The Complete PDF Preflight Checklist for Print

Nothing hurts more than a beautiful design that comes back from the printer with white slivers on the edge, muddy colors or blurry photos. Almost every one of those problems is preventable with a five-minute preflight. This checklist walks through exactly what prepress operators look for, in the order they look for it.

1. Confirm the trim size

The trim size is the final size of the piece after it is cut. Before anything else, make sure your document is set up at the size your printer quoted. A "letter" flyer is 8.5 × 11 in, a US business card is 3.5 × 2 in, a standard postcard is 6 × 4 in.

• Check the page size in your layout app, not just the artboard name.
• If your PDF has a TrimBox, it should match the finished size exactly.
• Multi-page documents should have every page at the same trim size (unless covers are intentionally different).

2. Add bleed on every side

Printers cut stacks of sheets at once, and the blade can drift by a fraction of a millimetre. Bleed is extra artwork past the trim line that absorbs that drift. The North American standard is 0.125 in (1/8", about 3 mm) on all four sides.

• A letter flyer with bleed exports as 8.75 × 11.25 in.
• Backgrounds, photos and color blocks that touch the edge must extend to the bleed line.
• Export with "Use document bleed settings" turned on — many PDF presets default to zero bleed.

3. Keep important content inside the safe zone

The same blade drift that requires bleed can also trim into your content. Keep text, logos and anything important at least 0.125 in inside the trim line (0.25 in is safer for small pieces like business cards).

4. Convert to CMYK

Presses print with cyan, magenta, yellow and black ink. RGB colors — the default for screens, stock photos and most web assets — get converted by the printer's RIP, often with dull or shifted results. Convert images and vector colors to CMYK yourself so you can see and approve the final look.

• Look for RGB images, RGB vector fills and RGB gradients.
• Choose a CMYK profile that matches your paper: coated, uncoated or newsprint.
• Respect the total ink limit (around 300% for coated stock, less for uncoated).

5. Check image resolution (effective DPI)

Every photo should be 300 DPI at its final placed size. What matters is effective resolution: a 300 DPI photo scaled to 200% in your layout is really 150 DPI.

Effective DPI	Result
300+	Sharp — pass
150–299	Acceptable for many jobs — warning
Under 150	Visibly soft or pixelated — fail

6. Handle fonts and rich black

• Embed all fonts or convert display type to outlines.
• Set small body text in 100% K (black only) so it stays crisp.
• Use a rich black such as C60 M40 Y40 K100 for large black areas.

7. Export a print PDF

Use a print preset such as PDF/X-1a or PDF/X-4, include bleed, and add crop marks only if your printer asks for them. Then open the exported file and preflight that — not your working document.

Automate the checklist

Artwork Proofing runs steps 1, 2, 4 and 5 automatically. Upload your PDF, enter the finished size, and you'll see the trim line, required bleed and crop marks drawn over your page, plus numbered callouts on every low-resolution image. Pro users can convert RGB to CMYK and rescue weak photos with AI upscaling in the same place.