The wrong-size-in-the-title tax
In short
Your title says 'medium'. The buyer searches 'UK 12'. Your listing doesn’t exist to them.
Sizing on Vinted isn't a description thing, it's a filter thing. Buyers don't read 'medium' in your title and decide it's their size. They flip the size filter to a number — UK 12, EU 40, US 8 — and only see listings where the size field matches.
If your title says 'medium' and the size field is empty or wrong, you're invisible to the buyer who'd actually have bought it. Worse: when someone does land on it and the size is off, they message you, the chat clogs up, and you take a chunk out of your reply-rate stat. VintSnap reads the photo and the brand label and fills the size field properly — UK, EU and US numbers all populated, not just one.
Two minutes of pain you stop having.
If your title says 'medium' and the size field is empty or wrong, you're invisible to the buyer who'd actually have bought it.
This note comes from building VintSnapA photo in, a priced Vinted listing out.
See VintSnap