What is a /24 subnet? 256 IPs, the home-network default, and when to use it
A /24 is the right default for any network with fewer than 200 devices. It's universally compatible, easy to reason about (the last octet is the host portion), and gives you headroom without being wasteful. If you're approaching 200 devices, step up to a /23 rather than adding a second /24 and dealing with inter-VLAN routing.
A /24 subnet, written as 255.255.255.0 in dotted-decimal notation, provides 256 total addresses with 254 usable for hosts (one reserved for the network address and one for broadcast). This is the default subnet size on virtually every consumer router and the most common subnet on earth.
By TechCompare · Updated
How this is calculated
The /24 is ubiquitous because it's simple and fits the vast majority of home and small-office networks. With 254 usable addresses, you can connect every phone, laptop, smart TV, IoT device, and printer in a typical household with room to spare. In CIDR notation, /24 means the first 24 bits of the IP address are the network portion, leaving 8 bits for hosts (2^8 = 256). Moving to a /23 doubles your address space to 510 usable hosts; moving to a /25 halves it to 126.
Verdict
A /24 is the right default for any network with fewer than 200 devices. It's universally compatible, easy to reason about (the last octet is the host portion), and gives you headroom without being wasteful. If you're approaching 200 devices, step up to a /23 rather than adding a second /24 and dealing with inter-VLAN routing.
More Subnet scenarios
Frequently asked questions
How many usable IPs in a /24?
Related tools
Display Bandwidth Calculator
Check if your HDMI/DP cable supports your resolution and refresh rate.
Use tool ➜Data Transfer Calculator
Estimate transfer times for files over USB, WiFi, Ethernet, and more.
Use tool ➜CHMOD Configurator
Calculate Linux file permissions using checkboxes, octal numbers, or symbolic notation.
Use tool ➜