Blog · Guides

How to prepare your design file for shirt printing

2026-10-16 · 4 min read

If your design comes out blurry or with a white box around it, the file is usually the cause. Here's what to prepare before you upload.

Use PNG with a transparent background

PNG keeps sharp edges and supports transparency, so only your design prints, not a white rectangle around it. JPGs have no transparency and add blurry artifacts around edges.

Aim for 300 DPI at the printed size

DPI (dots per inch) is how many pixels land in each inch of the print. 300 DPI is ideal. Our design studio checks each image at the size you place it: Good at 200 DPI or more, OK from 150, and a warning below 150 that it may print blurry.

Pixels needed for common print sizes
Print size	At 300 DPI (ideal)	At 150 DPI (minimum)
Full front 30 × 40 cm	3543 × 4724 px	1772 × 2362 px
Center chest 25 cm wide	2953 px wide	1476 px wide
Left chest 9 cm wide	1063 px wide	531 px wide
Sleeve 10 × 9 cm	1181 × 1063 px	591 × 531 px

Avoid these

Screenshots and images saved from Facebook or Messenger, which are compressed and small
Enlarging a small image. It won't add detail, only blur
Very thin lines under about 1 mm, which can break up
Text close to the edge of the print area

Not sure? Ask for a free check

Message us before ordering and we'll check your file for free.

Frequently asked questions

What resolution do I need for shirt printing?

300 DPI at the printed size is ideal, and 150 DPI is the minimum. A full-front 30 × 40 cm print needs about 3543 × 4724 pixels at 300 DPI.

Can I use a JPG for shirt printing?

It's best to use a PNG with a transparent background. A JPG has no transparency, so its background prints as a box.

Start designing