Quick answer

Download time falls in direct proportion to speed: doubling the sustained Mbps halves the ideal time. A 10 GB file takes about 13 minutes 20 seconds at 100 Mbps or 2 minutes 40 seconds at 500 Mbps.

Key takeaways

  • File size must be converted to bits before dividing by bits per second.
  • Doubling the sustained speed halves the ideal transfer time.
  • Use measured long-transfer speed when you need a realistic schedule.

Quick download time chart

These figures use decimal file sizes and assume the listed rate remains constant from start to finish.

File size10 Mbps50 Mbps100 Mbps500 Mbps1 Gbps
1 GB13m 20s2m 40s1m 20s16s8s
10 GB2h 13m26m 40s13m 20s2m 40s1m 20s
25 GB5h 33m1h 6m 40s33m 20s6m 40s3m 20s
50 GB11h 6m2h 13m1h 6m 40s13m 20s6m 40s
100 GB22h 13m4h 26m 40s2h 13m 20s26m 40s13m 20s

How the chart is calculated

Multiply the decimal file size in bytes by eight to convert it to bits. Divide that value by the connection rate in bits per second. The result is the ideal number of seconds.

For example, 10 GB contains 80 gigabits. Dividing 80 gigabits by 100 megabits per second gives 800 seconds, or 13 minutes 20 seconds.

  • Time in seconds = file size in bits ÷ speed in bits per second
  • Decimal 1 GB = 1,000,000,000 bytes
  • 1 byte = 8 bits

Plan with sustained speed, not only plan speed

An internet plan describes the access link, but every download also depends on the source server, route, local network, device, and storage. A short speed test may be faster than a long transfer.

For scheduling, note the stable speed after the first minute of a representative download and use that rate in the calculator.

Decimal and binary file sizes

Network rates use decimal SI prefixes. Some operating systems and applications display file capacity using binary conventions while still writing GB. That can create a small difference between a chart estimate and the displayed size.

NetCalcKit labels its model and uses decimal units consistently so that the assumptions remain clear.

Use the chart as a baseline

The table is best for quick comparisons. Enter your exact size and speed in the download time calculator when the difference between minutes and hours matters.

Use the numbers

Related calculators

Common questions

Questions, answered.

How long does 1 GB take at 100 Mbps?+

The ideal time is about 1 minute 20 seconds using decimal units.

How long does 50 GB take at 500 Mbps?+

The ideal time is about 13 minutes 20 seconds at a constant 500 Mbps.

Does 1 Gbps mean 1 GB per second?+

No. 1 Gbps equals an ideal 125 MB/s because one byte contains eight bits.

Why is a real download slower than the chart?+

The chart assumes a constant full rate. Protocol overhead, Wi-Fi, congestion, source limits, storage, and other traffic can make the real transfer longer.

Sources & review

How this guide was checked.

NetCalcKit reviews formulas against worked examples and uses primary technical references where they apply. Estimates remain clearly labelled because real networks and services vary.