Flash drives, also known as USB drives or thumb drives, and hard disk drives (HDDs) are two common options for digital data storage. Both allow you to store, access, and transport your files, photos, videos and other data. Long term storage refers to keeping your data safe over an extended period of time, from months to years or even decades.
Flash drives are small, lightweight portable storage devices that consist of flash memory chips and connect to devices via a USB port. Hard drives contain rapidly spinning magnetic disks inside a protective casing and connect to computers internally or externally via USB, FireWire, eSATA or wirelessly. Both offer ways to archive important data you want to preserve and access in the future.
Storage Capacity
When it comes to storage capacity, hard drives tend to offer much larger maximum capacities compared to flash drives. Consumer-grade hard drives today commonly offer capacities up to 10TB or more, with high-end models reaching 16TB or higher. In comparison, most standard flash drives on the market today top out at 2TB. There are some high-capacity flash drives that can store up to 4TB, but these remain relatively rare and expensive.
The reason for this significant difference comes down to the underlying storage technologies used. Hard drives store data on quickly rotating platters coated with magnetic material, allowing immense amounts of data to be stored in a small area. Flash drives instead store data on memory chips made from flash memory, which offers faster access times but lower overall storage density. While flash storage densities continue to improve each year, hard drives are still far ahead when it comes to maximizing sheer capacity.
If your primary goal is to store very large amounts of data, such as backups, media libraries, or archives, a hard drive will allow you to fit vastly more data in the same physical space compared to a flash drive. For smaller storage needs under 1TB, a flash drive may meet capacity requirements while providing other advantages. But when it comes to the highest capacities, hard drives have a clear edge.
Physical Durability
Flash drives are generally more portable and compact than external hard drives, making them more susceptible to physical damage if dropped or mishandled. Their small size and lack of moving parts can lead some to believe they are indestructible, but flash drives can and do fail from frequent drops, liquids, magnets, and extreme temperatures (Source 1).
In contrast, external hard drives contain moving parts like disk platters and read/write heads that can break from shock or drops. However, modern external hard drives contain shock protection and rugged enclosures to better withstand bumps and vibration. Overall, today’s external hard drives are remarkably durable devices capable of lasting for years with proper handling (Source 2).
For lifespan, flash drives will generally last 5-10 years with normal use before degrading, whereas hard drives can often operate reliably for 3-5 years or more before failure. But hard drives do have higher total capacities and can withstand more write cycles over time compared to flash memory. With careful treatment, both can provide reliable storage for many years.
File Transfer Speed
When it comes to read and write speeds, flash drives are generally faster than hard drives for small amounts of data. This is because flash drives use NAND memory chips rather than spinning platters, allowing for quick access times. According to Quora, a USB flash drive can achieve speeds of around 200-600 MB/s for sequential reads and writes, while a traditional hard drive maxes out at around 100-200 MB/s.1
However, this advantage diminishes as the size of the transferred files increases. Hard drives tend to perform better at sustained data transfers thanks to their higher capacity and disk caching capabilities. As noted on Reddit, a typical 7200 RPM hard drive can achieve 140-180 MB/s sequential reads/writes, which is comparable to many flash drives.2 For large files like movies, hard drives may be faster.
In terms of small, random reads/writes – which are common when accessing small files like documents or photos – flash drives are again much faster due to their lack of moving parts. Overall, flash drives have a speed advantage for most common home and office use cases involving smaller files.
Price Per Gigabyte
When looking at cost efficiency, one of the most important factors to consider is the price per gigabyte (GB). Generally, hard drives tend to offer more storage capacity at a lower cost compared to flash drives.
According to Flash prices drop towards spinning disk levels in 2023, in 2023 the average price per GB for flash drives is around $0.075/GB. Meanwhile, Hard Drives vs. Flash Memory: Cost Per Gigabyte Explained states that hard drives can offer as low as $0.02-0.05/GB.
So when comparing similar storage capacities, hard drives are generally 3-4 times cheaper per GB than flash drives. For example, a 1TB flash drive may cost around $75 while a 1TB hard drive is only $20-25. The larger the storage capacity, the greater the cost difference.
This makes hard drives significantly more cost efficient for storing large amounts of data long term. However, flash drives may be a more affordable solution if only a small capacity is needed.
