Winsen
Winsen MH-Z19C Module
$25
Winsen MH-Z19C Module Overview
The Winsen MH-Z19C Module is a budget CO2 monitor that tracks CO2. It uses a NDIR sensor — the technology we recommend for reliable CO2 readings — with a stated accuracy of ±50 ppm across a 400-5000 ppm measurement range. At $25, it is aimed at DIY projects and budget-conscious buyers.
In day-to-day use, the MH-Z19C Module offers no built-in display — readings are accessed through a connected app or dashboard, plus UART and PWM connectivity for logging trends and setting alerts, plus a stationary design (N/A (module)) best suited to continuous monitoring in a fixed location.
Best For
Full Specifications
| Price | $25 |
| Sensors | CO2 |
| Sensor Type | NDIR |
| Connectivity | UART, PWM |
| Display | No |
| Portable | No |
| Battery Life | N/A (module) |
| CO2 Accuracy | ±50 ppm |
| CO2 Range | 400-5000 ppm |
Pros & Cons
Pros
- ✓True NDIR CO2 sensor (not an eCO2 estimate)
- ✓Accessible price point for a real CO2 sensor
Cons
- ✗No onboard display — requires the app to check readings
- ✗No wireless connectivity for logging or alerts
- ✗Not designed for portable use
Compare this monitor with others using our Monitor Comparison Tool
Frequently Asked Questions
Is the Winsen MH-Z19C Module accurate?+
The Winsen MH-Z19C Module uses a NDIR sensor with a stated accuracy of ±50 ppm over a range of 400-5000 ppm. NDIR is the proven reference technology for consumer CO2 monitoring.
What does the Winsen MH-Z19C Module measure?+
It measures CO2. CO2 is the key metric for judging ventilation — levels below 800 ppm indicate well-ventilated air.
Does the Winsen MH-Z19C Module need WiFi?+
No. The Winsen MH-Z19C Module works standalone.
Is the Winsen MH-Z19C Module worth it in 2026?+
At $25, the Winsen MH-Z19C Module is a solid choice for DIY projects and budget-conscious buyers. Its NDIR sensor puts it ahead of cheaper eCO2 estimators. Compare alternatives in our monitor comparison tool before buying.