Attributes

Brand	-
Category	Robotics / STEM Teaching Tools / Sensors
Origin	-
Model Compatibility	MQ-2, MQ-131, MQ-3, MQ-4, MQ-5, MQ-6, MQ-7, MQ-8, MQ-9
Operating Voltage	5V DC
Output Signal	Digital Switch Output (0 and 1) & Analog Output
Detection Gases	LPG, Propane, Hydrogen, Alcohol, Smoke, CO, Methane
Sensitivity Adjustment	Adjustable via onboard potentiometer
Indicator LED	Power LED and Digital Switch Output LED
PCB Dimensions	32mm x 20mm x 15mm
Mounting Holes	4 x 3mm diameter holes for easy installation
Interface Type	3-pin header (VCC, GND, OUT) + Analog pin
Application Scope	Home safety alarms, industrial gas leak detectors, DIY electronics

6 reviews

Anonymous

Mar 27, 2026

Rating: 4/5

Good sensor, needs warm-up time

Works as described. Just remember these sensors need about 24-48 hours of initial burn-in to stabilize readings. After that, the alcohol detection on the MQ-3 module was quite accurate.

Anonymous

Mar 24, 2026

Rating: 4/5

Great for learning embedded systems

Used this for my university final year project. The dual output (analog and digital) makes it versatile for different coding approaches. Only wish the cables were included, but standard jumpers work fine.

Anonymous

Mar 23, 2026

Rating: 5/5

Excellent for combustible gas alerts

Using the MQ-6 for LPG detection in my kitchen prototype. It reacts fast to lighter fluid tests. The build quality of the PCB feels sturdy enough for enclosure mounting.

Anonymous

Mar 15, 2026

Rating: 5/5

Bulk buy for our workshop

Purchased several units for our community makerspace. All modules tested working out of the box. The MQ-131 ozone sensor variant is particularly interesting for outdoor monitoring projects.

Anonymous

Mar 14, 2026

Rating: 5/5

Perfect for my Arduino security project

I used the MQ-2 variant for a smoke detection prototype. The analog output is very responsive, and adjusting the sensitivity with the potentiometer was straightforward. Great value for the price.

Anonymous

Mar 13, 2026

Rating: 5/5

Reliable and easy to interface

Bought a mix of MQ-4 and MQ-7 for a custom air quality monitor. The digital output triggers cleanly when gas levels rise. Documentation online is plentiful which helped me get started quickly.

5 FAQ

Q: Can I detect multiple gases with one single module?

A: Each specific model (e.g., MQ-2, MQ-3) is optimized for a particular range of gases. For example, MQ-2 is best for smoke and LPG, while MQ-3 is for alcohol. To detect distinct gas types accurately, you would need to deploy the specific module designed for that gas.

Q: Does this module work with 3.3V microcontrollers like ESP32?

A: The sensor heating element requires 5V to operate correctly. While the logic output might work with 3.3V, we strongly recommend powering the VCC pin with 5V and using a voltage divider or level shifter for the signal pins if your MCU is strictly 3.3V tolerant.

Q: Is this sensor suitable for outdoor weather exposure?

A: No, this module is not waterproof or weather-resistant. It should be installed inside a protective enclosure with proper ventilation holes to allow gas entry while shielding the electronics from rain, dust, and direct sunlight.

Q: What is the difference between the DO and AO pins?

A: AO (Analog Output) provides a continuous voltage proportional to the gas concentration, allowing you to read exact levels via an ADC. DO (Digital Output) acts as a switch; it goes HIGH or LOW when the gas concentration exceeds the threshold set by the onboard potentiometer.

Q: How long does the sensor need to heat up before giving accurate readings?

A: For stable and accurate readings, the sensor typically requires a pre-heat time of about 24 to 48 hours upon first use. After the initial burn-in, a warm-up period of 1-2 minutes before each measurement cycle is usually sufficient.

Explore your interests

STC32G12K128 STC8H8K64U Microcontroller Small System Core Board Development Board Emulator

$16.50

Youxin Electronics_STM32H743IIT6 Core Board System Board Learning Board STM32 Development Board

$118.00

Arduino DUE Development Board 32-bit ARM Controller A000062 Italian Official Original Import with Cable

$299.00

Ultrasonic Sensor HC-SR04 Ultrasonic Distance Measuring Module Bracket US015-025-026-100

$3.16

Serial SHT20 Chip Temperature and Humidity Sensor Test, SHT30 Chip Measurement and Monitoring Module by Viter Intelligence

$11.00

High-Speed Yabo Smart Raspberry Pi 4B Motherboard Development Board Accessories RaspberryPi 2G/4G/8G RAM Py

$494.30

Magnetic Circular Counting Chips, Two-Sided Flip Coins for Elementary Math, Kindergarten Early Education, Ten-Frame Matrix, Addition/Subtraction within 10 & 20, Teaching Tools

