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Download time calculator

An estimate from your file size and connection speed.

Use 100 for the stated speed, or lower it to allow for a slower transfer.

Enter the file size and connection speed.

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From file size to transfer time

Divide the file size in bits by the connection speed in bits per second. A 1 GB file contains 8 billion bits, so at 100 Mbps, the ideal time is 80 seconds, or 1 minute 20 seconds. At half that speed, it takes 160 seconds.

The expected-share field scales your entered speed. It does not run a speed test or inspect your connection. For a better planning estimate, use the sustained speed from a recent transfer to the same service.

Choose matching units

KB, MB, GB, and TB use powers of 1,000. KiB, MiB, and GiB use powers of 1,024. A GiB is therefore larger than a GB, even when an operating system labels both casually as gigabytes. NIST explains binary prefixes.

A speed advertised by your internet provider is usually in bits per second. A download window may show bytes per second. Select the unit displayed beside your number. This estimate excludes connection setup, pauses, decompression, and installation time.

FAQs

Why is Mbps different from MB/s?

A byte contains eight bits. Mbps measures millions of bits per second, while MB/s measures millions of bytes per second. A 100 Mbps connection is at most 12.5 MB/s before overhead.

How can I estimate upload time?

Enter your upload speed, which can differ substantially from your download speed. The calculation is the same.

Why can a transfer take longer than this estimate?

Your entered speed may be a maximum rather than a sustained rate. Server limits, network overhead, and other traffic can slow the transfer. Use the expected-share field to estimate a slower rate; 50% doubles the ideal time.

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