Download Time Calculator

Estimate how long a download will take from the file size and your connection speed.

How long the file will take

A download's time comes down to the file size divided by your connection speed. This estimates it, so you can tell whether a large file is a coffee-break wait or an overnight job before you start.

Enter the file size and your speed to see the estimated time.

The bits-and-bytes gotcha

The single thing that makes download-time estimates wrong is the bits-versus-bytes mix-up. Connection speeds are quoted in megabits per second, but file sizes are in megabytes, and there are eight bits to a byte — so a file downloads at roughly an eighth of the number your connection speed suggests. A hundred-megabit connection moves about twelve and a half megabytes a second. Accounting for that is why a careful estimate matches reality.

Common questions

Why is the download slower than my connection speed?

Speeds are in megabits but files are in megabytes, and a byte is eight bits — so the download rate is about an eighth of the megabit figure.

Will the estimate be exact?

It is a close estimate; real speeds fluctuate with the connection and server, so treat it as a ballpark.

Is anything uploaded?

No. The calculation happens in your browser.

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