Bits to bytes costs a factor of eight

Divide advertised Mbps by 8 for ideal MB/s — a 100 Mbps link is about 12.5 megabytes per second at full throttle.

Why it works

ISPs sell megabits; file sizes are megabytes. Protocol overhead and Wi-Fi mean real transfers run below that ideal.

Do it exactly

Estimate with the rule, then check it against the calculator that models it properly.

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More in Computers

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Why is my download speed an eighth of my Mbps?

Divide advertised Mbps by 8 for ideal MB/s — a 100 Mbps link is about 12.5 megabytes per second at full throttle. ISPs sell megabits; file sizes are megabytes.

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