KDP Cover and Spine Width: How to Calculate Exact Dimensions

Your book's cover is the first thing readers see. But KDP formatting is strict — Amazon will reject your cover if the spine width doesn't match your page count exactly. Here's how to get your KDP format right for book formatting.

The KDP Format Spine Width Formula

According to Amazon KDP's official formatting guidelines:

• White paper: Spine width = page count × 0.002252 inches
• Cream paper: Spine width = page count × 0.0025 inches

For example, a 200-page book on white paper: 200 × 0.002252 = 0.4504 inches spine width.

Full Cover Dimensions

The full cover wrap includes the back cover, spine, and front cover in one image:

• Width: Back cover + spine + front cover + bleed
• Height: Trim height + bleed (0.125" top and bottom)

For a 6×9 book (200 pages, white paper):

• Back cover: 6.0 inches
• Spine: 0.4504 inches
• Front cover: 6.0 inches
• Bleed: 0.125 inches on each side
• Total width: 0.125 + 6.0 + 0.4504 + 6.0 + 0.125 = 12.7004 inches
• Total height: 0.125 + 9.0 + 0.125 = 9.25 inches

Minimum Spine Text Requirements

• Under 0.5 inches (under ~100 pages): No text allowed on the spine
• 0.5 inches or more: Spine text is optional
• Keep spine text centered with margins to avoid wrapping

Common Cover Mistakes

• Wrong spine width: Even 0.01 inches off causes rejection
• Wrong resolution: Must be 300 DPI minimum
• Text too close to edges: Keep text 0.25 inches from trim lines
• Barcode area: Leave space on the back cover for KDP's barcode

Cover File Requirements

• Format: PDF (preferred) or JPEG/TIFF
• Resolution: 300 DPI minimum
• Color space: CMYK for print
• Max file size: 650 MB

Automatic KDP Format Calculations

SimpleFormat Pro calculates your exact KDP formatting for spine width and full cover dimensions based on your page count and paper type. No manual book formatting math required.