How can you tell if a PDF is ready to print?
A PDF is print-ready when it meets your printer's own specification, because there is no single standard. Printer specifications commonly cover the same six things: page size, bleed, fonts, image resolution, colour mode and file protection. Check each against what your printer asks for, then check the exported file itself, not the design it came from.
Key points
- Print-ready is defined by your printer. The same file can be fine for one and rejected by another.
- Specifications commonly cover six things: page size, bleed, fonts, image resolution, colour and protection or extras in the file.
- Check the exported PDF. A setting in your layout program is not proof that the PDF contains it.
- Some things cannot be checked from the file: overprint, ink coverage and safe margins need your printer's own tools.
- Fixing one problem can leave another in place, so check again after every export.
The six checks
The figures below come from published specifications where one exists and are marked as our working values where it does not.
| Check | What printers commonly ask | Where it comes from |
|---|---|---|
| Page size | The finished size, with the right page boxes set | Your printer's template |
| Bleed | Artwork extending past the trim edge, typically 0.125 in (3 mm) | Adobe calls this typical and says to verify with your print provider. KDP asks for 0.125 in (3.2 mm) on the top, bottom and outside edges of a paperback interior. |
| Fonts | Every font embedded | KDP: all fonts in the interior and the cover embedded |
| Image resolution | About 300 pixels per inch at the printed size | KDP: images at least 300 DPI, with 600 recommended as a maximum. The 300 target and 150 floor for general print are our working values. |
| Colour | CMYK or RGB, as your printer says | Adobe: CMYK for images printed with process colours; the printer decides |
| File protection and extras | No locked or encrypted file, and no leftover comments or crop marks | KDP lists locked or encrypted files as a common failure and says files should not contain crop marks, comments, annotations or placeholder text |
For the detail behind each row, see the guides on bleed, resolution, fonts and colour.
What we tested
We made two small test PDFs of an A4 flyer and ran each through the Print-Ready PDF Checker with the General print profile. We told it the finished size is A4, that the design reaches the edge, and that the printer asks for CMYK only.
First export. The page is exactly A4 with no bleed, one photo of 1000 × 700 pixels is placed across the full 210 mm width, the text uses Helvetica, and the colours are RGB.
Second export. The page is A4 plus 3 mm bleed on every side, the photo is 2600 × 1850 pixels placed 216 mm wide, the text uses an embedded font, and the vector colours are CMYK.
| Check | First export | Second export |
|---|---|---|
| Page size | Passed: 210.0 × 297.0 mm | Passed: 210.0 × 297.0 mm |
| Bleed | Fix: 0.0 mm, 3.0 mm required on every trimmed edge | Passed: 3.0 mm |
| Fonts | Fix: Helvetica not embedded | Passed: 1 of 1 embedded |
| Image resolution | Fix: 121 PPI at its printed size, 150 PPI minimum | Passed: 306 PPI |
| Colour | Fix: RGB found, the printer asks for CMYK | Fix: RGB found in 1 image |
Four problems became one. The second export still fails the colour check, and the report says why: one image is RGB, even though the vector colours are now CMYK. In our file this happened because the generated photo is an RGB JPEG, which we did not change. It shows the common case where a fix is applied to the page but not to the placed photo, and the file keeps more than one source of colour.
The first export's image number is also a good example of why the printed size matters. The photo has 1000 pixels across 210 mm, which is 121 pixels per inch. The same photo placed at half the width would be about 242.
We also ran a third test PDF with the Book interior profile, which follows KDP's published values, after adding security settings that still let the file open without a password. The checker reported that the PDF is encrypted, marked it Fix, and noted that it opens without a password. KDP names locked or encrypted files as a common failure, which is why the Book interior profile treats it as a failure while the General profile marks it for review.
What it cannot check
The checker marks a set of things as not inspected, so that nothing is passed silently: overprint, total ink coverage, safe margins, hairline thickness, minimum font size, printer's marks and hidden objects, and transparency is only partly inspected. Safe margins matter in particular, because bleed covers the edge and a margin keeps text away from it. Ask your printer how they check those.
A Passed result means no problems were found in the checks listed. It does not mean your printer will accept the file, and our two test files are generated documents with simple page content.
A routine that works
- Ask your printer for their file specification or template before you design.
- Set the finished size and the bleed in your layout program, and export to PDF.
- Run the exported file through a checker, and open it yourself as well.
- Fix the problems at the source and export again. Do not patch the PDF if you can avoid it.
- Check the new file, because a fix in one place can leave another problem or introduce a new one.
What to do next
Start with your printer's specification, then check the file you will send. For how the checks work and what they leave out, read how Check Before Submit works.
Sources
- Amazon KDP Help: Paperback submission guidelines (read on 3 October 2026)
- Amazon KDP Help: Set trim size, bleed, and margins (read on 3 October 2026)
- Adobe InDesign Help: Print bleed and slug areas (page last updated 2 June 2026) (read on 3 October 2026)
- Adobe Photoshop Help: Understanding color modes (page last updated 15 November 2022) (read on 13 October 2026)
Figures taken from these sources are quoted as written on the date shown. Your printer's own specification always comes first.
More guides
What does a KDP paperback interior PDF need?
Trim size, bleed on three edges, margins by page count, 300 DPI images and embedded fonts. KDP's published numbers, and what a check can and cannot verify.
What are Adobe Stock's technical requirements for photos?
JPEG, sRGB, 4 to 100 megapixels, 45 MB at most. Adobe's published photo requirements in one table, which of them a file check can verify, and what happens at the edges.
Why does Adobe Stock refuse photos for quality?
Adobe asks for a sharp main subject, minimal noise and artifacts, and balanced light. What each means, and what software could and could not catch on 96 real photos.