Bar Code Color Selection

Bar codes have been used in some form or another since the first patent application was filed in 1949. The first commercial application was in a Marsh's supermarket in Troy Ohio in 1974. A pack of Wrigley's gum was the first item to be scanned and purchased using a bar coding system.

Today over ten trillion bar codes are printed every year. They are used on everything from packs of gum to a jet airliner. They are even used on ear tags for tracking livestock. Bar coding is an efficient and cost effective way to manage and track inventory throughout the lifespan of the product.

Because of the wide use of bar codes, and the importance of accuracy and speed, it is extremely important to choose your code color carefully. Along with the color of the code, you need to consider the color of the substrate or background the code is being printed on. If you choose the wrong color code, or the wrong color substrate you could render the bar code unreadable. An unreadable bar code means the data will need to be hand entered instead of being automatically read by a scanner. Hand entering bar code data equates to loss of time and productivity.

All bar code scanners are designed to read codes that have a high contrast to the substrate on which they are printed. If the codes are printed with a high contrast, the operator using the scanner will have a much easier time scanning the codes, thus resulting in higher productivity. That is assuming of course that the bar code is printed within specifications for size and other factors. But that is another discussion.

The most preferred color for printing a bar code is black. However, it is not always possible to use black. If black is not available, the next choices would be other dark colors like dark blue or dark green. Never use red for the code if your scanner emits a red beam of light. The red color is invisible to the scanner's optical system because of the red illumination or laser beam. The only time you would ever consider using red would be if you have a custom scanner. I have seen some scanners that do not use red illumination, thus allowing them to read bar codes printed in red. But those scanners are few and far between. Other colors to avoid are light colors, like yellow, orange and pink.

White is the preferred color for the substrate or background that the code is printed on. White has the highest reflectivity available and will result in optimal contrast between the code and the background. If you can not use white, then use another color that is very light or invisible to the scanner. Yellow and red are two good colors to choose as a substrate. Yes – red is a good color. Remember that red is invisible to the scanner because of the scanner's red illumination system.

If you really want to maintain efficiency, accuracy and productivity in your data collection system, ensure you follow these simple rules on color choices for the bar code and the substrate. Choosing high contrast colors will make everyone's job much easier.