In 1970, the world was asked the question, “How many licks does it take to get to the Tootsie Roll center of a Tootsie Pop?” The question was posed in an animated commercial (see below) in which a boy asks several animals if they know the answer. Each animal confesses ignorance, referring the boy to another animal. This continues until Mr. Owl offers to find the answer for himself. He takes three licks before giving in to temptation and biting into the candy snack. The commercial ends with “How many licks does it take to get to the Tootsie Roll center of a Tootsie Pop? The world may never know.”

More than fifty years have passed since the question was posed, but the absence of a definitive answer suggests there may be some truth in saying the world may never know.

Researchers, ranging in credentials from preschool students to scientists have attempted to find an answer to the elusive question. The results are far from conclusive:

• Engineering students at Purdue University built a machine that would simulate the licking effect of a human tongue. Their experiments concluded that it takes an average of 364 licks.
• Twenty Purdue University students, using their non-mechanical tongues, averaged 252 licks to accomplish the same task.
• A chemical engineering student at the University of Michigan built their own licking machine and concluded it takes an average of 411 licks.
• Mathematicians at New York University used a giant homemade ball of candy and applied fluid dynamics, chemical erosion principles, and chemical analysis to extrapolate that it would take approximately 1,000 licks.
• A group of junior high school students from Swarthmore Schools concluded in 1996 that a range of 70 to 222 licks was necessary, averaging out at 144 licks.
• Bellarmine University students conducted a study, using 130 participants. The results were carefully scrutinized, considering the gender of the participants, the flavor of the Tootsie Pop, and the time of day in which the experiment was attempted, and the amount of time it took to get to the center. They concluded that orange Tootsie Pops are consumed the quickest, regardless of gender or time of day. Males tend to take about the same amount of time to get to the center, but they do so with fewer licks than their female counterparts. The researchers hypothesized that this is due to males generally having larger mouths and tongues. The study also concluded that participants take more time and licks when tackling the assignment first thing in the morning than they do as the day progresses. The study also concluded that the eye color of the participant was not a significant factor in how quickly he or she gets to the center of the Tootsie Pop. A summary of the findings is below. To read the complete report on the study, click here.

Of course, Tootsie Roll Industries produces its product primarily for children, not scientists. It is appropriate that kids should speak into this controversy. Tootsie Roll Industries reports having received more than 20,000 letters from children around the world who believe they have solved the mystery. The reported results range from a low of 100 to a high of 5,800 licks. Most fall within the range of 600-800 licks.

Tootsie Roll Industries answers every letter sent by children. It also sends out a certificate known as “The Clean Stick Award” to everyone who writes, advising how many licks it takes. If you are convinced you know the answer, you can contact Tootsie Roll Industries through its website, or you can download your own PDF version of The Clean Stick Award.

If you produce your own scientific study about your findings, we’d love to share the results. Once we have finally resolved the question of how many licks it takes to get to the center, we’ll turn our attention to figuring out where all the missing socks go on laundry day.