Decimal vs Binary in Storage

[rax313]

Hi all,

I have just recently watched Linus's new "As fast as possible" in which he discusses how manufacturers and OS measure drives with either using the "decimal" (1000 bytes approx) and binary kibibyte(?) (1024 bytes) so my question is, is there any way I can measure how much a disk is in decimal or binary?

Example: Let's say an Intel SSD with 180GB, how do I convert this to "binary" since I think manufacturers use the decimal system.

Yea I am terrible in math so I might have missed on how I can figure this out for myself.

The youtube video:

http://www.youtube.com/watch?v=f7H0yXjy6VI

thanks in advance

[Godlygamer23]

You can do it the easy way and use some kind of converter app like MyConvert on iOS.

[Gomenasai]

Its a bit more complicated to figure the "binary calculated decimal" amount because you are trying to read a binary number in decimal. I don't really like to call it binary binary because binary is just 1s and 0s. All you need to know to calculate it is to replace every 1000 with 1024. That is the offset that cuts your drive down by a little bit. There are 1024 bytes in a "kilobyte", 1024 KB in a MB, and 1024 MB in a GB. Its pretty much all the early manufacturers fault for abandoning the correct standard of KiB/KibiByte etc.

 

So, here is the math!

 

Example: How many bytes are actually in my 1TB Drive?

 

Simple, 1TB is 10^12 so 1000000000000 bytes. Now how many "Gigabytes" are in my drive. 

 

Just divide by 1024 everytime.

1000000000000 bytes = 976562500 Kilobytes

976562500 Kilobytes = (rounded down) 953674 Megabytes

953674 Megabytes = (rounded down) 931 Gigabytes

 

Alternatively... you can google a converter...

 

So in response to the OP:

1GB = 10^9

"180GB" = 180000000000 bytes

180000000000 bytes = 175781250 kilobytes

175781250 kilobytes = 171661 megabytes (rounded down)

171661 megabytes = 167.6 gigabytes (rounded down)

[Glenwing]

If the value is in Gigabytes, multiply the decimal value by 0.931 to get an approximation of how it will show up in Windows (binary system).

 

The number is derived from:

 

(1000 * 1000 * 1000)

(1024 * 1024 * 1024)

 

If the value is in Megabytes or Kilobytes, the value you need to multiply by to convert will change.  Just do the above calculation plus or minus more 1000/1024's as needed for each increasing or decreasing order of magnitude.

 

If the value you need to convert is in binary already, do the above calculation upside down, and multiply the storage value by that to get it in decimal.

[bradscoolio]

This video is private for some reason :( I watched it when it was uploaded and was the first to comment on it too, but now I can't see it.

[rax313]

Thank you Gomenasai and Glenwing I can now shop HDD again with confidence

and to anyone interested Glenwing has the TLDR version ^^