Official pages only
Each marketplace guide is built from the marketplace's own pages: its help centre, seller centre, partner guidelines or official documents. The guide links to them and shows the day they were read. A rule that appears only on a third-party site is left out.
Nothing added
Each rule states only what the marketplace's page says, with nothing added. Where a page recommends rather than requires, the guide says recommended.
Figures counted, not typed
The figures on the statistics page, such as how many marketplaces ask for a pure white background, are counted from the same guide data each time the site is built. No figure is typed by hand.
One set of rules
The free product photo and image size checkers read the same rules as the guides and measure a photo in your browser; the photo is not uploaded. Tool comparisons use each company's own website, with the date it was read; a dash means the feature is not listed there.
Dates and corrections
The date on a guide changes only when its sources are read again. To report a rule that has changed, write to [email protected] with the marketplace and the page.
Checklist
- An official source is linked on every guide.
- Every guide shows the day its sources were read.
- Recommendations are marked as recommended.
- No figure is typed by hand.
Updated 30 September 2026