← All parts

HC-SR04 Ultrasonic Distance Sensor

Sensor

Ultrasonic sensor that sends out a 40 kHz sound wave and measures distance from the time its echo takes to come back. The core part of obstacle detection, parking sensor and level measuring projects.

Specifications

Measuring range

2 - 400 cm

Resolution

~3 mm

Measuring angle

15°

Operating frequency

40 kHz

Supply voltage

5V DC

Operating current

15 mA

Trigger signal

10 µs TTL pulse

Pins

VCC, TRIG, ECHO, GND

Size

45 x 20 x 15 mm

Shop prices

• F1 DepoIn stock40.20 ₺
• HobiDevreIn stock43.20 ₺
• RobotzadeIn stock45.00 ₺
• RobocomboIn stock45.00 ₺
• ElektrovadiIn stock45.09 ₺
• SAMM MarketIn stock49.61 ₺
• Modül ElektronikIn stock50.70 ₺
• HatfonIn stock52.06 ₺
• Robo90In stock53.57 ₺
• Robolink MarketIn stock54.00 ₺
• MotorobitIn stock58.08 ₺
• RobotsepetiIn stock60.96 ₺
• Direnc.netIn stock69.74 ₺
• KomponentciIn stock81.77 ₺
• Entegre DünyasıIn stock107.30 ₺
• RobitshopOut of stockPrice at the shop

Prices read from the shops' pages on 22 October 2026. Prices and stock may have changed since; check at the shop before you buy.

Projects with this part

• HC-SR04 Ultrasonic Distance MeterBeginner20 minA project that measures the distance to the object in front of an HC-SR04 ultrasonic sensor in centimetres and writes it to the Serial Monitor about 10 times a second. The sensor measures how long the echo of its sound wave takes to come back; the code turns that time into centimetres by dividing it by 58. No extra library needed.Open project
• Parking SensorIntermediate45 minLike the parking sensor in a car: the HC-SR04 measures the distance to whatever is in front of it, the buzzer starts beeping once something comes within 1 metre and the beeps get faster as it comes closer; below 10 cm the tone is steady. Green, yellow and red LEDs show the far, middle and near zones, and the distance is written to the Serial Monitor. It teaches timing with millis() instead of delay, so measuring, beeping and the lights run without waiting for each other, writing a function that returns a value, splitting into zones with if / else if, and turning the distance into a beep gap with map. No extra library needed.Open project
• OLED Distance MeterIntermediate40 minA meter that shows the distance measured by an HC-SR04 on a 0.96" OLED screen, no computer needed: the distance in large text on top, and below it a bar graph of the last 128 readings scrolling to the right. Move your hand closer and further and watch the graph rise and fall. It teaches driving a screen over I2C, drawing text and lines with Adafruit GFX, keeping readings in a ring buffer, and timing with millis() instead of delay. Install the "Adafruit SSD1306" and "Adafruit GFX" libraries from the Library Manager.Open project