Head-to-head · Best Water Leak Detectors

Eufy Water and Freeze Sensor vs Shelly Flood Gen4

Which is the better buy? Side-by-side on rating, price, strengths, and watch-outs — with the published ratings we averaged to get there.

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The short answer

Eufy Water and Freeze Sensor comes out ahead by a clear margin (4.5 vs 3.4). Eufy Water and Freeze Sensor is best for: Homes that already have a Eufy HomeBase, or owners worried about frozen pipes in crawlspaces and under sinks who are willing to buy one. Read the strengths below before deciding.

Higher ratedRanked #3 in Best Water Leak Detectors

Eufy Water and Freeze Sensor

4.5

1 sourceall derived$34.99as of Oct 20

The Eufy Water and Freeze Sensor senses both pooling water and freezing temperatures, which is why CNET's Tyler Lacoma, who has tested more than a dozen leak detectors, names it his best overall pick. He found it simple to set up, with a two-year replaceable battery and phone alerts wherever you are. The catch is that it only works through a Eufy HomeBase hub, which CNET says can cost around $100 or more.

Strengths

— Senses both water and freezing temperatures, the feature CNET says impressed it most
— Simple to set up, per CNET
— Two-year replaceable battery, per CNET

Watch-outs

— Requires a Eufy HomeBase hub; CNET puts the latest hubs at around $100 or more, a high ask for one leak detector

$34.99 · Check Price on Amazon Full review →

Ranked #6 in Best Water Leak Detectors

Shelly Flood Gen4

3.4

3 sources$39.99as of Oct 20

The Shelly Flood Gen4 is a smart water leak sensor designed for early detection of water leaks, sending real-time alerts to your phone and triggering a built-in alarm. It supports multiple protocols including Wi-Fi, Zigbee, Matter, and Bluetooth, and integrates with major smart home platforms like Alexa, Google Home, and Apple HomeKit. YouTube reviewer TecTimmy noted its effectiveness for early flood detection in coastal areas, while PCMag praised its expandable coverage capabilities. It's best suited for users seeking a budget-friendly, expandable leak detection solution, though it requires a smart home network for full functionality.

Strengths

— Detects water leaks in real-time and sends alerts to your phone
— Built-in alarm for immediate local notification of leaks
— Supports multiple smart home protocols including Wi-Fi, Zigbee, Matter, and Bluetooth

Watch-outs

— Requires Wi-Fi or Zigbee network for full functionality

$39.99 · Check Price on Amazon Full review →

Derived means the reviewer published no score, so one was inferred from their written verdict. Everything else is a number the publisher printed. How we rank.

How they stack up

Eufy Water and Freeze Sensor

Like the First Alert L1 and the Kidde Water Leak + Freeze Detector, the Eufy watches for freezing temperatures as well as water, but it needs a Eufy HomeBase hub where those two connect over Wi-Fi. CNET picks the SwitchBot Wi-Fi Leak Detector as its standalone, no-hub alternative.

Shelly Flood Gen4

The Shelly Flood Gen4 supports Wi-Fi, Zigbee, Matter and Bluetooth, where the First Alert L1 Wi-Fi Water Leak and Freeze Detector lists Wi-Fi and the Aqara Water Leak Sensor lists Zigbee. It has a built-in alarm, which the First Alert L1's entry says that model lacks, and its sensor cable can be extended up to 150m from the 2m supplied. Its IP44 rating is lower than the IP67 of the Aqara and the SwitchBot Wi-Fi Leak Detector.

Specs side-by-side

Spec	Eufy Water and Freeze Sensor	Shelly Flood Gen4
Power Source	Replaceable battery, 2-year life (per CNET)	Battery powered (battery included)
Sensors	Pooling water and temperature	—
Hub Required	Yes, Eufy HomeBase	—
Range	670 feet (per CNET)	—
Connectivity	—	Wi-Fi, Zigbee, Matter, Bluetooth
Alarm Type	—	Real-time phone alerts and built-in alarm
Detection Method	—	When water touches a sensor
Water Resistance	—	IP44
Sensor Type	—	Water leak detection
Dimensions	—	97x76x25 mm
Material	—	Plastic

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