Estimate the object storage capacity required at the end of a planning period from current data, organic growth, new monthly ingestion, retention, and a safety buffer. The calculator separates the raw forecast from reserve capacity so teams can plan without confusing expected demand with operational headroom.
Next month data = Current data × (1 + growth) + Monthly ingestion × retention
Required capacity = Ending data × (1 + safety buffer)
The main result is the provisioned capacity target after applying the safety buffer. The raw forecast represents expected retained data before reserve capacity.
This model treats retention as the share of each month’s new ingestion that remains stored. It does not model age-based deletion cohorts or compression changes.
Starting with 100 TB, adding 8 TB monthly at 90% retention, growing existing data 2% monthly for 12 months, and adding 20% buffer produces the displayed requirement.
Use a period that matches your invoice and a workload window representative of normal operations. Avoid mixing daily usage with monthly charges.
Yes. The formulas are provider-neutral, but you should enter costs, discounts, and units from the provider’s own bill or quote.
Enter net costs after recurring credits when comparing actual bills. Model temporary promotional credits separately so they do not distort a long-term estimate.
Invoices can include tiered rates, regional pricing, taxes, free allowances, minimum charges, and timing adjustments that this planning model does not reproduce.
Use average data for unit economics and routine utilization. Use peak data and an explicit safety buffer when the decision concerns capacity or resilience.
| Input type | How to use it |
|---|---|
| Cost or capacity | Use values from the same scope and period. |
| Percentage | Enter the displayed percent, such as 20 for 20%. |
| Planning horizon | Use whole months and revisit assumptions regularly. |