Bits and Bytes Explained: MB, Mb and Download Speeds
Does MB mean the same thing as Mb? The capital letter changes the unit.
1:47 · No narration: the video shows each step as text on screen, and every step is written out below, with buttons that jump the video to it.
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The six points in the video
This is a silent video. The headings, explanations and labels below reproduce the information on screen.
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Step 1: A byte contains eight bits
Read the unit before comparing a file size or a transfer rate.
On-screen labels: One bit; Eight bits; One byte.
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Step 2: B commonly means bytes
File sizes are often displayed using byte-based units.
On-screen labels: Bytes; Kilobytes; Megabytes.
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Step 3: b commonly means bits
Connection rates are often advertised in bits per second.
On-screen labels: Bits; Megabits; Bits per second.
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Step 4: Per second describes a rate
A file size and a transfer rate are not the same measurement.
On-screen labels: Amount of data; Time interval; Transfer rate.
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Step 5: Prefixes need a careful read
Decimal MB and binary MiB use different definitions.
On-screen labels: MB; MiB; Displayed unit.
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Step 6: Allow for real conditions
Overheads and network conditions affect actual download time.
On-screen labels: Actual transferred data; Network overheads; Real download result.
A practical check for your business
Read the unit beside the number before comparing file sizes or connection rates. Record the actual asset and transferred amount so a discussion about size leads to a practical change.
Sources and further detail
Common questions
Does MB mean the same thing as Mb?
The capital letter changes the unit. Check the unit, then compare like with like.
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