How to fix color and ink problems

Screens make color with light (RGB). Printers use four inks (CMYK). Most color errors come from a file that's still in screen color, or from black made out of all four inks at once.

Quick answer

Convert color files to CMYK and keep total ink (C+M+Y+K) under 240% for IngramSpark. Make black text 100% K only. For a black and white book, export the interior as grayscale so no color or rich black is left.

Want the answer for your book? Upload it and SparkPrep checks it against your printer's own rules.Scan my book free

Three different problems

Problem	Who rejects it	Usual cause
RGB color in the file	IngramSpark (PDF/X-1a), Lulu; KDP converts it but colors can shift	Files from Word, Canva or phone photos
Total ink over 240%	IngramSpark	Rich black backgrounds, dark photos converted without an ink limit
Color in a black and white interior	All printers	"Black" text saved as RGB, blue links, a colored logo

Black and white interior: the fastest fix

Export it as grayscale. Grayscale uses black ink only, so it can never go over 100% ink and has no color in it.

Acrobat Pro: Tools → Print Production → Convert Colors.
Conversion profile: a gray profile such as Dot Gain 15% or Gray Gamma 2.2. Apply to all pages.
Save as a new PDF and upload that one.

No Acrobat? In Word, set all text to Automatic/black, turn pictures to grayscale (Picture Format → Color → Grayscale) and remove blue hyperlinks (select all, Ctrl+Shift+F9 turns links into plain text). It reduces the problem, but Word can't make a true grayscale PDF.

Color covers and interiors: bring ink under 240%

Find it: Acrobat Pro → Print Production → Output Preview → tick Total Area Coverage, set 240%. Problem areas light up.
Black text and black shapes: make them C0 M0 Y0 K100, not a "rich" mix.
Big black backgrounds: use a lighter rich black, for example C40 M30 Y30 K100 (200% total).
Photos: convert to CMYK with a profile that has a low ink limit, then check Output Preview again.
Export as PDF/X-1a.

Canva

Canva Pro's PDF Print download has a CMYK color profile option. Use it for covers. It doesn't let you set an ink limit, so dark Canva covers often still pass KDP but fail IngramSpark's 240% check. Check the downloaded file, or let SparkPrep measure it.

Expect colors to change a little

Bright screen colors (electric blue, neon green, hot pink) can't be made with ink. They print duller. Look at your cover in CMYK before you approve it, and order a proof.

SparkPrep measures the ink on every page, brings it under 240% while keeping black text sharp, and exports true black and white interiors.

Want every click spelled out? Read the full walkthrough: "Ink coverage exceeds 240%" on sparkprep.legenddary.com.

Want every click spelled out? Read the full walkthrough: RGB found in a black and white interior on sparkprep.legenddary.com.

Find out what's wrong with your files before the printer does

SparkPrep checks your cover and every interior page against the exact rules Amazon KDP, IngramSpark, Barnes & Noble Press and Lulu use, tells you each problem in plain English, and can fix it for you.

Scan my book free See how SparkPrep works

The scan is free and shows how many problems your files have. To see every problem and where it is, the audit is $1.99 ($3.99 after January 1). The Advanced Audit checks every page, up to 300, for $9.99.

Questions people ask

What is total ink coverage?

Cyan, magenta, yellow and black added together at one spot. 100% black alone is 100%. A rich black can be 300% or more.

Does KDP need CMYK?

KDP accepts RGB and converts it, but colors can shift. IngramSpark's PDF/X-1a requires CMYK or grayscale.

More on this site

Fix your book's print filesPlain-English fixes for the book file problems printers reject: bleed, margins, fonts, transparency, low-resolution pictures, color, ink, page size and spine.How to add bleedHow to add 0.125 inch bleed to a book cover or interior in Canva, InDesign, Affinity or Word, how to check it, and why bleed errors come back.How to fix book marginsFix interior margin errors: KDP's inside gutter by page count, IngramSpark's 0.5 inch safety area, and margin settings in Word, InDesign and Affinity.Fix PDF page sizeIf your interior PDF is letter size but your book is 6x9, the printer shrinks or crops it. How to set the right trim size in Word and InDesign.How to embed fontsFix 'font not embedded' and font license errors in your book PDF: how to embed every font in Word, InDesign, Affinity and Canva, and how to check in Acrobat.How to flatten transparencyShadows and see-through shapes can print as boxes. How to flatten transparency and layers for KDP and IngramSpark in Canva, InDesign, Affinity and Acrobat.Fix low-resolution picturesHow to fix low-resolution (under 300 DPI) pictures in a book: pixel sizes for common covers and pages, how to stop Word compressing images, and what not to do.Fix spine width and spine textFix a wrong spine width or spine text error: how to re-fit your cover for a new page count or paper, center spine text and know when spine text is allowed.

Free help from SparkPrep

Book Preflight, ExplainedWhat book preflight is, who needs it and what gets checked before KDP or IngramSpark prints your book.Print Cover SizesFull cover size charts, spine widths, barcode space and hardcover rules for KDP and IngramSpark.Rejection Messages DecodedWhat KDP and IngramSpark rejection messages really mean, in plain English, and what to do next.First Book GuideYour first print book, step by step: costs, timeline, words to know and the mistakes to skip.Free book toolsCover calculator, spine width, margins, DPI checker and page count, on sparkprep.legenddary.com.

Last updated 2026-11-01. Written by Joshua Davis, founder of SparkPrep. Numbers come from each printer's own published guides; always double-check your printer's current rules before you upload.