Anonymous
Apr 16, 2026
Rating: 5/5
Great for Arduino Projects
Works perfectly with my Uno board. Calibration took some time but the analog reading is stable.
Description
Reviews
| Brand | - |
| Category | Electronic Components / Maker DIY / Computer Hardware, Monitors & Peripherals |
| Origin | - |
| Sensor Model | MQ-3 |
| Detection Target | Alcohol Vapor / Ethanol |
| Operating Voltage | 5V DC |
| Digital Output | TTL Logic (0 or 1) |
| Analog Output | 0-5V |
| Heating Voltage | 5.0V ± 0.2V |
| Circuit Voltage | 5.0V ± 0.2V |
| Load Resistance | 200KΩ |
| Operating Temperature | -10°C to 50°C |
| PCB Dimensions | 32mm x 20mm x 14mm |
Anonymous
Apr 16, 2026
Rating: 5/5
Great for Arduino Projects
Works perfectly with my Uno board. Calibration took some time but the analog reading is stable.
Anonymous
Feb 28, 2026
Rating: 4/5
Good sensitivity
Detects alcohol vapor well. Note that it needs a warm-up period before readings are accurate.
Anonymous
Feb 09, 2026
Rating: 5/5
Easy to use
Plug and play with the comparator module. LED indicator is helpful for debugging.
Anonymous
Feb 07, 2026
Rating: 5/5
Fast shipping
Arrived well packaged. Sensor responds quickly to changes in air quality.
Anonymous
Jan 21, 2026
Rating: 4/5
Solid component
Used this for a science fair project. Just remember it's not medical grade, but good for detection.
Q: Can this detect methane?
A: No, the MQ-3 is specifically sensitive to alcohol. Please check MQ-4 for methane.
Q: How long is the warm-up time?
A: We recommend a preheat time of 24 hours for stable long-term use, but initial readings appear after 2-3 minutes.
Q: What is the pinout?
A: VCC, GND, DO (Digital Out), and AO (Analog Out). Please refer to the diagram in the description.
Q: Is there a library for this?
A: Yes, many generic MQ sensor libraries work with the analog output pin.
Q: Does this work with 3.3V logic?
A: The module operates at 5V. For 3.3V systems, a logic level converter is recommended.