Shoppers are voicing their frustration following a change that caused listings displaying inaccurate size information.
The second-hand shopping app has updated its sizing categories for female and kids' apparel but did not contact every member regarding the update.
Many shoppers and sellers are expressing on platforms stating that platform listings now display a different size category compared to what was initially listed due to the recalibration.
The company said the new system was more in line with comparable marketplaces.
The platform has recommended to review their products and adjust the sizing manually when needed, which has left users frustrated.
Previously, the sizes had both numerical and alphabetical indicators, for instance S/8 or M/10.
The updated approach includes an alphabetical indicator and numerical range like S/UK 8-10.
For certain items, the size labels have been reassigned - such as a large size was previously a 12 but currently displays as UK 16-18.
Frankie Bridger, who makes TikTok content about plus-size fashion, explained the modification "makes transactions more difficult".
"Not many brands say XL is a 20-22," which is what Vinted now does.
A different member, located in Scotland, stated items she posted on Vinted with size 14 labels were displaying on the service as size 20–22.
"Should someone sized 20-22 purchase these they may become frustrated," she stated.
Charlotte Lunn, from Derby, explained she became annoyed due to the update requiring manual adjustment the sizes on "every single listing".
"This situation is especially annoying, because of my ongoing medical condition and Vinted sales have been crucial following partial earnings loss," she explained.
The service features exceeding 100 million users, with 18 million British users.
It has emerged as a preferred choice versus similar marketplaces including eBay and Depop.
This is not the initial instance that an unexpected update to the app has proved unpopular: earlier, the service retracted a modification regarding delivery choices after backlash from users.
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