Mistake #1: Wrong cover size (canvas doesn’t match KDP)
If your exported file is rejected or looks “off” in preview, confirm you designed on the full cover size (front + spine + back + bleed). Use the calculator to generate the exact size for your configuration, then re-check trim in KDP Trim Sizes: How to Choose the Right Book Size. If you’re using Canva, the blog post KDP Cover Wrong Size in Canva: Fixes That Work is a good deep dive.
Mistake #2: Pixelated or fuzzy text
This usually happens when text is rasterized at a low resolution or exported with the wrong settings. Review export tips in Fix Pixelated Fonts on KDP Covers, then apply the same readability principles from KDP Cover Design Principles: Hierarchy, Contrast, and Readability.
Mistake #3: Barcode collisions on the back cover
Leave a clean area on the lower-right back cover and avoid placing key illustrations or copy there. If you want a safer shortcut, start from KDP Cover Templates and keep your elements comfortably inside the safe area.
Mistake #4: Spine alignment issues
If your spine text is off-center, the spine width is often wrong or your layout isn’t designed with enough tolerance. Recalculate using Spine Width for KDP: The Practical Guide (+ Calculator Tips), then re-export.
Mistake #5: Skipping a repeatable workflow
Most errors happen at the finish line—right before upload. The fix is boring but effective: use a consistent checklist every time. Go to KDP Cover Workflow Checklist: From Brief → Export → Upload and run a final preflight pass before you upload.