Hello and welcome to another post. Let’s look at why microSD cards do not contain as much capacity as advertised.

A microSD card is an external or secondary storage device that can be inserted into a smartphone. It’s primary purpose is storage of files.

The amount of space that a storage device has is called it’s storage capacity. In many cases, a lot of these storage capacities are wrongly reported. The actual storage capacity is lesser than the advertised storage.

Why is that?

Why microSD cards do not contain as much capacity as advertised

There are two main reasons why:
1. GB vs GiB
2. File system overhead

GB vs GiB
Now this first thing you need to know is that the way we calculate storage capacity and the way computers calculate capacity are very different.

To us regular people…

1KB = 1000B
1MB = 1000KB = 1000^2B
1GB = 1000MB = 1000^3B
1TB = 1000GB = 1000^4B

It makes sense because humans count and calculate in decimal (that is to the power of 10).

Computers on the other hand do not count or calculate to the power of 10. Instead they use binary (that is to the power of 2).

So using computer logic and binary

1KiB = 1024B
1MiB = 1024KB = 1024^2B
1GiB = 1024MB = 1024^3B
1TiB = 1024GB = 1024^4B

The ‘i’ is inserted to let the reader differentiate between the capacity calculated by computers (in binary) and the capacity calculated by humans (in decimal).

So 1MB =/= 1MiB

So now that we are armed with this knowledge, let’s put it into real life practice.

I have a class 10 32GB SDHC card. Since it’s size is 32GB in human language, what is the actual size in machine language?

Let’s turn to mathematics for this one.

To convert from GB to GiB

Divide (1000³ / 1024³), the answer is 0.931323.

Use the answer to multiply 32GB.

32 × 0.931323 = 29.8GiB

So you can clearly see that my 32GB memory has magically become 29.8GB.

Let’s move on to the second reason.

File systems
The file system as I have already extensively explained (please check the blog) is a system used to arrange files on a microSD card or computer storage.

The file system on my microSD card was definitely fat32 from the factory but I have formatted it using Android. This file system logic or code will also occupy a certain amount of space on the microSD card.

It is very small, yes but I can not boldly state the actual size. This will further reduce the space available on the microSD card.


So let’s crosscheck our science and maths with real life to see if it’s true…

Drumroll….

See image before continuing.

My 32GB SDHC card is actually 29.52GB.

TADA!

You can see that 29.52GB is not as sexy as 32GB for advertising. I don’t think I need to tell you the one that the company chose to advertise.

For your affordable microSD cards contact my oga Jboixxx. My SD card when I dey use since 2019 from RN7 to RN9 Pro, na e hand I buy am. Still going strong till tomorrow as you can see in the photo below.

https://www.nairaland.com/3880817/xiaomi-thread-store/1592#116398408

Even in computers its the same thing 1tb turns to 930gb

No wonder my OTG Drive has 15gb in it instead of 16gb.

Chaos14:
Even in computers its the same thing 1tb turns to 930gb

Very correct! 1TB = 931GB (actual size)

IamBabsjnr:
No wonder my OTG Drive has 15gb in it instead of 16gb.

Exactly. 14.9GB actual size.

jboixxx:
Spot on, bro.
The disparity between advertised and real capacities has always been an issue with some clients. Some people don't know the technicality behind the disparity. This is a good write up, as always.

You forgot to add that "memory cards don't come with antivirus" too

Antivirus na software. That customer need two strokes of Oroma cord.

atheistandproud:


Antivirus na software. That customer need two strokes of Oroma cord.

lol. 'Oroma'...similar to how we say 'oranges' in igbo.

TwoFourSeven:
lol. 'Oroma'...similar to how we say 'oranges' in igbo.

Yeah. I had a friend named Ihioma in the early 00s. She just came from the East and she would call orange as óh-range.

It made laugh all the time now it's just normal to me.

atheistandproud:


Yeah. I had a friend named Ihioma in the early 00s. She just came from the East and she would call orange as óh-range.

It made laugh all the time now it's just normal to me.

your friend Iheoma is an 'mgbeke'

Great content! Nice