Notes
Merch by Amazon dropped the 4500 × 5400 rule
If you have been resizing every design to exactly 4500 × 5400 because one pixel off meant rejection, you can stop. That rule is gone, and Amazon says so in its own documentation.
What the documentation actually says now
The Best Practices page in the Merch on Demand resources section, under New Design Editor, states it plainly: product templates previously required specific artwork for each product type, but you are no longer required to export or upload specific sizes. The editor accepts artwork of any dimension greater than 485 × 485 pixels and scales it to fit and centre on each product. The templates still exist and are still useful for previewing placement — they are simply no longer a gate.
What replaced it
Three numbers, and only one of them is a rule. 485 × 485 is the hard floor; below it the upload is refused. 25 MB is the file ceiling, written down twice on the same page, and it is the constraint you will actually hit. Everything else is advice: start at 4500 pixels or more on the long edge so the editor has room to scale down, export RGB at 8 bits per channel, and trim the transparent margin. That last one matters more than it sounds.
Then and now
| Dimensions | was exactly 4500 × 5400 — now anything above 485 × 485 |
|---|---|
| Undersized file | was refused — now accepted and scaled |
| Oversized file | was refused — now scaled down to fit |
| File size | 25 MB, unchanged and still written down |
| Colour | RGB required; Amazon converts to CMYK for printing |
| Padding | was necessary — now actively unhelpful |
Why padding went from required to harmful
Under the old rule, the way to hit 4500 × 5400 exactly was to centre your artwork on a transparent canvas of that size. Under the new editor that padding works against you. Amazon asks you to trim the file to the edges of your design, because the centring tools measure the bounds of the artwork itself — a transparent margin is measured as part of the design, so the automatic placement lands somewhere you did not intend. The margin also costs bytes against the 25 MB ceiling while contributing nothing.
Batch, auto-fix and exports
Everything above is free for one file at a time, and always will be. Doing it to a whole folder — batch checking up to 100 files, one zip with every platform file for every design, and a CSV report — is part of Seller.
Exports are padded and centred to each platform's size on a transparent canvas. Nothing is ever upscaled — a file enlarged to pass a dimension check still prints soft, which is the failure this tool exists to prevent.
Why so many guides are still wrong
The exact-size requirement held for years, and it generated an enormous amount of content — templates, tutorials, YouTube walkthroughs, forum answers, and a generation of tools built to check for one specific pixel count. None of that updates itself when a platform relaxes a rule quietly. The practical consequence is that a checker built on the old spec will tell you a perfectly acceptable file is going to be rejected, which is a worse failure than missing a real problem: it sends you off to fix something that was never broken.
Frequently asked questions
Should I stop using 4500 × 5400 then?
No. It is still the sensible size to work at — it is 15 × 18 inches at 300 DPI, it matches the largest apparel print area, and it gives the editor room to scale down for every product. The change is that it is now a good default rather than a pass/fail gate, so a 4000 × 4800 design no longer needs rebuilding.
Do the downloadable templates still matter?
They are useful for seeing where the print area and safe zones fall on a specific product, which is a placement question rather than a file-format one. You no longer have to export at the template dimensions.
What happens if my file is 30 MB?
That one is still a hard stop, and it is the limit most designs actually run into. Trim the transparent margin first since it costs nothing, then reduce colour depth, and only scale the canvas down as a last resort.