Ultrasonic Sensor Module HC-SR04

Overview

The classic ultrasonic distance sensor — measures distance by timing an ultrasonic pulse's echo, the basis for a huge range of DIY distance-sensing projects.

Key Specs

Pinout

Features

• Simple 2-pin digital interface, no analog reading needed
• Extremely well documented, the standard distance sensor across most Arduino tutorials

Compatible With

Arduino, ESP32, ESP8266, Raspberry Pi

Use Cases

• Obstacle avoidance for robots
• Parking-assist and distance-alert projects
• Liquid-level and tank monitoring

FAQ

How does it calculate distance? It times how long the ultrasonic pulse takes to bounce back, then converts that time to distance using the speed of sound.