how can you test SD cards speed to check

Hi, just wondering how you can test the write speed and so called 'class' of an sd card that I use in my canon d7.

as there are many brands out there that don't print the actual write speed on the card.

and also there are many fraudulent items where they put a label showing a higher speed than it actually is..??

just curious as nome of my cards dont keep up with the camera buffer...

Regards, Sandy

You can test the cards by copying a large file (100MB) to the card using the fasted card reader you can find. Copy the file to the card and count how many seconds it takes to full copy it to the card. Then divide the 100MB through the number of seconds, the result is how many MB per second.
Although this result may not always be accurate because of the card reader/USB slowing it down.

Read this article for more information,
SD Card Speed Test

much appreciated, regards, Sandy