Description
Reviews
| Brand | - |
| Category | Robotics / STEM Teaching Tools / Sensors |
| Origin | - |
| Model Number | MQ-3 |
| Detection Target | Alcohol, Ethanol, Flammable Gases |
| Operating Voltage | 5V DC |
| Output Signal | Analog (AO) and Digital (DO) |
| Sensitivity Range | 0.04mg/L to 4mg/L (Alcohol) |
| Response Time | < 10 seconds |
| Recovery Time | < 30 seconds |
| Heater Voltage | 5.0V ± 0.2V |
| Load Resistance | Adjustable via Potentiometer |
| Interface Type | 3-Pin Header (VCC, GND, OUT) |
Anonymous
Mar 30, 2026
Rating: 4/5
Good value but needs calibration
The module is well-built and the digital output threshold is adjustable. Just remember it takes a few minutes to heat up before giving accurate readings. Solid choice for hobby projects.
Anonymous
Mar 27, 2026
Rating: 5/5
Reliable and easy to integrate
I've used several gas sensors, and this MQ-3 is one of the most consistent. The pinout is standard, making it easy to wire into existing PCBs. Highly recommended for students.
Anonymous
Mar 24, 2026
Rating: 5/5
Excellent sensitivity
Very impressed with how sensitive this probe is. Even small amounts of alcohol vapor trigger the digital output when calibrated correctly. Fast shipping too.
Anonymous
Mar 13, 2026
Rating: 3/5
Decent but requires warm-up
The sensor functions well once heated, but you must account for the 2-3 minute warm-up time in your code logic. Otherwise, initial readings are erratic. Good for the price.
Anonymous
Mar 13, 2026
Rating: 5/5
Perfect for my breathalyzer prototype
This sensor works exactly as described. I connected it to an Arduino and the analog readings were stable after the initial warm-up period. Great sensitivity for ethanol detection.
Anonymous
Mar 08, 2026
Rating: 4/5
Works well for alcohol detection
Successfully used this to detect hand sanitizer vapors in a smart dispenser project. It reacts quickly. The only downside is the power consumption due to the heating element.
Q: Can this detect methane or propane?
A: While the MQ-3 is optimized for alcohol and ethanol, it may show some reactivity to other flammable gases. However, for methane or propane, we recommend the MQ-4 or MQ-5 models for better accuracy.
Q: What is the current draw during operation?
A: The heater inside the sensor typically draws about 150mA to 200mA at 5V. Please ensure your microcontroller or power supply can handle this load.
Q: How long does the sensor last before needing replacement?
A: Under normal operating conditions, the MQ-3 sensor element typically has a lifespan of 1 to 2 years. Continuous exposure to very high concentrations of gas may reduce this lifespan.
Q: Is a library available for Arduino?
A: Yes, there are several open-source libraries available on the Arduino Library Manager specifically for MQ series sensors that simplify reading and calibration.
Q: Does this module output a simple high/low signal or an analog value?
A: It provides both. The DO pin gives a digital high/low signal based on your potentiometer setting, while the AO pin provides a variable analog voltage proportional to gas concentration.
