What this tool does
Marketplaces publish hard limits that refuse an upload and softer guidance that does not, and the two get blurred together everywhere. This measures one file against one marketplace and keeps them apart, down to the exact background colour and the fraction of the frame the product actually fills. It also prints the list of things no pixel measurement can reach, because that list is the part incumbents skip and the part that gets a listing rejected.
How it works
The measurable rules are exact rather than approximate. The longest-side minimum and maximum, the shortest-side minimum that both dimensions must clear, the aspect ratio with its tolerance, the file size band, and the format whitelist, read against the file's real MIME type. Animation is detected from the bytes rather than by decoding every frame: a GIF repeats the graphic control extension, a WebP animation carries ANIM, an APNG carries acTL. False there means no marker was found, not that the file is provably a single frame.
The background check is the most useful thing on the page, because it catches a failure no eye can see. Amazon asks for pure white, written as exactly 255, 255, 255, so every sampled pixel in every corner patch has to be that value. A background that looks white and measures 248 to 253 fails, and you cannot see it yourself, which is why the brightest corner is reported alongside the darkest one and the rule is never satisfied by averaging: a handful of 254s must not hide behind a 255.
The fill ratio turns framing from a vibe into a number. The bounding box of every pixel that is not the backdrop is measured, and the product spanning 85% of the frame is 72% of the area, so both numbers are reported rather than one quietly substituting for the other. What counts as the product is still your judgement — a shadow, a reflection and a prop all sit inside that box — but at least the geometry is a measurement and not an opinion.
What this tool cannot check is listed in full, and it is longer than the list of what it can: text overlays, badges, props and staging, logos and the right to use them, watermarks, promotional claims, category rules such as ghost mannequin or jewellery scale, whether the photo is of the variant being sold, and whether the colour matches the real product. It also states where its own figures came from and how well they were verified. Flipkart and Meesho are included and labelled unverified, because no primary source could be read for them and a rule invented from memory is worse than no rule.
Worked example
A 1600 × 1600 JPEG product shot is being prepared for an Amazon listing and an Etsy listing, and it is being rejected.
- Longest side 1600px clears the 500 to 10000 range on both marketplaces
- The file is 0.8 MB, inside the 1MB Etsy ceiling, and image/jpeg is on both format lists
- The corners measure 251, 251, 251 — the darkest corner is 251 against the 255 the rule demands
- The product's bounding box is 1200 × 1200 in a 1600 × 1600 frame, so 56.2% of the pixels, or 75.0% across
The Etsy checks pass. The Amazon pure-white check fails on a background that looks white to everyone involved, and the fill ratio is below the 85% guidance, which is a warning rather than a block. Fixing the backdrop and re-shooting tighter clears both.
Accuracy and limitations
- Marketplace rules change without notice. Each row shows the source and the date it was read, and a stale figure is worse than no figure.
- Amazon's numbers here are marked secondary, read through a search index rather than the seller guide itself. Treat them as consistent rather than confirmed.
- Nothing is asserted at all about Flipkart or Meesho. Their documentation could not be read from outside the seller dashboard, so the figures in circulation disagree and none of them are repeated here.
Frequently asked questions
- Why was my Amazon product image rejected?
- Most often the background, not the size. The main image has to be pure white, written as exactly 255, 255, 255 in every channel, and a backdrop that measures 248 to 253 looks white to the eye while failing the rule. This tool reports the darkest corner value so you can see the number instead of guessing.
- What size should a product image be for each marketplace?
- They differ: Amazon needs at least 500px on the longest side and no more than 10000, Etsy's first photo must clear 635px on both dimensions, eBay sets a 500px floor, and Shopify caps the longest side at 5000. Every row here shows its source and how well it was verified.
- What is the right background colour for a product photo?
- For a pure-white rule it has to be exactly 255, 255, 255, with no tolerance, because that is how the rule is written. A near-white backdrop is the failure this check exists to catch, because nothing in the image itself will tell you it is wrong.
- Can this check whether my photo has text or a watermark?
- No, and that is stated rather than glossed over. Text overlays, badges, props, logos, watermarks and promotional claims are a matter of judgement and of rights, not of pixels, so they are listed as outside what any measurement can tell you.
- Does it cover Flipkart and Meesho?
- They are in the list and labelled unverified, which means nothing is asserted for them at all. Their seller documentation could not be read from outside the dashboard and the figures circulating on secondary sites contradict each other, so check the current requirement in the seller dashboard before you rely on anything.
- Is my product photo uploaded?
- No. The file is decoded, measured and checked in your browser, tab by tab, and never leaves your device. Large files are sampled on a step above about 400,000 pixels so a 24MP shot does not lock the page.