Backup Retention Storage Calculator
Estimate the storage footprint of retained full snapshots plus daily incremental backup objects, using your measured backup sizes and storage rate.
A transparent copy-count model; lifecycle policies and deduplication are not assumed. Maintained by Buildopsy · Updated .
Backup retention scenario
Formula and assumptions
Full copies = ceil(retention days ÷ days between full backups). Retained volume = full copies × full size + retention days × daily incremental size.
This intentionally counts stored objects without assuming block-level deduplication, compression, pruning of incrementals around snapshot boundaries, or storage tiering. Enter the post-compression bytes actually billed for one full and one typical incremental. Monthly charge is a steady-state GB-month estimate; restore, request, replication, and minimum-duration fees are excluded.
Frequently asked questions
How is retained backup storage estimated?
It counts periodic full copies over the retention window, rounding the copy count up, and adds the configured incremental volume for every retained day.
Does this include deduplication or compression?
No. Use observed stored sizes after those reductions. Actual backup products can share blocks and retain chains differently, so confirm object counts and billed bytes from your backup system.
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