Issue

I try to understand the Firestore pricing by recalculating their Firestore pricing example (https://cloud.google.com/firestore/docs/billing-example#see-chats). I am not able to understand their network egress calculation per task.

From my point of view, they split up the network egress bill into 2 tasks.

1. See lists: 5 app openings * 10 updated chats * 0.5KB Group document size transit = 25KB Networking

2. Read messages: 30 new messages * 0.25KB message document size transit = 7,5KB

3. Total: 25KB + 7,5KB = 32,5KB

But in their overview, the documentation says:

Network Egress: (50 * 0.25KB) + (30 * 0.25KB) = 20KB / user / day

Questions

Did I understand the calculation correctly? Why is there a difference? What am I doing wrong or is the documentation slightly wrong?

Please provide a calculation example if possible.

Screenshots: