The option to export the data from your Airthings smart monitor is available using the Airthings Dashboard.
Step 1: Login to the Airthings Dashboard with the same email and password as you use for your Airthings app.
Step 2: Select Devices from side menu
Step 3: Select the device you wish to export data from, then click Export to CSV.
NOTE: the timestamps in the csv file are automatically in UTC (Coordinated Universal Time) so please take this into consideration when viewing your data.
From this point, you can open the csv file with your preferred application for spreadsheets.