Guide to Index Cards

An index card is a type of heavy paper that is cut to a standard size, often used for recording individual information that can be filed and easily rearranged.  The most common index card size used in the United States is 3-by-5 inches.  Other sizes available include 4x6, 5x8, and ISO A7 (74mm x 105mm). It is commonly white but is also available in colored.  

There are special index card holders with protruding tabs for organizing the index cards.  Index cards are popular for organizing ideas, quotes, references for research, term papers, and for managing free-form information. 

• Plain white index cards provide better visibility because it allows high contrast: the ink against the white background.
• It is the standard for offices, schools, and documentation.

• Colored index cards allow color coding of information for easy organization.
• It gives more life to the monotony of white index cards.
• It is also less likely to show wear or dirt than white cards.
• It is usually available in blue, pink, yellow, orange, and green.
• The color of the ink to be used should contrast the color of the index card or it may not be visible.