When you need this conversion
Print specifications arrive in millimeters: the trim size, the bleed, the safe margin. Photoshop, Figma, Canva and most export dialogs want pixels. Converting before you start means the artwork is sharp at the size it prints and you never have to scale up a finished design.
Worked approach for a print file
- Take the trimmed size from the printer’s spec, say 148 × 210 mm for an A5 flyer.
- Add bleed on every side, typically 3 mm: 154 × 216 mm.
- Convert at 300 DPI: 1818.9 × 2551.2, rounded up to 1819 × 2552 px.
- Create the document at that size and keep text at least 3–5 mm inside the trim.
Rounding
Images only have whole pixels. For print, round up rather than down so the artwork always covers the area. A single pixel is only 0.08 mm at 300 DPI but a missing pixel row can show as a hairline at the trim.
Common mistakes
Creating the file at 72 or 96 DPI. A 210 mm wide design at 96 DPI is only 794 px wide. Printed at 300 DPI it covers 67 mm, or it is enlarged and looks soft.
Forgetting bleed. Backgrounds that stop exactly at the trim often show a thin white edge after cutting. Always add the bleed before converting.
Need the reverse? Use the pixels to millimeters converter. For whole sheets, the paper size calculator lists every standard size in pixels.