A Dunkin’ customer has revealed the surprising reason why some stores have height charts on the door. 

Earlier this month, a TikTok user named Jocelyn, who goes by the username @officialjuice93, posted a video from inside a Dunkin’ location. 

In the clip, Jocelyn wrote: "Tell me your Dunkin has been robbed with out [sic] telling me they’ve been robbed… I’ll go first."

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The video then pans over to the entrance of the store, where there are lines with height markers up the side of the door. 

Those height markers are intended to help employees and other witnesses gauge the height of any possible criminals, according to a 2012 report from Slate.

Since it was posted, the five-second TikTok video has been viewed more than 451,400 times as of Monday morning. 

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Many people who commented on the clip seemed surprised to learn the real reason behind the height charts. 

"I was today years old when I learned that’s not to see how tall you are for fun," one person wrote. 

A Dunkin' Donuts storefront

A Dunkin' customer revealed that some stores have height charts on their doors to help witnesses measure the height of any potential criminals. (iStock)

"WAIT THATS WHAT THATS FOR?!?!" someone else commented. 

Another person wrote: "I had no idea that’s what it was for."

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Other commenters were less surprised. 

"Yup," one person wrote. "Alot [sic] of places (such as banks) have them so they can get a height description of the subject for the wanted posters/news.. etc!"

"Huh and I thought these were universal," someone else commented. "Where I am they’re literally at every establishment with a register."

Another person said: "I’m from the suburbs in the Midwest and this is pretty common in fast food places. Always thought it was just standard practice."

Meanwhile, another commenter joked: "I’m bringing a man here on a first date."

Fox News reached out to Dunkin' for a comment. 

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