Bandwidth calculator
Work out how long a download takes at your connection speed, or how much data a connection moves in a set time.
About this calculator
Enter the file size and your speed to find the download time. Allow some overhead because real connections never reach their headline speed.
The second panel works out how much data a speed moves over a number of hours.
Measurements and terms explained
- Mbps
- Megabits per second. Internet plans are advertised in this unit.
- MB/s
- Megabytes per second. File downloads are often shown in this unit. 1 MB/s = 8 Mbps.
- Overhead
- Data used by the network itself rather than the file, often 5 to 10%.
- Gigabyte (GB)
- 1,000 megabytes in this calculator, the way storage is sold.
Common questions
Why is my real speed lower?
Network overhead, Wi-Fi quality and busy servers all take a share.
What is the difference between Mbps and MB/s?
There are 8 megabits in a megabyte, so 100 Mbps is about 12.5 MB/s.
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