Members of the platform have expressed outrage after an update resulted in listings displaying inaccurate size information.
The popular resale platform has revised its sizing categories for female and kids' apparel without notifying every member regarding the update.
Countless users and merchants are expressing on platforms claiming that product pages now present a modified sizing category versus the original listing as a result of the reclassification.
The company said the new system was more in line with other platforms.
It has advised users to check their listings and adjust the sizing manually where appropriate, causing user dissatisfaction.
Before the change, the measurements included one number and one letter, such as S/8 or M/10.
The updated approach includes an alphabetical indicator and numerical range like S/UK 8-10.
For certain items, the sizing has been recategorised - for example a size L was previously a 12 but is now a UK 16-18.
A fashion influencer, who produces content about larger sizing, stated the update "complicates both purchasing and selling".
"Few clothing companies classify XL as 20-22," the way the service now categorizes.
Another user, based in Glasgow, explained products she uploaded on Vinted with size 14 labels were showing in the marketplace as larger sizing 20-22.
"Should someone sized 20-22 purchase these they're going to be very disappointed," she stated.
Charlotte Lunn, from Derby, stated she felt frustrated 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 for me since losing part of my income," she explained.
The app has more than 100 million members, with 18 million British users.
It has become a favored option versus similar marketplaces including eBay and Depop.
This is not the initial instance when a surprising modification on the platform has faced criticism: previously, the service retracted a modification to its shipping options due to shopper criticism.
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