0.222.128.0/23

Public

Class A — /23 prefix — 510 usable hosts

Network Address

0.222.128.0

Broadcast Address

0.222.129.255

Subnet Mask

255.255.254.0

Usable Hosts

510

First Usable IP

0.222.128.1

Last Usable IP

0.222.129.254

Total IPs

512

Prefix Length

/23

Network address — the base address of the block (0.222.128.0). All devices in this subnet share this prefix. Cannot be assigned to a host.

Broadcast address — packets sent to 0.222.129.255 are delivered to every device in the subnet. Also reserved — not assignable.

Usable hosts — the 510 addresses between those two that you can assign to servers, VMs, or interfaces.

Subnet mask — 255.255.254.0 is the dotted-decimal equivalent of /23. Older tools and Cisco configs use this format instead of CIDR slash notation.

Full Details

CIDR Notation	0.222.128.0/23
Network Address	0.222.128.0
Broadcast Address	0.222.129.255
Subnet Mask	255.255.254.0
Wildcard Mask	0.0.1.255
Prefix Length	/23
IP Address Class	Class A
Total IP Addresses	512
Usable Host Addresses	510
First Usable IP	0.222.128.1
Last Usable IP	0.222.129.254
Network (Hex)	0x00DE8000
Broadcast (Hex)	0x00DE81FF
Address Type	Public / Globally Routable

Binary Representation

Network Address

00000000.11011110 00000000.11011110.10000000.00000000

Subnet Mask

11111111.11111111.11111110.00000000

The first 23 bits (1s in the mask) identify the network. The remaining 9 bits identify hosts within the network.

Split into Equal Subnets

Split 0.222.128.0/23 into 2 equal /24 subnets (254 usable hosts each).

#	CIDR	Network	First Usable	Last Usable	Broadcast	Hosts
1	0.222.128.0/24	0.222.128.0	0.222.128.1	0.222.128.254	0.222.128.255	254
2	0.222.129.0/24	0.222.129.0	0.222.129.1	0.222.129.254	0.222.129.255	254

Split 0.222.128.0/23 into 4 equal /25 subnets (126 usable hosts each).

#	CIDR	Network	First Usable	Last Usable	Broadcast	Hosts
1	0.222.128.0/25	0.222.128.0	0.222.128.1	0.222.128.126	0.222.128.127	126
2	0.222.128.128/25	0.222.128.128	0.222.128.129	0.222.128.254	0.222.128.255	126
3	0.222.129.0/25	0.222.129.0	0.222.129.1	0.222.129.126	0.222.129.127	126
4	0.222.129.128/25	0.222.129.128	0.222.129.129	0.222.129.254	0.222.129.255	126

Split 0.222.128.0/23 into 8 equal /26 subnets (62 usable hosts each).

#	CIDR	Network	First Usable	Last Usable	Broadcast	Hosts
1	0.222.128.0/26	0.222.128.0	0.222.128.1	0.222.128.62	0.222.128.63	62
2	0.222.128.64/26	0.222.128.64	0.222.128.65	0.222.128.126	0.222.128.127	62
3	0.222.128.128/26	0.222.128.128	0.222.128.129	0.222.128.190	0.222.128.191	62
4	0.222.128.192/26	0.222.128.192	0.222.128.193	0.222.128.254	0.222.128.255	62
5	0.222.129.0/26	0.222.129.0	0.222.129.1	0.222.129.62	0.222.129.63	62
6	0.222.129.64/26	0.222.129.64	0.222.129.65	0.222.129.126	0.222.129.127	62
7	0.222.129.128/26	0.222.129.128	0.222.129.129	0.222.129.190	0.222.129.191	62
8	0.222.129.192/26	0.222.129.192	0.222.129.193	0.222.129.254	0.222.129.255	62

Split 0.222.128.0/23 into 16 equal /27 subnets (30 usable hosts each).

#	CIDR	Network	First Usable	Last Usable	Broadcast	Hosts
1	0.222.128.0/27	0.222.128.0	0.222.128.1	0.222.128.30	0.222.128.31	30
2	0.222.128.32/27	0.222.128.32	0.222.128.33	0.222.128.62	0.222.128.63	30
3	0.222.128.64/27	0.222.128.64	0.222.128.65	0.222.128.94	0.222.128.95	30
4	0.222.128.96/27	0.222.128.96	0.222.128.97	0.222.128.126	0.222.128.127	30
5	0.222.128.128/27	0.222.128.128	0.222.128.129	0.222.128.158	0.222.128.159	30
6	0.222.128.160/27	0.222.128.160	0.222.128.161	0.222.128.190	0.222.128.191	30
7	0.222.128.192/27	0.222.128.192	0.222.128.193	0.222.128.222	0.222.128.223	30
8	0.222.128.224/27	0.222.128.224	0.222.128.225	0.222.128.254	0.222.128.255	30
9	0.222.129.0/27	0.222.129.0	0.222.129.1	0.222.129.30	0.222.129.31	30
10	0.222.129.32/27	0.222.129.32	0.222.129.33	0.222.129.62	0.222.129.63	30
11	0.222.129.64/27	0.222.129.64	0.222.129.65	0.222.129.94	0.222.129.95	30
12	0.222.129.96/27	0.222.129.96	0.222.129.97	0.222.129.126	0.222.129.127	30
13	0.222.129.128/27	0.222.129.128	0.222.129.129	0.222.129.158	0.222.129.159	30
14	0.222.129.160/27	0.222.129.160	0.222.129.161	0.222.129.190	0.222.129.191	30
15	0.222.129.192/27	0.222.129.192	0.222.129.193	0.222.129.222	0.222.129.223	30
16	0.222.129.224/27	0.222.129.224	0.222.129.225	0.222.129.254	0.222.129.255	30

/23 Subnet Reference

Total IPs 512

Usable Hosts 510

Subnet Mask 255.255.254.0

Wildcard 0.0.1.255

Full /23 reference →

Related Ranges

Parent /22 block 0.222.128.0/22 Sibling /23 block 0.222.130.0/23

Adjacent Prefix Sizes

/21 2,046 hosts /22 1,022 hosts /23 510 hosts /24 254 hosts /25 126 hosts