	6	8 split →
/30	255.255.255.252	4	2	16 split →
/31	255.255.255.254	2	2	32 split →
/32	255.255.255.255	1	1	64 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 →