Raid10 Calculator

Setting up a RAID 10 array but unsure about how much usable capacity you’ll get from your disks? Our RAID 10 Calculator takes the guesswork out of planning your storage architecture by giving you instant calculations based on your input. This tool is perfect for IT professionals, system administrators, or home lab enthusiasts looking to design a resilient and high-performance storage system.

In this article, we’ll walk you through how the tool works, how to use it, provide a practical example, and answer common questions related to RAID 10 setups.

What Is a RAID 10 Array?

RAID 10 (also known as RAID 1+0) combines mirroring (RAID 1) and striping (RAID 0). It requires a minimum of four disks and always an even number. RAID 10 offers both high performance and data redundancy. In this configuration:

  • Data is striped across mirrored pairs.
  • Each piece of data is duplicated, offering protection if a disk fails.
  • Only 50% of total disk space is usable due to mirroring.

That’s where this calculator helps—it automates that math so you can focus on the hardware and deployment.

How to Use the RAID 10 Calculator Tool

Using the RAID 10 calculator is extremely simple. Follow the steps below:

  1. Enter the Number of Disks:
    Type the total number of disks you plan to use. 🔹 Note: Must be an even number, and at least 4.
  2. Enter the Size of Each Disk (in GB):
    Input the size of a single disk (e.g., 1000 GB for 1 TB).
  3. Click the “Calculate” Button:
    The tool will immediately compute and display:
    • Usable Capacity (how much of your total space is usable)
    • Redundancy Information (resilience details)
  4. Click “Reset” to Start Over:
    Clears all fields and results to let you try different setups.

Example: Calculate a RAID 10 Setup

Let’s say you’re building a storage array using 8 disks, each with a 2 TB capacity (2048 GB).

  • Enter 8 in the “Number of Disks” field.
  • Enter 2048 in the “Disk Size” field.
  • Click Calculate.

Results:

  • Usable Capacity: 8192 GB (or 8 TB)
  • Redundancy: Can tolerate failure of one disk per mirrored pair

This means out of the total 16 TB (8 disks × 2 TB), only 8 TB is usable due to mirroring. But in return, your data is protected and performance is optimized.

Why RAID 10? Benefits and Use Cases

RAID 10 is ideal when you need a balance between performance and fault tolerance. Here’s why:

🔐 Data Protection

Each disk has a mirrored copy. If a disk fails, its data is still accessible.

🚀 High Performance

Read/write speeds are significantly faster compared to RAID 1 or RAID 5, thanks to striping.

🧰 Use Cases

  • Database servers
  • Virtualization platforms (like VMware or Hyper-V)
  • Mission-critical applications
  • Media editing and production
  • Gaming servers or home NAS setups

Additional Tips for Planning Your RAID 10 Array

  • Always plan for future expansion. Don’t max out your drive bays in your initial configuration.
  • Use identical drives to avoid bottlenecks.
  • RAID is not backup. Always pair RAID with external backups.
  • Monitor drive health regularly using SMART tools.

RAID 10 Calculator FAQs

1. What is the minimum number of disks required for RAID 10?

RAID 10 requires at least 4 disks, and the number must always be even.

2. How is usable capacity calculated in RAID 10?

The formula is:
(Total Disks / 2) × Disk Size
Because half the disks are used for mirroring.

3. What happens if I input an odd number of disks?

The calculator will show an alert. RAID 10 requires an even number of disks.

4. Can I use different-sized disks in RAID 10?

Technically yes, but your array will default to the size of the smallest disk, which wastes space.

5. Is RAID 10 better than RAID 5?

RAID 10 offers better performance and faster rebuild times, but uses more disks for redundancy.

6. What’s the overhead in RAID 10?

50% of your total raw capacity is used for mirroring, so there’s a 50% overhead.

7. How many disk failures can RAID 10 tolerate?

It can survive one disk failure per mirrored pair, but not two failures in the same pair.

8. Does this calculator work with SSDs?

Yes! The type of disk (HDD or SSD) doesn’t affect the calculation.

9. Does RAID 10 increase speed?

Yes, particularly for read/write operations, because of the striped setup.

10. What happens if I refresh the page?

The form resets and clears all your input and results.

11. What does ‘mirrored pair’ mean?

Two disks are paired together where one mirrors the other. This is the RAID 1 part of RAID 10.

12. Can I expand a RAID 10 array later?

Only by adding another pair of disks. You can’t just add one.

13. Is RAID 10 good for gaming servers?

Absolutely. It provides the performance and fault tolerance needed for consistent uptime.

14. Is there any data loss during rebuild in RAID 10?

Unlikely, unless multiple disks in the same mirrored pair fail.

15. Why does the calculator show half the total space as usable?

That’s due to mirroring. Every piece of data is stored twice for redundancy.

16. Can I use the calculator for RAID 0 or RAID 5?

No. This tool is designed specifically for RAID 10 setups only.

17. Can the calculator estimate rebuild time?

No, rebuild time depends on disk speed, system load, and controller performance.

18. What if I input invalid data?

You’ll receive an alert prompting you to correct the inputs.

19. What happens if I use drives of different capacities?

The array will use the capacity of the smallest disk in each mirrored pair.

20. Is RAID 10 suitable for home use?

Yes, especially for home NAS systems that require speed and reliability.

Conclusion

Planning a RAID 10 setup doesn’t have to be complicated. With this easy-to-use RAID 10 Calculator, you can quickly determine your usable capacity and understand your redundancy level before committing to hardware purchases. Whether you’re a seasoned system admin or a beginner setting up a home lab, this tool can help you optimize your storage configuration confidently.