What is USB flash memory?
A USB flash drive, also known as a thumb drive, pen drive, or flash memory stick, is a small data storage device that uses flash memory and contains an integrated USB interface [1]. Unlike traditional storage like hard disk drives (HDD) or solid state drives (SSD) that contain spinning disks or semiconductors, flash drives use flash memory chips to store data [2].
Flash memory is a type of electronically-erasable programmable read-only memory (EEPROM) that can be electrically erased and reprogrammed. It allows fast access times for reading and writing data. When plugged into a USB port, the flash drive appears as a removable drive and allows seamless data transfer between devices [3].
Compared to HDDs and SSDs, flash drives are smaller, faster, portable, and have no moving parts, making them more shock-resistant. However, they typically have less storage capacity. Common USB flash drive capacities range from 1GB to 1TB.
USB Flash Drive Capacity
Typical USB flash drive capacities range from 2GB to 256GB. Lower capacity drives like 2-16GB are common for everyday file transfers, while higher capacity drives up to 512GB or 1TB are used for storing large media files or system backups.
Currently, the largest commercially available USB flash drive is the TEAMGROUP C231, which offers up to 2TB of storage. Prototypes up to 8TB have been demonstrated, but are not widely available.
The maximum capacity of a USB flash drive is limited by the file system, connector standards, and flash memory technology. Most use FAT32 which has a maximum volume size of 2TB. The USB 2.0 interface limits transfer speeds on large drives. And multi-layer flash memory cells eventually limit further expansion of storage density.
So in summary, while 2TB USB drives are now commercially available, the USB interface and file system limits mean much larger capacities are currently impractical for widespread consumer use.
File size basics
A digital file’s size refers to how much data it contains, measured in units like megabytes (MB) or gigabytes (GB). The size depends on factors like resolution, duration for media files, and complexity for documents or programs. Higher quality or longer duration equals larger file sizes.
Typical large file types include:
- Videos – A 5 minute 1080p video can be 500MB to 1GB. 4K video files are even larger.
- Photos – A high resolution photo can easily be 10-20MB.
- Games and programs – Modern games average 35-50GB, with some over 100GB.
- Documents – Complex reports with images may be 50-100MB.
As digital media quality improves over time, average file sizes tend to increase. What used to fit on a floppy disk decades ago now often requires Blu-Ray discs, USB drives, or cloud storage.[1]
USB drive format types
The two most common file formats for USB drives are FAT32 and NTFS. FAT32 has a maximum file size limit of 4GB, which means you cannot save a file larger than 4GB onto a FAT32 formatted USB drive. This is because FAT32 uses 32-bit address pointers for file allocation, limiting the maximum file size to 4,294,967,295 bytes (4GB).
In contrast, NTFS uses 64-bit address pointers allowing for much larger file sizes. The theoretical limit of an NTFS volume is 264 bytes which equates to over 16 exabytes. Realistically, NTFS supports maximum file sizes up to 16TB. This makes NTFS better suited for large files over 4GB like HD video files, disk images, and database files. NTFS also offers advantages like encryption, compression, permissions, and improved reliability over FAT32.
To save a 5GB (or larger) file to a USB drive, the drive must be formatted with NTFS rather than the default FAT32 format. NTFS is natively supported in modern versions of Windows. While NTFS drives can be accessed on Mac OSX and Linux through third-party software, FAT32 may provide better cross-platform compatibility if you don’t need to store files over 4GB.
Why file size matters
When copying large files to a USB flash drive, you may run into issues because of how data is stored on these devices. USB flash drives use a filesystem format like FAT32 or exFAT which divides the storage space into small sections called sectors or clusters. Each sector or cluster has a limited size, usually 4KB.
Large files that are bigger than a single sector have to span across multiple sectors on the drive. This can cause performance issues when reading or writing the files since the filesystem has to access each part of the file separately across different locations on the flash drive. The more sectors the large file spans, the more work the flash drive has to do.
For very large files over 4GB, a standard format like FAT32 has a hard limit on maximum file size it can handle in a single file. That’s why you may get errors trying to copy over a big ISO disc image or video file even if there’s technically enough free space on the USB drive.
Solutions for large files
If the file you want to transfer is too large for your USB drive, there are a few potential solutions:
One option is to split the file into smaller parts that will fit on the drive. You can use free software like Split and Concatenate to divide a large file into chunks under 4GB each. Transfer the chunks to the USB drive separately, then use the software again on the other computer to merge them back into one file.
You may also consider getting a higher capacity USB drive that can hold larger files intact. Many drives now offer 64GB or even 256GB of storage. Just make sure your computer’s operating system supports the full capacity before purchasing.
