Members of the platform have expressed outrage due to a modification that led to products showing incorrect sizing.
This online marketplace has updated its measurement guidelines for women's and children's clothes failing to inform all users about the change.
Countless users and merchants are posting online stating that platform listings now display a modified sizing category versus the original listing due to the recalibration.
Vinted explained the new system was more in line with comparable marketplaces.
It has advised users to examine their items and adjust the sizing manually when needed, causing user dissatisfaction.
Before the change, the measurements included numerical and alphabetical indicators, like S/8 or M/10.
The revised method features a letter and a range like S/UK 8-10.
With some products, the measurements have been reclassified - such as a large size was previously a 12 but is now a UK 16-18.
A fashion influencer, who makes TikTok content about plus-size fashion, said the change "makes both selling and buying harder".
"Rarely do manufacturers list XL as sizes 20-22," the way the service now categorizes.
Another user, located in Scotland, explained products she uploaded with size 14 tags were displaying on the service as larger sizing 20-22.
"Should someone sized 20-22 purchase these they're going to be very disappointed," she stated.
A different user, located in England, explained she became annoyed because the modification necessitated personal updates the sizes on "every single listing".
"For me this is particularly frustrating, because of my ongoing medical condition and selling on Vinted has been paramount after experiencing income reduction," she explained.
The app has more than 100 million shoppers, with 18 million British users.
It has become a favored option compared to resale services such as eBay and Depop.
This isn't the first time that an unexpected update on the platform has faced criticism: earlier, the service retracted a modification regarding delivery choices after backlash from users.
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