Download Time Calculator
Estimate transfer time from file size, bandwidth and efficiency, with explicit decimal/binary size units and bit-per-second network units.
Set your values
Adjust the values, then calculate your result.
How to use Download Time Calculator
- Enter file size with its decimal or binary unit.
- Enter the link rate in bits per second and choose an efficiency estimate.
- Calculate theoretical duration and compare assumptions with actual transfers.
Keep bytes and network bits separate
One byte contains eight bits. Decimal size units use powers of 1000, while KiB, MiB and GiB use powers of 1024. Network Kbps, Mbps and Gbps use powers of 1000 bits per second. The calculator applies your efficiency percentage to the nominal connection rate before estimating duration.
An estimate is not a throughput guarantee
Protocol overhead, latency, congestion, server limits, parallel transfers and changing connection quality can alter real results. Efficiency is an explicit assumption rather than a measured property. The output shows bytes, effective bit rate and duration in seconds, minutes and hours. It does not test your network connection or request a remote file.
Why is 100 Mbps not the same as 100 MB per second?
Mbps measures millions of bits per second; MB/s measures millions of bytes per second. Divide the bit rate by eight before comparing byte transfer rates.
Is input uploaded?
Processing takes place in your browser. This tool does not send your input or selected files to a conversion API.