Decoding Dates and Numbers on Packaged Foods

Reading food label
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If you’re confused by all of the random numbers printed on canned, boxed, or packaged food items, don’t worry, you’re not alone! Here are some tips to help you decode those numbers and decide what is the best course of action to take.


What do the dates mean?

Since there is little federal regulation on product dating, the format may differ for each company that voluntarily chooses to include such dates. Here are a few dates in particular that you should pay attention to:

  • “Best if used by/best before”: eat the item by this date in order to ensure best flavor and quality. The food item is safe to consume a little while after peak freshness.
  • “Use by/before“: similar to the “best if used by/best before” date, this date indicates the last day the item will be at its peak quality. After this date, product quality (i.e., color, flavor) will gradually deteriorate. Since this date is similar to an expiration date, it is advised to discard the item past this printed date.
  • “Sell by”: indicates the last day the manufacturer can have the item displayed for sale. While this date is less of a concern for canned foods due to their long shelf-life, it is helpful for rotating cans and making sure that older items are eaten first.

Expiration Date
Photo by: Rich Pedroncelli

Should I be concerned about other product codes?

Along with various printed dates, U.S. food companies will include a “lot code”  on their products. A lot code is simply a series of numbers that allows manufacturers and distributors to rotate their stock and identify a specific batch of food items in the event that a recall occurs. Since it does not indicate product quality nor safety, it isn’t necessary to pay close attention to.

Tips for food storage and shelf-life:

  • Before storing a canned/boxed/packaged item, be sure to mark the date, month, and year of purchase somewhere on the package that is clearly visible.
  • Practice “first in, first out.” Arrange non-perishable items so that the older ones are in the front and can be eaten first. Newer items should be placed in the back and be brought up to the front once others are consumed.
  • If you are unsure of a product’s shelf-life, try searching online for the product name and company. A company’s website may have information provided in their Q&A section. If not, click on the company’s “contact us” to find a hotline number, mailing address, or e-mail address.


Henneman A. January 2005. Decoding Food Products and Dates. University of Nebraska Cooperative Extension in Lancaster County. Retrieved from

Institute of Food Technologists. Food Storage and Shelf Life. Retrieved from Expiration Dates: Should You Pay Attention? Retrieved from