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  • Switchbot Water Leak Detector (Sensor Cable Edition)
  • Water Leak Detector (Sensor Cable Edition)
  • Water Leak Detector (Sensor Cable Edition)
  • Water Leak Detector (Sensor Cable Edition)
  • Water Leak Detector (Sensor Cable Edition)
  • Water Leak Detector (Sensor Cable Edition)
  • Water Leak Detector (Sensor Cable Edition)
  • Water Leak Detector (Sensor Cable Edition)
  • Water Leak Detector (Sensor Cable Edition)
Last updated July 2026

Switchbot Water Leak Detector (Sensor Cable Edition)

4.3
1,663 ratings
Launch Year: 2024

Model: W4402000

25% OFF
$19.99
$14.99
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Our review

SwitchBot Water Leak Detector (Sensor Cable Edition) Review: Four-Point Leak Coverage Without a Hub

A hub-free WiFi sensor with an extendable cable that covers two spots at once, though the battery hatch is a common complaint.

The verdict

The SwitchBot Water Leak Detector (Sensor Cable Edition) is a WiFi leak sensor that needs no separate hub, connects straight to your home network, and works with Alexa, Google Home, Apple HomeKit and SmartThings out of the box. Its extendable sensor cable lets one unit watch two spots at once, the main body and the cable tip, which buyers use to cover both a drip tray and an external leak point or to fit the probe into tight spaces like a water heater pan. It is consistently praised for sensitivity and quick alerts, though a batch of buyers single out the battery compartment as needlessly hard to open and a few found the onboard 100dB alarm quieter in practice than expected, especially through cabinet doors. For hub-free, multi-point leak monitoring across several major smart home platforms, it remains a strong value pick.

Best for
  • Buyers who want WiFi setup without a separate hub
  • Covering two leak points with one sensor via the cable
  • Water heaters, sump pumps and under-sink monitoring
  • Alexa, Google Home, HomeKit or SmartThings households

Pros

  • No separate hub needed, connects directly to WiFi
  • Extendable sensor cable adds a second detection point
  • Fast, sensitive water detection reported by buyers
  • Works with Alexa, Google Home, Apple HomeKit and SmartThings
  • IP67 water-resistant housing
  • Runs on easy-to-replace AAA batteries

Cons

  • Battery compartment can be stiff to open, included pry tool often breaks
  • On-device alarm can be hard to hear through doors or from other rooms for some buyers
  • No built-in temperature or freeze-alert sensor
  • No Matter support
  • App experience felt cluttered to a few reviewers

Who is the SwitchBot Water Leak Detector for?

This sensor suits buyers who want a leak detector that works straight out of the box on WiFi, no separate hub required, and who want broad smart home compatibility across Alexa, Google Home, Apple HomeKit and Samsung SmartThings. The included 2x AAA battery power and IP67-rated housing make it suitable for damp spots like under sinks, water heater pans, sump pump pits, and boat bilges. The extendable sensor cable is the standout feature: it adds two more detection points at the cable's tip, so one unit can watch both a drip tray and a nearby floor spot, or reach into a tight gap the main body can't fit.

What buyers love

Buyers consistently describe the sensor as fast and sensitive, several say it triggers within seconds of contact with even a small amount of water, and a few specifically compare it favorably to pricier hub-based leak detectors. The no-hub WiFi setup is a recurring highlight, since it connects directly to the app and home WiFi in minutes without extra hardware. The sensor cable also earns praise for its flexibility, buyers use it to monitor two locations with a single unit, or route the thin cable tip into confined spaces like inside a water heater pan where the main body wouldn't fit.

What to know before you buy

The most frequent complaint is the battery compartment: multiple buyers describe it as unusually stiff to open, with the included plastic pry tool bending or breaking before the hatch comes loose. A smaller group of buyers found the onboard 100dB alarm less audible than expected in practice, particularly through cabinet doors or from another room, meaning the phone notification becomes the primary alert in those placements. A couple of reviewers also described the companion app as cluttered with prompts on first setup. The sensor does not include a built-in temperature sensor, so it can't double as a freeze-warning device, and it lacks Matter support, relying on native integrations with each platform instead.

