DTF File Prep: PNG, PDF, 300 DPI and CMYK Explained

Most DTF problems are not press problems — they are file problems, and they are visible before anything is printed. Here is what makes a file print well.

Use PNG with a transparent background

PNG is our preferred format. It supports transparency, which is what tells the printer where not to lay down white ink. If your artwork has a white box behind it, that box will print as solid white ink and appear as a visible rectangle on the garment.

PDF is also accepted and is a good choice for ready-to-print layouts. We support AI, PSD and EPS as well.

Before uploading a PDF

• Convert all fonts and strokes to outlines or shapes
• Embed every image — nothing linked to an external file

A PDF that references a font you have installed and we do not will substitute that font, and the result will not be what you designed.

300 DPI at final print size

Resolution only means something at a stated size. A 1000 × 1000 pixel file is 300 DPI at roughly 3.3 inches — and about 83 DPI if you stretch it to 12 inches, which will print visibly soft and pixelated.

The rule: set your canvas to the actual size you want printed, at 300 DPI, then design at that size. A 12" × 12" print at 300 DPI is 3600 × 3600 pixels.

Never upscale a small file

Enlarging a low-resolution image does not add detail — it adds blur. A logo pulled from a website at 400 pixels wide cannot become a clean 11-inch back print. Ask for the original vector file, or rebuild it.

Colour: design in CMYK if colour matching matters

Screens display RGB; printers lay down CMYK. Bright RGB colours — especially electric blues, neon greens and hot pinks — sit outside what CMYK ink can reproduce, so they shift when converted. If exact colour matching matters for a brand, design in CMYK from the start so you are seeing something close to the printed result.

Thin lines and small text

DTF holds fine detail well, but there is a floor. Keep strokes at 1.5 pt or heavier and text at 8 pt or larger. Thin outlines and delicate scripts can break up on the film or lift during peeling.

Quick checklist

• PNG with transparent background (or a properly prepared PDF)
• 300 DPI at the actual print size
• No white box behind the design
• Fonts outlined, images embedded
• CMYK if brand colours must match
• Strokes 1.5 pt+, text 8 pt+

Where to upload

Send a finished layout through Upload Gang Sheets, or arrange individual designs yourself in the Gang Sheet Builder. If you want us to handle the layout, order by size instead.

Next: learn how gang sheets cut your cost, then how to press your transfers.