Networking
Bandwidth Calculator
Estimate transfer time, required speed, or transferable data size. Everything runs locally in your browser.
Inputs
Tip: internet plans are usually advertised in Mbps (megabits per second), while file sizes are usually MB/GB (bytes).
Uses 100% efficiency by default. Show advanced to account for protocol overhead and real-world throughput.
Result
How long should this transfer take?
Transfer time
1m 20s
Assumes 100% efficiency of the advertised speed.
Seconds
80 sec
Minutes
1.33 min
Hours
0.02 hr
Quick explanation
The tool converts your inputs into bits, bytes, and seconds, then applies:
- time = (data × 8) ÷ (speed × efficiency)
- speed = (data × 8) ÷ (time × efficiency)
- data = (speed × efficiency) × time ÷ 8
How it works
Converts your data size, advertised link speed, and optional efficiency into either transfer time, required speed, or transferable data. All math stays in the browser.
- Advertised Mbps are bits per second; file sizes are usually bytes.
- Efficiency accounts for protocol overhead and Wi-Fi/ISP variability.
Quick examples
Set efficiency to match real-world throughput.
Mini FAQ
Why is my result slower than advertised?
Ads quote ideal line rate; overhead and Wi-Fi reduce it.
Should I use Mbps or MB/s?
Use Mbps for link speed; file sizes stay in MB/GB.
What does efficiency mean?
It is the percent of advertised bandwidth you actually get; 85–95% is common.
Related tools