Here are some of the best quality and affordable print-on-demand (POD) services for small color books (e.g., picture books, children's books, coloring books, or similar formats like 6x9, 8x8, 8.5x8.5, or square sizes) that support 300 dpi quality requirements. All these platforms accept high-resolution files at 300 dpi (the industry standard for sharp print results), and they specialize in full-color interiors.

These options balance affordability (lower per-book printing costs for small runs or single copies), print quality for vibrant colors, and ease of use for self-publishers. Prices vary based on exact specs (page count, size, paper type, binding), but I'll note typical ranges and strengths as of recent comparisons.

1. Amazon KDP (Kindle Direct Publishing)

One of the most affordable and accessible POD options, especially if you're selling primarily through Amazon.

• Supports small sizes (e.g., 6x9, 8.5x8.5, and many custom trim sizes).
• Premium color option for vivid, high-quality full-color interiors (standard color is cheaper but duller).
• Requires 300 dpi images for best results.
• Very low printing costs (e.g., often $3–$6+ for a 32–64 page small color book, depending on pages).
• Great for beginners with no upfront fees, fast production, and global reach.
• Drawback: Quality is solid but not always the absolute best for highly detailed illustrations compared to premium specialists.

It's ideal for testing the market or keeping costs minimal.

2. IngramSpark

Offers excellent value for color books with wide distribution (bookstores, libraries, beyond just Amazon).

• Supports many small/custom sizes and premium color options (standard color is more affordable, premium for better vibrancy).
• 300 dpi required for sharp results.
• Often cheaper printing costs than KDP for premium color (e.g., $2.50–$5+ for small color books in moderate page counts).
• High quality with good color accuracy.
• Setup fees apply (but can be waived with promotions), and it's great for professional distribution.

A strong choice if you want broader reach without sacrificing too much on price.

3. Mixam

Frequently praised for high-quality color reproduction, affordability, and flexibility in small formats — especially good for illustrated or children's-style books.

• Wide range of small sizes (square, landscape, custom).
• Excellent vibrant color printing on various paper stocks.
• Accepts 300 dpi files; known for sharp, professional results.
• Competitive pricing for POD (often more affordable than many competitors for quality color work, with print-on-demand via their PrintLink tool).
• Supports single copies to bulk, with easy integration for direct sales (e.g., Shopify).
• Users highlight great color accuracy (98%+ in reviews) and sturdy builds.

This is a top pick for quality-conscious creators who want vivid results without high costs.

4. Lulu

Very customizable for small color books, including unique sizes like square hardcovers or children's formats.

• Tons of trim sizes, paper types, and premium color options.
• Requires 300 dpi for images.
• Affordable for small runs, with transparent pricing (often competitive for premium color).
• Good quality for illustrated work.
• Easy to use, with options for direct sales or distribution.

Solid all-around option if you need lots of format flexibility.

5. Blurb

Best for premium visual quality (great for photo-heavy or highly illustrated small color books).

• Specializes in custom sizes and high-end color printing.
• 300 dpi standard.
• Higher costs per book (less "affordable" than the above), but excellent sharpness and paper options.
• Ideal if quality is priority over rock-bottom price.

Consider this if your book is very image-dependent (e.g., picture books).

Quick Tips for All Services:

• Upload files in CMYK at 300 dpi with proper bleed/margins for best results.
• Order author proof copies first to check color accuracy.
• For very small runs (1–50 copies), KDP or Mixam often win on price; for wider distribution, IngramSpark shines.

If your book has a specific size/page count (e.g., 32-page 8x8 children's book), feel free to share more details for tailored recommendations! Many users in 2025–2026 reviews highlight Mixam and IngramSpark for the best quality-to-price ratio in color POD.