Shoppers are voicing their frustration due to a modification that led to products showing incorrect sizing.
The second-hand shopping app has updated its measurement guidelines for female and kids' apparel but did not contact all shoppers about the modification.
Countless users and merchants are posting online stating that platform listings now display an altered size classification than originally posted as a result of the reclassification.
The platform stated the updated approach better aligns with other platforms.
It has advised users to examine their items and update the measurements by hand when needed, which has left users frustrated.
Earlier, the sizes had both a single numeric size and a letter, like S/8 or M/10.
The updated approach includes a letter with a size spectrum for example S/UK 8-10.
In some cases, the sizing has been recategorised - for example a size L was formerly size 12 but now shows as UK 16-18.
Frankie Bridger, who produces content about larger sizing, explained the modification "makes transactions more difficult".
"Rarely do manufacturers list XL as sizes 20-22," which is what Vinted now does.
A different member, based in Glasgow, stated items she posted featuring size 14 markings were appearing on the platform as measurements 20-22.
"Should someone sized 20-22 purchase these they will likely be quite upset," she stated.
Charlotte Lunn, based in Derby, explained she became annoyed due to the update requiring manual adjustment the measurements for "each individual item".
"Personally, this is quite irritating, since I have chronic health issues and platform income has been essential after experiencing income reduction," she explained.
The service features exceeding 100 million shoppers, comprising 18 million UK members.
It has emerged as a preferred choice to second-hand platforms like eBay and Depop.
This is not the initial instance where an unanticipated change on the platform has faced criticism: previously, Vinted reversed a change to its shipping options following member complaints.
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