Can I use external drive for backup and storage?

Using an external drive for backup and storage is a common practice for many computer users. External drives provide a convenient way to expand your storage capacity, keep backups of important files, and even transfer data between computers. In most cases, you can use an external drive without any issues. However, there are some factors to consider when relying on external drives for backup and storage.

Quick Answers

Here are quick answers to common questions about using external drives for backup and storage:

  • Yes, you can use an external drive for backup and storage. External drives connect to a computer via USB, Firewire, Thunderbolt, or wirelessly. They provide expanded storage space and portability.
  • External hard drives and SSDs are the most common types of external drives used for backup and storage. They offer large capacities for storing files.
  • To use an external drive, you simply plug it into your computer via the appropriate cable or connect wirelessly. The drive should then appear as available storage space.
  • Backup software like Apple Time Machine or Windows Backup can automatically back up your files to an external drive.
  • Advantages of using external drives include expanded storage, portability, the ability to easily share files by disconnecting the drive, and keeping backups separate from your main computer.
  • Potential downsides include drive failures, reliance on a single copy of data, misplacing small drives, and purchasing multiple drives to have sufficient backups.
  • Following best practices, like routine drive health checks, keeping multiple backups, storing drives safely, and encrypting sensitive data, can minimize risks.
  • Overall, external drives are very useful for backup and storage as long as you take some basic precautions.

What Types of External Drives Can You Use for Backup and Storage?

There are several different types of external drives that are well-suited for backup and storage purposes:

External Hard Disk Drives (HDDs)

External hard disk drives are very common and provide large capacities, typically from 500GB up to 10TB for desktop drives. An external HDD contains a standard hard drive inside an enclosure with external ports/cables for connectivity. HDDs store data on rapidly spinning disks or platters inside the drive. They offer reliable performance and ample space for backups and storage at relatively low cost. Portable external HDDs do not require a separate power source and are very easy to use.

Solid State Drives (SSDs)

External solid state drives use flash memory to store data instead of spinning platters. They provide extremely fast file transfer speeds, rugged durability, and quiet operation. External SSD capacities range from 250GB up to 8TB for portable flash drives. Larger external SSDs are available. With no moving parts, SSDs use less power and can access data much more quickly than HDDs. The downsides are higher cost per gigabyte and limited capacities compared to HDDs.

RAID Array Drives

For backups and storage on a larger scale, multiple drives can be configured together in a RAID (Redundant Array of Independent Disks) array. This combines two or more drives to increase speed, capacity, or redundancy. A simple example is RAID 1 which mirrors two drives for built-in backup. More advanced RAID setups can achieve very large capacities with the ability to withstand drive failures. RAID external drive enclosures provide pre-configured RAID using multiple internal drives with single external access.

Network Attached Storage (NAS) Devices

Network attached storage works like an external drive but connects via Ethernet or WiFi instead of USB or Thunderbolt. This allows easy access for backup and storage from multiple computers on a network. NAS devices often include RAID capabilities for increased redundancy and capacities. Synology and QNAP are leading brands of NAS units for home and small business use.

How Do You Use an External Drive for Backup and Storage?

Using most external drives for backup and storage is very simple. Here are the basic steps involved:

  1. Connect the external drive to your computer via the appropriate cable (usually USB, Thunderbolt, or FireWire). For wireless external drives, connect via WiFi.
  2. Allow any drivers or software to install if prompted.
  3. The external drive should then appear as an available drive within your file explorer and other storage utilities.
  4. To back up files or move them to the external drive, simply drag and drop files and folders, or use your backup software’s interface.
  5. Safely eject the external drive before disconnecting it physically.

This process works the same across Windows, Mac, and Linux operating systems. Most external drives come ready to use out of the box and do not require any special drivers or configuration. Always safely eject the drive before disconnecting to avoid potential file corruption.

Using Backup Software with External Drives

For automated backups, you can use the backup software built into Windows and macOS, or third-party backup tools. Here are some examples:

  • Windows File History – Automatically backs up files to external drives as specified
  • Mac Time Machine – Backs up entire Mac to external drives for full system restores
  • Acronis True Image – Creates full system image backups to external drives
  • Carbonite – Backs up files to cloud and external drives automatically

The specific steps to set up backups will vary depending on the software used. Generally, you select your external drive as the backup destination location, choose files/folders to back up, and schedule automatic backups. Backup software can provide valuable protection against data loss when used consistently with external storage.

What Are the Advantages of Using External Drives for Backup and Storage?

There are several key benefits to using external drives for backup and storage:

Expanded Storage Space

External drives provide virtually unlimited extra storage capacity for backing up files and expanding your overall storage. A basic 2TB portable external HDD can store hundreds of thousands of files and photographs.

Portability and Sharing

The ability to disconnect and transport external drives offers convenient mobility and sharing capabilities. You can easily bring large file archives anywhere or share them across multiple computers.

Separate from Main Computer

Keeping backups on an external drive protects your data against hardware failures or disasters affecting your main computer. Drive failures, user errors, malware, and other computer issues will not impact your backups stored on disconnected external drives.