For extremely large files, cloud storage services like Google Drive or Dropbox may be a better solution. You can upload the file to cloud storage from one computer, then download or access it from any other device. Most cloud services offer some free storage space to start.
In a pinch, you could transfer large files over a local network instead of by USB drive. Setup a shared folder on one computer, copy the file there, then access the shared folder from the other computer to download it.
Optimizing USB performance
USB flash drives use flash memory, which is much faster than traditional hard drives. However, there are still some things you can do to optimize performance.
Choosing the right format type is important. FAT32 is compatible with more devices, but has a maximum file size of 4GB. exFAT and NTFS have much higher maximums, but may not work on older devices. For large video files, NTFS is generally the best choice [1].
Investing in a quality USB drive also makes a difference. Look for read/write speeds of at least 100MB/s for fast transfer. USB 3.0+ drives will outperform older USB 2.0 models. Top brands like SanDisk offer high-performance options [2].
While HDDs have higher capacities, flash drives are much faster for transferring files. A typical hard drive maxes out around 100-200MB/s, while the fastest USB 3.2 drives reach 2000MB/s. For quickly moving large files, USB is the clear winner [3].
When to Use Alternative Storage
If you need to store files larger than 4-5GB, a standard USB flash drive is not the best option. For large storage needs, you’ll want to look into alternative solutions like external hard disk drives (HDDs), solid state drives (SSDs), network attached storage (NAS), or cloud storage.
External HDDs use traditional spinning hard disk technology and are a common choice for expanded storage. Models with 1-5TB of space are readily available at reasonable prices. HDDs can handle very large individual files, with current limits typically in the 1-2TB range per file. However, they are slower and less rugged than SSD options.
External SSDs utilize flash memory and have faster read/write speeds, better durability, silent operation, and lower power needs. They are more expensive per gigabyte compared to HDDs, but 1TB+ options are available. SSDs have max file size limits of 16TB or higher.[1]
For centralized storage on a home or office network, a NAS allows multiple users to easily access, share, and back up files. NAS devices are available with multi-disk capacity, allowing 20TB or more of total storage. Top-end models can handle individual files up to 1-2TB in size.
Finally, cloud-based storage services offer simple, flexible scaling to terabyte or higher capacities. However, continuous internet access is required and uploading very large files can be impractical. Most cloud services have file size cutoffs between 10-100GB.
When working with 5GB+ files, evaluating these alternative storage technologies for capacity, speed, connectivity, and budget will lead you to the best solution.
[1] https://www.pcworld.com/article/406861/best-external-drives.html
Latest USB Tech Improvements
The latest advancements in USB technology center around the USB 3.2 and USB-C standards. USB 3.2 enables much faster data transfer speeds compared to previous USB versions, with theoretical maximum speeds up to 20Gbps. This allows for lightning fast file transfers and improved performance when working with large files or running applications directly from a USB drive.
USB 3.2 achieves these faster speeds through multi-lane operation, meaning multiple data paths are used simultaneously. The latest USB 3.2 version 2×2 uses two lanes in both directions compared to USB 3.2 Gen 2’s single bi-directional lane.
USB-C is a reversible, connector shape that enables a unified port design across platforms and devices. USB-C ports can support a wide range of USB standards including USB 3.2 for maximum compatibility. The small USB-C connector combined with high-speed USB 3.2 makes it easy to add substantial capacity to ultraportable devices.
Together, these capabilities allow modern USB drives to store files up to 2TB and transfer at speeds up to 1GB per second. For large files like high-resolution photos, videos, or even entire operating system installations, today’s USB drives offer an incredibly convenient portable storage solution.
Sources:
[1] https://www.wired.com/gallery/best-usb-flash-drives/
[2] https://www.nytimes.com/wirecutter/reviews/the-best-usb-3-0-thumb-drive/
Summary
Large files that exceed a USB flash drive’s capacity simply cannot be transferred in their entirety. Key reasons include the drive’s storage size, file system limitations, and performance bottlenecks. While USB drives continue to increase in capacity, there are better alternatives for storing and transferring files over 4GB in size.
Cloud storage services offer unlimited capacity and high-speed transfers for large files. External hard drives and SD cards provide a compromise with expanded local storage. For the fastest speeds, use the exFAT file system on your USB drive, or look for high-performance USB standards like USB 3.2 for newer devices.
The most practical solution is to split or compress large files into smaller chunks that will fit on your USB flash drive’s available space. While USB drives have limits, there are many workarounds for transferring big files through optimized formats, storage devices, cloud sharing, and file management.