Laundry Detergent Level Monitor Kit with Arduino Uno & Ultrasonic Sensor — Get Alerts Before Detergent Runs Out

Every part needed, pre-tested for compatibility, with an AI build companion trained on this exact project. Shipped from Bengaluru in 3-5 days.

Running out of detergent mid-laundry is a common frustration in busy Indian households and hostels. This kit transforms a standard detergent drum into a smart container that shows the remaining level as a percentage on an OLED display and sounds an alert when the detergent drops below 20%. You’ll build a reliable, battery-powered monitor using an Arduino Uno and an HC-SR04 ultrasonic sensor — no plumbing or modifications to the drum required.

What You'll Build

You’ll create a compact sensor unit that mounts under the detergent drum’s lid. The HC-SR04 fires ultrasonic pulses down toward the liquid surface and measures the echo time to calculate the remaining detergent volume. The OLED displays a clear percentage, and when the level falls below 20%, a loud active buzzer alerts anyone in the room. The whole system runs on a single 9V battery for quick deployment.

What You'll Learn

• Calibrating an HC-SR04 ultrasonic sensor to convert distance into liquid percentage
• Programming Arduino Uno to drive a 0.96-inch OLED display via I2C
• Implementing threshold-based alerts with an active buzzer
• Building and testing a breadboard prototype with 10kΩ pull-up resistors and filtering capacitors

Kit Contents

HC-SR04 in detergent drum measures remaining level. OLED shows percentage and alerts when below 20%.

What's in this kit

• Arduino Uno R3
• HC-SR04
• 0.96in OLED
• Active Buzzer
• 10kΩ Resistors x5
• 100nF Caps x5
• 400-pt Breadboard
• M-M Wires x20
• 9V Battery Snap