USB Transfer Speed Calculator
Estimate how long it takes to copy your files onto a USB flash drive. Pick a file size and USB standard for a realistic, real-world transfer-time estimate - not just the theoretical maximum.
USB speed reference chart
USB standards quote an interface ceiling in gigabits per second, but real-world write speeds are far lower - limited by the flash memory inside the drive, the host port, and whether you are copying one large file or thousands of small ones. The figures below are typical sustained write speeds you can expect day to day.
| USB standard | Interface ceiling | Typical real-world write | 1 GB file ≈ |
|---|---|---|---|
| USB 2.0 | 480 Mbps | 25–35 MB/s | ~30 sec |
| USB 3.0 (3.1 Gen 1) | 5 Gbps | 80–130 MB/s | ~9 sec |
| USB 3.1 Gen 2 | 10 Gbps | 200–250 MB/s | ~4 sec |
| USB 3.2 Gen 2×2 | 20 Gbps | 400–500 MB/s | ~2 sec |
Skip the copying - we preload your drives for you
Every USB Makers order includes up to 500MB of free data preloading, factory-loaded onto your branded drives before dispatch. Catalogues, brochures, autorun links and more - ready the moment your customer plugs in. Need a larger payload? Just ask.
Request a quoteFrequently asked questions
Why is my USB drive slower than the advertised speed?
Advertised figures are interface ceilings (e.g. 5 Gbps for USB 3.0). The actual write speed is set by the NAND flash inside the drive, the controller, your computer’s USB port, and the cable. Most everyday flash drives write at a fraction of the bus limit, which is why our estimates use realistic real-world speeds rather than the theoretical maximum.
How long does it take to copy 1 GB to a USB stick?
Roughly 30 seconds on USB 2.0, around 9 seconds on USB 3.0, and just a few seconds on USB 3.1 Gen 2 or faster. Use the calculator above for your exact file size and standard.
What is the difference between USB 2.0 and USB 3.0 speeds?
USB 2.0 tops out at 480 Mbps (about 25–35 MB/s in practice), while USB 3.0 (also called USB 3.1 Gen 1) reaches 5 Gbps and delivers 80–130 MB/s in the real world - roughly 3–4× faster for large transfers.
Why do lots of small files copy more slowly than one large file?
Each file carries filesystem overhead, so copying thousands of tiny files involves far more start-stop operations than streaming a single large file of the same total size. Expect noticeably slower speeds when transferring many small documents or images.
Can you preload data onto our branded USB drives?
Yes. Every order of branded USB sticks includes up to 500MB of free data preloading, and we can load larger payloads on request. It is a popular option for custom USB sticks supplied to clients and at events.
