A column inch is the unit of measurement for the quantity of content in publications (such as newspapers) that utilize multiple columns for each page, each measuring 1 column wide and 1 inch high. Media buyers such as advertising agencies and retail advertisers buy advertising space from newspaper publishers, who would charge a per-column inch rate dictated by the paper’s demographics and circulation. Basically, this means that the more readers there are, the higher the advertisement’s column inch rate becomes.
The standard newspaper ad size is measured according to column inches. An ad measuring a width of 11 picas and a length of 1 inch is equivalent to 1 column inch square. For a newspaper ad that takes up more than a single column, the number of inches high is multiplied by the number of columns to get its column inch size. For instance, if an ad measures 3 columns by 6 inches, it would occupy 18 column inches.
To find out how much the newspaper ad would cost, the number of column inches is multiplied by the rates of the newspaper. If the publisher is charging $10.00 per-column inch, the ad from the example given above would cost $180.00; that would be 18 column inches times $10. Ads taking up more than 1 column also come with a small extra space situated between the columns. These spaces are referred to as the gutters, and they range in size from roughly 10 points to around 1 pica wide. Also, many newspapers would charge for an additional column if the ad spreads over to 2 facing pages, or what is referred to in newspaper terminology as a double truck.
In reference to the size of a newspaper ad, those who work in the newspaper and advertising industries would have a tendency to mention it in shorthand. Using the same example as previous, a 3 columns-wide by 6 inches-high ad would be referred to as merely 3 by 6. This would of course be confusing to one who is not versed in newspaper jargon, mistaking the ad’s size for 3 (width) by 6 (height) in inches when its actual size is really approximately 5.5 by 6 inches. In written form, the “by” is replaced with an “x” when talking about size in inches, to distinguish it from column inches. Nonetheless, it is understood by newspaper professionals that a column inch’s first number is its column width, while the second is its inch height.