Cloud Firestore: How is read calculated?

In Cloud Firestore we are charged for read/write/delete operations. Perhaps this is obvious for some but I could not find anywhere what is considered read. If I have a collection of 10 records and I fetch them all in form of a list, does it count as 10 reads or 1 (since I read only once from the database)?

Since you're reading 10 documents, so you'll be charged for 10 document reads. The number of read API calls you use is not relevant here.

Also see:

• Firestore read/write pricing; does .limit(25) counts as 25 reads or one?
• https://stackoverflow.com/questions/48837464/understanding-firestore-pricing
• Firestore Pricing - Does The Amount of Documents In a Collection Matters?
• QuizApp - Firebase/ FireStore Reads

Not the same use-case, but I also experimented with measuring document reads on the server that you can read about here: Counting document reads per user in Firestore