Calculator Inputs
Responsive calculator grid: 3 columns large, 2 medium, 1 mobile.
Example Data Table
Use these sample scenarios to validate your assumptions or explain results to stakeholders.
| Scenario | Primary TB | Copies | Duplicate % | Compression | Physical TB | Saved TB | Saved % |
|---|---|---|---|---|---|---|---|
| Virtual machine backup estate | 120.00 | 2 | 68.00% | 1.50 | 88.70 | 271.30 | 75.36% |
| File archive environment | 75.00 | 1 | 55.00% | 1.30 | 58.88 | 91.12 | 60.75% |
| Database copy consolidation | 200.00 | 3 | 72.00% | 1.80 | 146.61 | 653.39 | 81.67% |
Formula Used
1) Logical Estate
Logical Estate (TB) = Primary Dataset × (1 + Additional Copies)
2) Unique Data After Deduplication
Unique Data (TB) = Logical Estate × (1 − Duplicate %)
3) Compressed Unique Data
Compressed Unique (TB) = Unique Data ÷ Compression Ratio
4) Final Physical Capacity
Physical Required (TB) = Compressed Unique × (1 + Metadata Overhead %) × (1 + Recovery Reserve %)
5) Savings and Cost Impact
Storage Saved (TB) = Logical Estate − Physical Required
Savings % = Storage Saved ÷ Logical Estate × 100
Annual Cost Saved = (Logical Estate − Physical Required) × Annual Cost per TB
This model assumes the same growth rate affects both logical and deduplicated storage over the selected analysis horizon.
How to Use This Calculator
- Enter your primary dataset size in terabytes.
- Set how many additional logical copies exist, such as backups or replicas.
- Estimate the duplicate percentage in the full logical estate.
- Enter the compression ratio expected after duplicate removal.
- Add metadata overhead and recovery reserve percentages.
- Define annual growth, analysis years, and annual cost values.
- Press Calculate Savings to show results above the form.
- Use the CSV and PDF buttons to export the computed summary.
Frequently Asked Questions
1) What does this calculator measure?
It estimates how much physical storage you may avoid buying after deduplication, compression, reserve space, and operational cost factors are applied.
2) Why include additional copies?
Many environments store backups, replicas, test copies, or snapshot chains. Those copies increase the logical estate and usually raise the deduplication opportunity.
3) Does deduplication replace compression?
No. Deduplication removes repeated blocks or files. Compression shrinks the remaining unique data. Many storage platforms use both methods together.
4) Why do metadata overhead and reserve matter?
Real systems need index space, metadata structures, rebuild room, and recovery headroom. Ignoring those items often makes storage plans too optimistic.
5) Can the savings percentage be low?
Yes. Low duplication, weak compression, high overhead, or small copy counts can all reduce the benefit and produce smaller savings.
6) Is capacity saving the same as cost saving?
Not always. Capacity saved is measured in terabytes. Cost saved depends on your yearly storage and power assumptions, which can vary widely by platform.
7) How accurate are the projections?
They are planning estimates. Actual outcomes depend on workload mix, data change rate, platform design, retention policy, and vendor implementation details.
8) Can this be used for cloud and on-premises storage?
Yes. The model is technology-neutral. You only need reasonable assumptions for capacity growth, duplicate rate, compression, and annual cost inputs.