Snapshot and backup storage across retention copies.
Snapshot copies are incremental, so extra copies are cheap β but years of retention and orphaned snapshots pile up. Tier old backups to archive and prune. Pair with the object storage cost calculator.
The Cloud Backup Cost Calculator estimates your monthly backup bill β the recurring charge for keeping your data in cloud storage. It multiplies your protected data volume by the number of retention copies you keep and the provider's price per GB-month, so the stored footprint is far larger than your live data set. The daily change percentage adjusts the estimate for incremental growth, since each backup cycle adds new or modified blocks on top of the baseline. The main drivers are simple: more protected gigabytes, more copies retained, and a higher per-GB rate each push the monthly cost up in direct proportion.
The key trade-off to watch is retention depth versus cost. Every extra copy you keep multiplies your monthly spend, so a long retention policy on a large data set can quietly dominate the bill. A high daily change rate compounds this, because frequent modifications inflate each incremental backup. Before committing, test a shorter retention window or tiered storage to see how much you save β then keep only the copies your recovery and compliance needs actually require, rather than defaulting to the longest option available.
Snapshots are billed per GB-month of stored data. Most are incremental β only changed blocks since the last snapshot are stored β so many retention copies cost far less than the full size times the copy count. Cross-region copies and restores add transfer fees.
Set retention that matches real recovery needs, move long-term copies to cheaper archive tiers, and delete orphaned snapshots from deleted volumes. Old snapshots nobody will ever restore are a common silent cost.