Step 1: First, go to the "Import" tab in your Hashnode Newsletter dashboard as shown in the screenshot.
Step 2: Then, check the confirmation box and click the "Import CSV" button. Select the .csv file with your subscriber emails from your system file dialog. Allow the import process to complete.
You'll receive a notification once the import is finished as shown in the screenshot.
Things to note:
The maximum file size allowed is 10 MB
Duplicates/Invalid email addresses will be ignored
Make sure your CSV file has 1 column that contains all the emails