Not a good one. Here I just follow my camera's instruction as to format it WE MUST DO THAT IN THE CAMERA FOR MAXIMUM COMPATIBILITY.
I own both the Canon t3i and now a t6i.
But there are many fake cards out there and if you can't format it in the camera I worry it's either incompatible or FAKE.
Try https://www.sdcard.org/downloads/formatter/ BUT be sure to format in the camera later.
Tell more about this SD card? Cheap Ebay thing?
I have a Canon Rebel T6 and I recently formatted the sd card following some online instructions. Now, neither my computer nor my camera are able to read the card. does anyone know what might have caused this and/or what to do to fix it? Thank you.