[lathiat]

Most of the $60 ones aren’t really measuring CO2. The usual giveaway is if the sensor also measures VOC or TVOC most are estimating the CO2 based on that. Which has only a vague correlation sometimes and not remotely close to useful.

You need a device that specifically quotes having an “NDIR” sensor and most are $100+

[Mutlut]

The one i mentioned btw. only hsa that NDIR sensor and is at 60 bucks: "Hochwertiger NDIR Dual Beam Sensor" <> "high quality NDIR Dual beam sensor"

And it doesn't meassure anything else. So a good point that its not the same thing and if you want both, you probably need to spend 100+