Anonymous
Mar 26, 2026
Rating: 5/5
Great accuracy for the cost
I was surprised by how stable the readings were. Used it to build a liquid level monitor, and it has been running without issues for weeks.
Description
Reviews
| Brand | - |
| Category | Robotics / STEM Teaching Tools / Sensors |
| Origin | - |
| Operating Voltage | DC 5V |
| Static Current | < 2mA |
| Measuring Angle | 15 degrees |
| Measuring Range | 2cm - 400cm |
| Resolution | 0.3cm |
| Trigger Input Signal | 10µS TTL pulse |
| Echo Output Signal | TTL level signal proportional to distance |
| Dimensions | 45mm x 20mm x 15mm |
| Connector Type | 4-Pin Header (VCC, Trig, Echo, GND) |
| Compatibility | Arduino, Raspberry Pi, STM32, ESP8266 |
Anonymous
Mar 26, 2026
Rating: 5/5
Great accuracy for the cost
I was surprised by how stable the readings were. Used it to build a liquid level monitor, and it has been running without issues for weeks.
Anonymous
Mar 24, 2026
Rating: 4/5
Good sensor, needs calibration
Works well for obstacle avoidance robots. I noticed slight variations at very close ranges (under 3cm), but for general use, it is reliable. Easy to wire up.
Anonymous
Mar 22, 2026
Rating: 5/5
Perfect for Arduino Projects
This HC-SR04 module works flawlessly with my Arduino Uno. The distance readings are consistent and accurate within the specified range. Great value for the price.
Anonymous
Mar 21, 2026
Rating: 5/5
Essential for learning electronics
Bought this for a university project. The documentation online is plentiful, and the module itself is robust. It survived several accidental drops during testing.
Anonymous
Mar 10, 2026
Rating: 4/5
Solid performance
Does exactly what it says on the tin. The 5V requirement means you need a logic level converter if using with 3.3V boards, but that is standard for this model.
Anonymous
Mar 05, 2026
Rating: 5/5
Reliable and Affordable
We ordered ten of these for our workshop. All units performed identically. The response time is fast enough for real-time applications like parking sensors.
Q: What is the minimum detection distance?
A: The effective measuring range starts from approximately 2cm. Objects closer than 2cm may not be detected reliably or may return inconsistent values.
Q: Is there a library available for ESP32?
A: Yes, there are numerous open-source libraries available for the ESP32 platform, such as 'NewPing' or standard example codes found in the ESP32 community forums that support the HC-SR04 protocol.
Q: How do I handle multiple sensors on one microcontroller?
A: You can connect multiple modules by assigning separate Trigger and Echo pins for each sensor on your microcontroller. Ensure you trigger them sequentially rather than simultaneously to avoid acoustic interference between the sensors.
Q: Can this sensor be used directly with a 3.3V Raspberry Pi?
A: The HC-SR04 operates at 5V. While the trigger input often accepts 3.3V, the echo output returns 5V which can damage a Raspberry Pi GPIO pin. We recommend using a voltage divider or a logic level converter for the echo pin.
Q: Does this module come with jumper wires?
A: No, the package includes only the HC-SR04 ultrasonic module. Jumper wires are sold separately to allow you to choose the length and color you prefer for your specific setup.