Baby Wooden Rattle Toy - Chewable Traditional Goat Skin Shaker for Newborn Boys and Girls
$9.80
Yuanhengtong Whiteness Meter WSB-1/2Y/3Y/CY, Digital Whiteness Tester for Paper, Flour, Paint, Plastic, Ceramics, and Textiles
$1,055.80
G460 Fast-Drying Glue for Plastics Bonds PP PVC ABS PC PS Strong Low-Whitening Transparent Instant Adhesive
$38.80
Children's Drawing Board Blackboard Whiteboard Accessories Colorful Whiteboard Markers Chalk Set Magnetic Stickers Toys Letters Numbers Eraser
$3.00
Automatic Retractable Air Hose Reel - Pneumatic Hose Drum for Auto Repair, Detailing, and Water/Electric Applications
$295.00
Sheepskin Rattle Traditional Handmade Baby Safe to Chew Brass Stick Bell Clapper Rattle Intangible Cultural Heritage Leather Newborn
$16.00
Glass Reactor with Multi-Function Stirring and High-Temperature Resistance - Double-Layer Glass Reactor from Manufacturer, Customizable
$85.00
Charcoal Blending Stump Set for Sketching - Highlight, Shadow, and Detail Tools with Replaceable Sponge Tips for Artists
$4.80
Minimalist Stainless Steel Toothbrush Holder with Drainage - Ins Style Bathroom Organizer for Cosmetics
$10.40
Qili Automotive Paint Degreasing Cloth – Glue/Dust Removal Paper, Industrial Wiping & Absorbent Paper
$313.12
Qingzhu Sketch Blending Cotton - Professional Sponge Balls & Paper Stumps for Art Students, Colorful Thick Absorbent Drawing Tools
$4.38
Electric Scooter Dashboard Cover for Aima Metaverse PLAY Instrument Panel Screen Protector Waterproof Case
$13.50
Continental Tire 265/40R22 106V XL FR CSC5 SUV - Compatible with BYD Tang (Removed from Vehicle)
$618.00
Yandi Retainer Storage Case for Kids - Lightweight Portable Box for Orthodontic Aligners and Dentures
$8.42
Zhizhi Manshu Wen Zhengming Small Regular Script Collection of Twelve Ancient Texts: Yueyang Tower Record, Peach Blossom Spring Record, Farewell to Dongyang Ma Sheng Xu
$68.00
Factory Direct Rubber Molding Tools - Custom Production & Processing
$2,280.00
Catalytic Combustion Waste Gas Treatment Equipment - RCO Activated Carbon Adsorption and Desorption Integrated Machine for Industrial Exhaust Processing
$26,000.00
ASY Gravure Printing Machine for Plastic Film, 6-Color Flexographic Printer for Shopping Bags
$86,400.00
Coil Refractory Cement for Medium-Frequency Furnace Repair - Fine High-Temperature Bonding Agent for Copper Coils (White/Red)
$7,800.00
Over-Toilet Storage Rack - No-Drill Bathroom Organizer Shelf for Restrooms and Washrooms, Space-Saving Storage Solution
$8.90
NIU NXT Instrument Cover for FXT/FX Electric Scooters – Waterproof Protective Case and Modification Accessory
$6.50
Anlin FK1 Cheyenne Tattoo Pen Silent Model All-in-One for Lining and Shading
$221.25
![[Osstem Dental Implants] Imported Dental Crowns and Bridges by Aizhier Oral Care for Partial Tooth Loss](https://www.gosteppe.com/cache/small/product/269993/legacy-main-02952134e1556f7660e1525f.webp)
[Osstem Dental Implants] Imported Dental Crowns and Bridges by Aizhier Oral Care for Partial Tooth Loss
$230.00
Heavy-Duty Multi-Layer Warehouse Shelving Unit for Storage, Retail, and Home Use
$252.00
Rattle Car Teether Wooden Bead Educational Soothing Teething Set Baby Photo Prop
$15.00
Roast Duck and BBQ Warmer Cabinet - Constant Temperature Heating Display Case for Crispy Pork Belly and Hanging Ducks
$710.00
Traditional Handmade Baby Rattle with Chewable Sheepskin for Newborns
$12.50
5pcs Lily tubular length 7cm fish tank aquarium glass
$9.90
Data Cable Interface Safety Case for iPhone, Apple, and Android Charging Cables - Child and Pet Proof
$16.80
Commercial Roast Duck Warmer Cabinet Constant Temperature Food Heater Display Counter for Cooked Meat
$1,494.00
![[Youxin Electronics] GP2Y0E03 Infrared Distance Sensor Module 4-50cm Range](https://www.gosteppe.com/cache/medium/product/74667/legacy-main-4da8cadc5fc82afe91b124e3.webp)
![[Trial Pack] Xianlang Complete Cat Treat Sticks Meal Packs Main Course Cans Freeze-Dried Cat Food Sample Snacks Gift Set](https://www.gosteppe.com/cache/medium/product/208273/legacy-main-9ec245ebf781f65a434ba854.webp)
