Best Driveway Sensors and Alarms of 2021

Whether you have a long winding driveway or a short road leading to your garage, driveway sensors—like our top pick, Guardline—are a smart way to monitor vehicles entering and exiting your property. These devices are easy to install and fit a range of budgets for long and short driveways.

Take a look through the different sensors and their effective ranges, and think about the geographic features around your home. Heavy foliage and hills may reduce those ranges, so figure out which sensor would work best for your home—and never be surprised by a visitor again.

The Guardline allows for a quarter mile between the sensor and the receiver, although heavy foliage and thick walls will reduce this distance. The sensors can withstand all types of weather and work without interference, and the receivers come with a battery backup as well as a 12-volt relay to link them to additional external alarms.

Guardline claims two years of testing went into each product, and the reviews seem to back that up. With over 1,000 reviews on Amazon, the Guardline earns consistently high ratings—an impressive track record, no matter the product.

The base system comes with a single sensor and receiver. You can add up to three more sensors later, but you must purchase them separately. When someone (or something) breaks the sensor’s line, the receiver sets off an alert with both light and sound.

The sensor detects motion up to 30 feet in front of it and will reach a receiver up to a half-mile away. However, it needs line of sight to function properly. The receiver uses AA batteries or an AC adapter, allowing you to carry it with you into the yard.

The unit is composed of a sensor and a receiver that sends out a sound when triggered. The unit is small and unobtrusive, and runs on two AA batteries. The receiver has no battery backup and relies on a 12-volt power supply to operate. The receiver also has an LED display that shows how many times the sensor has been activated.

The downside to this device is the cost. The Rodann starts around $100, but for so few features it seems the price should be lower. The unit has solid reviews from its customers, but there are other less-expensive options that provide far more features and reliability.

The sensor can be as far as 1,000 feet from the receiver, but it has a maximum detection range of only 12 feet. What this sensor does right is ignore shadows, animals, and people.

The driveway monitor will be triggered, in theory, only by passing cars. It uses a magnetic sensor to detect passing vehicles, and the sensor itself is solar powered—so there’s no need to change batteries in it. However, the cost is a bit steep at around $150.

Even though Guardline is one of the more expensive driveway sensors on our list, it includes a lot of thoughtful features like unique alarm tones, a long receiver range, and support for up to 16 sensors.

When paired with other outdoor security equipment like security lights, outdoor cameras, and other motion sensors, driveway sensors can keep you aware of what's happening at your home whether you're there or not.

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