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I needed to figure out how many requests could be made with 1000 GB of traffic if each request took 1MB on average. I quickly did the math on paper, and then as a second thought plugged it into Google. To my surprise, Google's answer is different than mine.

My way:

1,000 gigabytes = 1000*1024*1024*1024 bytes

Divide by 1 megabyte = 1024*1024 bytes to get:

(1000*1024*1024*1024)/(1024*1024) = 1,024,000


The Google Way:

1000 gigabytes / 1 megabyte

Output: 1,000,000


Am I wrong, or is Google wrong?

bertieb
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Nate
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2 Answers2

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Neither of you are wrong, you just asked Google a different question from your actual question. If you had explained to Google that you meant GiB and MiB, it would have given the answer you expected.

Try this: 1000 GiB / 1 MiB

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This is a topic that has been heavily debated, and popularized by hard drive manufacturers (and Wikipedia multiple times). There are two sets of standards for binary prefixes, which pretty much contradict each other. JEDEC uses KB, MB and GB while the IEC uses KiB, MiB and GiB. Here, powers of 1024 are used.

For decimal prefixes (IEC), powers of 1000 are used. Linux, Mac and Google use the 1000 powers when representing KB, MB and GB, while Windows (and Bing) use the 1024 powers for representing KB, MB and GB.

Outside of a small niche, the IEC binary prefixes will seldomly be used. It's worth noting that is was only until recently Google showed that 1024 bytes in to 1 KB.

It's worth noting that the prefixes are used for different things. A 10 Mbps connection is 10,000,000 bits per second a 1.44 MB floppy is 1,400,000 bytes.

Justine Krejcha
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