A registration confirmation email is sent after successfully registering a device. This email will allow you to obtain the read key for your sensor. You’ll want to look at the bottom of the email for a section labeled “Useful Links,” and the link labeled “View on the PurpleAir map.”
The link might look something like this: https://www.purpleair.com/map?zoom=4&lat=40&lng=-110&key=NY8JP6D1SB73V78G
The sensor’s read key is after “key=” meaning that it would be “NY8JP6D1SB73V78G” in this case.
Additional information on using a sensor’s read key in an API call is found in our Making API Calls with the PurpleAir API article.