Print-on-Demand Design: From Artwork to Product File

A print-on-demand design is artwork prepared for one product, print area, provider, and printing method. There is no single PNG size that is correct for every shirt, mug, poster, or phone case.

Printify says its recommended image size can change by product, print area, and sometimes garment size. Its current advice is to open the Upload section for the exact product in Product Creator and use the requirements shown there. Read the Printify dimension guide before you set up the file.

MerchBanao gives you a browser workflow for creating and editing an artwork draft. You can start with a prompt or upload an image, remove a background, move text and image layers, choose from 50 fonts, and preview the composition on white and black shirts.

The current download is a fixed 4200 × 4800 PNG with the editor background hidden. That is enough pixels for a 14 × 16 inch print area at 300 pixels per inch, but it is not an automatic Printify, Printful, Amazon, Redbubble, mug, embroidery, or all-over-print preset. Compare the downloaded file with the live product template before you publish it.

Use this calculation: required pixels = intended print size in inches × the provider's requested pixels per inch. A 4200-pixel image printed 14 inches wide has 300 pixels per inch. Stretch the same image to 28 inches and it drops to 150. Changing only the DPI metadata does not create new detail.

Printful currently asks for files that are at least 150 DPI and sized for the actual print dimensions. Its resolution guide also points sellers to the file guidelines for each catalog product. Use that live product guidance as the authority.

A centered shirt graphic can often be adapted to another garment, but it should not be uploaded blindly to every product. Redbubble's current guide lists 2400 × 3200 pixels for its “Other Apparel” print area, 2700 × 1120 for a standard mug, and 2800 × 2800 for its largest sticker size. It also recommends portrait, landscape, and square variations.

Check the full Redbubble dimensions and format table, then inspect the preview for every enabled item. For Amazon Merch on Demand, download the current product template from the official product templates resource instead of relying on a remembered canvas size.

First, define the buyer, product, garment colours, and the idea the design must communicate. Next, collect the provider's live template. Create the artwork in MerchBanao, then refine the text, hierarchy, spacing, and transparent edges.

After export, place the 4200 × 4800 PNG into the provider's product creator without stretching it beyond the required resolution. Preview every colour and print area, check that you have the rights to every phrase and visual element, and order a physical sample. A mockup catches layout problems; a sample catches print, fabric, colour, and placement problems.

Zoom in on the final PNG, not only the editor preview. Look for pale halos around removed backgrounds, clipped letters, tiny isolated pixels, unintended semi-transparency, and text that becomes unreadable at the intended print size. Check the design on the lightest and darkest product colours you plan to sell.

Keep the original prompt, source files, licenses, and research notes. Run a trademark and copyright review before selling. For a more detailed handoff, use the print-ready T-shirt checklist and the copyright and trademark guide.