What files should be prepared for printing?
Each book component requires a separate correctly prepared file. Depending on the project, these may include:
- cover files (softcover, hardcover, booklet binding, Wire-O),
- interior files (book block),
- dust jackets, endpapers and other additional elements,
- refinement files (UV varnish, foil, Book Edge Printing).
Each file should be prepared according to technical guidelines — both in terms of dimensions and file structure:
PDF format and basic requirements
Production files should be saved in PDF format, ensuring project consistency during printing. The most important rules are:
- use the PDF/X-4:2010 standard,
- work in the CMYK colour space,
- maintain correct resolution (300 DPI),
- embed all fonts or convert them to outlines.
This is the foundation that helps avoid file interpretation errors during production.
Bleed and margins — what should you remember?
Bleed and margins determine whether the project will look correct after trimming:
- bleed – standard 3 mm on each side,
- inner margins (safe areas) – protecting important design elements from trimming or disappearing into the spine.
Missing or incorrectly prepared bleed is one of the most common file preparation errors.
Preparing refinement files
Elements such as UV varnish or foil require separate files:
- masks should be prepared using 100% black (K),
- the file indicates the exact placement of the refinement,
- precise alignment with the base design must be maintained.
Files for die-cutting and special elements
More advanced projects (e.g. Die-Cut Window in the Cover) require additional technical files.
- the die-cut file defines the shape and position of the cut,
- it is prepared similarly to refinement masks,
- it must be precisely aligned with the design.
These solutions are mainly used in special and premium editions.
The most common file preparation mistakes
Most file problems result from several recurring issues:
- missing bleed or incorrect margins,
- using RGB instead of CMYK,
- insufficient resolution,
- project dimensions inconsistent with the actual format.
In most cases, these errors can be avoided by working from the beginning on a correct template.
What next?
If you want to ensure your files are prepared correctly, use the template generators available on our website. This is the fastest way to match your project to production parameters and avoid corrections at later stages.
