How to Prepare a Print-Ready PDF: Bleed, Colour and Fonts

Commercial printing rejects files for a small, predictable set of reasons. If you have had a job come back with white slivers along one edge, colours that looked nothing like your screen, or a typeface you never chose, you have met three of them.

None of these are difficult to prevent. They are just invisible until they are expensive.

Bleed: why the white edge happens

Printing presses do not print to the edge of paper. They print onto a larger sheet and trim it down, and the trim is mechanically accurate to about a millimetre rather than perfectly.

If your background colour stops exactly at the page edge, a trim landing half a millimetre outside your artwork leaves a thin white line. On a business card with a dark background, this is immediately visible and ruins the whole run.

Bleed is the fix: extend any element that touches an edge beyond the trim line, typically by 3mm. The press trims through your artwork rather than to it, so any drift still lands on colour.

Three related measurements matter:

• Trim line — the finished size of the piece.
• Bleed — 3mm of artwork extending past the trim on every edge that has colour running off.
• Safe area — 3–5mm inside the trim, within which all text and important detail should sit. Trim drift works both ways, and text placed right against the edge can lose its outer millimetre.

So a document intended to finish at 85×55mm is built at 91×61mm with the design running to the outer edge, and nothing important within 4mm of the finished boundary.

If you supply artwork without bleed, the printer must either scale it up slightly — changing your dimensions — or accept the risk of white edges. Neither is what you wanted.

Colour: why it looks different on paper

Screens emit light and mix red, green and blue. Presses lay down ink and mix cyan, magenta, yellow and black. These produce genuinely different ranges of colour, and RGB's range is considerably wider.

The practical consequence is that the most vivid colours on your monitor — bright saturated oranges, electric blues, vivid greens — cannot be reproduced in CMYK ink. When the file is converted, they are mapped to the nearest printable equivalent, which typically looks duller. This is not a printing error; it is a physical limit.

What to do about it:

• Design in CMYK when the destination is print, so you see the achievable colours from the start rather than being disappointed at the end.
• If your brand colour is critical and sits outside CMYK range, ask about a spot colour (Pantone). It is a separately mixed ink, costs more, and reproduces exactly.
• Do not judge colour from your monitor. An uncalibrated screen is not a proof. If colour accuracy genuinely matters, request a physical proof before the full run.

One specific trap: black. Small text should be printed in pure black (K only — 0/0/0/100), not "rich black" mixing all four inks. Rich black on small type requires all four plates to align perfectly, and any misregistration produces coloured fringing that makes text look blurred. Use rich black for large solid areas, pure K for body text.

Fonts: embed them or lose them

If a font is not embedded in the PDF, the printer's system substitutes whatever it considers closest. Line breaks change, spacing changes, and your carefully set headline becomes something else.

Every serious PDF export path embeds fonts by default, but the setting can be turned off and some older workflows do not do it. Check rather than assume.

There is a licensing dimension too. Some fonts, particularly free ones, restrict embedding. If a font's licence forbids embedding, the export may silently exclude it. Converting text to outlines — turning letters into vector shapes — sidesteps both the embedding and the licensing question entirely.

The trade with outlining is that the text is no longer text: it cannot be searched, selected, or corrected without going back to the source. Outline as a final step on a copy, never on your working file.

Resolution: 300 DPI at final size

Print needs roughly 300 dots per inch at the size the image will actually appear.

The qualifier matters. An image that is 300 DPI at 5cm wide is 150 DPI when you scale it to 10cm, and it will look soft. What counts is the pixel dimensions relative to the printed size, not the DPI number stored in the file's metadata.

Images pulled from a website are typically 72–96 DPI and sized for screen. They almost always look poor in print. There is no software that meaningfully recovers detail that was never captured — upscaling invents pixels, it does not restore them.

Line art and logos should be vector wherever possible, which is resolution-independent and stays sharp at any size.

The checks to run before sending

Work through these on the exported PDF, not the source file. What you send is what gets printed.

1. Open the exported PDF and look at it. More errors are caught by actually viewing the export than by any other single step.
2. Confirm the page size is your finished size plus bleed, and that it is consistent across all pages.
3. Check artwork runs to the bleed edge wherever colour meets a trim line.
4. Check nothing important sits within 4mm of the trim.
5. Confirm fonts are embedded. In most viewers this is under document properties, in a fonts tab. Each font should be listed as embedded or embedded subset.
6. Check colour mode matches what the printer asked for.
7. Check image resolution at final placed size.
8. Flatten transparency if the printer requests it — some older RIP software handles live transparency unpredictably.
9. Ask what the printer wants. They will tell you their required bleed, colour profile and preferred PDF standard, and following that specification is faster than guessing well.

That last point does more work than the rest combined. Print shops answer this question every day and would far rather spend two minutes on email than reprint a job.

Common formats and what they need

Business cards — the least forgiving, because they are small and usually have a coloured background running off all four edges. Bleed is essential. Keep text well inside the safe area; a card with the phone number 1mm from the trim will lose digits on some of the run.

Flyers and posters — same principles, more room for error because the safe margin is proportionally smaller. Watch resolution on large formats, where images are scaled up considerably.

Multi-page documents — page size must be identical throughout. Mixed page sizes in one PDF is a common cause of rejection. Also confirm whether the printer wants single pages or reader's spreads; supplying the wrong one means the document assembles incorrectly.

If you are making a card from scratch, our free business card maker produces a layout with sensible margins that you can export and take to a printer. As with anything print-bound, confirm the required bleed and colour setup with your print shop before committing to a run.

The rule underneath all of it

Print is unforgiving because it is physical. A mistake in a web page is a deploy away from being fixed; a mistake in five hundred printed cards is five hundred printed cards.

Ten minutes of checking against a specification you obtained from the printer, before you send, is the cheapest insurance available in the whole process.