How to use this calculator
- Enter your own values in the labeled fields. Check the units and assumptions before comparing results. Only the fields needed for your selected calculation mode are shown.
- Your answer updates automatically. Review the calculation steps to see exactly how it was calculated.
- Copy, share, save, or download your result. Saved inputs stay on this device.
How the calculation works
A byte contains eight bits. Network speeds usually use bits per second, while files use bytes; decimal and binary file units also differ. The efficiency factor is an explicit allowance for less-than-advertised throughput. Constant throughput is assumed, so real transfers may vary with congestion, latency and source limits.
A worked example
1 decimal GB is 8 billion bits. At 100 Mbps and 100% efficiency, ideal transfer time is 80 seconds.
Reading your result
Use the main result together with its units and supporting figures. Display values are rounded; calculations keep their underlying precision. A change in inputs or assumptions can change the answer. Compare the step-by-step working with your intended use before relying on an estimate.
Frequently asked questions
Are MB/s and Mbps the same?
No. One MB/s is eight Mbps.
Is the result guaranteed?
No. It is a constant-throughput estimate.
Sources & methodology
NIST: international unit conversion factors ↗
Formula review: October 24, 2026. Read our methodology.