Transfer Time Calculator
Calculate how long a file takes to transfer at a given speed.
Use a realistic sustained speed to get a useful approximation.
What this tool does
Estimate how long a copy or transfer may take from data size and sustained throughput. Use a realistic measured rate rather than the interface maximum; small files, protocol overhead, storage speed, cache and competing activity can make actual transfers slower.
How to use it
Enter the values requested by the calculator and check the result together with the notes shown below it.
Practical example
Use a realistic example from your own setup to compare scenarios. The result is a reference, not a replacement for manufacturer specifications.
How to interpret the result
Treat the result as an estimate whenever real-world factors are not available to the browser. For hardware, network or safety decisions, verify the relevant technical specifications.
Frequently asked questions
Why do real copies take longer?
The stated speed is theoretical: the drive, cable, file sizes and system overhead usually reduce it.
Is it better to copy one large file or many small ones?
One large file usually copies faster than thousands of small ones of the same total size, because of per-file overhead.