Best door and window sensors

The Tapo T110 Smart Contact Sensor is an easy and affordable addition to your DIY security system or smart home. Priced at just $25, it packs some pretty impressive features.

Like most smart contact sensors, it does require a hub (either the $34 Tapo H100 or the Tapo H200, which comes with select Tapo cameras), but even so, it still winds up being one of the more affordable options out there—especially if you plan on buying multiple sensors or building out your smart home with other Tapo products like smart switches, plugs, and light bulbs. The hub can also act as a siren, which, when triggered, can deter potential intruders.

We really like how small, easy-to-install and user-friendly the Tapo T110 (and the Tapo app as a whole) is.

Plus, since it's compatible with Alexa and Google Assistant, you can simply ask your smart assistant of choice, "Is the garage door open?"

The HENDUN Wireless Door Alarm trades smart features for budget-friendly practicality. This security sensor doesn't come with an app or wireless abilities like the others in our lineup but cost only around $15 each when you buy a two-pack.

We recommend using this for off-limits areas like sheds and storage units or in areas that are dangerous or private. So while you'll miss out on app notifications, it won't be hard to hear if the blaring 120-decibel alarm sounds. Of course, if you want something easier on the ears, you can change the alarm to silent mode or chime. We think the door chime is a nice addition to busy homes so you can know when the kids head out.

Overall, we like HENDUN's simplicity for those that don't want a mobile app or smart home controls. It's even a great supplement to pricier smart sensors so you can place those on high-priority doors and windows while using these ones almost anywhere else.

The Eve Door & Window is one of the best ways to add a contact sensor to an Apple smart home. Its compatibility with HomeKit means you can control it with the Apple Home app without downloading any extra apps on your iPhone—you can also ask Siri to check the status.

While the Eve app isn't necessary to use these sensors, it's the only way to view statistics like time and duration of sensor activity since Apple Home doesn't track that information. You also need it to install the occasional firmware update. Still, Apple Home is the better option for using the sensor, thanks to its customisable notifications and rules for how the sensor interacts with another smart device.

On the downside, this sensor doesn't have an Android app—you must use an iOS device, and there's no siren on this unit (or even the option to add one). Also, because it's Bluetooth-powered, you need an Apple Home Hub like the HomePod Mini, Apple TV, or iPad at home if you want to check the sensor from anywhere, which adds to this sensor's already high price.