I wanted to measure CO2 in my office, so I build a C++ WebServer/App
A simple webserver / CO2 Monitor. Contribute to Maddimax/MadCO2 development by creating an account on GitHub.
I wanted to measure CO2 in my office, so I build a C++ WebServer/App launched on January 25, 2019 with 146 votes, #186 of 2,587 launches that month and more than 95% of that year's launches. The site was still online in September 2026, 7 years on.
In plain words
This is a C++ web server and application that measures CO2 levels in an office environment. Built by someone seeking to monitor air quality at their workspace, it provides real-time CO2 data through a web interface. The tool is designed for office workers and anyone interested in tracking indoor air quality metrics. The project is available on GitHub for those who want to set up their own CO2 monitoring system.
written from the facts on this page · September 2026
Does a similar job
all alternatives →- ALAir Lab – A portable and open air quality measuring device2025 · networkedartifacts.com · ▲497
Hi HN! I’ve been working on an air quality measuring device called Air Lab for the past three years. It measures CO2, temperature, relative humidity, air pollutants (VOC, NOx), and atmospheric pressure. You can log and analyze the data directly on the device — no smartphone or laptop needed. To better show what the device can do and how it feels like, I spent the past week developing a web-based simulator using Emscripten. It runs the stock firmware with most features available except for networking. Check it out and let me know what you think! The firmware will be open-source and available…
Low cost CO₂ monitoring (your office) with Prometheus and Go2018 · github.com · ▲127CO₂ & Temperature monitor. Contribute to larsp/co2monitor development by creating an account on GitHub.
Enviro+ for Raspberry Pi – Environmental sensors2019 · shop.pimoroni.com · ▲397Monitor your world with Enviro and Enviro + Air Quality for Raspberry Pi!
A subtly obvious e-paper room air monitorNov 2025 · nicolin-dora.ch · ▲65In the cold season we tend to keep the windows closed. The air gets "stale": humidity often rises above 60 %, which can harm our wellbeing and promote mould. At the same time the CO₂ level in the air increases, which impacts our ability to concentrate. So I built a room air monitor that stays unobtrusive as long as everything is in the green zone, but becomes deliberately noticeable once thresholds are exceeded. For my personal love of statistics I also visualise the measurements in a clear dashboard.
Live Air Quality Monitor2025 · github.com · ▲19A comprehensive indoor air quality monitoring system built with ESP32-C3 Super Mini and multiple environmental sensors. This project helps you monitor CO2, temperature, humidity, volatile organic compounds (VOCs), nitrogen oxides (NOx), and particulate matter (PM1.0, PM2.5, PM10) to maintain healthy air quality in your home or office.
- MCMeasure CO2 emissions of your APIs2022 · docs.stepci.com · ▲20
Have you ever wondered about the carbon footprint of your API? This week, the 27th climate summit takes place in Egypt. This inspired us to draw attention to the emissions produced by our online behaviour. We introduced some CO2-related features to our API testing tool: - Calculate carbon emissions of an API call - Set up a check to validate that your API endpoint doesn't cross the limit when it comes to emissions - Test all your API endpoints and get an approximate calculation of your API emissions in total We hope that by using these features, you will become more aware of the carbon…
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