Shoppers are voicing their frustration following a change that caused products showing incorrect sizing.
The popular resale platform has altered its sizing categories for female and kids' apparel without notifying all users about the change.
Countless users and merchants have taken to social media claiming that product pages now present an altered size classification than originally posted because of the remapping.
The company said the revised method more closely matches other platforms.
The platform has recommended to examine their items and adjust the sizing manually if necessary, which has left users frustrated.
Previously, the sizing featured one number and one letter, like S/8 or M/10.
The updated approach includes an alphabetical indicator and numerical range such as S/UK 8-10.
For certain items, the size labels have been reassigned - like an L measurement was previously a 12 but currently displays as UK 16-18.
One content creator, who makes TikTok content about plus-size fashion, stated the update "complicates both purchasing and selling".
"Rarely do manufacturers list XL as sizes 20-22," the way the service now categorizes.
Another user, from Glasgow, said garments she listed on Vinted with size 14 labels were showing in the marketplace as measurements 20-22.
"If anyone [who is] size 20-22 buys them they may become frustrated," she stated.
A different user, based in Derby, said she had been left angered because the modification necessitated personal updates the sizing for "all her products".
"This situation is especially annoying, since I have chronic health issues and selling on Vinted has been paramount for me since losing part of my income," she stated.
The platform boasts over 100 million shoppers, including 18 million in the UK.
It has emerged as a preferred choice to second-hand platforms like eBay and Depop.
This isn't the first time when a surprising modification within the service has received backlash: last year, the service retracted a modification to its shipping options after backlash from users.
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