Video doorbells are one of the biggest purchases in a smart home, so it's important to ask questions before deciding which one to buy. But what are the factors to consider? Here are eight things to know when buying a video doorbell.

When replacing an existing wired push-button doorbell with a video doorbell, there are many options. Since the majority of both traditional and video doorbells are powered by a 24-volt transformer, in most cases the new video doorbell simply needs to be connected to the existing wiring.

However, if you do not have an existing doorbell, you will need to install wiring where you want to install the new doorbell or purchase a video doorbell that operates only on batteries. There are few models that operate solely on batteries, with Arlo and Ring producing the best models.

You see, that thing that goes "ding" when someone presses the doorbell. If there is a doorbell, there must be a chime, either mechanical or digital. A mechanical chime uses a hammer to strike a metal plate, while a digital chime emits an electronic sound from a speaker. [If you do not have a chime, you will need to purchase one that is compatible with the video doorbell you are buying; both Arlo and Ring sell plug-in digital chimes that work with video doorbells. These chimes are also useful when it is difficult to hear the doorbell from certain areas of the house.

The aspect ratio of a video doorbell is an important aspect of what can and cannot be seen through the front door. Originally, most video doorbells used commercially available cameras, which, like conventional cameras, have a wide aspect ratio but do not show much in the vertical direction. This means that if someone places a package right next to the front door, it will not be in view. Here is a look at the major video doorbell cameras and their aspect ratios: the closer to a 1:1 ratio, the more of the front door is generally shown, but no single video doorbell camera shows everything.

Since many of us receive many packages, it is important to know that a package has been placed at the front door. Some video doorbells have built-in AI that can recognize the shape of the box and send an alert if the box has been dropped off. Currently, the Nest Hello and Arlo video doorbells have this feature, and later this year, all video doorbells that use HomeKit Secure Video (such as the Logitech Circle View Doorbell) will add this feature.

The Nest Hello and Logitech Circle View Doorbell are linked to Google and Apple accounts, respectively, so they can match faces in the Google Photos and Apple Photos libraries to people approaching the door and announce their names with The system can then announce the name of the person approaching the door. Not an essential feature, but kind of handy.

One fun feature of many video doorbells is the ability to see what the doorbell sees on a smart display or smart TV. Some even allow you to interact with the person at the door.

All Ring video doorbells work with Amazon smart displays, including Echo Show 10, Echo Show 8, and Echo Show 5. If you have a Fire TV stick, Fire TV Cube, or Fire TV, you can also view Ring's video doorbell.

Similarly, if you have Nest Hello, you can view it on a Google smart display or Chromecast-compatible TV. In addition, feeds from HomeKit-compatible video doorbells, such as the Logitech Circle View, can be viewed on an Apple TV.

Arlo video doorbells work with both Alexa and Google-enabled devices, so you get the best of both worlds.

Sadly, most of the best video doorbells require you to purchase a subscription if you want to use all the features. If you do not subscribe, you can still use all of this, but the most you can do is display live video and respond to people at the door. You cannot save video, enable advanced features such as package detection, or create custom motion detection zones. Plans typically start at about $3 per month for a single device. For a more detailed look at what each company offers, check out our article on comparing security camera storage plans.

If you are considering purchasing additional home security cameras, it makes sense to choose a video doorbell from the same company. That way you won't have to pay for multiple subscriptions. Many subscriptions cover multiple cameras in a particular location, so it is a good idea to evaluate all of your potential security needs before deciding on a video doorbell.