Download Time Calculator
Estimate transfer time from file size and connection speed while distinguishing bytes from bits and decimal from binary storage units. Model unavailable bandwidth and several equal-size files sharing one connection, then compare a second speed.
Your result
How the calculation works
Seconds=(bytes per file×8×file count)/(connection bits per second×usable fraction). Usable fraction=1−overhead/100. MB/s multiplies by eight to get Mbps.
Worked example
A 1 GB file over 100 Mbps with 10% unavailable bandwidth takes about 88.89 seconds, displayed as 1:29. At 50 Mbps it takes about 177.78 seconds. One GiB is larger than one GB.
Assumptions and limitations
Connection is shared by all files. Transfers are assumed to run steadily; concurrency does not create extra bandwidth. Displayed clock times round to seconds. Overhead must be below 100%.
Advertised ISP speed is usually a ceiling. Congestion, Wi-Fi, latency, remote-server limits, protocol behavior and other devices can make actual transfers slower.
Sources and editorial responsibility
Maintained by Renvoro Pty Ltd. Sources inform the methods and assumptions shown here; outputs have the limitations described on this page.
Method reviewed 2026-10-13. Calculation standards · Report an issue