Size, resolution and file limits

Three numbers decide whether a listing photo is accepted and whether it looks good: pixel dimensions, file size, and how much the original had to be stretched. They pull against each other, and the useful skill is knowing which one to give ground on.

Size for the zoom threshold, not the minimum

The minimum a marketplace accepts and the size at which it becomes *useful* are different numbers, and the gap is large. eBay accepts 500 px on the long side but only enables zoom at 800 px. Amazon accepts 1000 px and enables zoom at 1600 px. Shopify needs more than 800×800. A photo sized to the minimum publishes fine and then silently loses the feature that lets a buyer inspect what they are buying. Sizing to the zoom threshold — or to the preset's frame, which already sits above it — costs nothing and is the single highest-value setting on this page.

Upscaling has a ceiling

You cannot invent detail that was not captured. Enlarging a 600 px photo to a 2000 px frame stretches it more than three times, and while the file now satisfies the dimension rule, the result is visibly soft — buyers read it as a low-effort listing even if they could not say why. The app measures the stretch factor and warns above **2.5×**, which is roughly where softness becomes obvious at listing sizes. Below that, upscaling is usually fine. Above it, the honest answer is to reshoot rather than to enlarge, and the AI upscale is the middle path when reshooting is not possible.

JPEG or PNG

For a photograph of a product, JPEG at quality around 0.9 is the right default: the compression is designed for photographic content and the artefacts are invisible at listing sizes. Use PNG in exactly one case — when you need **transparency**, for a catalogue or a composite where the background will be supplied later. PNG of a photograph is typically several times larger with no visible gain, and on Etsy's 1 MB cap that difference alone is the difference between fitting and not. Marketplaces that require a white background will not accept a transparent file at all, so PNG is a secondary-image and catalogue format here, not a main-image one.

Fitting a large frame into a small cap

Etsy is the case that forces the issue: 2000 px on the short side and 1 MB total. The lever is JPEG quality, not dimensions — dropping from maximum to around 0.9 typically halves the file with no visible change, and the preset already does that. If it still does not fit, the usual culprit is a noisy background, since JPEG spends bits on noise. A clean white background compresses far smaller than a photographed one, which means removing the background helps the file size as well as the rule compliance. Cropping tighter helps too, and that is the same lever as the fill ratio.