Print-Ready Files for Merch: Sizes, Formats and Color Tips

A design can look perfect on your screen and still come out wrong: a white box around it, blurry edges, a dark gray that vanishes on a black shirt. Most of these problems are decided before you ever upload, in how you set up and export the file.

This guide covers the specs Merch asks for, the sizes per product type, and the color habits that keep printed shirts looking like your mockup. Everything below was checked against Amazon's Merch resources pages in October 2026. Amazon updates them, so always confirm on the templates page before a big batch.

The core spec

On its templates page, Merch says artwork should be:

• PNG format with transparency
• sRGB color space
• Less than 25 MB
• The pixel size of the product's template (4500 by 5400 pixels for standard t-shirts)

Merch's Best Practices page adds: create the artwork in RGB, and output it "at 100% of the print dimensions at 300dpi".

What those terms mean:

• PNG is an image format that supports transparency. JPG does not, which is why a JPG would carry a solid background onto the shirt.
• Transparency means the empty parts of your canvas are see-through, so only your design prints.
• sRGB is the standard screen color space. Merch asks for RGB files, not CMYK, even though printers think in CMYK, and handles the conversion itself.
• 300 DPI (dots per inch) at the full print size is where the pixel numbers come from: 4500 pixels divided by 300 is 15 inches wide, and 5400 divided by 300 is 18 inches tall.

Pixel sizes per product

This is the list on Amazon's templates page as of October 2026. Products that share a size share a template.

Which products you can use depends on your account and marketplace, and the list changes. Your Merch create page is the final word.

Use the official templates

Amazon offers downloadable templates for Adobe Photoshop, Adobe Illustrator and GIMP, grouped by print size. Some include product mockups, others are "art size only".

Why bother:

• They show the printable area and, for several products, the safe zone. Anything outside the safe zone may still print but can be cut off by seams, cut lines or camera holes.
• Phone cases and zip hoodies have awkward areas (camera cutouts, the zipper). The template shows where not to put details.

If you work in Affinity or Photopea, both open PSD files, so you can start from the Photoshop template. Our post on design tools for Merch compares the apps.

The newer design editor

Merch's Best Practices page also describes a newer design editor that accepts artwork of any size larger than 485 by 485 pixels and scales it to each product. Amazon's advice for it:

• Start large: at least 4500 pixels on the long side, a bit more for flexibility. The editor can shrink art but not enlarge it.
• Trim extra transparent pixels so the file ends at the edges of your design. This lets the editor's centering tools work as expected.
• Save as PNG, RGB, 8 bits per channel, under 25 MB.

You can still upload full-template-size files. Just know that empty transparent space counts as part of the artwork when the editor centers it.

Size and placement on apparel

From Merch's Best Practices page:

• You don't have to fill 15 inches. Amazon says a design at 12 inches wide or less often centers better and feels less overwhelming.
• Place designs near the top of the print area. For apparel, that usually does best.
• Center visually, not just mathematically. A heavy element on one side can make a centered design look off.
• Print areas start below the collar: about 1.5 inches down on the front and 3 inches on the back, with exceptions such as the men's raglan.
• V-necks use the same art size but print lower, because the area starts below the tip of the V.
• Zip hoodies print across the zipper. Avoid fine lines and small text there.

And think about where your design lands on a body. The same file prints on men's, women's and kids' sizes.

Colors on dark and light shirts

Merch prints apparel with direct-to-garment (DTG) printing using water-based inks. Those inks are slightly see-through. On dark garments, a white base layer prints first and the colors go on top.

What that means for you:

• Low contrast disappears. Amazon's own example: a dark gray design on a black shirt may not print as expected. Same for pale yellow on white.
• Screen colors are brighter than print. RGB on a monitor looks more vivid than ink on fabric. Expect slightly duller results, especially neon-like colors.
• Use true black. Amazon says the richest black is R0 G0 B0 (#000000).
• Avoid colors that nearly match the shirt. They can vanish or print a hard-edged halo.
• Heather shirts (the speckled ones) mute fine detail and mid-tones.

Tip Decide the shirt colors before you design. If you want a design on black and white shirts, either make two versions or pick colors that contrast with both.

Soft edges and glows

Watch out Semi-transparent pixels (soft shadows, glows, feathered edges) are risky on dark shirts, because the white base layer under them can show as a muddy outline. If you use them, preview on a dark mockup and consider ordering a sample.

Text and line sizes

Merch's Best Practices page gives minimums, measured at full print size:

Thin script fonts are the usual victim. If a stroke is hairline-thin on screen, it will break up on fabric.

Export checklist

Before you upload, check:

1. Canvas is the right pixel size for the product (or large and trimmed, for the new editor).
2. Background is transparent: no white or colored layer hiding underneath.
3. Color mode is RGB, profile sRGB.
4. File is PNG and under 25 MB. In Photoshop, "Smallest File Size" in the PNG options helps, as Amazon suggests.
5. No stray pixels at the edges (zoom in on the corners).
6. Text and lines meet the minimum sizes.
7. Contrast works on every shirt color you will select.
8. Spelling is checked. Then check it again.

Some rejections trace back to file problems like these. Our post on why Merch designs get rejected covers the rest.

The short version

• Transparent PNG, sRGB, under 25 MB, at the template's pixel size (4500 x 5400 for standard tees).
• Work from Amazon's templates and respect the safe zone.
• Keep designs near the top and often 12 inches wide or less.
• Plan for contrast against every shirt color; avoid near-matching colors.
• Respect minimum text and line sizes, especially on hoodies.
• Specs change, so recheck Amazon's templates page before a big batch.

MerchPPC doesn't check or upload artwork. Once designs are selling, its Catalog shows them all in one table, so you can see which designs and product types earn and which have never sold. At the design level it also shows coverage: which product types and marketplaces each design is missing from.