📡 Bandwidth Calculator
Enter a file size and a link speed to estimate how long the transfer will take, in a readable hours-minutes- seconds format, along with the megabit and throughput maths behind it.
🌐 File Size vs Link Speed
What is a Bandwidth Calculator?
It answers the everyday infrastructure question: at this link speed, how long will this file take to move? By converting bytes to bits and dividing by throughput, it gives a quick estimate for sizing backups, planning migrations, or judging whether a link is fast enough for a workload.
Use it to plan data movement and set expectations. The number is a best-case estimate for planning — real transfers are slower thanks to overhead and congestion, so verify against your actual links.
❓ Frequently Asked Questions
How is transfer time calculated?
The file size is converted to megabits (a megabyte is eight megabits) and divided by the link speed in megabits per second. So a 1 GB file (8,000 megabits) over a 100 Mbps link takes about 80 seconds. The calculator handles the unit conversions — MB, GB, TB and Mbps, Gbps — for you.
Why do real downloads take longer than this estimate?
This figure is a theoretical best case. Actual transfers run slower because of TCP/IP protocol overhead, latency and round trips, network congestion, packet loss, server limits, and the speed of the disks at each end. Treat the result as a planning estimate and verify against your own links.
What's the difference between MB and Mb?
A megabyte (MB) is eight megabits (Mb). Storage and file sizes are usually quoted in bytes (MB, GB), while network speeds are quoted in bits per second (Mbps, Gbps). Mixing them up gives an answer that's off by a factor of eight — this tool keeps the units straight so you don't have to.