Power Usage
Flash drives typically require very little power, often drawing it directly from the USB port on a computer or other device. Most flash drives will operate at 5V and under 500mA, meaning they use around 2-2.5W while in active use ([Source 1]). This makes flash drives highly energy efficient.
External hard drives require more power, often needing a dedicated power cable or adapter to operate. A typical 2.5″ external HDD draws around 5V and up to 900mA when active, so around 4-4.5W ([Source 2]). This is about twice the power draw of a flash drive.
The lower power requirements of flash drives make them better suited for mobile use, as they can be powered by laptops and mobile devices without external power. Hard drives may drain a device’s battery faster unless plugged into a wall outlet.
[Source 1] https://solved.scality.com/solved/high-density-power-consumption-hdd-vs-qlc-flash/
[Source 2] https://superuser.com/questions/1171866/what-is-typical-power-consumption-of-2-5-laptop-external-hard-drive-connected-t
Portability
Flash drives are generally much smaller and more portable than external hard drives. A typical flash drive is about the size of a thumb and can easily fit in a pocket or on a keychain. External hard drives, even portable ones, are larger in physical size. While portable external drives may be small enough to fit in a bag or backpack, they are not as effortlessly portable as a tiny flash drive.
The compact size of flash drives makes them extremely convenient for transferring files between different devices. They are easy to carry around and plug into any device with a USB port. External hard drives generally require an AC power source, so they are less convenient for on-the-go file transfers. The smaller physical footprint of flash drives also makes them better for permanently installing in devices, since they take up less space.
Overall, flash drives are far more portable and convenient to transport files. Their miniature size and lack of need for external power gives them a significant edge over external hard drives when it comes to mobility and ease of use for transferring data while traveling or between many devices.
Sources:
https://www.lifewire.com/external-hard-drive-vs-flash-drive-5208546
Encryption & Security
When it comes to built-in security features, flash drives and external hard drives vary significantly. Most flash drives lack any hardware-based encryption, instead relying on software encryption if available. In contrast, many external hard drives offer hardware-based encryption to better protect data. As noted on Quora, hardware-based encryption is more secure than software solutions since the encryption keys are stored on a dedicated chip in the device itself rather than within the system software (source).
Hardware encryption also makes unauthorized access to data on a lost or stolen drive much more difficult. Without the encryption chip present, the data remains scrambled and unreadable. Kingston highlights this advantage of hardware encryption on their blog, stating their encrypted USB drives use dedicated hardware encryption processors rather than less secure software encryption (source).
Additionally, external hard drives tend to have more physical security features like rugged casing and water/shock resistance that help prevent data loss from physical damage. So for optimal built-in security, external hard drives with hardware-based encryption are generally the most secure and tamper-proof option.
When to Use Each for Storage
Both flash drives and hard drives have advantages that make them better suited for certain use cases. Here are some guidelines on when to choose each one:
Use a flash drive when:
- You need to frequently transfer files between devices.
- You need to carry external storage around with you.
- You need to regularly back up and restore data.
- You need to store data temporarily or make quick backups.
Use an external hard drive when:
- You need to store very large files like videos, photos, or games.
- You need expanded storage for a laptop or desktop.
- You need to perform regular backups of your system and files.
- You need to store data long term, like archiving.
So in summary, flash drives are better for portability and convenience, while external hard drives are ideal for expanded storage and archiving large amounts of data long term.
Conclusion
When deciding between a flash drive or external hard drive for long term data storage, there are a few key factors to consider. Flash drives tend to have lower storage capacities and can be less physically durable over time compared to hard drives. However, flash drives excel in portability, speed, encryption capabilities, and low power usage – making them ideal for transporting files or quickly backing up data.
Hard drives offer more storage capacity for lower cost per gigabyte, and new solid state drive models are more durable than traditional spinning hard drives. Hard drives can better withstand accidental drops or impacts. For large backups, archives, or media libraries where capacity and cost are top priorities – an external hard drive is likely the better choice.
Overall, for most general consumer use cases focused on portability and convenience – a flash drive will serve well for transportable files, quick backups, transferring data between devices, and encrypting sensitive information. For large storage needs, backups, and multimedia libraries – an external hard drive is preferable. Evaluate your specific storage requirements and use case to determine if a flash drive or hard drive better suits your long term data storage needs.