$11.90

HC-SR501 Human Motion Infrared Sensor Module Compatible with Arduino micro:bit Eco-Friendly

$7.50

SANSI White Label Class A Glass Graduated Cylinder C18 Micro-Precision Demulsification Cylinder with Scale Measurement Includes Certificate Ground Joint Stopper Hexagonal Bottom Borosilicate Glass Lab Equipment

$3.68

EV2400 Battery Unlock Fuel Gauge Programmer MSP430 HPA500 Evaluation Module Interface Board SMBus

$323.00

Cube Three-View Teaching Aid with Grid - 3D Geometry Observation Tool for Grades 4-5 Math (2cm Cubic Blocks Set)

$15.10

OrangePi Orange Pi Zero3 Zero 3 Development Board Allwinner H618 Orange Pi

$228.00

Zave MAX30100 MAX30102 Module for Blood Oxygen, Wrist Heart Rate, Pulse, and Heartbeat Detection

$3.39

12V Stable Version Light-Control Switch No-Light Sensing with Extension Cable Photoresistor Plus Relay Module

$49.20

STM32 Smart Car 51 Microcontroller Arduino Obstacle Avoidance Chassis Kit Mecanum Wheel Robot Car

$40.80

Tech Small Production Small Invention DIY Piano Electronic Keyboard Real Playable Science Small Handmade DIY Materials

$33.00

[Youxin Electronics] GP2Y0E03 Infrared Distance Sensor Module 4-50cm Range

$23.65

Transparent 3D Geometric Model Perspective Decomposition Graphic Teaching Aid, Complete Set for Elementary Grades 1-6 Math

$6.80

DHT22 Single-Bus Digital Temperature & Humidity Sensor AM2302 Module Electronic Building Blocks

$10.42

E18-D80NK Infrared Photoelectric Switch Diffuse Reflection Obstacle Avoidance Sensor Module 3-80CM

$12.60

LAN8720 Module Network Module Ethernet Transceiver RMII Interface Development Board Xinwei Electronics

$7.85

STC15W408AS Core Board Minimum System Board 51 Microcontroller Development Board TTSOP20 Learning Board

$18.47

New Version MEGA2560 R3 Development Board, Improved MEGA2560 R3 with Sensor Expansion Board

$13.68

Gradient Visual Illusion Kit: Electric Rotating Assembly Toy for Maker DIY, Paintable Handmade Model

$8.72

51/AVR Microcontroller Core Development Board STC89C52RC/51MCU Experiment Board/ATMEGA32 Learning Board

$37.90

[Trial Pack] Xianlang Complete Cat Treat Sticks Meal Packs Main Course Cans Freeze-Dried Cat Food Sample Snacks Gift Set

$15.00

GY-30 302 Digital Light Intensity Illuminance Sensor BH1750FVI Module Light Sensor Ball

$7.41

Foldable Clothes Drying Rack Floor Standing Home Balcony Bedroom Hanging Clothes Quilt Drying Artifact Outdoor Cooling Rod Indoor Drying Rack

$47.10

Metal Detector Module Non-Contact Metal Induction Sensor Detection Module Metal Detector

$8.70

RV1103 Miniature Linux Development Board: RISC-V Vision and AI with Ethernet Port

$53.10

For Arduino Development Board R3 Mainboard Microcontroller Module Kit Programming Learning Board Sensor Suite

$78.00

Xuefen Geometry Stamping and Tracing Set for Grades 1-2, 3D and 2D Ink Pads, Math Learning Tools, Cube and Cuboid Models

$4.51

Rubber Tire Toy 4WD Smart Car Wheels Car Model Robot Accessories (Suitable for 2mm Axle)

$0.50

E18-D80NK Infrared Obstacle Avoidance Sensor Proximity Switch Smart Robot Car 10-80cm

$6.30

OPT3001/3002/3004 Ambient Light Sensor Module Measures Visible Light Density Digital Optical Sensor

$8.14

51 MCU Minimum System STC89C52 DIP40 Through-Hole Smart Car Main Control Board Learning Experiment

$19.80

Outdoor Adventure Kids' Insect Observation Box with Magnifying Glass, Boys & Girls Toy for Exploration, Butterfly Catching and Fish Scooping Tools

$7.80

Risym Laser Head Sensor Module Suitable for Laser Module Expansion Board Laser Sensor Development Board

$2.82

Freeze-Dried Chicken Treats for Dogs: Nutritious Weight-Gain Breast Meat Chunks for Puppies – Teeth Cleaning, Grain Mixing, Universal Use

$3.90

Soil Moisture Sensor Probe Soil Moisture Meter Detection Module Sensor Separate Probe

$2.39