How Thick Should Coloring Book Paper Be? A Practical Guide
Most people don't think about paper weight until they've already printed their coloring book, and the marker bleeds straight through to the next page. And if you're printing single sided, the issue is even worse: thin paper is so light that color transfers not just to the reverse side but onto the next page in the stack too.
Paper thickness is one of the few decisions you make once and live with forever. Choose too light, and the book becomes frustrating to color in. Choose too heavy, and you spend a little more, but honestly that's a tradeoff I'll almost always take.
If you plan to use a print-on-demand service (POD for short, meaning a printer that prints and ships each book individually as orders come in, rather than running a large batch upfront), you should know upfront: getting genuinely thick, high-quality coloring book paper is the single biggest challenge of using POD. The big platforms simply don't stock the heavy stock that coloring books really want.
This guide covers exactly how paper thickness is measured, what you actually need based on what you're coloring with, and the small details that make the difference between paper that holds up and paper that fails.
How Paper Thickness Is Measured: GSM
Paper thickness is most commonly measured in GSM, which stands for grams per square meter. It tells you how much one square meter of that specific paper would weigh. The higher the number, the thicker and heavier the paper. It's the international standard and the cleanest way to compare two papers on a like-for-like basis.
For reference: standard office printer paper is around 80 GSM. A typical magazine page is 60 to 80 GSM. The cardstock used for greeting cards is usually 250 to 350 GSM.
For coloring books, you're looking somewhere in the middle. The exact number depends on what people will be coloring with.
GSM vs Paper Weight Class (lb / #): Why It's Confusing
If you've shopped for paper in the US, you've probably seen weights written as 60#, 80#, or 100# (the # symbol means "pound"). This is the paper weight class system, and it's where things get genuinely confusing.
Unlike GSM, the lb / # number is not a direct measure of how heavy a single sheet is. It refers to the total weight of a 500-sheet ream of that paper at its original, uncut size. The catch: the original uncut size is different for different paper categories. A ream of "text" paper, "cover" paper, and "bond" paper are all cut from different parent sheet sizes, so 80# text and 80# cover end up being completely different thicknesses.
Translated to GSM, here's roughly what to expect for text/book paper (the category most coloring books use):
- 60# text ≈ 90 GSM
- 70# text ≈ 105 GSM
- 80# text ≈ 120 GSM
- 100# text ≈ 150 GSM
But the same number on a cover stock or cardstock means something completely different (80# cover is roughly 215 GSM, not 120). This is why two papers labeled "80#" can feel completely unalike, and why printers who quote in lb / # without specifying the paper category leave you guessing.
Whenever a print-on-demand service publishes its paper specs in lb / # without listing the GSM equivalent, the safest move is to ask, or order a proof copy and feel the paper yourself.
The Quick Answer
Minimum: 120 GSM. Below this, even colored pencils can dent the page and show through to the back, and on single sided prints the color can transfer onto the next sheet in the stack.
Recommended: 160 GSM. This is the sweet spot for most coloring books, heavy enough to handle pencils, gel pens, and light marker use without significant bleed-through.
Premium (for marker users): 200+ GSM. If you know the book will be colored with alcohol-based markers, you need genuinely thick paper to prevent ghosting and bleed.
Personally, I'll almost always recommend printing at the higher weight. It just feels more professional and thicker in the hand, and the small extra cost is worth it for a book that's meant to be kept.
How Coloring Medium Affects the Paper You Need
The right thickness depends almost entirely on what people will be coloring with. Here's how each medium behaves on paper.
Colored pencils are the most forgiving. They sit on the surface of the paper and don't soak in. 120 GSM is enough; 160 GSM feels noticeably more premium and reduces any chance of indentation showing on the back.
Gel pens and ballpoint pens deposit ink that dries on the surface. They handle well on 120 to 160 GSM paper. The main risk is smudging during use, not bleed-through.
Water-based markers (Crayola, kids' markers) carry water-based ink that's relatively gentle. 160 GSM handles them well in most cases. Lower weights will show some shadowing on the reverse side.
Alcohol-based markers (Copic, Ohuhu, Spectrum Noir) are a different category. The solvent soaks deep into paper fibers and bleeds through almost anything below 200 GSM. For marker artists, you either need very heavy paper (200+ GSM) or single-sided printing so bleed-through doesn't affect anything.
Watercolor or wet media requires specialized watercolor paper (300+ GSM, often textured). Standard coloring book paper isn't designed for wet media at all: pages will warp and tear.
Why Bleed-Through Matters More Than You Think
Bleed-through isn't just an aesthetic problem. When ink soaks through to the next page, it ruins the artwork on the reverse side. In a coloring book, that means losing a page you haven't even colored yet.
And if you print single sided, like I do, thin paper has another failure mode: the color can transfer through the blank back of the page and onto the next printed page underneath. Heavier paper protects against both problems at once.
