How to Prepare a PDF for Printing

A PDF that looks perfect on screen can still fail at the print shop. Commercial printing has stricter requirements than screen viewing: the color must be CMYK, images must be at least 300 DPI, fonts must be embedded, and the page must have bleed if the design runs to the edge. This guide walks through the pre-flight checklist for print-ready PDFs and shows which steps you can do locally with IXPDF — and which require going back to the source application.

The print pre-flight checklist

Every commercial print job has the same six checks. Walk through them in order before sending the file:

1. Page size and bleed — matches the print spec, with bleed if the design runs to the edge.
2. Color space — CMYK (or a named spot color), not RGB.
3. Image resolution — at least 300 DPI at final print size.
4. Fonts — all fonts embedded, none substituted.
5. Orientation — every page in the correct orientation for the print run.
6. Metadata — a clear title and author so the print shop can identify the job.

Step-by-step: pre-flighting a PDF for print

1. Check page size and bleed

Open the PDF and check the page size. For a business card, that is 85 × 55 mm (or 90 × 54 mm with 3 mm bleed). For an A4 flyer, that is 210 × 297 mm (or 216 × 303 mm with 3 mm bleed). If the page size is wrong, you must re-export from the source — page size is a property of the page geometry, not something to fix on a finished PDF without risking content shift.

Bleed is extra artwork that extends past the trim edge, so that when the paper is guillotined the color runs to the edge with no white border. Typical bleed is 3 mm (US: 0.125 inch). If your design has a background color or image touching the edge, you need bleed. If the design has a white margin around everything, you do not.

2. Verify color space (CMYK, not RGB)

Commercial presses print in CMYK (cyan, magenta, yellow, black). Screens display in RGB (red, green, blue). A PDF with RGB images will be converted to CMYK at the print shop, often with unexpected color shifts — bright blues and greens in particular can look duller in CMYK. The right fix is to convert to CMYK in the source application (InDesign, Illustrator, Photoshop) where you can preview the conversion and adjust. Converting a finished PDF to CMYK is possible but not recommended — you cannot preview the result reliably.

If you must check the color space of an existing PDF, open it in Adobe Acrobat Pro and use Output Preview (Tools → Print Production → Output Preview). Free alternatives include pdfinfo from Poppler and ghostscript.

3. Check image resolution (300 DPI)

Images should be at least 300 DPI at the final print size. An image that is 300 DPI at 100% scale but is scaled up to 200% in the layout is effectively 150 DPI and will look soft. The check is: open the PDF in Acrobat Pro's Output Preview and look at theObject Inspector, which reports each image's effective resolution. Anything below 300 DPI at final size should be re-exported from the source with a higher-resolution original.

Note that vector graphics (logos, line art, type) are resolution-independent — they print sharp at any size. The 300 DPI rule applies only to raster images (photos, scans, anything with pixels).

4. Embed all fonts

Every font used in the PDF must be embedded, or the print shop's RIP will substitute a different font and the layout will shift. To check, open the PDF in Acrobat Pro and use Fonts (File → Properties → Fonts). Every font should say "Embedded" or "Embedded Subset". If any say "Not embedded", re-export from the source with font embedding turned on (InDesign: Include All Fonts; Word: Embed fonts in the file in Save options).

Free alternative: pdffonts from Poppler lists every font and whether it is embedded. On macOS, mdls on the file shows some font info but is less complete.

5. Rotate to correct orientation

If any pages are sideways or upside down relative to the print orientation, use/tools/rotate-pdf/ to rotate them. This is the one print-prep step IXPDF does well — rotation is a structural operation that does not re-encode content, so it is fast and lossless. Rotate by 90, 180, or 270 degrees clockwise, optionally limited to a page range.

6. Set metadata for the print job

Use /tools/edit-metadata/ to set a clear Title (e.g. "Business Cards — Alice Chen — 500 copies") and Author (your name or company). The print shop uses this to identify your job in their queue. Good metadata prevents the "which file was this?" problem when you have multiple jobs in flight.

Send the right format: PDF/X

For commercial printing, the gold standard is PDF/X-4(based on PDF 1.6) or the older PDF/X-1a (based on PDF 1.3). PDF/X requires all fonts embedded, color in a print color space, and bleed and trim boxes defined. Most print shops accept PDF/X-4 today; some older workflows still require PDF/X-1a. Ask your print shop which they prefer.

You cannot convert a general PDF to PDF/X reliably on a finished file — the conversion needs to happen in the source application, which has the original artwork and color profiles. InDesign, Illustrator, and Acrobat Pro all have PDF/X export presets.

Common mistakes

• Sending an RGB PDF. The print shop will convert it, but the colors will shift. Convert to CMYK in the source application and preview the conversion before exporting.
• Forgetting bleed. If the design runs to the edge and there is no bleed, the guillotine will leave a thin white border on at least one edge. Add 3 mm bleed in the source application.
• Using 72 DPI images. That is screen resolution, not print resolution. Photos from web pages are usually 72 DPI and will look soft or pixelated in print. Use 300 DPI originals.
• Not embedding fonts. The print shop's RIP will substitute a different font and the layout will shift. Always embed.
• Using IXPDF to convert color or resolution. IXPDF does not re-encode images or convert color spaces — those changes need the source application. Use IXPDF for rotate and metadata, which are structural operations it does well.