Special-shaped cards refer to credit cards with irregular shapes. Standard cards are cards of international standard size, with dimensions of 85.5mm×54mm×0.76mm. Nowadays, many kinds of "weird" cards have appeared in various countries around the world. We call these cards alien cards. These shape cards, such as squares, rectangles, triangles, ovals, etc., are called "non-standard cards"; some special-shaped cards in the shape of animals and dolls are called "quasi-abnormal cards".

Special-shaped cards are usually non-international standard cards customized according to individual needs. The thickness and size of the cards are different from standard cards. It is reported that the basic thickness of special-shaped credit cards is 0.3mm, 0.5mm, 0.6mm, 0.76mm and other types. The card size is also different from the size of regular cards. Personalized patterns or commemorative pictures can be used on the card cover.

However, due to the abnormal size of the special-shaped card, there are some restrictions on its use. Therefore, in order to ensure that cardholders can enjoy all the services of credit cards, banks will also apply for a standard card when applying for special-shaped cards to ensure that they can still enjoy credit card services even if the special-shaped cards cannot be used.