Download Time Calculator
Enter a file size and your connection speed to see how long a download takes, with an efficiency setting for real world conditions.
How to use the Download Time Calculator
- Enter the file size and choose its unit.
- Enter your connection speed and choose Mbps, Gbps or MB/s.
- Adjust efficiency. 90% is a sensible start for a wired connection.
- Read the time, then check the table for other common sizes.
How it is calculated
Size is converted to bytes and speed to bytes per second. Mbps is megabits per second, so it is divided by 8 to get megabytes per second. Effective speed is the rated speed times the efficiency you set. Time is bytes divided by effective speed.
Real downloads rarely hold the rated speed because of protocol overhead, Wi-Fi, other devices on the network and limits at the server. Lower the efficiency to model a weaker setup.
Frequently asked questions
Why is my download slower than my plan speed?
Plans are rated in megabits per second under ideal conditions. Overhead, Wi-Fi quality, other devices and the server all lower real speed.
What is the difference between Mbps and MB/s?
Mbps is megabits per second and MB/s is megabytes per second. There are 8 bits in a byte, so 100 Mbps is at most 12.5 MB/s.
What is the difference between GB and GiB?
A GB is 1,000,000,000 bytes. A GiB is 1,073,741,824 bytes. Stores usually list GB, while some tools show GiB.
Does this work for uploads?
Yes. Enter your upload speed instead of your download speed.