Book Printing Paper Types Glossary: Complete Reference for KDP Authors

Basis Weight (BW) - The weight of 500 sheets of paper in its basic size, measured in pounds. For book printing, text papers typically range from 50-70 pounds, while cover stocks range from 80-120 pounds. KDP uses 60# text weight for paperback interiors.

Why it matters: Heavier paper feels more premium but increases printing costs and shipping weight.

GSM (Grams per Square Meter) - International measurement of paper weight based on grams per square meter. KDP paperbacks use 60 GSM cream paper, while hardcovers use 70 GSM white paper. Most commercial books range from 55-90 GSM.

Why it matters: GSM directly affects your book's thickness, weight, and perceived quality.

Caliper - The thickness of a single sheet of paper measured in thousandths of an inch (mils) or millimeters. Standard book paper ranges from 3.5-5.5 mils. Thicker paper creates bulkier books but feels more substantial.

Why it matters: Caliper affects spine width calculations and overall book handling experience.

PPI (Pages Per Inch) - How many pages fit in one inch of book thickness. Standard 60 GSM paper yields approximately 400-450 PPI. Lower PPI means thicker books, which can affect shipping costs and shelf appeal.

Why it matters: PPI helps calculate final book dimensions and printing costs for bulk orders.

Cream Paper - Off-white paper with a warm, yellowish tint that reduces eye strain and provides a traditional book feel. KDP's standard cream paper has an opacity rating of 94%. Popular for fiction, memoirs, and text-heavy non-fiction.

Why it matters: Cream paper hides slight printing imperfections better than white paper and creates a premium reading experience.

White Paper - Bright white paper that provides maximum contrast for text and images. KDP offers white paper for hardcovers and as an upgrade option for paperbacks. Opacity typically ranges from 92-96%.

Why it matters: White paper is essential for color images, children's books, and technical manuals with diagrams.

Opacity - The paper's ability to prevent text or images from showing through from the opposite side, measured as a percentage. Professional book paper should have 94% or higher opacity to prevent show-through.

Why it matters: Low opacity creates distracting show-through that makes books appear cheap and difficult to read.

Brightness - The amount of light reflected by paper, measured on a scale of 1-100. Standard book papers range from 82-92 brightness. Higher brightness provides better contrast for black text.

Why it matters: Proper brightness ensures text readability without causing eye strain from excessive glare.

Uncoated Paper - Paper without surface coating, providing a natural texture that's easy to write on and absorbs ink well. Standard for most text-based books. KDP uses uncoated paper for all interior pages.

Why it matters: Uncoated paper costs less and works best for text-heavy books where readability matters more than image quality.

Coated Paper - Paper with a surface coating that creates a smooth finish and enhances image reproduction. Available in matte, satin, and gloss finishes. Increases printing costs by 15-25% but dramatically improves photo quality.

Why it matters: Essential for photography books, art books, and children's books with detailed illustrations.

Matte Finish - A coated paper with low gloss that reduces glare while maintaining good image quality. Popular for coffee table books and art publications where fingerprints and glare are concerns.

Why it matters: Matte finish provides the best balance between image quality and readability for mixed-content books.

Satin Finish - A coating that falls between matte and gloss, offering moderate sheen with good image reproduction. Less prone to fingerprints than gloss but more reflective than matte.

Why it matters: Satin finish works well for books with both text and images, providing versatility without extreme characteristics.

Gloss Finish - High-shine coating that maximizes color saturation and image sharpness. Most expensive option but provides magazine-quality reproduction for photos and graphics.

Why it matters: Gloss finish is necessary for high-end photography books and premium publications where image quality is paramount.

Grain Direction - The alignment of paper fibers, either with the grain (long-grain) or against it (short-grain). Books should be printed long-grain for better binding durability and page-turning characteristics.

Why it matters: Proper grain direction prevents pages from tearing easily and ensures the book lies flat when open.

Long-Grain - Paper where fibers run parallel to the longest dimension. Preferred for book printing because pages fold and tear more cleanly along the grain. KDP automatically uses long-grain orientation.

Why it matters: Long-grain paper creates more durable bindings and better page-turning experience for readers.

Short-Grain - Paper where fibers run parallel to the shortest dimension. Generally avoided for book printing due to poor folding characteristics and binding problems.

Why it matters: Short-grain paper can cause pages to crack along the spine and creates an inferior reading experience.

Acid-Free Paper - Paper manufactured without acids that cause yellowing and deterioration over time. All professional book papers should be acid-free to ensure longevity.

Why it matters: Acid-free designation means your books will maintain their appearance for 50+ years without yellowing or becoming brittle.

Virgin Fiber - Paper made from new wood pulp rather than recycled materials. Provides consistent quality and color but costs more than recycled alternatives.

Why it matters: Virgin fiber ensures uniform appearance and performance, critical for professional book publishing.

Offset Paper - Uncoated paper specifically designed for offset printing presses. Provides excellent ink absorption and consistent quality for text reproduction. Standard choice for most commercial book printing.

Why it matters: Offset paper delivers the best text clarity and cost-effectiveness for novels and text-based non-fiction.

Book Paper - Generic term for papers specifically manufactured for book printing, typically 50-70# weight with high opacity and good printability. Optimized for readability and durability.

Why it matters: Book paper is engineered specifically for your use case, providing better performance than general printing papers.

Text Paper - Lightweight paper (typically 50-70#) used for book interiors. Designed for high-volume printing with consistent ink absorption and minimal show-through.

Why it matters: Text paper provides the optimal balance of cost, weight, and readability for most book projects.

Cover Stock - Heavier paper (80-120#) used for book covers and dust jackets. Provides durability and premium feel while accepting high-quality image printing.

Why it matters: Cover stock protects your book's interior and creates the critical first impression that drives purchase decisions.

Newsprint - Lightweight, inexpensive paper made from recycled materials. Suitable only for temporary publications due to poor longevity and image quality.

Why it matters: Newsprint is too low-quality for professional book publishing but understanding it helps you avoid cheap alternatives.

GSM vs Basis Weight - GSM measures grams per square meter (international), while basis weight measures pounds per 500 sheets in standard size (US system). A 60 GSM paper equals approximately 40# basis weight for text papers.

Opacity vs Brightness - Opacity prevents show-through (higher is better), while brightness measures light reflection (moderate levels preferred). You need both: 94%+ opacity and 85-90 brightness for optimal readability.

Matte vs Uncoated - Matte is a coated paper with low gloss, while uncoated has no surface treatment. Matte costs more but provides better image quality than uncoated.

Grain Direction vs Paper Weight - Grain direction refers to fiber alignment (long-grain preferred), while paper weight measures thickness/density. Both affect book quality but serve different purposes.

Virgin vs Recycled Fiber - Virgin fiber comes from new wood pulp (consistent quality), while recycled uses post-consumer waste (environmental benefit). Virgin typically provides better color consistency for professional publishing.