Print-Ready PDF Checklist: Bleed, Resolution, Colour and PDF/X

A print-ready PDF is a file the printer can send straight to production without fixing anything: correct size, bleed, colour mode, resolution and embedded fonts, ideally saved as PDF/X. Most delays in print jobs start with files that look fine on screen but fail the printer's preflight check. Use this checklist before you send artwork, and always compare it with the supplier's own specification, because requirements differ between printers and products.

Why does a print-ready PDF matter?

Every file problem costs time, and time is usually the scarcest part of a print job. The printer has to spot it, contact you, wait for a new file and check again, and on a tight deadline that can push the job to another press slot. A print-ready PDF also protects you: if the printer has to convert colours or fix bleed for you, the result may not look the way you intended.

Responsibility matters as well, so read the printer's terms on who pays when an error in a supplied file or an approved proof leads to a reprint. Sending a print-ready PDF and checking the proof carefully is the cheapest insurance a buyer has. For agencies sending files on behalf of a client, the same applies: agree who approves the final proof before the job starts.

The print-ready PDF checklist

1. Size and bleed

• Set the document to the final trim size, for example A4 at 210 x 297 mm.
• Extend backgrounds and images that touch the edge beyond the trim line. A German packaging printer asks for 3 mm of bleed per side, while a UK printer asks for 2 mm on each edge, so check the figure with your supplier.
• Keep text and logos inside a safety margin. The same UK printer recommends 3 mm for most products and much more for banners.

2. Image resolution

• Use images of at least 300 dpi at final printed size for sheet-fed work, as both printers above recommend.
• Large-format items viewed from a distance can often use less; the UK printer accepts 150 dpi for posters and banners.
• Do not upscale low-resolution images in software and expect sharper print.

3. Colour

• Convert to CMYK using the profile the printer specifies, or leave RGB images in a colour-managed PDF/X-4 only if the printer agrees. One printer recommends the ISO Coated v2 300% (ECI) profile; for premium coated offset, the newer PSO Coated v3 profile is based on ISO 12647-2:2013 (ICC profile registry).
• Name spot colours exactly as agreed, for example a Pantone reference, and remove unused spot colours (see CMYK vs Pantone).
• Check that small black text is set in black only, not a four-colour mix, so it stays sharp.

4. Fonts and lines

• Embed all fonts or convert them to outlines.
• Avoid very thin lines: one printer, for example, sets a minimum of 0.25 pt, and 0.5 pt for reversed-out elements.

5. File format

• Export as PDF/X if the printer accepts it, and use the version they ask for.
• Supply single pages in reading order, unless the printer asks for spreads.
• For packaging, ask how the supplier wants the cutting and creasing line marked, and keep it on its own layer or spot colour.

PDF/X-1a or PDF/X-4 for a print-ready PDF?

PDF/X is a family of ISO standards for exchanging print files. ISO 15930-7 defines PDF/X-4, which is based on PDF 1.6 and allows colour-managed data, CMYK, greyscale, RGB and spot colours, live transparency and optional content (layers). ISO lists it as reviewed and confirmed in 2026.

PDF/X-1a is older and stricter: everything must already be converted to CMYK and spot colours, and transparency must be flattened. As the PDF Association explains, the real difference is where responsibility sits. With PDF/X-1a, the designer resolves colour and transparency; with PDF/X-4, the printer's RIP does more of that work. The Ghent Workgroup, which publishes free industry specifications, bases its current commercial print specification on PDF/X-4 (GWG, commercial print).

What PDF/X does not check

A valid PDF/X file is not automatically a good file. As the FLYERALARM blog points out, PDF/X checks things like embedded fonts and colour spaces but not image resolution. Bleed, safety margins and content errors also remain your responsibility.

Common print-ready PDF mistakes

• Bleed added to the page size. The document becomes 216 x 303 mm instead of A4 with bleed around it, and the printer's imposition no longer fits.
• Images copied from websites. They look sharp on screen but are far below print resolution.
• Brand colours in RGB. They shift when the printer converts them, often towards duller tones.
• Missing or substituted fonts. Text reflows or changes appearance on the printer's system.
• Several versions with similar names. Label final files clearly, for example with date and version, so nobody prints an old draft.

Print-ready PDF files for large format and packaging

Banners, roll-ups and signage

Some large-format suppliers want files at a reduced scale, such as 1:10, with resolution set for that scale, plus extra bleed or hem allowance for finishing like eyelets or pockets. Ask before you start the design, because rescaling a finished layout can cause problems with fine lines and text.

Cartons and labels

For packaging, the supplier usually provides the cutting template. Place your artwork on that template, keep the die line on its own layer, and do not move or resize it. Glue areas and fold lines may need to stay free of ink or varnish. A print-ready PDF for a carton therefore depends on the supplier's technical drawing more than on general rules.

Final checks before you send the print-ready PDF

1. Open the PDF in Acrobat or a similar tool and view the output preview or separations.
2. Check page count, page order and the trim box on every page.
3. Zoom in on images at 100% to spot pixelation.
4. Read the text one more time, because no preflight tool catches a wrong phone number or a typo in a price.
5. Ask for a digital or hard-copy proof for important jobs, and approve it in writing.

Help with artwork through Flobid

If you do not have a designer, you can send a request to graphic design studios on Flobid to prepare print-ready files. The printing buyer resource pack also includes a file checklist you can share with your team. Paper choice affects colour too, as explained in our paper weight guide.

Sources

1. ISO 15930-7:2010 Graphic technology, Prepress digital data exchange using PDF, Part 7: Complete exchange of printing data (PDF/X-4) and partial exchange of printing data with external profile reference (PDF/X-4p) using PDF 1.6, ISO (2010)
2. Which PDF/X should I use?, PDF Association (2020)
3. Everything you need to know about commercial print, Ghent Workgroup
4. Data check, ideas in boxes
5. How to check your artwork for print, Aura Print (2024)
6. The PDF/X print format, FLYERALARM (2021)
7. PSOcoated_v3.icc, International Color Consortium