Mercari displays listings as squares on phones, and most browsing happens on small screens. Drop your photos below to resize to 1080 × 1080 — consistent, sharp thumbnails, compressed to keep the app fast.
On iPhone/iPad, "Download all" may open the images instead of saving a ZIP — save them one by one from the preview (long-press → Save to Photos / Files).
Mercari's guidelines are loose, but the app's square-first layouts reward a consistent 1080 × 1080 export. That is also the practical ceiling: sending a 4000px original just gets downsampled, while a pre-sized file arrives sharper.
Clean, uncluttered backgrounds perform best on Mercari — its search results are small thumbnails where busy scenes become noise. Pad mode with a neutral colour keeps the item readable at thumbnail size; Crop keeps it large when the background is already clean.
One thing most sellers get wrong: every one of these platforms re-compresses your photo on upload — Vinted re-encodes around quality 75, Depop around 80, Poshmark around 78 — and downsamples anything above their maximum. A 4 MB iPhone original therefore arrives looking softer than a pre-optimised file. Resizing to the platform's own ceiling and compressing to 250–450 KB before uploading means their pipeline barely touches your photo, and your thumbnails stay crisp.
| Placement | Size (px) | Notes |
|---|---|---|
| Listing photo | 2000 × 2000 | Minimum 2000px on shortest side for zoom |
| Big shop banner | 3360 × 840 | 4:1 desktop header |
| Mini shop banner | 1200 × 160 | Narrow strip banner |
| Shop icon | 500 × 500 | Displayed as a circle |
| Listing landscape | 2700 × 2025 | 4:3 flat-lay friendly |
| Listing portrait | 1500 × 2000 | 3:4 clothing friendly |
Around 1080 × 1080 px square is the practical target — square formats display best in the app, and larger originals simply get downsampled on upload.
Not a requirement, but clean backgrounds win. On small thumbnails a cluttered scene reads as noise, so padding onto a plain colour or cropping tight both help.
Yes — HEIC photos are converted automatically in browsers that cannot decode them, then resized and compressed in the same pass.