Factory formatetd micro SD appears smaller then expected

[countryboyz]

wow good answer. very well explained

[Joshike]

When comparing different manufacturer "2GB" flash cards, there often appears a difference of some MB.
Even the same manufacturer cards size may differ in size.
As a result you may buy 2 "equal" Kingston SD cards and map fits to one but not to second one ...
That was the case - maps expected to fit to all 2GB SD card, failed because these Kingston SD card was undersized by some megabytes and one had to use Sandisk 2Gb card instead.
And at this case there is nothing to do how operating system translates size, when one is smaller then other.

[nobadwords]

Manufacturers use marketing trick to sell sd card like 2GB, even they don't have capacity 2GB, cause OS see it like 1.8 - 1.9 GB

[JohnEP]

"My hard drive, USB stick, flash memory, phone memory, etc. are all smaller than the package says" This has been an ongoing subject for as long as 30 YEARS. Binary vs decimal and formatted vs unformatted is the reason. Been that way since the 1st 5 MB hard drives came out for the IBM PC. Just overbuy memory size, there is always something you can put into the extra storage space like songs or photos of the kids. Its not like 8Gb costs a hell of a lot less than 2 GB these days...