Is the SwitchBot Water Leak Detector worth it?

For its price, this sensor covers a lot of ground: hub-free WiFi setup, broad smart home integration, a genuinely sensitive detection element, and the flexibility of an extendable cable that turns one unit into two-point coverage. The battery-hatch friction and occasional alarm-volume complaints are real but minor next to the core job of catching a leak early, and buyers who plan carefully for its placement (within WiFi and phone-notification range) tend to be highly satisfied.

Frequently asked questions

Does the SwitchBot Water Leak Detector need a hub?

No, it connects directly to 2.4GHz WiFi, so no separate SwitchBot hub is required for basic leak alerts.

What does the sensor cable do?

The included extendable sensor cable adds detection points at its tip in addition to the main body, letting one device monitor two separate spots, such as a drip tray and a nearby floor area.

Does it work with Alexa, Google Home and Apple HomeKit?

Yes, it integrates with Alexa, Google Home, Apple HomeKit and Samsung SmartThings. It does not support Matter.

How loud is the built-in alarm?

It has a 100dB on-device alert sound and light. Most buyers find it effective at close range, though a few report it's harder to hear through cabinet doors or from other rooms, making the phone notification the more reliable alert in those spots.

What batteries does it use?

It runs on 2x AAA batteries with a manufacturer-rated battery life of about 2 years, though several buyers note the battery compartment can be difficult to open.

Does it monitor temperature too?

No, this sensor is dedicated to water-leak detection and does not include a temperature sensor or freeze alerts.

At a glance

Summary

Everything this water leak sensor supports, grouped by category.

Size & Materials
Weather Resistance (IP67)1.1 × 1.3 × 3.1 in (29 × 32 × 78 mm)3.8 oz (109 g)
Included accessories
Sensor Cable
Connectivity
2.4 GHz WiFiBluetooth
Integrations
Google HomeAlexaApple HomeKitSamsung SmartThingsHome AssistantIFTTT
Sensors
Water Leak
Alerts
Water Leak Alerts
Features
On Device Alert SoundOn Device Alert Light

Price History

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Company
SwitchBot logo

SwitchBot

4.2/ 5 avg ratingHong Kong flagHeadquartered in Hong Kong

SwitchBot makes a versatile range of smart home gadgets, most famously the SwitchBot Bot that physically presses existing buttons and switches. Its catalog includes curtain robots, smart locks, sensors, plugs and the SwitchBot Hub, which adds IR control and Matter compatibility. SwitchBot is popular for making non-smart devices smart without rewiring.

Full specifications

Every spec, organized

Browse the full breakdown by category. Tap the on any row for what it means, or the for sources and documentation.

Size & Materials

Weather Resistance

IP67

Dimensions

1.1 × 1.3 × 3.1 in (29 × 32 × 78 mm)

Weight

3.8 oz (109 g)

Included accessories

Sensor Cable

YES

Power

Wired

NO

Battery Type

2x AAA

Battery Life

2 years

Connectivity

2.4 GHz WiFi

YES

5 GHz WiFi

NO

Bluetooth

YES

Z-Wave

NO

Zigbee

NO

Thread Protocol

NO

Other

NO

Integrations

Google Home

YES

Alexa

YES

Apple HomeKit

YES

Samsung SmartThings

YES

Home Assistant

YES

IFTTT

YES

Matter

NO

Sensors

Water Leak

YES

Temperature

NO

Tilt

NO

Alerts

Water Leak Alerts

YES

Temperature Alerts

NO

Freeze Temperature Alerts

NO

Low Battery Alerts

?

Tamper Alerts

NO

Features

On Device Alert Sound

YES

100dB

On Device Alert Light

YES

Automations

YES

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