Shoppers are voicing their frustration following a change that caused products showing incorrect sizing.
The second-hand shopping app has altered its sizing categories for women's and children's garments failing to inform all shoppers about the modification.
Many shoppers and sellers are expressing on platforms stating that platform listings now display an altered size classification compared to what was initially listed because of the remapping.
The platform stated the new system was more in line with other platforms.
The platform has recommended to examine their items and manually change the size if necessary, which has left users frustrated.
Previously, the sizing featured a single numeric size and a letter, for instance S/8 or M/10.
The updated approach includes an alphabetical indicator and numerical range for example S/UK 8-10.
With some products, the size labels have been reassigned - like an L measurement was formerly size 12 but now shows as UK 16-18.
A fashion influencer, who makes TikTok content about plus-size fashion, stated the update "complicates both purchasing and selling".
"Not many brands say XL is a 20-22," which is what Vinted now does.
Another user, from Glasgow, explained products she uploaded featuring size 14 markings were appearing on the platform as measurements 20-22.
"If anyone [who is] size 20-22 buys them they will likely be quite upset," she said.
Charlotte Lunn, from Derby, said she had been left angered due to the update requiring manual adjustment the sizing for "all her products".
"This situation is especially annoying, because of my ongoing medical condition and selling on Vinted has been paramount after experiencing income reduction," she stated.
The app has more than 100 million users, including 18 million in the UK.
It has proved a popular alternative to second-hand platforms like eBay and Depop.
This represents another occasion that an unexpected update on the platform has faced criticism: last year, the service retracted a modification concerning shipment methods due to shopper criticism.
