Description
Reviews
| Brand | - |
| Category | Robotics / STEM Teaching Tools / Sensors |
| Origin | - |
| Model Number | MQ-135 |
| Detection Gases | Ammonia, NOx, Alcohol, Benzene, Smoke, CO2 |
| Operating Voltage | 5V DC |
| Interface Type | Analog and Digital Output |
| Preheat Time | 24-48 Hours |
| Load Resistance | 20k Ohm (Adjustable) |
| Heater Resistance | 33 Ohm +/- 5% |
| Heater Consumption | < 800mW |
| Sensing Range | 10-1000 ppm |
| Board Dimensions | 32mm x 20mm x 14mm |
Anonymous
Mar 31, 2026
Rating: 4/5
Good value but needs calibration
Great little module for the price. The digital output threshold is adjustable via the potentiometer which is handy. It took some trial and error to get the baseline right for my specific room, but once set, it's reliable.
Anonymous
Mar 29, 2026
Rating: 5/5
Excellent for university projects
Bought this for my final year project on smart home safety. It detects smoke and alcohol vapors effectively. The documentation online is plentiful, making integration easy even for beginners.
Anonymous
Mar 28, 2026
Rating: 5/5
Perfect for Air Quality Projects
This sensor works exactly as described. I used it with an Arduino to monitor indoor air quality, and the analog readings are very responsive to changes in the environment. Just remember to let it preheat for a day before calibrating.
Anonymous
Mar 25, 2026
Rating: 3/5
Sensitive but drifts over time
It is very sensitive to ammonia and fertilizers which is what I needed. However, I noticed the baseline drifts after a few weeks, requiring recalibration. Good for prototyping, maybe not for long-term unattended deployment without maintenance.
Anonymous
Mar 05, 2026
Rating: 4/5
Solid sensor module
Does the job for detecting combustible gases and general air pollutants. The heater gets quite warm, which is normal for this type of sensor. Ensure your power supply can handle the current draw.
Anonymous
Mar 01, 2026
Rating: 5/5
Fast shipping and works great
Arrived well-packaged. Connected it to my Raspberry Pi via an ADC converter. It picks up on cooking fumes immediately. The build quality of the PCB looks solid with clear soldering points.
Q: Does this come with a library for Arduino?
A: We do not provide a proprietary library, but there are many open-source libraries available in the Arduino Library Manager compatible with MQ sensors. They make reading the analog values and converting them to ppm estimates very easy.
Q: How long does the preheating process actually take?
A: For stable and accurate readings, we recommend a preheating period of 24 to 48 hours. During this time, the sensor element stabilizes. You might see fluctuating values if you try to use it immediately out of the box.
Q: Can I power this with 3.3V instead of 5V?
A: No, the heater element requires 5V to reach the correct operating temperature for the chemical reaction to occur. Powering it with 3.3V will result in poor sensitivity or no detection at all. Use a 5V supply.
Q: Is the digital output pin HIGH or LOW when gas is detected?
A: By default, the digital output goes LOW when the gas concentration exceeds the threshold set by the potentiometer. However, this logic can often be inverted depending on how you interface it with your microcontroller code.
Q: Can this sensor detect natural gas leaks specifically?
A: The MQ-135 is primarily designed for ammonia, NOx, alcohol, benzene, smoke, and CO2. While it may react to some combustible gases, for dedicated natural gas (methane) detection, the MQ-5 or MQ-6 models are more appropriate and accurate.
Multi-Color Detachable Water Bucket Stand - Office Purified Water Dispenser Holder (Inverted)
$60.95
Oil-Based Original Strong Fast-Drying Adhesive for Metal, Plastic, Rubber, Ceramics, and Wood, Multi-Purpose Transparent Glue (Not 502)
$21.60
Jay Chou - Feng BROTHER_CHAO Piano Accompaniment Sheet Music
$50.00
Toplip Automatic Retractable Air Hose Reel, Water Drum, High-Pressure Foam Drum for Pneumatic Tools and Auto Repair
$118.00
500L Yogurt Production Line - Stand-Up Pouch Filling Machine with Complete Dairy Processing Equipment and Fermentation Tank
$13,720.00
5A Grade Uruguay Natural Deep Purple Amethyst Loose Beads DIY Crystal Accessories Amethyst Loose Round Beads Semi-Finished
$1.20
Car Vacuum Cleaner - High Suction, Compact, Silent, and High-Power
$68.89
Fifty Seven-Character Quatrains in Wang Xizhi's Running Script Calligraphy
$67.00
Food-Grade Square Retainer Storage Case for Orthodontic Aligners and Dentures
$6.72
365-Day Electric Guitarist Training Plan by Toshiro Miyako – Rock Electric Guitar Chinese Tutorial
$53.00
Portable Invisible Aligner Case - Compact Breathable Box for Orthodontic Retainers, Dentures, and Cleaning Storage
$18.80
Makeup Room Shelf Triangle Bathroom Corner Storage Rack No-Drill Wall-Mounted Vanity Organizer
$23.82
Stainless Steel Sink Organizer for Sponges and Steel Wool - Drill-Free Dishwashing Pad Rack with Drainage
$9.50
Monet Detail Watercolor Brush Set - Goat Hair Liner, Round Wolf Hair, Flat Oil Painting and Gouache Brushes
$76.00
365-Day Electric Guitarist Development Plan Beginner Introductory Electric Guitar Textbook Self-Study Tutorial Basic Skills Practice
$28.90
Over-Toilet Storage Rack for Bathroom - Multi-Functional No-Drill Organizer
$14.70
Wuxi 3D Five-Axis CNC High-Pressure Waterjet Cutting Machine for Metal, Glass, and Stone Inlay Patterns
$431,980.00
Zodiac Dragon & Snake Rattle Toy for Babies, Sheepskin Drum Head, Solid Wood, Non-Toxic, Chewable, Sensory Grasping Toy for 6+ Months
$14.80
Menghu Custom Plush Squeaky Keychain with Custom Voice - DIY Anime Comic Fabric Mini Pillow Charm
$12.80
Hell Jazz Drumming: Ultimate Drum Skill Training Institute - Complete Rock Drum Kit Manual and Tutorial for Drummers
$58.00
Custom Calligraphy Felt Mat for Chinese Painting and Brush Writing – Wool Felt Desk Pad or Wall Mat for Four Treasures of the Study
$9,022.00
Mini Watercolor Paint Notebook – Compact, Portable, Thickened Sketchbook for Markers, Ideal for Students and Casual Drawing
$7.58
Manufacturer Sales 35-Piece Automotive Repair Tool Set, 1/2" Pneumatic Socket Set, Extended Impact Sockets
$165.00
Portable Invisible Aligner Case for Invisalign and Children's Orthodontic Retainers
$12.50
Paper Blending Stumps Set for Art Highlighting and Sketching, Professional Smudging Tools for Fine Arts Students
$2.65
Sketch Blending Stump and Knife Set - Art Supplies Including Paper Stumps, Makeup Sponges, Highlight Detail Tools, Charcoal Wipers, and Scraper Kit
$4.08
New Children's Potty Training Seat for Boys and Girls
$28.00
FRP Spray Purification Tower for Thermal Power Plant Exhaust Gas Treatment - Desulfurization, Denitrification, Acid Mist Scrubber, FRP Chimney
$680.00
Handmade Natural Gourd Cute Smiley Face Rattle Baby Soothing Toy Safe for Chewing No Paint
$32.30
Baby Wooden Rattle Toy - Chewable Traditional Goat Skin Shaker for Newborn Boys and Girls
$9.80
![[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)
