How to use the checker
- Pick the marketplace you're listing on — Amazon, eBay, or Etsy. The rules and thresholds change with the choice, and the spec line under the dropdown shows exactly which ones apply.
- Drop in one photo or a whole batch (up to 20 JPG, PNG, or WEBP files). Nothing uploads; the files are read straight off your disk into the page.
- Read the report card for each image. A fail means the photo breaks a rule the marketplace states; a warning means it is below a recommendation or an estimate found a likely problem. The measured value sits next to each check.
- Apply a fix where one is offered (snap a near-white background to pure white, or flatten a transparent PNG onto white), compare it with your original, and download the corrected file — individually or as a
.zipfor the batch.
What the report actually shows you
Take a common case: an Amazon main image shot in a lightbox. To your eye the background is white. The report card comes back with:
- Pure-white background — FAIL. Only a small share of the edge background is exactly
255,255,255; the darkest pixel is248,249,247. Because the backdrop is near-white, “Snap background to white” is offered. It whitens only near-white pixels connected to the image edge, so white or light parts inside the product are left alone. - Image size — PASS. 2000 × 2000px, over Amazon's 500px minimum and its 1,000px recommendation (the size that enables zoom).
- Product fills frame — WARNING (estimate). The product spans about 71% of the frame; Amazon asks for the product to be 85% of the image. Crop closer, keeping the whole product in frame.
- Edge shadow, added marks, whole product in frame — estimates. These are heuristics: they flag what to look at, and say “check by eye” when they find nothing, rather than claiming a pass.
Snap, crop, re-check — before the photo ever reaches Seller Central. No tool can guarantee a marketplace will accept a photo; ListingLint catches the measurable problems. The full method behind each measurement is in how ListingLint checks your photos.
When it helps most
- Before a first upload, so a launch isn't held up by a silent rejection you can't see.
- After an unexplained rejection, to find the measurable cause fast — work the diagnostic checklist alongside it.
- Before a bulk / flat-file upload, to catch the photo that will fail across 50 SKUs at once.
- When cross-listing, to see whether one hero shot can serve Amazon, eBay, and Etsy or needs a white-background version for Amazon only.
How it compares to the alternatives
- Uploading and waiting for the marketplace to tell you. The slowest loop, and the rejection message is often vague ("image does not meet requirements"). ListingLint gives you the specific value now.
- The eyedropper in Photoshop or GIMP. Accurate for background colour if you know to check the exact corner pixels, but it it won't estimate frame fill or check size thresholds, and there's no batch mode.
- Paid listing-audit or repricer suites. Some include image checks, bundled into a subscription aimed at larger sellers. ListingLint does the image part only, free, with nothing to install and nothing uploaded.
- Background-removal web apps. Great when you genuinely need to cut the product out, but they upload your image and they don't tell you whether you needed to. Check first; only reshoot or cut out if the background is truly coloured.