Bandwidth
Names and abbreviations on this page
MDN — MDN Web Docs (formerly Mozilla Developer Network). Reference material for web programming.
Technology terms & practical skills
What it means
In networking, bandwidth describes the data transfer capacity of a connection, commonly stated in bits per second. Actual throughput is the rate achieved in use. Latency is the delay before data arrives; a connection can have high capacity and still feel delayed.
Related skills
Read unitsRecognize that a byte contains eight bits.
Compare performanceSeparate advertised capacity from a measured transfer rate.
Plan shared useConsider simultaneous video calls, downloads and other devices.
An everyday example
A 100-megabit-per-second connection has a theoretical rate of 12.5 megabytes per second before overhead. Actual downloads can be slower because of Wi-Fi conditions, shared use and the sending service.
What to check
A single speed test does not identify every problem. Compare tests at similar times and locations, and consider latency for calls.