Bandwidth Calculator
Calculate
Size unit
Speed unit
TCP/IP, Wi-Fi and encryption typically leave 85–95% of the rated speed for data. Use 0 for the theoretical figure.
Transfer time
1 h 14 min 4 s
50 GB = 400.000 gigabits, sent at 90.00 Mbps of usable throughput.
Speeds are decimal (1 Mbps = 1,000,000 bits per second) and there are 8 bits in a byte, so a 100 Mbps line moves at most 12.5 MB per second.
Work out how long a download, upload or backup will take at a given connection speed, or the speed you need to transfer a file in a set time. Handles decimal and binary units (GB and GiB), bits and bytes, and protocol overhead.
Formula
Worked Example
50 GB is 400 gigabits. With 10% lost to protocol overhead, 90 Mbps carries the data, so it takes 400,000 ÷ 90 = 4,444 seconds.
Frequently Asked Questions
What's the difference between Mbps and MB/s?
Mbps is megabits per second and MB/s megabytes per second; a byte is 8 bits. A 100 Mbps connection moves at most 12.5 MB/s, which is why a download meter shows a number about eight times smaller than the advertised speed.
Why is my download slower than my plan's speed?
Protocol overhead (TCP/IP, Wi-Fi and encryption) typically takes 5–15% of the rated speed, and Wi-Fi signal, a busy network or a slow server can limit it further. Advertised speeds are also the maximum under ideal conditions.
What is the difference between GB and GiB?
A GB (gigabyte) is 1,000,000,000 bytes and a GiB (gibibyte) is 1,073,741,824 bytes, 7.4% more. Drive makers use GB, while Windows reports GiB but labels it GB, which is why a 1 TB drive shows about 931 GB.