There's also a related issue called ghosting, where the color on one side is faintly visible on the other, even without true bleed-through. Lighter paper shows ghosting more. 160 GSM noticeably reduces it; 200 GSM virtually eliminates it for most mediums.
Single-Sided vs Double-Sided Printing
One way to sidestep paper weight concerns entirely is to print single-sided: artwork on one side of each sheet, blank on the other. This is what I do.
This is the standard for premium and adult coloring books, especially those designed for marker use. It doubles your page count and the cost of printing, but it eliminates bleed-through to the reverse of the same sheet.
Important caveat: single-sided printing does not save you from thin paper. If the paper is too thin, color from one page can still transfer onto the next sheet through the blank back. So even when printing single sided, I still recommend 160 GSM or higher.
Paper Color: White vs Cream
Most print-on-demand platforms offer two paper colors:
White paper shows colors most accurately. Reds look red, blues look blue, and whites stay crisp. This is the standard choice for vibrant, modern coloring books. Personally, I always go with white for exactly this reason: color accuracy. What you put down is what you see.
Cream paper has a warm, slightly yellow tone. It's easier on the eyes for long coloring sessions and gives colors a softer, vintage feel. Cream is often preferred for adult coloring books and gift editions, but every color you lay down is filtered through that warm tone.
Paper color also affects spine width slightly: cream is marginally thicker per page than white, so the same page count produces a slightly wider spine on cream stock.
What Print-on-Demand Platforms Actually Offer
If you're using a POD service like Amazon KDP, Lulu, or IngramSpark, your paper choices are limited to what they stock. Here's what to expect from the big three, and the honest truth: none of them offer the paper thickness I personally prefer for coloring books. This is the single biggest limitation of going the POD route.
Amazon KDP tops out at around 105 GSM for standard interior paper, in white or cream. That's lighter than ideal for coloring books, which is one of the tradeoffs of using KDP for this purpose. Many KDP coloring books print single-sided to compensate.
Lulu doesn't standardize its paper by a single GSM value across all products. The actual paper weight (GSM equivalent) can vary depending on the print provider, book format, and production location. Because of this, Lulu does not publish fixed GSM specifications. Instead, their paper stocks are defined by weight class (for example, 60#, 80#, 100#). At this time, the highest uncoated paper weight class available on Lulu is 60# uncoated (white or cream). The next step up in physical thickness is 80# White Coated, which is thicker than 60# uncoated, but it's a coated stock and not available in an uncoated version, which makes it less ideal for coloring. For these reasons, Lulu isn't my favorite for self-publishing coloring books. The most reliable way to evaluate the feel is to order a proof copy and physically compare the stock before committing.
IngramSpark offers up to 70# paper, which maps to roughly 105 GSM. Still not as heavy as I'd like, but better than the alternatives at the upper end. As with Lulu, ordering a proof copy is the safest way to confirm the feel before committing.
The honest summary: if you want truly heavy 160+ GSM coloring book paper, none of the big three POD platforms will give it to you off the shelf. You either accept the lighter stock and print single-sided to compensate, or look at specialty printers.
Common Paper Weight Mistakes
Choosing the lightest option to save money. The savings are small per book; the impact on the user experience is large. If your book is meant to be used and kept, the paper needs to feel substantial.
Assuming all paper is the same. 90 GSM and 160 GSM look similar on a spec sheet but feel completely different in hand. If possible, order a proof copy before committing to a print run.
Comparing lb / # numbers across paper types. 80# text and 80# cover are completely different thicknesses. Always look at the GSM equivalent if you want a fair comparison.
Ignoring the medium your audience will use. A coloring book aimed at adults who use markers needs heavier paper than one aimed at kids using crayons. Match the paper to the realistic use case.
Forgetting that paper weight affects spine width. Heavier paper means a thicker book and a wider spine. This matters when designing your cover template.
Quick Reference: Thickness by Use Case
Kids' coloring book, crayons and pencils: 120 GSM minimum, 160 GSM ideal. Double-sided printing is fine.
Adult coloring book, pencils and gel pens: 160 GSM. Double-sided printing works well at this weight.
Adult coloring book, mixed media including markers: 200+ GSM, or 160 GSM with single-sided printing.
Premium gift or keepsake book: 200 GSM, white paper for color accuracy. Single-sided printing for a high-end feel.
Personalized coloring book made from photos: 160 GSM is the practical sweet spot. Heavy enough to feel substantial, light enough to stay affordable. Go higher if your budget allows; in my experience, you almost never regret thicker paper.
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Frequently Asked Questions About Coloring Book Paper Thickness
How thick should coloring book paper be?
120 GSM is the practical minimum. Below this, even colored pencils can leave indentations visible on the back of the page, and any pen or marker will show through. 160 GSM is the recommended weight for most coloring books, and going higher is almost always worth it for the more professional, thicker feel in hand.
What does GSM mean?
GSM stands for grams per square meter. It tells you how much a single square meter of that paper weighs, and it's the international standard for measuring paper thickness. The higher the GSM, the thicker and heavier the paper. Standard office printer paper is around 80 GSM; coloring book paper should be 120 GSM at minimum, 160 GSM ideally.
