Which marketplace specs does my photo already meet?
You already have the photos. This page measures each one against every rule in the library — 51 rules across 18 marketplaces — and tells you, rule by rule, whether the file can be uploaded as it is, with the number that decided it. Nothing is uploaded; the decoding happens in your browser.
- Files never leave your browser
- No sign-up
- 18 marketplaces · 51 rules
Check a photo
JPG or PNG, one file or a batch. Pick them below or drop them on the box.
What this check cannot see
This checker cannot tell whether the background is pure white, whether the product fills enough of the frame, or whether the image carries a watermark or text. Those are the reasons photos usually get rejected, and no pixel counter can judge them.
The page judges four hard numbers only: pixel size, aspect ratio, file size and file format. Whether a marketplace finally accepts a photo is the marketplace's call, not this page's. Treat a pass as "the file meets the numbers we can measure", not as an approval.
The four checks, stated exactly
| Check | Passes when |
|---|---|
| Pixel size | Width and height equal the spec exactly. Where a spec also publishes a minimum width, the required width is the larger of the two numbers — the stricter of the two wins. |
| Aspect ratio | Width ÷ height is within 1% of the spec's own ratio. A 1000×1000 photo matches the shape of an 800×800 spec (and still fails its size); a 1200×900 photo does not match a square spec at all. |
| File size | The real byte count of the file is at or under the published ceiling, compared in KB. Specs that publish no ceiling are not judged on size at all — no row is invented for them. |
| File format | The file must be one of the formats the spec lists. JPG and JPEG are the same format, so either spelling in the spec accepts a .jpg file. One Shopify video spec lists MP4 only: a still photo can never satisfy that row, and it is shown as failing rather than hidden. |
What a result looks like
Every rule gets one line: pass or fail, and the number behind it — "size 1000×1000 px; the spec asks for 800×800 px", "812 KB, over the 100 KB ceiling", "aspect 1.333 against the spec's 1.000: 33.3% off". Failing rows are listed first, because they are the ones you have to act on; the rules a photo already satisfies are folded under their marketplace.
When most rows fail on size
Then the photo has to be resized, and this page is not the tool for that. The batch tool takes a spec, scales proportionally, pads white where the spec wants white and compresses under the ceiling. If the same photo is going to several marketplaces, the all-platforms export writes one file per spec into a single zip. Both run in the browser, same as this page.
Questions that come up
Are my photos uploaded?
No. The file is read with the browser's own decoder, the size is measured, and the bitmap is released again. There is no server-side step, and no image data is stored.
Why does a square photo fail a square spec?
Because the spec also fixes the pixel count. Shape and size are checked separately here so you can see which one is off: a 1000×1000 photo passes the aspect check on an 800×800 spec and fails the size check, which tells you to resize rather than crop.
Why is the background not judged?
Because "pure white" is a claim about pixels that needs a human look: an off-white studio backdrop, a soft shadow or a JPEG artefact can all turn a white background into a rejected one. Rather than guess, the page says it does not check it.
What if a spec changed after the data was collected?
Every spec in the library carries its source URL and the date it was last checked, and each marketplace page lists them. The marketplace's own seller centre always wins over this site.