Download Time Calculator
Enter a file size and your internet speed to see how long the download takes. You can use the result of your last speed test, or measure your speed here in a few seconds.
Common downloads at your speed
| Download | Typical time | Best case |
|---|
How the time is worked out
Internet speed is measured in megabits per second (Mbps) but files are measured in bytes. One gigabyte is 8,000 megabits, so the time in seconds is the size in gigabytes times 8,000, divided by your speed in Mbps. For example, 1 GB at 100 Mbps takes 80 seconds.
The “typical time” column assumes you get about 90% of your line speed, because of protocol overhead and busy servers. The “best case” column assumes every bit of the line is used, which rarely happens.
Why downloads can be slower than the calculation
- The server limits the speed. A game store or website may send data slower than your line can take it.
- Other devices share your line. Streams and updates take a share of the bandwidth.
- Wi-Fi is slower than the plan. Walls and distance cost speed. A cable is faster and steadier.
- Your disk or device is the bottleneck. Very fast lines can outrun a slow drive.
If you only see a fraction of your plan, run the speed vs plan checker. To understand megabits and megabytes, read Mbps vs MB/s.
About the example sizes
The sizes in the table are typical round figures, not exact. Game and movie file sizes vary by title and quality, so use the size shown by the store or app for the best answer. You can type any size above.
About this tool
The calculation runs in your browser. If you press “Use my last speed test”, it reads the result the CHECKiOX speed test saved in your own browser. “Measure my speed now” downloads test data from our server for a few seconds, the same way the main speed test does.
Frequently asked questions
How long does it take to download 50 GB?
At 100 Mbps, 50 GB takes about 1 hour 14 minutes in practice, and about 67 minutes at best. At 500 Mbps it takes about 15 minutes in practice. Use the calculator above for your own speed.
How do I calculate download time?
Multiply the size in gigabytes by 8,000 to get megabits, then divide by your speed in Mbps. The answer is in seconds.
Why is my download slower than my internet speed?
The server may limit speed, other devices may be using your line, Wi-Fi may be weaker than your plan, or your disk may be slow. A wired connection and a quiet network give the best result.
What is the difference between Mbps and MB/s?
Mbps means megabits per second and is how internet plans are sold. MB/s means megabytes per second and is how downloads are usually shown. One megabyte is eight megabits.
Does this tool use my data?
Only the Measure my speed now button does, because it downloads test data for a few seconds. Typing numbers and using your last speed test result use no data.
Related tools and guides
- Internet speed test: measure your download speed.
- Mbps vs MB/s: megabits and megabytes explained.
- Data usage calculator: estimate monthly gigabytes.
- Speed vs plan checker: are you getting what you pay for.