Product review (1 stars): Not accurate
It's supposed to be calibrated from factory, but the temperature is off by 2-3 degrees Celsius and more importantly the humidity is off by 4%-10% (the error range is not consistent for some reason) and I didn't even had the chance to use it (it's like that from the box, first week of use). with that been said, it's just useless for me. it's a cheapo hygrometer, expect nothing. the size is good though (quite small)