What does POD mean?
POD stands for print-on-demand. It's a printing model where each book is printed and shipped individually as orders come in, rather than printing a large batch upfront. Services like Amazon KDP, Lulu, and IngramSpark are POD platforms. The model is convenient and low-risk, but the paper options are limited to what each platform stocks, which is the biggest drawback for coloring books specifically.
Why are GSM and lb / # so confusing to compare?
GSM is a direct measurement of how much a square meter of the paper weighs, so it's consistent across any paper type. The lb / # system instead measures the weight of a 500-sheet ream at the paper's original uncut size, and that uncut size differs by paper category (text, cover, bond). So 80# text and 80# cover are completely different thicknesses. Whenever a printer publishes only lb / #, ask for the GSM equivalent or order a proof copy.
What thickness of paper is best for alcohol-based markers like Copic?
200 GSM minimum if you're printing double-sided. Alcohol markers soak deep into paper fibers and will bleed through almost any standard book paper. Many marker-friendly coloring books print single-sided specifically to avoid this problem, which lets you use lighter paper without the bleed-through issue, though even single sided you still want at least 160 GSM so color doesn't transfer onto the next sheet in the stack.
Will colored pencils bleed through 120 GSM paper?
Colored pencils don't bleed in the traditional sense; they don't use liquid ink. But on lighter paper, heavy pressure can leave indentations or color transfer visible on the reverse side. 120 GSM is generally fine for pencils; 160 GSM eliminates any risk of indentation and feels more premium.
Why does paper thickness matter for coloring books specifically?
Coloring books get used differently than novels. Pages are pressed against, colored over, sometimes torn out and framed. Heavier paper holds up to that handling. It also prevents ink from one page ruining the artwork on the next, which is unique to coloring books because you're creating new art on every page.
Does single-sided printing solve the bleed-through problem completely?
It eliminates bleed-through onto the reverse of the same sheet, but not the risk of color transferring onto the next page in the stack if the paper is too thin. Even on single sided prints, very thin paper can let pigment show on the page below. 160 GSM or higher is the safest choice regardless of single or double sided.
What's the difference between white and cream paper for coloring books?
White paper shows colors most accurately and gives a crisp, modern feel. I personally always recommend white for color accuracy: what you lay down is what you see. Cream paper has a warm, slightly yellow tone that's easier on the eyes and gives a softer, vintage feel, but every color you apply is filtered through that warmth. Cream is also marginally thicker per page than white at the same weight rating.
Should I print my coloring book single-sided or double-sided?
Single-sided printing is standard for premium and marker-friendly coloring books because it eliminates bleed-through onto the reverse of the same sheet. It's what I do. Double-sided is more cost-effective and works well for pencils, gel pens, and light marker use on 160+ GSM paper. The choice depends on your budget and what mediums your audience will use.
Does Amazon KDP offer paper heavy enough for coloring books?
KDP tops out at around 105 GSM for standard interior paper, which is lighter than ideal for coloring books. Many coloring book authors on KDP print single-sided to compensate.
What thickness of paper does Lulu offer?
Lulu doesn't standardize by a single GSM value. They publish paper stocks by weight class (60#, 80#, 100#) instead. Their highest uncoated weight class is 60# uncoated. The next step up in thickness is 80# White Coated, but it's a coated stock, which isn't ideal for coloring. For that reason, Lulu isn't my preferred option for self-publishing coloring books. Order a proof copy to physically evaluate the stock before committing.
What thickness of paper does IngramSpark offer?
IngramSpark offers up to 70# paper, which maps to roughly 105 GSM. Heavier than Lulu's uncoated options but still below the 160 GSM I'd recommend. Better than the alternatives at the top end of the big three platforms, but still not in the truly premium range.
Is paper quality the biggest challenge with print-on-demand?
For coloring books, yes. The big POD platforms are excellent at making printing accessible and low-risk, but none of them stock the truly thick, heavy paper that coloring books really benefit from. If premium paper is essential to your project, you'll either need to compromise on stock and print single-sided to compensate, or move to a specialty printer outside the standard POD model.
Does paper thickness affect the cost of printing?
Yes, but less than you might expect. Moving from 120 GSM to 160 GSM typically adds a small amount per copy, often pennies on a per-book basis with most print-on-demand services. The difference in feel and durability is significant; the cost difference rarely is. This is why I almost always recommend printing at the higher weight.
How does GSM compare to "lb" weight in the US?
The US uses pounds (lb) instead of GSM, but the conversion isn't always straightforward because it depends on paper type. As a rough guide for text/book paper: 60lb is around 90 GSM, 70lb is around 105 GSM, 80lb is around 120 GSM, and 100lb is around 150 GSM. For coloring books, look for 80lb or higher; 100lb is ideal.
Next in the seriesWhat Is Print on Demand? A Coloring Book Creator's Guide