Sending a PDF to print without checking it first is one of the most common — and costly — mistakes in print production. A file that looks perfect on screen can produce wrong colours, blurry images or white edges when printed.
This guide walks you through the 5 essential checks every PDF needs before going to print.
1. Check the Colour Mode
The most common print error is submitting an RGB file instead of CMYK.
- RGB is designed for screens — it cannot be reproduced accurately by printing presses
- CMYK is the standard for print — it uses four ink colours (Cyan, Magenta, Yellow, Key/Black)
If you send an RGB file to print, colours will shift — often becoming duller or darker than expected. Always convert to CMYK before exporting your PDF.
2. Check Image Resolution (DPI)
Images need to be at least 300 DPI (dots per inch) for high-quality print output.
- 72 DPI — suitable for web, but will appear blurry in print
- 150 DPI — acceptable for large-format printing (posters, banners)
- 300 DPI — standard for print (flyers, brochures, business cards)
Important: scaling up a low-resolution image does not improve quality. Always start with a high-resolution source file.
3. Check Bleed
Bleed is the area that extends beyond the final trim size of a printed document. It is needed because cutting machines are not perfectly precise — without bleed, you may see white edges on the final print.
The standard bleed is 3 mm on all sides. For example, an A4 document (210 × 297 mm) should be set up as 216 × 303 mm including bleed.
Make sure your background and design elements extend into the bleed area.
4. Check Fonts
If fonts are not embedded in your PDF, the printer's system may substitute a different font — changing the layout or making text unreadable.
To check fonts in Adobe Acrobat: File → Properties → Fonts tab. All fonts should show "Embedded" or "Embedded Subset".
Most professional design tools (InDesign, Illustrator) embed fonts automatically when exporting to PDF. PDFs created from Microsoft Word may miss fonts.
5. Check Page Size
Make sure your document size matches the intended print format exactly. A small mismatch can cause the printer to scale or crop your design.
If your file includes bleed, the document size should include the bleed area (e.g. 216 × 303 mm for A4 + 3 mm bleed).
The Fastest Way to Check Your PDF
Checking all five parameters manually takes time and requires experience. An automated tool can do it in seconds.
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Submitting an unchecked file can lead to:
- File rejection by the print shop
- Expensive reprints
- Delayed delivery
- Wrong colours or poor image quality in the final product
A quick preflight check takes less than a minute and can save significant time and money.