Shoppers are voicing their frustration after an update resulted in listings displaying inaccurate size information.
This online marketplace has altered its sizing categories for women's and children's clothes without notifying every member regarding the update.
Numerous buyers and vendors are expressing on platforms stating that platform listings now display a different size category than originally posted because of the remapping.
Vinted explained the new system was more in line with comparable marketplaces.
It has advised users to check their listings and manually change the size if necessary, causing user dissatisfaction.
Earlier, the sizes had both 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 size labels have been reassigned - like an L measurement used to be a 12 but currently displays as UK 16-18.
Frankie Bridger, who makes TikTok content about plus-size fashion, said the change "makes both selling and buying harder".
"Not many brands say XL is a 20-22," as the platform currently indicates.
Stephanie Gallen, based in Glasgow, stated items she posted with size 14 tags were showing in the marketplace as measurements 20-22.
"Should someone sized 20-22 purchase these they may become frustrated," she said.
Charlotte Lunn, based in Derby, explained she became annoyed due to the update requiring manual adjustment the sizing for "all her products".
"For me this is particularly frustrating, as I'm chronically ill and Vinted sales have been crucial after experiencing income reduction," she said.
The app has more than 100 million users, comprising 18 million UK members.
It has proved a popular alternative versus similar marketplaces including eBay and Depop.
This is not the initial instance when a surprising modification to the app has proved unpopular: earlier, Vinted reversed a change to its shipping options after backlash from users.
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