Technology

A lot of people are replying as if OP asked a question. It's a link to a blog post explaining why a kilobyte is 1000 and not 1024 bytes (exactly as the title says!). OP knows the answer, in fact they know it so well they wrote an extensive post about it.

Thank you for the write up! You should re-check the spelling and grammar as some sections had some troubles. I have a sentence I need to go to the post to get, so let me edit this later!

Edit: the second half of this sentence is a mess: "The factors don’t solely consist of twos, but ten are certainly lot of them." Otherwise nothing jumped out at me but I would reread it just in case!

Well it’s because computer science has been around for 60+ years and computers are binary machines. It was natural for everything to be base 2. The most infuriating part is why drive manufacturers arbitrarily started calling 1000 bytes a kilobyte, 1000 kilobytes a megabyte, and 1000 megabytes a gigabyte, and a 1000 gigabytes a terabyte when until then a 1 TB was 1099511627776 bytes. They did this simply because it made their drives appear 10% bigger. So good ol’ shrinkflation. You could make drives 10% smaller and sell them for the same price.

I genuinely don't understand your disdain for using base 2 on something that calculates in base 2. Do you know how counting works in binary? Every byte is made up of 8 bits, and goes from 0000 0000 to 1111 1111, or 0-15. When converted to larger scales, 1024 bytes is a clean mathematical derivation in base 2, 1000 is a fractional number. Your pedantry seems to hinge on the use of the prefix right? I think 1024 is a better representation of kilo- in base 2, because a kilo- can be directly translated up to exabytes and down to nybbles while "1000" in base 2 is extremely difficult. The point of metric is specifically to facilitate easy measuring, right? So measuring in the units that the computer uses makes perfect sense. It's like me saying that a kilogram should be measured in base 60, because that was the original number system.

Stop blaming drive manufacturers

The most scientific shill I've seen in a while

CC BY-NC-SA 4.0

I was confused when I just read the headline. Should be "Why I (that would be you not me) think a kilobyte should be 1000 instead of 1024". Unpopular opinion would be a better sub for it.

Thanks for this article. Unfortunately, you used the word “prefix” when you really meant “unit symbol”. So, “kilo” and “mega” are prefixes, kB and MB are unit symbols. You repeatedly called the latter “prefixes”.

A kilobyte (kB) is 1000 bytes, that's what the prefix kilo means. A kibibyte (KiB) is 1024 bytes (the "bi" in the prefix means base 2 or binary). People often confuse them, but they're similar enough for smaller units, 10^3 ~ 2^10.

Oh and at first, kilobyte was used for both amounts, which is why kibibytes were introduced to fix the confusion, which perhaps was a bit late anyway.

Because a kilo is 1000. That's why you have kibi, mebi, gibi binary prefixes for those times where 1024 (power of 2's) matter.

I know it's already been explained but here is a visualization of why.

0 2 4 8 16 32 64 128 256 512 1024

Kilo = 1000

Byte = Byte

Kilobyte = 1000 bytes

Kibibyte = 1024 bytes

It's a scam by HDD makers to sell less storage for more money.

Because SI prefixes are always powers of the base. Base 10 is the most common, but that's more human psychology that math.

I suggest considering this from a linguistic perspective rather than a technical perspective.

For years (decades, even), KB, MB, GB, etc. were broadly used to mean 2^10, 2^20, 2^30, etc. Throughout the 80s and 90s, the only place you would likely see base-10 units was in marketing materials, such as those for storage media and modems. Mac OS exclusively used base-2 definitions well into the 21st century. Windows, as noted in the article, still does. Many Unix/POSIX tools do, as well, and this is unlikely to change.

I will spare you my full rant on the evils of linguistic prescriptivism. Suffice it to say that I am a born-again descriptivist, fully recovered from my past affliction.

From a descriptivist perspective, the only accurate way to define kilobyte, megabyte, etc. is to say that there are two common usages. This is what you will see if you look up the words in any decent dictionary. e.g.:

• https://www.dictionary.com/browse/kilobyte
• https://www.merriam-webster.com/dictionary/kilobyte
• https://en.wiktionary.org/wiki/kilobyte

I don't recall ever seeing KiB/MiB/etc. in the 90s, although Wikipedia tells me they "were defined in 1999 by the International Electrotechnical Commission (IEC), in the IEC 60027-2 standard".

While I wholeheartedly agree with the goal of eliminating ambiguity, I am frustrated with the half-measure of introducing unambiguous terms on one side (KiB, MiB, etc.) while failing to do the same on the other. The introduction of new terms has no bearing on the common usage of old terms. The correct thing to have done would have been to introduce two new unambiguous terms, with the goal of retiring KB/MB/etc. from common usage entirely. If we had KiB and KeB, there'd be no ambiguity. KB will always have ambiguity because that's language, baby! regardless of any prescriptivist's opinion on the matter.

Sadly, even that would do nothing to solve the use of common single-letter abbreviations. For example, Linux's ls -l -h command will return sizes like 1K, 1M, 1G, referring to the base-2 definitions. Only if you specify the non-default --si flag will you receive base-10 values (again with just the first letter!). Many other standard tools have no such options and will exclusively use base-2 numbers.

This is the stupid af.

This whole mess regularly frustrates me... why the units can't be used consistently?!

The other peeve of mine with this debacle is that drive capacities using SI units do not use the full available address space (since it's binary). Is the difference between 250GB and 256GiB really used effectively for wear-levelling (which only applies to SSDs) or spare sectors?