What Is a Smart Plug and How Does It Work?

Smart plugs are the fairy godmothers of the smart home world. One little plug can transform simple household devices into smart ones you can control with a magical flick of your wrist (or at least a tap on your phone).

Different from a smart outlet permanently installed on your wall, the best smart plugs are great for flexibility and customization.

Both smart plugs and full-on smart outlets can function as adaptors, making it possible for you to remotely control the energy flow of whatever you plug into them. Even more than energy monitoring, a smart plug gives you complete control over a device’s functions and features.

Wondering why you’d even need to make a smart device from a simple one? We'll walk through what a smart plug is, how people like to use them to smarten up their homes, and some of the most popular models so you can decide for yourself.

A smart plug is an affordable way to begin building your smart home system without having to buy a bunch of pricey new appliances. A few reasonably priced smart plugs can support a bunch of different devices you already own. You can also use smart plugs to supplement your existing smart home or home security system.

Smart plugs are also easy to install, and then you can use mobile apps and voice assistants like Alexa to control your devices.

If you’re interested in making your life easier without adding unnecessary expenses, here’s what you should keep in mind while you’re shopping:

• Does it work with your smart speaker? Do you already own a Google Home or Amazon Echo? Not all smart plugs connect to the same voice assistant, so make sure the plug you buy is compatible with your current virtual assistant.
• Where will you use your smart plug? If you plan to use it outside, make sure you get an outdoor smart plug with weather resistance. It also won’t hurt to check the plug’s physical dimensions if you’re planning to use it behind furniture and need it to fit flush behind your couch.
• How do you want to use your smart plug? Not all smart plugs have energy-saving features or sunset/sunrise timers. Double-check that your smart plug’s features deliver what you’re looking for before purchasing.

A smart plug can optimize any appliance or device with an external on/off switch. Want to wake up as your coffee is brewing? Keep forgetting if you turned off your curling iron? Hate having to get out of bed to turn off the lights? The possibilities of smart plugs are endless. You can even use smart plugs outside—just make sure it is an outdoor plug with weather resistance.

Some of the most common and creative ways people use their smart plugs are to control lamps, ceiling fans, motion sensors, window AC units, teapots, and even dehumidifiers. I took a look at Reddit and found that some people even use smart plugs to automate aquariums, which often require intricate schedules for pumps and filters.

Here are some of the ways you can use a smart plug to make your life easier or just more fun:

• Power up your work desk before you get to work: In order to avoid having to wait for their computer to start in the morning, a customer used smart plugs to automatically turn their work equipment on as they pulled into the parking lot.
• Open and close your garage door remotely: Whether traveling or cozy in your bed, check that your garage is secure. And while on vacation, you could even turn off your garage door entirely just for peace of mind against code hackers.
• Schedule your air purifier: Set a schedule for your air purifier to turn on at night and turn off in the morning.
• Customize your Christmas lights: Set your Christmas lights on a sunset/sunrise timer, turning on as the sun sets and off as the sun rises. This tip applies for Halloween decorations too!
• Automate your garden fountain: By using a smart plug with a water feature in conjunction with a motion detector, you can schedule your fountain to turn on only when it senses motion in the garden. Your local flock of birds who bathe will thank you.
• Perform an efficiency test: Use a smart plug's energy monitoring feature to test your device’s efficiency, observing if a device’s standby power usage is at an acceptable range.

Speaking of power usage, ensure that your smart plug’s maximum wattage is compatible with the device you want to use it with.

Every smart plug has a maximum amount of electricity it can withstand. For example, the Amazon Smart Plug and the WeMo Smart Plug can withstand up to 1,800 watts, while the Kasa Smart Plug can support devices up to 1,500 watts.

You won’t need to worry about wattage capacity with typical appliances like TVs, coffee machines, and desktop computers. But you should avoid using smart plugs for larger devices like dishwashers or washing machines, as they will most likely exceed your plug’s voltage capacity.

Here are five of the most popular smart plugs. We've listed out which smart home ecosystems they are compatible with to help you find one that fits your needs. If you want to go deeper, here's our full guide on smart plugs.