This card is 5.5" x 5.5." I used Emma's 'Wow! So Many Candles' stamp set for the sentiment and embossed it with the Tiny Bubbles Cuttlebug embossing folder. I also made a similar card for my great-nephew but his is standard A2 Size of 4.25 x 5.5.
I had made a similar style of a basketball card a while back. HERE is the link if you are interested on seeing it or getting more details on that one.
Sports Mania Cricut cartridge (everything but the Y)
Birthday Bash Cricut cartridge (Y)
My Creative Time stamps - Wow! So Many Candles
Cuttlebug - Tiny Bubbles Embossing Folder