The two standard sizes of playing cards are the poker size and bridge size. Poker-sized playing cards are 2.5 inches wide by 3.5 inches long. Bridge-sized cards are 2.25 inches wide by 3.5 inches long.
Casinos use standard bridge-sized playing cards at many of their tables. These cards are slimmer than poker-sized cards, which makes them easier to handle, shuffle and deal. Poker-sized playing cards are used for most card games. Other sizes of playing cards are also manufactured to suit different uses. Solitaire playing cards are available in a compact size that makes them easy to transport in a purse or bag and measure just 1.75 inches wide by 2.625 inches long. Larger cards are used for performing magic tricks.