Unit price labels can be confusing

Picture this: You're at the supermarket trying to find the best deal on AA batteries for your flashlight, so you check the price labels beneath each pack. Sounds pretty straightforward, right? But how can you tell which pack is cheaper when one is priced per battery and another is priced per 100?

Welcome to the perplexing world of unit pricing. Eight in 10 Americans rely on those labels to determine the most economical brands and package sizes. In theory, they're the easiest way to see whether purchasing a 59-ounce container of orange juice is cheaper than buying a quart.

Consumers can be confused or even misled when unit-price labels are inconsistent or unclear. And that's often the case. There are no federally mandated, standardized requirements for unit pricing as there are for Nutrition Facts labels. They're actually exempt from the Federal Trade Commission's Fair Packaging and Labeling Act.

"Neither industry nor state government perceives a big problem with unit pricing in the marketplace," says David Sefcik, a weights and measures expert for the National Institute of Standards and Technology (NIST), an agency in the Department of Commerce. "It's an issue that hasn't generated a lot of consumer complaints because many people simply don't know what they're missing, and that improvement is needed."

The major chains feel no need to change without pressure from consumers, he adds.

Learn about America's best supermarkets—and worst, and check our buying guide and Ratings of dozens of grocers, broken down by region.

Consumer Reports last uncovered widespread inconsistencies in unit-price labels in 2012, when we worked with NIST to create an ideal label.

Today, unit-price labels remain essentially voluntary. Only nine states and the District of Columbia have mandatory regulations, but they differ from each other. Ten other states have voluntary regulations that follow recommendations from NIST.

We recently shopped at nine stores near our headquarters in Yonkers, N.Y., and found a mixed bag in terms of content and clarity as well as layout and legibility.

Some unite price labels had type as tiny as 0.22 inch, unreadable for impaired or aging eyes. Others had different ways of comparing the same products. We found:

• Furniture polish priced by the pound and by the pint.
• Batteries and toothbrushes priced "each" and "per 100."
• Salad dressing priced by the pint and by the quart (see above).
• Toilet paper priced by "100 count," though the "count" (a euphemism for "sheets") differed in size and number of plies depending on the brand.
• Dental floss priced per pack, though containers varied widely in capacity, from around 30 yards to more than 100.

Since 2012, Sefcik has gathered input on unit pricing from academics, consumer watchdog groups, officials, retailers, and trade associations. He compiled their recommendations into a guide, "A Best Practice Approach to Unit Pricing" (PDF), that is the first comprehensive primer on the layout, design, and presentation of unit-price labels. It was released earlier this year. His goal is to encourage companies to follow the standards, eliminating ambiguities once and for all.

"Now that retailers have a national set of guidelines of how to implement unit pricing in the most effective way, there is no excuse or reason for them not to provide it," says Edgar Dworsky, a former assistant attorney general for consumer protection in Massachusetts and a founder of ConsumerWorld.org. "It is part of good customer service."

When comparing unit-price labels, make sure that you're really comparing apples to apples. If some apples are sold by the piece and some by the pound, you might need a scale or calculator to determine the best deal. And if unit-price labels are inaccurate or illegible, don't suffer in silence: Tell a store manager.