Storage Redundancy
Use the Storage Redundancy. Enter Number of drives and Capacity per drive (TB) for a clear result, formula explanation, and practical planning checks.
Storage Redundancy measurements
Enter your values, then calculate.
Result
How to calculate storage redundancy
This calculator estimates usable redundant storage capacity in a RAID-1-style mirrored configuration, where half the total drives provide redundancy.
How the calculation works
Usable capacity = floor(Number of drives ÷ 2) × Capacity per drive.
Example
6 drives at 4 TB each: floor(6÷2)×4 = 3×4 = 12 TB usable.
Frequently asked questions
How is Result calculated?
Result = floor([Number of drives] ÷ 2) × [Capacity per drive].
Is the Storage Redundancy free to use?
Yes — every calculator on Simple Calculator Tools is free, runs in your browser, and does not require an account.
Storage Redundancy
Usable capacity = floor(Number of drives ÷ 2) × Capacity per drive.
Let's understand your storage redundancy result.
Calculate a result above and this guide will help you interpret it using this calculator's own formula and explanation.
Pro Tips for Storage Redundancy
- This models a simple mirrored (RAID-1-style) redundancy scheme where drives are paired — other RAID levels (like RAID-5 or RAID-6) have different, often more storage-efficient redundancy math.
- An odd number of drives leaves one drive unpaired and effectively unused for this specific mirrored redundancy scheme, which is why the floor (round-down) function is used.
Common Storage Redundancy Mistakes to Avoid
- Applying this simple mirrored-pair calculation to a different RAID level (like RAID-5), which has a fundamentally different redundancy and capacity relationship.
When to Use This Calculator
This calculator estimates usable redundant storage capacity in a RAID-1-style mirrored configuration, where half the total drives provide redundancy.