Shoppers are voicing their frustration following a change that caused items being listed as the wrong size.
The popular resale platform has revised its measurement guidelines for women's and children's clothes failing to inform every member regarding the update.
Many shoppers and sellers have taken to social media stating that platform listings now display an altered size classification than originally posted because of the remapping.
The platform stated the revised method more closely matches similar services.
They have suggested members to examine their items and manually change the size if necessary, which has left users frustrated.
Before the change, the sizes had both one number and one letter, like S/8 or M/10.
The updated approach includes an alphabetical indicator and numerical range such as S/UK 8-10.
For certain items, the sizing has been recategorised - like an L measurement was previously a 12 but currently displays as UK 16-18.
A fashion influencer, who makes TikTok content about plus-size fashion, stated the update "complicates both purchasing and selling".
"Few clothing companies classify XL as 20-22," which is what Vinted now does.
Stephanie Gallen, based in Glasgow, stated items she posted featuring size 14 markings were appearing on the platform as measurements 20-22.
"If buyers measuring 20-22 acquire them they will likely be quite upset," she stated.
Charlotte Lunn, from Derby, stated she felt frustrated due to the update requiring manual adjustment the measurements for "each individual item".
"Personally, this is quite irritating, because of my ongoing medical condition and Vinted sales have been crucial following partial earnings loss," she stated.
The app has more than 100 million shoppers, with 18 million British users.
It has emerged as a preferred choice versus similar marketplaces including eBay and Depop.
This isn't the first time when a surprising modification within the service has received backlash: earlier, Vinted reversed a change to its shipping options following member complaints.
Emma is a cannabis enthusiast and writer with a passion for exploring the benefits and culture of hemp products.