Add current data
The calculator combines computers, photos, media, projects and other stored files.
MAZENHARD INTERACTIVE NAS PLANNER
How much NAS storage do you really need?
Calculate current files, compounded growth, free-space headroom, RAID overhead and backup copies—then turn the result into a practical NAS and drive recommendation.
STEP 1 · CURRENT DATA
What needs to live on the NAS?
Enter the amount currently used—not the total size of each device.Current data subtotal8.0 TB
STEP 2 · FUTURE & PROTECTION
How should the system grow?
HOW IT WORKS
Four calculations turn files into drives
Compound growth
Future data equals current data multiplied by annual growth for every selected year.
Add headroom
Free space accommodates snapshots, temporary files, databases and unexpected imports.
Apply RAID
Usable capacity is converted into the number and size of physical drives required.
CAPACITY GUIDE
Why raw and usable storage differ
| Example | Raw capacity | Approx. usable | Drive failures tolerated |
|---|---|---|---|
| 2 × 12TB RAID 1 | 24TB | 12TB | 1 |
| 4 × 12TB RAID 5 | 48TB | 36TB | 1 |
| 4 × 12TB RAID 10 | 48TB | 24TB | Varies by failed pair |
| 6 × 12TB RAID 6 | 72TB | 48TB | 2 |
| 8 × 12TB RAID 6 | 96TB | 72TB | 2 |
Simplified decimal estimates before formatting and system overhead. Flexible RAID implementations may calculate mixed drive sizes differently.
DECISION PATH
From storage target to NAS size
Simple, compact and well suited to home backup and smaller libraries.
Better capacity efficiency or mirrored performance with more flexibility.
Two-drive tolerance and good capacity for creators and media archives.
Higher usable capacity, more drives and a longer expansion runway.
GROWTH EXAMPLE
Small annual increases become large
Current files across all devices.
About 61% growth through compounding.
Nearly 2.5 times the starting data.
More than triple the starting data.
BACKUP
Primary capacity and backup capacity are different
Files, applications and media available every day.
USB storage or a second NAS, ideally protected from normal user access.
Cloud storage or another physical location for irreplaceable data.
RAID helps availability after drive failure. It does not replace another copy.
BEFORE ORDERING
Check the whole storage system
Drive compatibility
Confirm exact HDD and SSD models on the NAS manufacturer’s compatibility list.
CMR recording
Prefer suitable NAS-rated CMR drives for predictable RAID behavior unless the manufacturer explicitly supports otherwise.
Network speed
Gigabit suits ordinary backup and streaming. Creators and large transfers may benefit from 2.5GbE or 10GbE.
Power protection
Add a compatible UPS and configure safe automatic shutdown.
Expansion method
Understand whether growth means empty bays, larger drives, an expansion unit or another NAS.
Restore testing
Verify that backups, encryption keys and application settings can actually be restored.
FAQ
NAS storage calculator questions
Why does the calculator compound annual growth?
Each year’s new data becomes part of the next year’s starting amount. Simple addition tends to underestimate fast-growing photo and video libraries.
Why keep 20–30% free space?
Snapshots, indexing, temporary operations, databases and future imports require capacity beyond the files you can see.
Does the calculator include formatting loss?
No. The drive recommendation is a planning estimate before formatting and system overhead, so actual displayed capacity will be lower.
Should backups include the free-space allowance?
The calculator uses the target usable amount for conservative backup planning. A carefully managed backup can be smaller if it excludes replaceable data.
Can I use drives of different sizes?
Some flexible RAID systems support mixed capacities, while traditional RAID commonly uses the smallest drive as the basis. Check the exact NAS implementation.
When should I select RAID 6?
Consider RAID 6 for larger arrays and high-capacity drives when tolerating two simultaneous drive failures is worth the additional capacity cost.
Why might RAID 10 be recommended?
RAID 10 offers mirrored pairs and strong performance, but uses half the raw capacity. It can suit active projects, VMs and predictable rebuild priorities.
What if my result exceeds eight bays?
Consider larger systems, multiple pools, expansion units, a second NAS or professional storage design. Backup and recovery become increasingly important.
Planning notice
This calculator provides educational estimates and does not guarantee compatibility, performance or recoverability. Confirm drive limits, RAID behavior, volume limits and expansion rules in the documentation for the exact NAS model.