Anonymous
Mar 31, 2026
Rating: 4/5
Reliable detection
Used this in a prototype for a kitchen gas leak detector. It responds quickly to lighter fluid vapors. Note that this is a sensor module for development, not a certified standalone safety device.
Description
Reviews
| Brand | - |
| Category | Robotics / STEM Teaching Tools / Sensors |
| Origin | - |
| Model Number | MQ-2 |
| Detection Gases | LPG, Propane, Hydrogen, Methane, Smoke |
| Operating Voltage | 5V DC |
| Output Signal | Digital Switch Output (0 and 1) & Analog Output |
| Preheat Time | 24 Hours (Recommended) |
| Sensitivity Adjustment | Potentiometer included for threshold tuning |
| Interface Type | 3-Pin Header (VCC, GND, DO/AO) |
| Compatible Boards | Arduino, Raspberry Pi, STM32, ESP8266 |
| Dimensions | 32mm x 20mm x 15mm |
| Mounting Holes | 4 x 3mm diameter holes for secure installation |
Anonymous
Mar 31, 2026
Rating: 4/5
Reliable detection
Used this in a prototype for a kitchen gas leak detector. It responds quickly to lighter fluid vapors. Note that this is a sensor module for development, not a certified standalone safety device.
Anonymous
Mar 21, 2026
Rating: 5/5
Excellent sensitivity range
The dual output (analog and digital) is very useful. I used the analog pin to graph gas levels over time and the digital pin to trigger a buzzer alarm. Works flawlessly with 5V logic.
Anonymous
Mar 16, 2026
Rating: 4/5
Good value but needs warm-up
Great little module for the price. Just remember that it needs a significant warm-up period before the readings stabilize. Once heated up, the sensitivity is quite good for educational purposes.
Anonymous
Mar 14, 2026
Rating: 5/5
Perfect for my home safety project
This sensor works exactly as described. I connected it to an Arduino Uno and had it detecting simulated smoke within minutes. The analog output allows for precise reading of gas concentration levels.
Anonymous
Mar 09, 2026
Rating: 5/5
Easy to integrate
I was worried about the wiring, but the pins are clearly labeled. The potentiometer makes it very easy to adjust the sensitivity threshold for the digital output pin. Highly recommended for beginners.
Anonymous
Mar 04, 2026
Rating: 3/5
Works well after calibration
Took some trial and error to get the calibration right for our specific environment, but once set, it performs consistently. Make sure you have a clean power supply to avoid noise in the analog reading.
Q: How long does the sensor last?
A: Under normal operating conditions, the sensing element typically has a lifespan of 1 to 2 years. Continuous exposure to high concentrations of corrosive gases may reduce this lifespan.
Q: Is the library available for Arduino IDE?
A: Yes, there are several open-source libraries available in the Arduino Library Manager. Simply search for 'MQ2' or 'Gas Sensor' to find compatible code examples for reading analog and digital values.
Q: Does this work with 3.3V microcontrollers like ESP32?
A: Yes, but with caution. The heater requires 5V for optimal performance. You can power the VCC with 5V and use a voltage divider on the signal output if your microcontroller GPIO is strictly 3.3V tolerant, or use a logic level shifter.
Q: Why is the LED on the module always on?
A: The power LED indicates the module is receiving electricity. The second LED is the digital output indicator; it lights up when the gas concentration exceeds the threshold you set with the potentiometer.
Q: Can this sensor detect carbon monoxide?
A: The MQ-2 is primarily designed for LPG, propane, hydrogen, methane, and smoke. For Carbon Monoxide detection, we recommend the MQ-7 sensor model which is optimized for CO.