Download Time Calculator
Estimate download time from file size and connection speed.
How long will it take?
The time to move a file comes down to its size and your connection speed, with one catch: sizes are in bytes and internet speeds in bits, a factor of eight apart. This calculator keeps the units straight.
A 5 GB file over a 100 Mbps link takes about 6 minutes 40 seconds at best. Real transfers run slower thanks to overhead and congestion, but this gives you the theoretical floor.
Practical and private
The estimate is computed in your browser, so nothing you enter is uploaded.
Frequently Asked Questions
How is the time calculated?
File size is converted to bits and divided by the connection speed in bits per second, giving the theoretical minimum time.
Why is my real download slower?
Overhead, congestion, server limits, and disk speed all add time. Treat this as the best-case estimate.
Mind the units
Connection speeds are usually in megabits per second (Mbps) while file sizes are in megabytes (MB) — eight times larger. The tool handles the conversion.
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