Why downloading 1 GB at 100 Mbps takes 80 seconds ideally, not ten
Network rates commonly use bits, while file sizes commonly use bytes. One byte contains eight bits, so the factor of eight must be included.
Download time calculator →Put both quantities into matching units
Using decimal units, 1 GB equals 1000000000 bytes, or 8000000000 bits. A rate of 100 Mbps is 100000000 bits per second. Dividing gives an ideal duration of eighty seconds. Dividing unrelated displayed numbers without aligning their units does not produce a meaningful time.
Distinguish MB/s from Mbps
A connection rate of 100 Mbps corresponds ideally to 12.5 MB/s because the bit rate must be divided by eight. The lowercase b and uppercase B matter. This tool’s rate field offers bps, kbps, Mbps and Gbps; it does not directly accept MB/s. Convert a byte-per-second reading to the corresponding bit rate before entering it.
Allow for real transfer conditions
With usable bandwidth set to 80%, the effective rate becomes 80 Mbps and the example duration becomes one hundred seconds. That percentage is your scenario assumption, not a measurement performed by this site. Server capacity, wireless conditions, concurrent activity and protocol overhead can affect completion time. The unit converter and time converter help verify the arithmetic, but a clean calculation should still be described as an estimate rather than a promised download time.
Try the calculators
- Download time calculator
Estimate download time from file size, connection rate and usable bandwidth.
- Unit converter
Convert length, mass, area, volume, speed and data size.
- Time conversion
Convert hours, minutes and seconds.