Reliability and Speed

Modern external HDDs and SSDs provide very reliable and fast data storage and retrieval – on par with internal hard drives. Both HDD and SSD external drives excel at reliably storing and accessing large media libraries, archives, and disk images.


Storage capacity is highly scalable when using external drives. You can always plug in a higher capacity drive as your needs grow. RAID arrays and NAS enclosures offer essentially unlimited storage scalability for backups and archives.


External drives work seamlessly with all operating systems and hardware, offering universal storage. The same external drive can typically work across Windows, Mac, Linux, desktops, laptops, tablets, media players, smart TVs, game consoles, and more.

What Are the Potential Downsides of Using External Drives for Backup?

While very useful, relying solely on external drives for backup and storage also come with some risks and downsides to consider:

Drive Failures

Any hard drive, whether internal or external, can eventually fail resulting in complete data loss if backups don’t exist elsewhere. External HDD mechanisms and SSD memory cells wear out over time.

Single Point of Failure

Keeping your only backup on a single external drive creates a single point of failure risk. If that drive fails or is lost/stolen, you have no other backups to restore from.

Small Drives Can Be Lost

Tiny portable external drives are easy to misplace or lose, an especially big risk for drives you carry around. A lost drive means lost backups.

Require Additional Expense

There is added expense involved in purchasing external drives exclusively for backup versus using cheap or spare internal drives.

Insufficient Redundancy for Critical Files

Backing up to just a single external drive may provide inadequate redundancy for critical or irreplaceable documents and data archives. More backups are better.

Security and Reliability Varies

Not all external drives are secure or offer the same reliability. Cheaper drives tend to fail more quickly and may not provide advanced data integrity checking capabilities.

Best Practices When Using External Drives for Backup

To maximize the robustness and effectiveness of your backup strategy using external drives, experts recommend following these best practices:

Use Multiple Drives/Locations

Maintain backups on at least two external drives, preferably with one drive kept in a separate physical location for protection against disasters like fires, floods, or theft. Backup redundancy is key.

Automate Backups

Use automatic backup software scheduling to ensure consistent and routine backups rather than sporadic manual backups. This helps avoid missing critical files that change frequently.

Encrypt Sensitive Data

Keep personal and sensitive data protected on external backup drives using encryption. This guards against unauthorized access if a drive is lost or stolen.

Monitor Health

Check your external drives periodically with disk health utilities to confirm they are functioning normally and allowing you time to take corrective action at the first signs of potential failure.

Store Safely

Keep backup drives reasonably protected in secure locations away from environmental threats like fires, floods, and excessive heat which could destroy them.

Consider Offsite and Cloud Storage

Supplement external drive backups with copies stored in secure remote locations or cloud storage for maximum data resilience against localized catastrophes.

Use Quality Drives

Choose reliable external drives from reputable manufacturers that provide at least two-year warranties and undergo rigorous testing procedures.

Verify Backups

To confirm backups are working as intended, periodically perform sample test restores of files from your external backups to ensure you can successfully recover data when needed.

External SSD vs HDD for Backup

When selecting an external drive for backup purposes, you’ll generally be choosing between solid state drives (SSDs) or traditional hard disk drives (HDDs). Here’s how they compare:

External SSD External HDD
Cost Per GB Higher Lower
Maximum Capacities Lower (2 – 8TB) Higher (10TB+)
Data Access Speeds Much Faster Slower
Ruggedness/Shock Resistance More Resilient More Vulnerable
Noise Level Silent Audible Spinning
Power Efficiency Lower Power Draw Higher Power Draw

SSDs provide speed, resilience, efficiency, and silent operation at increased cost, while HDDs offer large capacities and lower cost at the expense of some performance, fragility, and noise. In general, SSDs work very well as backup drives when their capacities and price points fit your budget.

Can You Use an Old Hard Drive as External Storage?

In most cases, you can absolutely repurpose an older unused internal hard drive as an external drive for backups and storage. This is a great way to reuse old HDDs and SSDs.

There are easy-to-use external enclosures available that allow you to install an internal drive and connect it via USB, Thunderbolt, or other ports. For example, you could install an old 3.5″ desktop HDD into an external enclosure with its own power supply. Then just connect the enclosure via USB whenever you need access to the drive.

Some things to keep in mind when using older drives for external storage:

  • Check drive health – Use disk utility software to confirm the drive is fully functional first.
  • Reformat if necessary – If recovering data from the old drive, reformat it after to erase existing partitions.
  • Use appropriate enclosures – Select enclosures designed for the type/size of drive being used.
  • External power may be required – 3.5″ drives may need enclosures with power adapters.
  • Legacy technology – Very old drives may not work with newer computers due to incompatible interfaces.

Overall, repurposing old internal hard drives for external storage and backup is reliable and affordable. Just be sure to verify drive health and use high quality enclosures for the best experience.


External hard drives and SSDs provide a versatile, simple, and low cost solution for expanding your storage capacity for backups, archives, data portability, and more. Both HDD and SSD external drives have advantages and appropriate uses for backup and storage purposes. Following best practices for drive selection, redundancy, health monitoring, encryption, and physical handling is important to protect your irreplaceable data stored on external drives over the long term.